add in river investigative module. revamp the services to use dedicated services for api and submission

lib/auth_provider.dart

@@ -1,12 +1,13 @@
 // lib/auth_provider.dart
 
-import 'package:flutter/foundation.dart'; // Import for compute function
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/scheduler.dart'; // Added import for post-frame callback
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:connectivity_plus/connectivity_plus.dart';
 import 'dart:convert';
 import 'package:bcrypt/bcrypt.dart'; // Import bcrypt
-import 'package:flutter_secure_storage/flutter_secure_storage.dart'; // NEW: Import secure storage
+import 'package:flutter_secure_storage/flutter_secure_storage.dart'; // Import secure storage
 
 import 'package:environment_monitoring_app/services/api_service.dart';
 import 'package:environment_monitoring_app/services/base_api_service.dart';
@@ -14,6 +15,9 @@ import 'package:environment_monitoring_app/services/server_config_service.dart';
 import 'package:environment_monitoring_app/services/retry_service.dart';
 import 'package:environment_monitoring_app/services/user_preferences_service.dart';
 
+// Removed _CacheDataContainer class
+// Removed _loadCacheDataFromIsolate function
+
 class AuthProvider with ChangeNotifier {
   late final ApiService _apiService;
   late final DatabaseHelper _dbHelper;
@@ -21,7 +25,7 @@ class AuthProvider with ChangeNotifier {
   late final RetryService _retryService;
   final UserPreferencesService _userPreferencesService = UserPreferencesService();
 
-  // NEW: Initialize secure storage
+  // Initialize secure storage
   final _secureStorage = const FlutterSecureStorage();
   static const _passwordStorageKey = 'user_password';
 
@@ -34,15 +38,15 @@ class AuthProvider with ChangeNotifier {
   Map<String, dynamic>? get profileData => _profileData;
 
   // --- App State ---
-  bool _isLoading = true;
+  bool _isLoading = true; // Keep true initially
   bool _isFirstLogin = true;
   DateTime? _lastSyncTimestamp;
+  bool _isBackgroundLoading = false; // Added flag for background loading
   bool get isLoading => _isLoading;
+  bool get isBackgroundLoading => _isBackgroundLoading;
   bool get isFirstLogin => _isFirstLogin;
   DateTime? get lastSyncTimestamp => _lastSyncTimestamp;
 
-  /// This flag indicates the session is confirmed expired and auto-relogin failed.
-  /// The app should operate in offline mode until the user manually logs in again.
   bool _isSessionExpired = false;
   bool get isSessionExpired => _isSessionExpired;
 
@@ -60,12 +64,9 @@ class AuthProvider with ChangeNotifier {
   List<Map<String, dynamic>>? _airManualStations;
   List<Map<String, dynamic>>? _states;
   List<Map<String, dynamic>>? _appSettings;
-  // --- START: MODIFIED PARAMETER LIMITS PROPERTIES ---
-  // The old generic list has been removed and replaced with three specific lists.
   List<Map<String, dynamic>>? _npeParameterLimits;
   List<Map<String, dynamic>>? _marineParameterLimits;
   List<Map<String, dynamic>>? _riverParameterLimits;
-  // --- END: MODIFIED PARAMETER LIMITS PROPERTIES ---
   List<Map<String, dynamic>>? _apiConfigs;
   List<Map<String, dynamic>>? _ftpConfigs;
   List<Map<String, dynamic>>? _documents;
@@ -85,11 +86,9 @@ class AuthProvider with ChangeNotifier {
   List<Map<String, dynamic>>? get airManualStations => _airManualStations;
   List<Map<String, dynamic>>? get states => _states;
   List<Map<String, dynamic>>? get appSettings => _appSettings;
-  // --- START: GETTERS FOR NEW PARAMETER LIMITS ---
   List<Map<String, dynamic>>? get npeParameterLimits => _npeParameterLimits;
   List<Map<String, dynamic>>? get marineParameterLimits => _marineParameterLimits;
   List<Map<String, dynamic>>? get riverParameterLimits => _riverParameterLimits;
-  // --- END: GETTERS FOR NEW PARAMETER LIMITS ---
   List<Map<String, dynamic>>? get apiConfigs => _apiConfigs;
   List<Map<String, dynamic>>? get ftpConfigs => _ftpConfigs;
   List<Map<String, dynamic>>? get documents => _documents;
@@ -113,7 +112,7 @@ class AuthProvider with ChangeNotifier {
         _serverConfigService = serverConfigService,
         _retryService = retryService {
     debugPrint('AuthProvider: Initializing...');
-    _loadSessionAndSyncData();
+    _initializeAndLoadData(); // Use the updated method name
   }
 
   Future<bool> isConnected() async {
@@ -121,22 +120,35 @@ class AuthProvider with ChangeNotifier {
     return !connectivityResult.contains(ConnectivityResult.none);
   }
 
-  Future<void> _loadSessionAndSyncData() async {
+  // Updated method using SchedulerBinding instead of compute
+  Future<void> _initializeAndLoadData() async {
     _isLoading = true;
-    notifyListeners();
+    notifyListeners(); // Notify UI about initial loading state
 
+    // 1. Perform quick SharedPreferences reads first.
     final prefs = await SharedPreferences.getInstance();
     _jwtToken = prefs.getString(tokenKey);
     _userEmail = prefs.getString(userEmailKey);
     _isFirstLogin = prefs.getBool(isFirstLoginKey) ?? true;
 
+    final profileJson = prefs.getString(profileDataKey);
+    if (profileJson != null) {
+      try {
+        _profileData = jsonDecode(profileJson);
+      } catch (e) {
+        debugPrint("Failed to decode profile from prefs: $e");
+        prefs.remove(profileDataKey);
+      }
+    }
+
+    // Load server config early
     final activeApiConfig = await _serverConfigService.getActiveApiConfig();
     if (activeApiConfig == null) {
       debugPrint("AuthProvider: No active API config found. Setting default bootstrap URL.");
       final initialConfig = {
         'api_config_id': 0,
         'config_name': 'Default Server',
-        'api_url': 'https://mms-apiv4.pstw.com.my/v1',
+        'api_url': 'https://mms-apiv4.pstw.com.my/v1', // Use actual default if needed
       };
       await _serverConfigService.setActiveApiConfig(initialConfig);
     }
@@ -151,18 +163,40 @@ class AuthProvider with ChangeNotifier {
       }
     }
 
-    await _loadDataFromCache();
+    // 2. Set isLoading to false *before* scheduling heavy work.
+    _isLoading = false;
+    notifyListeners(); // Let the UI build
 
+    // 3. Schedule heavy database load *after* the first frame.
+    SchedulerBinding.instance.addPostFrameCallback((_) async {
+      debugPrint("AuthProvider: First frame built. Starting background cache load...");
+      _isBackgroundLoading = true; // Indicate background activity
+      notifyListeners(); // Show a secondary loading indicator if needed
+
+      try {
+        // Call the original cache loading method here
+        await _loadDataFromCache();
+        debugPrint("AuthProvider: Background cache load complete.");
+
+        // After loading cache, check session status and potentially sync
         if (_jwtToken != null) {
           debugPrint('AuthProvider: Session loaded.');
           await _userPreferencesService.applyAndSaveDefaultPreferencesIfNeeded();
-      // Sync logic moved to checkAndTransitionToOnlineSession to handle transitions correctly
+          // Decide whether to call checkAndTransition or validateAndRefresh here
+          await checkAndTransitionToOnlineSession(); // Example: Check if transition needed
+          await validateAndRefreshSession();       // Example: Validate if already online
         } else {
           debugPrint('AuthProvider: No active session. App is in offline mode.');
         }
 
-    _isLoading = false;
-    notifyListeners();
+      } catch (e) {
+        debugPrint("AuthProvider: Error during background cache load: $e");
+        // Handle error appropriately
+      } finally {
+        _isBackgroundLoading = false; // Background load finished
+        notifyListeners(); // Update UI
+      }
+    });
   }
 
   /// Checks if the session is offline and attempts to transition to an online session by performing a silent re-login.
@@ -178,20 +212,18 @@ class AuthProvider with ChangeNotifier {
     final bool inOfflineSession = _jwtToken != null && _jwtToken!.startsWith("offline-session-");
     if (!inOfflineSession) {
       // Already online or logged out, no transition needed.
-      // If online, trigger a normal sync to ensure data freshness on connection restoration.
+      // --- START: FIX FOR DOUBLE SYNC ---
+      // Removed the redundant syncAllData call from here.
       if(_jwtToken != null) {
-        debugPrint("AuthProvider: Session is already online. Triggering standard sync.");
-        // FIX: Add try-catch to prevent unhandled exceptions from crashing the app during background syncs.
-        try {
-          await syncAllData();
-        } catch (e) {
-          debugPrint("AuthProvider: Background sync failed silently on transition check: $e");
-        }
+        debugPrint("AuthProvider: Session is already online. Skipping transition sync.");
+        // Consider calling validateAndRefreshSession() here instead if needed,
+        // but avoid a full syncAllData().
       }
+      // --- END: FIX FOR DOUBLE SYNC ---
       return false;
     }
 
-    // FIX: Read password from secure storage instead of temporary variable.
+    // Read password from secure storage
     final String? password = await _secureStorage.read(key: _passwordStorageKey);
     if (password == null || _userEmail == null) {
       debugPrint("AuthProvider: In offline session, but no password in secure storage for auto-relogin. Manual login required.");
@@ -209,13 +241,12 @@ class AuthProvider with ChangeNotifier {
         final Map<String, dynamic> profile = result['data']['profile'];
 
         // Use existing login method to set up session and trigger sync.
-        await login(token, profile, password);
+        await login(token, profile, password); // This call includes syncAllData
 
         notifyListeners(); // Ensure UI updates after state change
         return true;
       } else {
-        // Silent login failed (e.g., password changed on another device).
-        // Keep user in offline mode for now. They will need to log out and log back in manually.
+        // Silent login failed
         debugPrint("AuthProvider: Silent re-login failed: ${result['message']}");
         return false;
       }
@@ -225,8 +256,6 @@ class AuthProvider with ChangeNotifier {
     }
   }
 
-  /// ⚡️ Orchestrates session validation and silent re-authentication.
-  /// This should be called whenever the app gains an internet connection.
   Future<void> validateAndRefreshSession() async {
     if (!(await isConnected())) {
       debugPrint('AuthProvider: No connection, skipping session validation.');
@@ -238,9 +267,8 @@ class AuthProvider with ChangeNotifier {
       return;
     }
 
-    // Don't attempt validation if the user is not logged in or is in a temporary offline session.
     if (_jwtToken == null || _jwtToken!.startsWith("offline-session-")) {
-      return;
+      return; // No online session to validate
     }
 
     try {
@@ -254,7 +282,6 @@ class AuthProvider with ChangeNotifier {
         debugPrint('AuthProvider: Silent re-login failed. Switching to session-expired offline mode.');
         _isSessionExpired = true;
         notifyListeners();
-        // You can optionally show a one-time notification here.
       } else {
         debugPrint('AuthProvider: Silent re-login successful. Session restored.');
       }
@@ -263,15 +290,12 @@ class AuthProvider with ChangeNotifier {
     }
   }
 
-  /// Attempts to silently re-login to get a new token.
-  /// This can be called when a 401 Unauthorized error is detected.
   Future<bool> attemptSilentRelogin() async {
     if (!(await isConnected())) {
       debugPrint("AuthProvider: No internet for silent relogin.");
       return false;
     }
 
-    // FIX: Read password from secure storage.
     final String? password = await _secureStorage.read(key: _passwordStorageKey);
     if (password == null || _userEmail == null) {
       debugPrint("AuthProvider: No cached credentials in secure storage for silent relogin.");
@@ -285,8 +309,10 @@ class AuthProvider with ChangeNotifier {
         debugPrint("AuthProvider: Silent re-login successful.");
         final String token = result['data']['token'];
         final Map<String, dynamic> profile = result['data']['profile'];
-        await login(token, profile, password);
-        _isSessionExpired = false; // Explicitly mark session as valid again.
+        // Critical: Call the main login function to update token, profile, hash, etc.
+        // BUT prevent it from triggering another full sync immediately if called during syncAllData
+        await _updateSessionInternals(token, profile, password); // Use helper to avoid sync loop
+        _isSessionExpired = false;
         notifyListeners();
         return true;
       } else {
@@ -299,13 +325,45 @@ class AuthProvider with ChangeNotifier {
     }
   }
 
+  // Helper to update session without triggering sync, used by attemptSilentRelogin
+  Future<void> _updateSessionInternals(String token, Map<String, dynamic> profile, String password) async {
+    _jwtToken = token;
+    _userEmail = profile['email'];
+
+    await _secureStorage.write(key: _passwordStorageKey, value: password);
+
+    final Map<String, dynamic> profileWithToken = Map.from(profile);
+    profileWithToken['token'] = token;
+    _profileData = profileWithToken;
+
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setString(tokenKey, token);
+    await prefs.setString(userEmailKey, _userEmail!);
+    await prefs.setString(profileDataKey, jsonEncode(_profileData));
+    await prefs.setString(lastOnlineLoginKey, DateTime.now().toIso8601String()); // Update last online time
+    await _dbHelper.saveProfile(_profileData!);
+
+    try {
+      debugPrint("AuthProvider: (Re-login) Hashing and caching password for offline login.");
+      final String hashedPassword = await compute(hashPassword, password);
+      await _dbHelper.upsertUserWithCredentials(
+        profile: profile,
+        passwordHash: hashedPassword,
+      );
+      debugPrint("AuthProvider: (Re-login) Credentials cached successfully.");
+    } catch (e) {
+      debugPrint("AuthProvider: (Re-login) Failed to cache password hash: $e");
+    }
+    // DO NOT call syncAllData here to prevent loops when called from syncAllData's catch block.
+  }
+
+
   Future<void> syncAllData({bool forceRefresh = false}) async {
     if (!(await isConnected())) {
       debugPrint("AuthProvider: Device is OFFLINE. Skipping sync.");
       return;
     }
 
-    // Proactively check if session is already marked as expired
     if (_isSessionExpired) {
       debugPrint("AuthProvider: Skipping sync, session is expired. Manual login required.");
       throw Exception('Session expired. Please log in again to sync.');
@@ -334,11 +392,10 @@ class AuthProvider with ChangeNotifier {
           debugPrint("AuthProvider: First successful sync complete. isFirstLogin flag set to false.");
         }
 
-        await _loadDataFromCache();
+        await _loadDataFromCache(); // Reload data after successful sync
         notifyListeners();
       } else {
         debugPrint("AuthProvider: Delta sync failed logically. Message: ${result['message']}");
-        // We throw an exception here so the UI can report a failure.
         throw Exception('Data sync failed. Please check the logs.');
       }
     } on SessionExpiredException {
@@ -355,12 +412,10 @@ class AuthProvider with ChangeNotifier {
       }
     } catch (e) {
       debugPrint("AuthProvider: A general error occurred during sync: $e");
-      // Re-throw the exception so the UI can display it.
       rethrow;
     }
   }
 
-  // --- START: NEW METHOD FOR REGISTRATION SCREEN ---
   Future<void> syncRegistrationData() async {
     if (!(await isConnected())) {
       debugPrint("AuthProvider: Device is OFFLINE. Skipping registration data sync.");
@@ -371,14 +426,13 @@ class AuthProvider with ChangeNotifier {
     final result = await _apiService.syncRegistrationData();
 
     if (result['success']) {
-      await _loadDataFromCache(); // Reload data from DB into the provider
-      notifyListeners();       // Notify the UI to rebuild
+      await _loadDataFromCache();
+      notifyListeners();
       debugPrint("AuthProvider: Registration data loaded and UI notified.");
     } else {
       debugPrint("AuthProvider: Registration data sync failed.");
     }
   }
-  // --- END: NEW METHOD FOR REGISTRATION SCREEN ---
 
   Future<void> refreshProfile() async {
     if (!(await isConnected())) {
@@ -390,10 +444,17 @@ class AuthProvider with ChangeNotifier {
       return;
     }
 
+    try {
       final result = await _apiService.refreshProfile();
       if (result['success']) {
         await setProfileData(result['data']);
       }
+    } on SessionExpiredException {
+      debugPrint("AuthProvider: Session expired during profile refresh. Attempting silent re-login...");
+      await attemptSilentRelogin(); // Attempt re-login but don't retry refresh automatically here
+    } catch (e) {
+      debugPrint("AuthProvider: Error during profile refresh: $e");
+    }
   }
 
   Future<void> proactiveTokenRefresh() async {
@@ -407,7 +468,7 @@ class AuthProvider with ChangeNotifier {
 
     if (lastOnlineLoginString == null) {
       debugPrint('AuthProvider: No last online login timestamp found, skipping proactive refresh.');
-      return; // Never logged in online, nothing to refresh.
+      return;
     }
 
     try {
@@ -423,14 +484,15 @@ class AuthProvider with ChangeNotifier {
     }
   }
 
+  // This method performs the actual DB reads
   Future<void> _loadDataFromCache() async {
     final prefs = await SharedPreferences.getInstance();
     final profileJson = prefs.getString(profileDataKey);
-    if (profileJson != null) {
-      _profileData = jsonDecode(profileJson);
-    } else {
-      _profileData = await _dbHelper.loadProfile();
+    if (profileJson != null && _profileData == null) {
+      try { _profileData = jsonDecode(profileJson); } catch(e) { /*...*/ }
     }
+    _profileData ??= await _dbHelper.loadProfile();
+
     _allUsers = await _dbHelper.loadUsers();
     _tarballStations = await _dbHelper.loadTarballStations();
     _manualStations = await _dbHelper.loadManualStations();
@@ -444,65 +506,40 @@ class AuthProvider with ChangeNotifier {
     _airManualStations = await _dbHelper.loadAirManualStations();
     _states = await _dbHelper.loadStates();
     _appSettings = await _dbHelper.loadAppSettings();
-
-    // --- START: LOAD DATA FROM NEW PARAMETER LIMIT TABLES ---
     _npeParameterLimits = await _dbHelper.loadNpeParameterLimits();
     _marineParameterLimits = await _dbHelper.loadMarineParameterLimits();
     _riverParameterLimits = await _dbHelper.loadRiverParameterLimits();
-    // --- END: LOAD DATA FROM NEW PARAMETER LIMIT TABLES ---
-
     _documents = await _dbHelper.loadDocuments();
     _apiConfigs = await _dbHelper.loadApiConfigs();
     _ftpConfigs = await _dbHelper.loadFtpConfigs();
-    _pendingRetries = await _retryService.getPendingTasks();
-    debugPrint("AuthProvider: All master data loaded from local DB cache.");
+    _pendingRetries = await _retryService.getPendingTasks(); // Use service here is okay
+    debugPrint("AuthProvider: All master data loaded from local DB cache (background/sync).");
   }
 
+
   Future<void> refreshPendingTasks() async {
     _pendingRetries = await _retryService.getPendingTasks();
     notifyListeners();
   }
 
   Future<void> login(String token, Map<String, dynamic> profile, String password) async {
-    _jwtToken = token;
-    _userEmail = profile['email'];
-
-    // FIX: Save password to secure storage instead of in-memory variable.
-    await _secureStorage.write(key: _passwordStorageKey, value: password);
-
-    final Map<String, dynamic> profileWithToken = Map.from(profile);
-    profileWithToken['token'] = token;
-    _profileData = profileWithToken;
-
-    final prefs = await SharedPreferences.getInstance();
-    await prefs.setString(tokenKey, token);
-    await prefs.setString(userEmailKey, _userEmail!);
-    await prefs.setString(profileDataKey, jsonEncode(_profileData));
-    await prefs.setString(lastOnlineLoginKey, DateTime.now().toIso8601String());
-    await _dbHelper.saveProfile(_profileData!);
-
-    try {
-      debugPrint("AuthProvider: Hashing and caching password for offline login.");
-      final String hashedPassword = await compute(hashPassword, password);
-      await _dbHelper.upsertUserWithCredentials(
-        profile: profile,
-        passwordHash: hashedPassword,
-      );
-      debugPrint("AuthProvider: Credentials cached successfully.");
-    } catch (e) {
-      debugPrint("AuthProvider: Failed to cache password hash: $e");
-    }
+    // Call the internal helper first
+    await _updateSessionInternals(token, profile, password);
 
+    // Now proceed with post-login actions that *don't* belong in the helper
     debugPrint('AuthProvider: Login successful. Session and profile persisted.');
     await _userPreferencesService.applyAndSaveDefaultPreferencesIfNeeded();
+    // The main sync triggered by a direct user login
     await syncAllData(forceRefresh: true);
+    // Notify listeners *after* sync is attempted (or throws)
+    notifyListeners();
   }
 
+
   Future<bool> loginOffline(String email, String password) async {
     debugPrint("AuthProvider: Attempting offline login for user $email.");
 
     try {
-      // 1. Retrieve stored hash from the local database based on email.
       final String? storedHash = await _dbHelper.getUserPasswordHashByEmail(email);
 
       if (storedHash == null || storedHash.isEmpty) {
@@ -510,24 +547,20 @@ class AuthProvider with ChangeNotifier {
         return false;
       }
 
-      // 2. Verify the provided password against the stored hash.
       debugPrint("AuthProvider: Verifying password against stored hash...");
       final bool passwordMatches = await compute(verifyPassword, CheckPasswordParams(password, storedHash));
 
       if (passwordMatches) {
         debugPrint("AuthProvider: Offline password verification successful.");
-        // 3. Load profile data from local storage.
         final Map<String, dynamic>? cachedProfile = await _dbHelper.loadProfileByEmail(email);
         if (cachedProfile == null) {
           debugPrint("AuthProvider DEBUG: Offline login failed because profile data was missing, even though password matched.");
           return false;
         }
 
-        // 4. Initialize session state from cached profile data.
         _jwtToken = "offline-session-${DateTime.now().millisecondsSinceEpoch}";
         _userEmail = email;
 
-        // FIX: Save password to secure storage for future auto-relogin.
         await _secureStorage.write(key: _passwordStorageKey, value: password);
 
         final Map<String, dynamic> profileWithToken = Map.from(cachedProfile);
@@ -539,6 +572,8 @@ class AuthProvider with ChangeNotifier {
         await prefs.setString(userEmailKey, _userEmail!);
         await prefs.setString(profileDataKey, jsonEncode(_profileData));
 
+        // Load cache data immediately after offline login succeeds
+        // This doesn't need the post-frame callback as it's triggered by user action
         await _loadDataFromCache();
         notifyListeners();
         return true;
@@ -561,7 +596,7 @@ class AuthProvider with ChangeNotifier {
 
     final prefs = await SharedPreferences.getInstance();
     await prefs.setString(profileDataKey, jsonEncode(_profileData));
-    await _dbHelper.saveProfile(_profileData!); // Also save to local DB
+    await _dbHelper.saveProfile(_profileData!);
     notifyListeners();
   }
 
@@ -579,11 +614,11 @@ class AuthProvider with ChangeNotifier {
     _profileData = null;
     _lastSyncTimestamp = null;
     _isFirstLogin = true;
-    _isSessionExpired = false; // Reset session expired flag on logout
+    _isSessionExpired = false;
 
-    // FIX: Clear password from secure storage on logout.
     await _secureStorage.delete(key: _passwordStorageKey);
 
+    // Clear cached data
     _allUsers = null;
     _tarballStations = null;
     _manualStations = null;
@@ -597,13 +632,9 @@ class AuthProvider with ChangeNotifier {
     _airManualStations = null;
     _states = null;
     _appSettings = null;
-
-    // --- START: Clear new parameter limit lists ---
     _npeParameterLimits = null;
     _marineParameterLimits = null;
     _riverParameterLimits = null;
-    // --- END: Clear new parameter limit lists ---
-
     _documents = null;
     _apiConfigs = null;
     _ftpConfigs = null;
@@ -615,7 +646,7 @@ class AuthProvider with ChangeNotifier {
     await prefs.remove(profileDataKey);
     await prefs.remove(lastSyncTimestampKey);
     await prefs.remove(lastOnlineLoginKey);
-    await prefs.remove('default_preferences_saved');
+    await prefs.remove('default_preferences_saved'); // Also clear user prefs flag
     await prefs.setBool(isFirstLoginKey, true);
 
     debugPrint('AuthProvider: All session and cached data cleared.');
@@ -623,10 +654,13 @@ class AuthProvider with ChangeNotifier {
   }
 
   Future<Map<String, dynamic>> resetPassword(String email) {
+    // Assuming _apiService has a method for this, otherwise implement it.
+    // This looks correct based on your previous code structure.
     return _apiService.post('auth/forgot-password', {'email': email});
   }
 }
 
+// These remain unchanged as they are used by compute for password hashing/checking
 class CheckPasswordParams {
   final String password;
   final String hash;

lib/collapsible_sidebar.dart

@@ -1,3 +1,5 @@
+// collapsible_sidebar.dart
+
 import 'package:flutter/material.dart';
 
 // --- Data Structure for Sidebar Menu Items ---
@@ -87,6 +89,8 @@ class _CollapsibleSidebarState extends State<CollapsibleSidebar> {
               SidebarItem(icon: Icons.pin_drop, label: "In-Situ Sampling", route: '/river/manual/in-situ'),
               SidebarItem(icon: Icons.date_range, label: "Triennial Sampling", route: '/river/manual/triennial'),
               SidebarItem(icon: Icons.article, label: "Data Log", route: '/river/manual/data-log'),
+              // *** ADDED: From river_home_page.dart ***
+              SidebarItem(icon: Icons.image, label: "Image Request", route: '/river/manual/image-request'),
             ],
           ),
           SidebarItem(
@@ -96,6 +100,8 @@ class _CollapsibleSidebarState extends State<CollapsibleSidebar> {
           SidebarItem(
               icon: Icons.search, label: "Investigative", isParent: true, children: [
             SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/river/investigative/info'),
+            // *** ADDED: From river_home_page.dart ***
+            SidebarItem(icon: Icons.biotech, label: "Investigative Sampling", route: '/river/investigative/manual-sampling'),
           ]),
         ],
       ),
@@ -115,6 +121,10 @@ class _CollapsibleSidebarState extends State<CollapsibleSidebar> {
               SidebarItem(icon: Icons.pin_drop, label: "In-Situ Sampling", route: '/marine/manual/in-situ'),
               SidebarItem(icon: Icons.waves, label: "Tarball Sampling", route: '/marine/manual/tarball'),
               SidebarItem(icon: Icons.article, label: "Data Log", route: '/marine/manual/data-log'),
+              // *** ADDED: From marine_home_page.dart ***
+              SidebarItem(icon: Icons.image, label: "Image Request", route: '/marine/manual/image-request'),
+              // *** ADDED: From marine_home_page.dart ***
+              SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/marine/manual/report'),
             ],
           ),
           SidebarItem(
@@ -124,6 +134,8 @@ class _CollapsibleSidebarState extends State<CollapsibleSidebar> {
           SidebarItem(
               icon: Icons.search, label: "Investigative", isParent: true, children: [
             SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/marine/investigative/info'),
+            // *** ADDED: From marine_home_page.dart ***
+            SidebarItem(icon: Icons.science_outlined, label: "Investigative Sampling", route: '/marine/investigative/manual-sampling'),
           ]),
         ],
       ),

lib/main.dart

@@ -10,13 +10,16 @@ import 'package:environment_monitoring_app/services/api_service.dart';
 import 'package:environment_monitoring_app/services/local_storage_service.dart';
 import 'package:environment_monitoring_app/services/river_in_situ_sampling_service.dart';
 import 'package:environment_monitoring_app/services/river_manual_triennial_sampling_service.dart';
+// *** ADDED: Import River Investigative Sampling Service ***
+import 'package:environment_monitoring_app/services/river_investigative_sampling_service.dart';
 import 'package:environment_monitoring_app/services/air_sampling_service.dart';
 import 'package:environment_monitoring_app/services/telegram_service.dart';
 import 'package:environment_monitoring_app/services/server_config_service.dart';
 import 'package:environment_monitoring_app/services/retry_service.dart';
 import 'package:environment_monitoring_app/services/marine_in_situ_sampling_service.dart';
+import 'package:environment_monitoring_app/services/marine_investigative_sampling_service.dart';
 import 'package:environment_monitoring_app/services/marine_npe_report_service.dart';
-import 'package:environment_monitoring_app/services/marine_tarball_sampling_service.dart';
+import 'package:environment_monitoring_app/services/marine_tarball_sampling_service.dart'; // Ensure this import is present
 import 'package:environment_monitoring_app/services/marine_manual_pre_departure_service.dart';
 import 'package:environment_monitoring_app/services/marine_manual_sonde_calibration_service.dart';
 import 'package:environment_monitoring_app/services/marine_manual_equipment_maintenance_service.dart';
@@ -66,6 +69,8 @@ import 'package:environment_monitoring_app/screens/river/continuous/overview.dar
 import 'package:environment_monitoring_app/screens/river/continuous/entry.dart' as riverContinuousEntry;
 import 'package:environment_monitoring_app/screens/river/continuous/report.dart' as riverContinuousReport;
 import 'package:environment_monitoring_app/screens/river/investigative/river_investigative_info_centre_document.dart';
+// *** ADDED: Import River Investigative Manual Sampling Screen ***
+import 'package:environment_monitoring_app/screens/river/investigative/river_investigative_manual_sampling.dart' as riverInvestigativeManualSampling;
 import 'package:environment_monitoring_app/screens/river/investigative/overview.dart' as riverInvestigativeOverview;
 import 'package:environment_monitoring_app/screens/river/investigative/entry.dart' as riverInvestigativeEntry;
 import 'package:environment_monitoring_app/screens/river/investigative/report.dart' as riverInvestigativeReport;
@@ -76,16 +81,22 @@ import 'package:environment_monitoring_app/screens/marine/manual/marine_manual_p
 import 'package:environment_monitoring_app/screens/marine/manual/in_situ_sampling.dart' as marineManualInSituSampling;
 import 'package:environment_monitoring_app/screens/marine/manual/marine_manual_report.dart' as marineManualReport;
 import 'package:environment_monitoring_app/screens/marine/manual/reports/marine_manual_npe_report_hub.dart';
-import 'package:environment_monitoring_app/screens/marine/manual/reports/marine_manual_pre_departure_checklist_screen.dart' as marineManualPreDepartureChecklist;
-import 'package:environment_monitoring_app/screens/marine/manual/reports/marine_manual_sonde_calibration_screen.dart' as marineManualSondeCalibration;
-import 'package:environment_monitoring_app/screens/marine/manual/reports/marine_manual_equipment_maintenance_screen.dart' as marineManualEquipmentMaintenance;
-import 'package:environment_monitoring_app/screens/marine/manual/marine_manual_data_status_log.dart' as marineManualDataStatusLog;
+import 'package:environment_monitoring_app/screens/marine/manual/reports/marine_manual_pre_departure_checklist_screen.dart'
+as marineManualPreDepartureChecklist;
+import 'package:environment_monitoring_app/screens/marine/manual/reports/marine_manual_sonde_calibration_screen.dart'
+as marineManualSondeCalibration;
+import 'package:environment_monitoring_app/screens/marine/manual/reports/marine_manual_equipment_maintenance_screen.dart'
+as marineManualEquipmentMaintenance;
+import 'package:environment_monitoring_app/screens/marine/manual/marine_manual_data_status_log.dart'
+as marineManualDataStatusLog;
 import 'package:environment_monitoring_app/screens/marine/manual/marine_image_request.dart' as marineManualImageRequest;
 import 'package:environment_monitoring_app/screens/marine/continuous/marine_continuous_info_centre_document.dart';
 import 'package:environment_monitoring_app/screens/marine/continuous/overview.dart' as marineContinuousOverview;
 import 'package:environment_monitoring_app/screens/marine/continuous/entry.dart' as marineContinuousEntry;
 import 'package:environment_monitoring_app/screens/marine/continuous/report.dart' as marineContinuousReport;
 import 'package:environment_monitoring_app/screens/marine/investigative/marine_investigative_info_centre_document.dart';
+import 'package:environment_monitoring_app/screens/marine/investigative/marine_investigative_manual_sampling.dart'
+as marineInvestigativeManualSampling;
 import 'package:environment_monitoring_app/screens/marine/investigative/overview.dart' as marineInvestigativeOverview;
 import 'package:environment_monitoring_app/screens/marine/investigative/entry.dart' as marineInvestigativeEntry;
 import 'package:environment_monitoring_app/screens/marine/investigative/report.dart' as marineInvestigativeReport;
@@ -105,6 +116,12 @@ void main() async {
   final RetryService retryService = RetryService();
   final MarineInSituSamplingService marineInSituService = MarineInSituSamplingService(telegramService);
   final RiverInSituSamplingService riverInSituService = RiverInSituSamplingService(telegramService);
+  final MarineInvestigativeSamplingService marineInvestigativeService =
+  MarineInvestigativeSamplingService(telegramService);
+  // *** ADDED: Create instance of RiverInvestigativeSamplingService ***
+  final RiverInvestigativeSamplingService riverInvestigativeService =
+  RiverInvestigativeSamplingService(telegramService);
+  final MarineTarballSamplingService marineTarballService = MarineTarballSamplingService(telegramService);
 
   telegramService.setApiService(apiService);
 
@@ -117,9 +134,13 @@ void main() async {
   );
 
   // Initialize the retry service with all its dependencies.
+  // *** MODIFIED: Added riverInvestigativeService dependency (and marineTarballService from previous request) ***
   retryService.initialize(
     marineInSituService: marineInSituService,
     riverInSituService: riverInSituService,
+    marineInvestigativeService: marineInvestigativeService,
+    riverInvestigativeService: riverInvestigativeService, // <-- Added this line
+    marineTarballService: marineTarballService,
     authProvider: authProvider,
   );
 
@@ -135,21 +156,23 @@ void main() async {
         Provider(create: (_) => LocalStorageService()),
         Provider.value(value: retryService),
         Provider.value(value: marineInSituService),
+        Provider.value(value: marineInvestigativeService),
         Provider.value(value: riverInSituService),
+        // *** ADDED: Provider for River Investigative Service ***
+        Provider.value(value: riverInvestigativeService), // Use Provider.value
         Provider(create: (context) => RiverManualTriennialSamplingService(telegramService)),
         Provider(create: (context) => AirSamplingService(databaseHelper, telegramService)),
-        Provider(create: (context) => MarineTarballSamplingService(telegramService)),
+        Provider.value(value: marineTarballService), // Use Provider.value
         Provider(create: (context) => MarineNpeReportService(Provider.of<TelegramService>(context, listen: false))),
-        // --- UPDATED: Inject ApiService into the service constructors ---
-        Provider(create: (context) => MarineManualPreDepartureService(
-            Provider.of<ApiService>(context, listen: false)
-        )),
-        Provider(create: (context) => MarineManualSondeCalibrationService(
-            Provider.of<ApiService>(context, listen: false)
-        )),
-        Provider(create: (context) => MarineManualEquipmentMaintenanceService(
-            Provider.of<ApiService>(context, listen: false)
-        )),
+        Provider(
+            create: (context) =>
+                MarineManualPreDepartureService(Provider.of<ApiService>(context, listen: false))),
+        Provider(
+            create: (context) =>
+                MarineManualSondeCalibrationService(Provider.of<ApiService>(context, listen: false))),
+        Provider(
+            create: (context) =>
+                MarineManualEquipmentMaintenanceService(Provider.of<ApiService>(context, listen: false))),
       ],
       child: const RootApp(),
     ),
@@ -182,7 +205,6 @@ class RootApp extends StatefulWidget {
 }
 
 class _RootAppState extends State<RootApp> {
-
   @override
   void initState() {
     super.initState();
@@ -255,8 +277,8 @@ class _RootAppState extends State<RootApp> {
           theme: AppTheme.darkBlueTheme,
           debugShowCheckedModeBanner: false,
           home: homeWidget,
-
           onGenerateRoute: (settings) {
+            // Keep existing onGenerateRoute logic for Tarball
             if (settings.name == '/marine/manual/tarball/step2') {
               final args = settings.arguments as TarballSamplingData;
               return MaterialPageRoute(builder: (context) {
@@ -274,7 +296,8 @@ class _RootAppState extends State<RootApp> {
                 return const marineManualDataStatusLog.MarineManualDataStatusLog();
               });
             }
-            return null;
+            // Add other potential dynamic routes here if necessary
+            return null; // Let routes map handle named routes
           },
           routes: {
             // Auth Routes
@@ -314,7 +337,8 @@ class _RootAppState extends State<RootApp> {
             '/river/manual/info': (context) => const RiverManualInfoCentreDocument(),
             '/river/manual/in-situ': (context) => riverManualInSituSampling.RiverInSituSamplingScreen(),
             '/river/manual/report': (context) => riverManualReport.RiverManualReport(),
-            '/river/manual/triennial': (context) => riverManualTriennialSampling.RiverManualTriennialSamplingScreen(),
+            '/river/manual/triennial': (context) =>
+                riverManualTriennialSampling.RiverManualTriennialSamplingScreen(),
             '/river/manual/data-log': (context) => riverManualDataStatusLog.RiverManualDataStatusLog(),
             '/river/manual/image-request': (context) => riverManualImageRequest.RiverManualImageRequest(),
 
@@ -326,9 +350,15 @@ class _RootAppState extends State<RootApp> {
 
             // River Investigative
             '/river/investigative/info': (context) => const RiverInvestigativeInfoCentreDocument(),
-            '/river/investigative/overview': (context) => riverInvestigativeOverview.OverviewScreen(),
-            '/river/investigative/entry': (context) => riverInvestigativeEntry.EntryScreen(),
-            '/river/investigative/report': (context) => riverInvestigativeReport.ReportScreen(),
+            // *** ADDED: Route for River Investigative Manual Sampling ***
+            '/river/investigative/manual-sampling': (context) =>
+                riverInvestigativeManualSampling.RiverInvestigativeManualSamplingScreen(),
+            '/river/investigative/overview': (context) =>
+                riverInvestigativeOverview.OverviewScreen(), // Keep placeholder/future routes
+            '/river/investigative/entry': (context) =>
+                riverInvestigativeEntry.EntryScreen(), // Keep placeholder/future routes
+            '/river/investigative/report': (context) =>
+                riverInvestigativeReport.ReportScreen(), // Keep placeholder/future routes
 
             // Marine Manual
             '/marine/manual/info': (context) => marineManualInfoCentreDocument.MarineInfoCentreDocument(),
@@ -337,9 +367,12 @@ class _RootAppState extends State<RootApp> {
             '/marine/manual/tarball': (context) => const TarballSamplingStep1(),
             '/marine/manual/report': (context) => const marineManualReport.MarineManualReportHomePage(),
             '/marine/manual/report/npe': (context) => const MarineManualNPEReportHub(),
-            '/marine/manual/report/pre-departure': (context) => const marineManualPreDepartureChecklist.MarineManualPreDepartureChecklistScreen(),
-            '/marine/manual/report/calibration': (context) => const marineManualSondeCalibration.MarineManualSondeCalibrationScreen(),
-            '/marine/manual/report/maintenance': (context) => const marineManualEquipmentMaintenance.MarineManualEquipmentMaintenanceScreen(),
+            '/marine/manual/report/pre-departure': (context) =>
+            const marineManualPreDepartureChecklist.MarineManualPreDepartureChecklistScreen(),
+            '/marine/manual/report/calibration': (context) =>
+            const marineManualSondeCalibration.MarineManualSondeCalibrationScreen(),
+            '/marine/manual/report/maintenance': (context) =>
+            const marineManualEquipmentMaintenance.MarineManualEquipmentMaintenanceScreen(),
             '/marine/manual/image-request': (context) => const marineManualImageRequest.MarineImageRequestScreen(),
 
             // Marine Continuous
@@ -350,6 +383,8 @@ class _RootAppState extends State<RootApp> {
 
             // Marine Investigative
             '/marine/investigative/info': (context) => const MarineInvestigativeInfoCentreDocument(),
+            '/marine/investigative/manual-sampling': (context) =>
+                marineInvestigativeManualSampling.MarineInvestigativeManualSampling(),
             '/marine/investigative/overview': (context) => marineInvestigativeOverview.OverviewScreen(),
             '/marine/investigative/entry': (context) => marineInvestigativeEntry.EntryScreen(),
             '/marine/investigative/report': (context) => marineInvestigativeReport.ReportScreen(),
@@ -370,27 +405,62 @@ class SessionAwareWrapper extends StatefulWidget {
 
 class _SessionAwareWrapperState extends State<SessionAwareWrapper> {
   bool _isDialogShowing = false;
+  // --- MODIFICATION START ---
+  // 1. Create a variable to hold the AuthProvider instance.
+  late AuthProvider _authProvider;
+  // --- MODIFICATION END ---
 
   @override
   void didChangeDependencies() {
     super.didChangeDependencies();
-    final auth = Provider.of<AuthProvider>(context);
+    // --- MODIFICATION START ---
+    // 2. Get the provider reference here and add the listener.
+    _authProvider = Provider.of<AuthProvider>(context);
+    _authProvider.addListener(_handleSessionExpired);
+    // --- MODIFICATION END ---
 
-    if (auth.isSessionExpired && !_isDialogShowing) {
-      // Use addPostFrameCallback to show dialog after the build phase.
+    // Call initial check here if needed, or rely on RootApp's check.
+    // _checkAndShowDialogIfNeeded(_authProvider.isSessionExpired);
+  }
+
+  @override
+  void dispose() {
+    // --- MODIFICATION START ---
+    // 3. Use the saved reference to remove the listener. This is safe.
+    _authProvider.removeListener(_handleSessionExpired);
+    // --- MODIFICATION END ---
+    super.dispose();
+  }
+
+  void _handleSessionExpired() {
+    // --- MODIFICATION START ---
+    // 4. Use the saved _authProvider reference.
+    _checkAndShowDialogIfNeeded(_authProvider.isSessionExpired);
+    // --- MODIFICATION END ---
+  }
+
+  void _checkAndShowDialogIfNeeded(bool isExpired) {
+    if (isExpired && !_isDialogShowing && mounted) {
       WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (mounted && !_isDialogShowing) { // Double check mounted and flag
           _showSessionExpiredDialog();
+        }
       });
+    } else if (!isExpired && _isDialogShowing && mounted) {
+      // If session becomes valid again and dialog is showing, maybe dismiss it?
+      // Or rely on user action. For now, we only trigger ON expiry.
     }
   }
 
   Future<void> _showSessionExpiredDialog() async {
+    if (!mounted) return;
+
     setState(() => _isDialogShowing = true);
     await showDialog(
       context: context,
-      barrierDismissible: false, // User must make a choice
+      barrierDismissible: false,
       builder: (BuildContext dialogContext) {
-        final auth = Provider.of<AuthProvider>(context, listen: false);
+        // Use the state's _authProvider reference, which is safe.
         return AlertDialog(
           title: const Text("Session Expired"),
           content: const Text(
@@ -399,22 +469,26 @@ class _SessionAwareWrapperState extends State<SessionAwareWrapper> {
             TextButton(
               child: const Text("Continue Offline"),
               onPressed: () {
-                Navigator.of(dialogContext).pop(); // Just close the dialog
+                Navigator.of(dialogContext).pop();
+                // Optionally: _authProvider.clearSessionExpiredFlag(); // If needed
               },
             ),
             ElevatedButton(
               child: const Text("Login Now"),
               onPressed: () {
-                // Logout clears all state and pushes to login screen via the RootApp builder
-                auth.logout();
-                Navigator.of(dialogContext).pop();
+                // --- MODIFICATION START ---
+                // 5. Use the saved reference to log out.
+                _authProvider.logout();
+                // --- MODIFICATION END ---
+                Navigator.of(dialogContext).pop(); // Close dialog first
+                // RootApp builder will handle navigation to LoginScreen
               },
             ),
           ],
         );
       },
     );
-    // Once the dialog is dismissed, reset the flag.
+    // Reset flag after dialog is dismissed
     if (mounted) {
       setState(() => _isDialogShowing = false);
     }
@@ -422,7 +496,6 @@ class _SessionAwareWrapperState extends State<SessionAwareWrapper> {
 
   @override
   Widget build(BuildContext context) {
-    // This widget just returns its child, its only job is to show the dialog.
     return widget.child;
   }
 }

lib/models/in_situ_sampling_data.dart

@@ -301,36 +301,12 @@ class InSituSamplingData {
       'npe_field_observations': npeFieldObservations,
       'npe_others_observation_remark': npeOthersObservationRemark,
       'npe_possible_source': npePossibleSource,
+      // Image paths will be added/updated by LocalStorageService during saving/updating
     };
   }
 
-  String generateTelegramAlertMessage({required bool isDataOnly}) {
-    final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
-    final stationName = selectedStation?['man_station_name'] ?? 'N/A';
-    final stationCode = selectedStation?['man_station_code'] ?? 'N/A';
-
-    final buffer = StringBuffer()
-      ..writeln('✅ *In-Situ Sample $submissionType Submitted:*')
-      ..writeln()
-      ..writeln('*Station Name & Code:* $stationName ($stationCode)')
-      ..writeln('*Date of Submission:* $samplingDate')
-      ..writeln('*Submitted by User:* $firstSamplerName')
-      ..writeln('*Sonde ID:* ${sondeId ?? "N/A"}')
-      ..writeln('*Status of Submission:* Successful');
-
-    if (distanceDifferenceInKm != null && distanceDifferenceInKm! > 0) {
-      buffer
-        ..writeln()
-        ..writeln('🔔 *Alert:*')
-        ..writeln('*Distance from station:* ${(distanceDifferenceInKm! * 1000).toStringAsFixed(0)} meters');
-
-      if (distanceDifferenceRemarks != null && distanceDifferenceRemarks!.isNotEmpty) {
-        buffer.writeln('*Remarks for distance:* $distanceDifferenceRemarks');
-      }
-    }
-
-    return buffer.toString();
-  }
+  // --- REMOVED: generateTelegramAlertMessage method ---
+  // This logic is now in MarineInSituSamplingService
 
   Map<String, String> toApiFormData() {
     final Map<String, String> map = {};

lib/models/marine_inves_manual_sampling_data.dart

@@ -1 +1,361 @@
 // lib/models/marine_inves_manual_sampling_data.dart
+
+import 'dart:io';
+import 'dart:convert'; // Added for jsonEncode
+// REMOVED: import 'package:environment_monitoring_app/models/marine_manual_npe_report_data.dart'; // No longer needed
+
+/// A data model class to hold all information for the multi-step
+/// Marine Investigative Manual Sampling form.
+class MarineInvesManualSamplingData {
+  // --- Step 1: Sampling & Station Info ---
+  String? firstSamplerName;
+  int? firstSamplerUserId;
+  Map<String, dynamic>? secondSampler;
+  String? samplingDate;
+  String? samplingTime;
+  String? samplingType;
+  String? sampleIdCode;
+
+  // --- NEW: Step 1 Station Selection ---
+  String? stationTypeSelection; // 'Existing Manual Station', 'Existing Tarball Station', 'New Location'
+
+  // For 'Existing Manual Station'
+  String? selectedManualStateName;
+  String? selectedManualCategoryName;
+  Map<String, dynamic>? selectedStation; // This is the MANUAL station
+
+  // For 'Existing Tarball Station'
+  String? selectedTarballStateName;
+  Map<String, dynamic>? selectedTarballStation;
+
+  // For 'New Location'
+  String? newStationName;
+  String? newStationCode;
+
+  // --- Common Station/Location Fields ---
+  String? stationLatitude;  // Populated from selected station OR manually entered
+  String? stationLongitude; // Populated from selected station OR manually entered
+  String? currentLatitude;
+  String? currentLongitude;
+  double? distanceDifferenceInKm;
+  String? distanceDifferenceRemarks;
+
+  // --- Step 2: Site Info & Photos ---
+  String? weather;
+  String? tideLevel;
+  String? seaCondition;
+  String? eventRemarks;
+  String? labRemarks;
+
+  File? leftLandViewImage;
+  File? rightLandViewImage;
+  File? waterFillingImage;
+  File? seawaterColorImage;
+  File? phPaperImage;
+
+  File? optionalImage1;
+  String? optionalRemark1;
+  File? optionalImage2;
+  String? optionalRemark2;
+  File? optionalImage3;
+  String? optionalRemark3;
+  File? optionalImage4;
+  String? optionalRemark4;
+
+  // --- Step 3: Data Capture ---
+  String? sondeId;
+  String? dataCaptureDate;
+  String? dataCaptureTime;
+  double? oxygenConcentration;
+  double? oxygenSaturation;
+  double? ph;
+  double? salinity;
+  double? electricalConductivity;
+  double? temperature;
+  double? tds;
+  double? turbidity;
+  double? tss;
+  double? batteryVoltage;
+
+  // --- Post-Submission Status ---
+  String? submissionStatus;
+  String? submissionMessage;
+  String? reportId; // This will be 'man_inves_id' from the DB
+
+  // REMOVED: All NPE Report Compatibility Fields (npeFieldObservations, npeOthersObservationRemark, etc.)
+
+
+  MarineInvesManualSamplingData({
+    this.samplingDate,
+    this.samplingTime,
+    this.stationTypeSelection = 'Existing Manual Station', // Default value
+  });
+
+  // REMOVED: toNpeReportData() method
+
+
+  /// Creates a single JSON object with all submission data for offline storage.
+  Map<String, dynamic> toDbJson() {
+    return {
+      // Step 1
+      'first_sampler_name': firstSamplerName,
+      'first_sampler_user_id': firstSamplerUserId,
+      'secondSampler': secondSampler,
+      'sampling_date': samplingDate,
+      'sampling_time': samplingTime,
+      'sampling_type': samplingType,
+      'sample_id_code': sampleIdCode,
+      'stationTypeSelection': stationTypeSelection,
+      'selectedManualStateName': selectedManualStateName,
+      'selectedManualCategoryName': selectedManualCategoryName,
+      'selectedStation': selectedStation,
+      'selectedTarballStateName': selectedTarballStateName,
+      'selectedTarballStation': selectedTarballStation,
+      'newStationName': newStationName,
+      'newStationCode': newStationCode,
+      'station_latitude': stationLatitude,
+      'station_longitude': stationLongitude,
+      'current_latitude': currentLatitude,
+      'current_longitude': currentLongitude,
+      'distance_difference_in_km': distanceDifferenceInKm,
+      'distance_difference_remarks': distanceDifferenceRemarks,
+      // Step 2
+      'weather': weather,
+      'tide_level': tideLevel,
+      'sea_condition': seaCondition,
+      'event_remarks': eventRemarks,
+      'lab_remarks': labRemarks,
+      'inves_optional_photo_01_remarks': optionalRemark1,
+      'inves_optional_photo_02_remarks': optionalRemark2,
+      'inves_optional_photo_03_remarks': optionalRemark3,
+      'inves_optional_photo_04_remarks': optionalRemark4,
+      // Step 3
+      'sonde_id': sondeId,
+      'data_capture_date': dataCaptureDate,
+      'data_capture_time': dataCaptureTime,
+      'oxygen_concentration': oxygenConcentration,
+      'oxygen_saturation': oxygenSaturation,
+      'ph': ph,
+      'salinity': salinity,
+      'electrical_conductivity': electricalConductivity,
+      'temperature': temperature,
+      'tds': tds,
+      'turbidity': turbidity,
+      'tss': tss,
+      'battery_voltage': batteryVoltage,
+      // Status
+      'submission_status': submissionStatus,
+      'submission_message': submissionMessage,
+      'report_id': reportId,
+      // REMOVED: NPE fields from JSON
+
+      // Image paths will be added by LocalStorageService during save
+      'inves_left_side_land_view': leftLandViewImage?.path,
+      'inves_right_side_land_view': rightLandViewImage?.path,
+      'inves_filling_water_into_sample_bottle': waterFillingImage?.path,
+      'inves_seawater_in_clear_glass_bottle': seawaterColorImage?.path,
+      'inves_examine_preservative_ph_paper': phPaperImage?.path,
+      'inves_optional_photo_01': optionalImage1?.path,
+      'inves_optional_photo_02': optionalImage2?.path,
+      'inves_optional_photo_03': optionalImage3?.path,
+      'inves_optional_photo_04': optionalImage4?.path,
+    };
+  }
+
+  /// Creates an InSituSamplingData object from a JSON map (for offline logs).
+  factory MarineInvesManualSamplingData.fromJson(Map<String, dynamic> json) {
+    double? doubleFromJson(dynamic value) {
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    int? intFromJson(dynamic value) {
+      if (value is int) return value;
+      if (value is String) return int.tryParse(value);
+      return null;
+    }
+
+    File? fileFromPath(dynamic path) {
+      // Ensure path is not null and not empty before creating File object
+      return (path is String && path.isNotEmpty) ? File(path) : null;
+    }
+
+    final data = MarineInvesManualSamplingData();
+
+    // Step 1
+    data.firstSamplerName = json['first_sampler_name'];
+    data.firstSamplerUserId = intFromJson(json['first_sampler_user_id']);
+    data.secondSampler = json['secondSampler']; // Assumes it's stored correctly as JSON Map
+    data.samplingDate = json['sampling_date'];
+    data.samplingTime = json['sampling_time'];
+    data.samplingType = json['sampling_type'];
+    data.sampleIdCode = json['sample_id_code'];
+    data.stationTypeSelection = json['stationTypeSelection'];
+    data.selectedManualStateName = json['selectedManualStateName'];
+    data.selectedManualCategoryName = json['selectedManualCategoryName'];
+    data.selectedStation = json['selectedStation']; // Assumes it's stored correctly as JSON Map
+    data.selectedTarballStateName = json['selectedTarballStateName'];
+    data.selectedTarballStation = json['selectedTarballStation']; // Assumes it's stored correctly as JSON Map
+    data.newStationName = json['newStationName'];
+    data.newStationCode = json['newStationCode'];
+    data.stationLatitude = json['station_latitude']?.toString(); // Ensure conversion to String
+    data.stationLongitude = json['station_longitude']?.toString(); // Ensure conversion to String
+    data.currentLatitude = json['current_latitude']?.toString(); // Ensure conversion to String
+    data.currentLongitude = json['current_longitude']?.toString(); // Ensure conversion to String
+    data.distanceDifferenceInKm = doubleFromJson(json['distance_difference_in_km']);
+    data.distanceDifferenceRemarks = json['distance_difference_remarks'];
+
+    // Step 2
+    data.weather = json['weather'];
+    data.tideLevel = json['tide_level'];
+    data.seaCondition = json['sea_condition'];
+    data.eventRemarks = json['event_remarks'];
+    data.labRemarks = json['lab_remarks'];
+    data.optionalRemark1 = json['inves_optional_photo_01_remarks'];
+    data.optionalRemark2 = json['inves_optional_photo_02_remarks'];
+    data.optionalRemark3 = json['inves_optional_photo_03_remarks'];
+    data.optionalRemark4 = json['inves_optional_photo_04_remarks'];
+
+    // Step 2 Images (Paths stored in JSON)
+    data.leftLandViewImage = fileFromPath(json['inves_left_side_land_view']);
+    data.rightLandViewImage = fileFromPath(json['inves_right_side_land_view']);
+    data.waterFillingImage = fileFromPath(json['inves_filling_water_into_sample_bottle']);
+    data.seawaterColorImage = fileFromPath(json['inves_seawater_in_clear_glass_bottle']);
+    data.phPaperImage = fileFromPath(json['inves_examine_preservative_ph_paper']);
+    data.optionalImage1 = fileFromPath(json['inves_optional_photo_01']);
+    data.optionalImage2 = fileFromPath(json['inves_optional_photo_02']);
+    data.optionalImage3 = fileFromPath(json['inves_optional_photo_03']);
+    data.optionalImage4 = fileFromPath(json['inves_optional_photo_04']);
+
+    // Step 3
+    data.sondeId = json['sonde_id'];
+    data.dataCaptureDate = json['data_capture_date'];
+    data.dataCaptureTime = json['data_capture_time'];
+    data.oxygenConcentration = doubleFromJson(json['oxygen_concentration']);
+    data.oxygenSaturation = doubleFromJson(json['oxygen_saturation']);
+    data.ph = doubleFromJson(json['ph']);
+    data.salinity = doubleFromJson(json['salinity']);
+    data.electricalConductivity = doubleFromJson(json['electrical_conductivity']);
+    data.temperature = doubleFromJson(json['temperature']);
+    data.tds = doubleFromJson(json['tds']);
+    data.turbidity = doubleFromJson(json['turbidity']);
+    data.tss = doubleFromJson(json['tss']);
+    data.batteryVoltage = doubleFromJson(json['battery_voltage']);
+
+    // Status
+    data.submissionStatus = json['submission_status'];
+    data.submissionMessage = json['submission_message'];
+    data.reportId = json['report_id']?.toString(); // Ensure conversion to String
+
+    // REMOVED: NPE fields from deserialization
+
+    return data;
+  }
+
+
+  /// Maps data to keys for the API submission.
+  Map<String, String> toApiFormData() {
+    final Map<String, String> map = {};
+
+    void add(String key, dynamic value) {
+      if (value != null) {
+        String stringValue;
+        if (value is double) {
+          // Handle special -999.0 value
+          if (value == -999.0) {
+            stringValue = '-999';
+          } else {
+            // Format other doubles to 5 decimal places
+            stringValue = value.toStringAsFixed(5);
+          }
+        } else {
+          // Convert other types directly to string
+          stringValue = value.toString();
+        }
+
+        // Only add if the resulting string is not empty
+        if (stringValue.isNotEmpty) {
+          map[key] = stringValue;
+        }
+      }
+    }
+
+    // Add prefix 'inves_' to all keys to match new backend endpoints
+    add('inves_date', samplingDate);
+    add('inves_time', samplingTime);
+    add('first_sampler_user_id', firstSamplerUserId);
+    add('inves_second_sampler_id', secondSampler?['user_id']);
+    add('inves_type', samplingType);
+    add('inves_sample_id_code', sampleIdCode);
+    add('inves_current_latitude', currentLatitude);
+    add('inves_current_longitude', currentLongitude);
+    add('inves_distance_difference', distanceDifferenceInKm);
+    add('inves_distance_difference_remarks', distanceDifferenceRemarks);
+
+    // --- NEW: Add station selection logic ---
+    add('inves_station_type', stationTypeSelection);
+    if (stationTypeSelection == 'Existing Manual Station') {
+      add('station_id', selectedStation?['station_id']); // Foreign key to manual stations
+      add('inves_station_code', selectedStation?['man_station_code']);
+      add('inves_station_name', selectedStation?['man_station_name']);
+    } else if (stationTypeSelection == 'Existing Tarball Station') {
+      add('tbl_station_id', selectedTarballStation?['station_id']); // Foreign key to tarball stations
+      add('inves_station_code', selectedTarballStation?['tbl_station_code']);
+      add('inves_station_name', selectedTarballStation?['tbl_station_name']);
+    } else if (stationTypeSelection == 'New Location') {
+      add('inves_new_station_name', newStationName);
+      add('inves_new_station_code', newStationCode);
+      add('inves_station_latitude', stationLatitude);   // Manually entered lat
+      add('inves_station_longitude', stationLongitude); // Manually entered lon
+    }
+    // --- END NEW ---
+
+    add('inves_weather', weather);
+    add('inves_tide_level', tideLevel);
+    add('inves_sea_condition', seaCondition);
+    add('inves_event_remark', eventRemarks);
+    add('inves_lab_remark', labRemarks);
+    add('inves_optional_photo_01_remarks', optionalRemark1);
+    add('inves_optional_photo_02_remarks', optionalRemark2);
+    add('inves_optional_photo_03_remarks', optionalRemark3);
+    add('inves_optional_photo_04_remarks', optionalRemark4);
+    add('inves_sondeID', sondeId);
+    add('data_capture_date', dataCaptureDate); // Note: No 'inves_' prefix assumed based on original model
+    add('data_capture_time', dataCaptureTime); // Note: No 'inves_' prefix assumed based on original model
+    add('inves_oxygen_conc', oxygenConcentration);
+    add('inves_oxygen_sat', oxygenSaturation);
+    add('inves_ph', ph);
+    add('inves_salinity', salinity);
+    add('inves_conductivity', electricalConductivity);
+    add('inves_temperature', temperature);
+    add('inves_tds', tds);
+    add('inves_turbidity', turbidity);
+    add('inves_tss', tss);
+    add('inves_battery_volt', batteryVoltage);
+
+    add('first_sampler_name', firstSamplerName); // For logging/display purposes on backend if needed
+
+    return map;
+  }
+
+  /// Maps image files to keys for the API submission.
+  Map<String, File?> toApiImageFiles() {
+    return {
+      // Add prefix 'inves_' to match backend expectations
+      'inves_left_side_land_view': leftLandViewImage,
+      'inves_right_side_land_view': rightLandViewImage,
+      'inves_filling_water_into_sample_bottle': waterFillingImage,
+      'inves_seawater_in_clear_glass_bottle': seawaterColorImage,
+      'inves_examine_preservative_ph_paper': phPaperImage,
+      'inves_optional_photo_01': optionalImage1,
+      'inves_optional_photo_02': optionalImage2,
+      'inves_optional_photo_03': optionalImage3,
+      'inves_optional_photo_04': optionalImage4,
+    };
+  }
+
+// --- START: REMOVED generateInvestigativeTelegramAlertMessage ---
+// This logic is now handled in MarineInvestigativeSamplingService
+// --- END: REMOVED ---
+}

lib/models/river_in_situ_sampling_data.dart

@@ -164,7 +164,23 @@ class RiverInSituSamplingData {
 
     void add(String key, dynamic value) {
       if (value != null) {
-        map[key] = value.toString();
+        String stringValue;
+        // --- START FIX: Handle -999.0 correctly ---
+        if (value is double) {
+          if (value == -999.0) {
+            stringValue = '-999';
+          } else {
+            stringValue = value.toStringAsFixed(5);
+          }
+        } else {
+          stringValue = value.toString();
+        }
+        // --- END FIX ---
+
+        // Only add non-empty values
+        if (stringValue.isNotEmpty) {
+          map[key] = stringValue;
+        }
       }
     }
 
@@ -175,7 +191,9 @@ class RiverInSituSamplingData {
     add('r_man_time', samplingTime);
     add('r_man_type', samplingType);
     add('r_man_sample_id_code', sampleIdCode);
+    // --- START FIX: Use correct key 'station_id' ---
     add('station_id', selectedStation?['station_id']);
+    // --- END FIX ---
     add('r_man_current_latitude', currentLatitude);
     add('r_man_current_longitude', currentLongitude);
     add('r_man_distance_difference', distanceDifferenceInKm);
@@ -304,43 +322,48 @@ class RiverInSituSamplingData {
     // This is a direct conversion of the model's properties to a map,
     // with keys matching the expected JSON file format.
     final data = {
-      'battery_cap': batteryVoltage,
+      // --- START FIX: Map model properties to correct db.json keys ---
+      'battery_cap': batteryVoltage == -999.0 ? null : batteryVoltage, // Handle -999
       'device_name': sondeId,
       'sampling_type': samplingType,
       'report_id': reportId,
-      'sampler_2ndname': secondSampler?['user_name'],
+      'sampler_2ndname': secondSampler?['first_name'], // Use first_name as likely user name
       'sample_state': selectedStateName,
       'station_id': selectedStation?['sampling_station_code'],
       'tech_id': firstSamplerUserId,
       'tech_name': firstSamplerName,
-      'latitude': stationLatitude,
-      'longitude': stationLongitude,
+      'latitude': stationLatitude, // Assuming station lat/lon is intended here
+      'longitude': stationLongitude, // Assuming station lat/lon is intended here
       'record_dt': '$samplingDate $samplingTime',
-      'do_mgl': oxygenConcentration,
-      'do_sat': oxygenSaturation,
-      'ph': ph,
-      'salinity': salinity,
-      'temperature': temperature,
-      'turbidity': turbidity,
-      'tds': tds,
-      'electric_conductivity': electricalConductivity,
-      'ammonia': ammonia, // MODIFIED: Added ammonia
+      'do_mgl': oxygenConcentration == -999.0 ? null : oxygenConcentration,
+      'do_sat': oxygenSaturation == -999.0 ? null : oxygenSaturation,
+      'ph': ph == -999.0 ? null : ph,
+      'salinity': salinity == -999.0 ? null : salinity,
+      'temperature': temperature == -999.0 ? null : temperature,
+      'turbidity': turbidity == -999.0 ? null : turbidity,
+      'tds': tds == -999.0 ? null : tds,
+      'electric_conductivity': electricalConductivity == -999.0 ? null : electricalConductivity,
+      'ammonia': ammonia == -999.0 ? null : ammonia,
       'flowrate': flowrateValue,
-      'odour': '', // Assuming these are not collected in this form
-      'floatable': '', // Assuming these are not collected in this form
+      'odour': '', // Not collected
+      'floatable': '', // Not collected
       'sample_id': sampleIdCode,
       'weather': weather,
       'remarks_event': eventRemarks,
       'remarks_lab': labRemarks,
+      // --- END FIX ---
     };
+    // Remove null values before encoding
+    data.removeWhere((key, value) => value == null);
     return jsonEncode(data);
   }
 
   /// Creates a JSON object for basic form info, mimicking 'river_insitu_basic_form.json'.
   String toBasicFormJson() {
     final data = {
+      // --- START FIX: Map model properties to correct form keys ---
       'tech_name': firstSamplerName,
-      'sampler_2ndname': secondSampler?['user_name'],
+      'sampler_2ndname': secondSampler?['first_name'],
       'sample_date': samplingDate,
       'sample_time': samplingTime,
       'sampling_type': samplingType,
@@ -348,39 +371,50 @@ class RiverInSituSamplingData {
       'station_id': selectedStation?['sampling_station_code'],
       'station_latitude': stationLatitude,
       'station_longitude': stationLongitude,
-      'latitude': currentLatitude,
-      'longitude': currentLongitude,
+      'latitude': currentLatitude, // Current location lat
+      'longitude': currentLongitude, // Current location lon
       'sample_id': sampleIdCode,
+      // --- END FIX ---
     };
+    // Remove null values before encoding
+    data.removeWhere((key, value) => value == null);
     return jsonEncode(data);
   }
 
   /// Creates a JSON object for sensor readings, mimicking 'river_sampling_reading.json'.
   String toReadingJson() {
     final data = {
-      'do_mgl': oxygenConcentration,
-      'do_sat': oxygenSaturation,
-      'ph': ph,
-      'salinity': salinity,
-      'temperature': temperature,
-      'turbidity': turbidity,
-      'tds': tds,
-      'electric_conductivity': electricalConductivity,
-      'ammonia': ammonia, // MODIFIED: Added ammonia
+      // --- START FIX: Map model properties to correct reading keys ---
+      'do_mgl': oxygenConcentration == -999.0 ? null : oxygenConcentration,
+      'do_sat': oxygenSaturation == -999.0 ? null : oxygenSaturation,
+      'ph': ph == -999.0 ? null : ph,
+      'salinity': salinity == -999.0 ? null : salinity,
+      'temperature': temperature == -999.0 ? null : temperature,
+      'turbidity': turbidity == -999.0 ? null : turbidity,
+      'tds': tds == -999.0 ? null : tds,
+      'electric_conductivity': electricalConductivity == -999.0 ? null : electricalConductivity,
+      'ammonia': ammonia == -999.0 ? null : ammonia,
       'flowrate': flowrateValue,
-      'date_sampling_reading': samplingDate,
-      'time_sampling_reading': samplingTime,
+      'date_sampling_reading': dataCaptureDate, // Use data capture date/time
+      'time_sampling_reading': dataCaptureTime, // Use data capture date/time
+      // --- END FIX ---
     };
+    // Remove null values before encoding
+    data.removeWhere((key, value) => value == null);
     return jsonEncode(data);
   }
 
   /// Creates a JSON object for manual info, mimicking 'river_manual_info.json'.
   String toManualInfoJson() {
     final data = {
+      // --- START FIX: Map model properties to correct manual info keys ---
       'weather': weather,
       'remarks_event': eventRemarks,
       'remarks_lab': labRemarks,
+      // --- END FIX ---
     };
+    // Remove null values before encoding
+    data.removeWhere((key, value) => value == null);
     return jsonEncode(data);
   }
 }

lib/models/river_inves_manual_sampling_data.dart

@@ -0,0 +1,520 @@
+// lib/models/river_inves_manual_sampling_data.dart
+
+import 'dart:io';
+import 'dart:convert'; // Added for jsonEncode
+
+/// Data model for the multi-step River Investigative Manual Sampling form.
+class RiverInvesManualSamplingData {
+  // --- Step 1: Sampling & Station Info ---
+  String? firstSamplerName;
+  int? firstSamplerUserId;
+  Map<String, dynamic>? secondSampler;
+  String? samplingDate;
+  String? samplingTime;
+  String? samplingType = 'Investigative'; // Defaulted for this module
+  String? sampleIdCode;
+
+  // --- NEW: Station Type Selection ---
+  String? stationTypeSelection; // 'Existing Manual Station', 'Existing Triennial Station', 'New Location'
+
+  // --- Existing Station Fields ---
+  String? selectedStateName; // Used by Manual/Triennial and as input for New
+  String? selectedCategoryName; // Potentially relevant context? Keep for now.
+  Map<String, dynamic>? selectedStation; // Holds selected MANUAL station
+  Map<String, dynamic>? selectedTriennialStation; // Holds selected TRIENNIAL station
+
+  // --- New Location Fields ---
+  String? newStateName; // Specifically for New Location state input
+  String? newBasinName;
+  String? newRiverName;
+  // *** ADDED: newStationName field ***
+  String? newStationName; // User-defined name for the new location
+  // *** END ADDED ***
+  String? newStationCode; // Optional user-defined code for new location
+
+  // --- Location Fields ---
+  String? stationLatitude; // Derived from selected station OR user input for New
+  String? stationLongitude; // Derived from selected station OR user input for New
+  String? currentLatitude;
+  String? currentLongitude;
+  double? distanceDifferenceInKm;
+  String? distanceDifferenceRemarks;
+
+  // --- Step 2: Site Info & Photos ---
+  String? weather;
+  String? eventRemarks;
+  String? labRemarks;
+
+  File? backgroundStationImage;
+  File? upstreamRiverImage;
+  File? downstreamRiverImage;
+
+  // --- Step 4: Additional Photos ---
+  File? sampleTurbidityImage;
+
+  File? optionalImage1;
+  String? optionalRemark1;
+  File? optionalImage2;
+  String? optionalRemark2;
+  File? optionalImage3;
+  String? optionalRemark3;
+  File? optionalImage4;
+  String? optionalRemark4;
+
+  // --- Step 3: Data Capture ---
+  String? sondeId;
+  String? dataCaptureDate;
+  String? dataCaptureTime;
+  double? oxygenConcentration;
+  double? oxygenSaturation;
+  double? ph;
+  double? salinity;
+  double? electricalConductivity;
+  double? temperature;
+  double? tds;
+  double? turbidity;
+  double? ammonia; // Replaced tss
+  double? batteryVoltage;
+
+  // Flowrate properties (same as In-Situ)
+  String? flowrateMethod; // 'Surface Drifter', 'Flowmeter', 'NA'
+  double? flowrateSurfaceDrifterHeight;
+  double? flowrateSurfaceDrifterDistance;
+  String? flowrateSurfaceDrifterTimeFirst;
+  String? flowrateSurfaceDrifterTimeLast;
+  double? flowrateValue;
+
+  // --- Post-Submission Status ---
+  String? submissionStatus;
+  String? submissionMessage;
+  String? reportId; // Assuming the API returns an ID (e.g., r_inv_id)
+
+  RiverInvesManualSamplingData({
+    this.samplingDate,
+    this.samplingTime,
+  });
+
+  // Helper to get the determined station code regardless of type
+  String? getDeterminedStationCode() {
+    if (stationTypeSelection == 'Existing Manual Station') {
+      return selectedStation?['sampling_station_code'];
+    } else if (stationTypeSelection == 'Existing Triennial Station') {
+      return selectedTriennialStation?['triennial_station_code'];
+    } else if (stationTypeSelection == 'New Location') {
+      return newStationCode; // Use user-provided code or null
+    }
+    return null;
+  }
+
+  // Helper to get determined State Name
+  String? getDeterminedStateName() {
+    if (stationTypeSelection == 'Existing Manual Station' || stationTypeSelection == 'Existing Triennial Station') {
+      return selectedStateName;
+    } else if (stationTypeSelection == 'New Location') {
+      return newStateName;
+    }
+    return null;
+  }
+
+  // Helper to get determined River Name
+  String? getDeterminedRiverName() {
+    if (stationTypeSelection == 'Existing Manual Station') {
+      return selectedStation?['sampling_river'];
+    } else if (stationTypeSelection == 'Existing Triennial Station') {
+      return selectedTriennialStation?['triennial_river'];
+    } else if (stationTypeSelection == 'New Location') {
+      return newRiverName;
+    }
+    return null;
+  }
+
+  // Helper to get determined Basin Name
+  String? getDeterminedBasinName() {
+    if (stationTypeSelection == 'Existing Manual Station') {
+      return selectedStation?['sampling_basin'];
+    } else if (stationTypeSelection == 'Existing Triennial Station') {
+      return selectedTriennialStation?['triennial_basin'];
+    } else if (stationTypeSelection == 'New Location') {
+      return newBasinName;
+    }
+    return null;
+  }
+
+  // *** ADDED: getDeterminedStationName helper ***
+  String? getDeterminedStationName() {
+    // This combines River Name for existing stations or the New Station Name
+    if (stationTypeSelection == 'Existing Manual Station') {
+      return selectedStation?['sampling_river']; // Use river name as station name contextually
+    } else if (stationTypeSelection == 'Existing Triennial Station') {
+      return selectedTriennialStation?['triennial_river']; // Use river name as station name contextually
+    } else if (stationTypeSelection == 'New Location') {
+      return newStationName; // Use the specific name given for the new location
+    }
+    return null;
+  }
+  // *** END ADDED ***
+
+
+  factory RiverInvesManualSamplingData.fromJson(Map<String, dynamic> json) {
+    File? fileFromJson(dynamic path) {
+      return (path is String && path.isNotEmpty) ? File(path) : null;
+    }
+
+    double? doubleFromJson(dynamic value) {
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    int? intFromJson(dynamic value) {
+      if (value is int) return value;
+      if (value is String) return int.tryParse(value);
+      return null;
+    }
+
+    // Adapted from RiverInSituSamplingData.fromJson
+    return RiverInvesManualSamplingData()
+    // Step 1
+      ..firstSamplerName = json['firstSamplerName']
+      ..firstSamplerUserId = intFromJson(json['firstSamplerUserId'])
+      ..secondSampler = json['secondSampler']
+      ..samplingDate = json['samplingDate']
+      ..samplingTime = json['samplingTime']
+      ..samplingType = json['samplingType'] ?? 'Investigative'
+      ..sampleIdCode = json['sampleIdCode']
+      ..stationTypeSelection = json['stationTypeSelection']
+      ..selectedStateName = json['selectedStateName'] // State for existing stations
+      ..selectedCategoryName = json['selectedCategoryName']
+      ..selectedStation = json['selectedStation'] // Manual
+      ..selectedTriennialStation = json['selectedTriennialStation'] // Triennial
+      ..newStateName = json['newStateName'] // New Location state
+      ..newBasinName = json['newBasinName']
+      ..newRiverName = json['newRiverName']
+      ..newStationName = json['newStationName'] // Load newStationName
+      ..newStationCode = json['newStationCode']
+      ..stationLatitude = json['stationLatitude']
+      ..stationLongitude = json['stationLongitude']
+      ..currentLatitude = json['currentLatitude']?.toString()
+      ..currentLongitude = json['currentLongitude']?.toString()
+      ..distanceDifferenceInKm = doubleFromJson(json['distanceDifferenceInKm'])
+      ..distanceDifferenceRemarks = json['distanceDifferenceRemarks']
+    // Step 2
+      ..weather = json['weather']
+      ..eventRemarks = json['eventRemarks']
+      ..labRemarks = json['labRemarks']
+      ..backgroundStationImage = fileFromJson(json['backgroundStationImage'])
+      ..upstreamRiverImage = fileFromJson(json['upstreamRiverImage'])
+      ..downstreamRiverImage = fileFromJson(json['downstreamRiverImage'])
+    // Step 4
+      ..sampleTurbidityImage = fileFromJson(json['sampleTurbidityImage'])
+      ..optionalImage1 = fileFromJson(json['optionalImage1'])
+      ..optionalRemark1 = json['optionalRemark1']
+      ..optionalImage2 = fileFromJson(json['optionalImage2'])
+      ..optionalRemark2 = json['optionalRemark2']
+      ..optionalImage3 = fileFromJson(json['optionalImage3'])
+      ..optionalRemark3 = json['optionalRemark3']
+      ..optionalImage4 = fileFromJson(json['optionalImage4'])
+      ..optionalRemark4 = json['optionalRemark4']
+    // Step 3
+      ..sondeId = json['sondeId']
+      ..dataCaptureDate = json['dataCaptureDate']
+      ..dataCaptureTime = json['dataCaptureTime']
+      ..oxygenConcentration = doubleFromJson(json['oxygenConcentration'])
+      ..oxygenSaturation = doubleFromJson(json['oxygenSaturation'])
+      ..ph = doubleFromJson(json['ph'])
+      ..salinity = doubleFromJson(json['salinity'])
+      ..electricalConductivity = doubleFromJson(json['electricalConductivity'])
+      ..temperature = doubleFromJson(json['temperature'])
+      ..tds = doubleFromJson(json['tds'])
+      ..turbidity = doubleFromJson(json['turbidity'])
+      ..ammonia = doubleFromJson(json['ammonia'])
+      ..batteryVoltage = doubleFromJson(json['batteryVoltage'])
+      ..flowrateMethod = json['flowrateMethod']
+      ..flowrateSurfaceDrifterHeight = doubleFromJson(json['flowrateSurfaceDrifterHeight'])
+      ..flowrateSurfaceDrifterDistance = doubleFromJson(json['flowrateSurfaceDrifterDistance'])
+      ..flowrateSurfaceDrifterTimeFirst = json['flowrateSurfaceDrifterTimeFirst']
+      ..flowrateSurfaceDrifterTimeLast = json['flowrateSurfaceDrifterTimeLast']
+      ..flowrateValue = doubleFromJson(json['flowrateValue'])
+    // Status
+      ..submissionStatus = json['submissionStatus']
+      ..submissionMessage = json['submissionMessage']
+      ..reportId = json['reportId']?.toString();
+  }
+
+  /// Converts the data model into a Map<String, dynamic> for saving/logging locally.
+  Map<String, dynamic> toMap() {
+    return {
+      'firstSamplerName': firstSamplerName,
+      'firstSamplerUserId': firstSamplerUserId,
+      'secondSampler': secondSampler,
+      'samplingDate': samplingDate,
+      'samplingTime': samplingTime,
+      'samplingType': samplingType,
+      'sampleIdCode': sampleIdCode,
+      'stationTypeSelection': stationTypeSelection,
+      'selectedStateName': selectedStateName,
+      'selectedCategoryName': selectedCategoryName,
+      'selectedStation': selectedStation, // Manual
+      'selectedTriennialStation': selectedTriennialStation, // Triennial
+      'newStateName': newStateName, // New Loc
+      'newBasinName': newBasinName,
+      'newRiverName': newRiverName,
+      'newStationName': newStationName, // Include newStationName
+      'newStationCode': newStationCode,
+      'stationLatitude': stationLatitude,
+      'stationLongitude': stationLongitude,
+      'currentLatitude': currentLatitude,
+      'currentLongitude': currentLongitude,
+      'distanceDifferenceInKm': distanceDifferenceInKm,
+      'distanceDifferenceRemarks': distanceDifferenceRemarks,
+      'weather': weather,
+      'eventRemarks': eventRemarks,
+      'labRemarks': labRemarks,
+      'backgroundStationImage': backgroundStationImage?.path,
+      'upstreamRiverImage': upstreamRiverImage?.path,
+      'downstreamRiverImage': downstreamRiverImage?.path,
+      'sampleTurbidityImage': sampleTurbidityImage?.path,
+      'optionalImage1': optionalImage1?.path,
+      'optionalRemark1': optionalRemark1,
+      'optionalImage2': optionalImage2?.path,
+      'optionalRemark2': optionalRemark2,
+      'optionalImage3': optionalImage3?.path,
+      'optionalRemark3': optionalRemark3,
+      'optionalImage4': optionalImage4?.path,
+      'optionalRemark4': optionalRemark4,
+      'sondeId': sondeId,
+      'dataCaptureDate': dataCaptureDate,
+      'dataCaptureTime': dataCaptureTime,
+      'oxygenConcentration': oxygenConcentration,
+      'oxygenSaturation': oxygenSaturation,
+      'ph': ph,
+      'salinity': salinity,
+      'electricalConductivity': electricalConductivity,
+      'temperature': temperature,
+      'tds': tds,
+      'turbidity': turbidity,
+      'ammonia': ammonia,
+      'batteryVoltage': batteryVoltage,
+      'flowrateMethod': flowrateMethod,
+      'flowrateSurfaceDrifterHeight': flowrateSurfaceDrifterHeight,
+      'flowrateSurfaceDrifterDistance': flowrateSurfaceDrifterDistance,
+      'flowrateSurfaceDrifterTimeFirst': flowrateSurfaceDrifterTimeFirst,
+      'flowrateSurfaceDrifterTimeLast': flowrateSurfaceDrifterTimeLast,
+      'flowrateValue': flowrateValue,
+      'submissionStatus': submissionStatus,
+      'submissionMessage': submissionMessage,
+      'reportId': reportId,
+    };
+  }
+
+
+  /// Converts the data model into a Map<String, String> for the API form data.
+  /// Keys should match the expected API endpoint fields for Investigative sampling.
+  Map<String, String> toApiFormData() {
+    final Map<String, String> map = {};
+
+    void add(String key, dynamic value) {
+      if (value != null) {
+        String stringValue;
+        if (value is double) {
+          stringValue = (value == -999.0) ? '-999' : value.toStringAsFixed(5);
+        } else {
+          stringValue = value.toString();
+        }
+        if (stringValue.isNotEmpty) {
+          map[key] = stringValue;
+        }
+      }
+    }
+
+    // Sampler & Time Info (Assuming same API keys as manual)
+    add('first_sampler_user_id', firstSamplerUserId);
+    add('r_inv_second_sampler_id', secondSampler?['user_id']); // Prefixed inv?
+    add('r_inv_date', samplingDate);
+    add('r_inv_time', samplingTime);
+    add('r_inv_type', samplingType); // Should be 'Investigative'
+    add('r_inv_sample_id_code', sampleIdCode);
+
+    // Station Info (Conditional)
+    add('r_inv_station_type', stationTypeSelection);
+    if (stationTypeSelection == 'Existing Manual Station') {
+      add('station_id', selectedStation?['station_id']); // Assuming API wants the numeric ID
+      add('r_inv_station_code', selectedStation?['sampling_station_code']); // Add code for display/logging if needed
+    } else if (stationTypeSelection == 'Existing Triennial Station') {
+      add('triennial_station_id', selectedTriennialStation?['station_id']); // Assuming a different key
+      add('r_inv_station_code', selectedTriennialStation?['triennial_station_code']);
+    } else if (stationTypeSelection == 'New Location') {
+      add('r_inv_new_state_name', newStateName);
+      add('r_inv_new_basin_name', newBasinName);
+      add('r_inv_new_river_name', newRiverName);
+      add('r_inv_new_station_name', newStationName); // Include newStationName
+      add('r_inv_new_station_code', newStationCode); // Optional code
+      add('r_inv_station_latitude', stationLatitude); // Use the captured/entered lat/lon
+      add('r_inv_station_longitude', stationLongitude);
+    }
+
+    // Location Verification (Assuming same keys)
+    add('r_inv_current_latitude', currentLatitude);
+    add('r_inv_current_longitude', currentLongitude);
+    add('r_inv_distance_difference', distanceDifferenceInKm);
+    add('r_inv_distance_difference_remarks', distanceDifferenceRemarks);
+
+    // Site Info (Assuming same keys)
+    add('r_inv_weather', weather);
+    add('r_inv_event_remark', eventRemarks);
+    add('r_inv_lab_remark', labRemarks);
+
+    // Optional Remarks (Assuming same keys)
+    add('r_inv_optional_photo_01_remarks', optionalRemark1);
+    add('r_inv_optional_photo_02_remarks', optionalRemark2);
+    add('r_inv_optional_photo_03_remarks', optionalRemark3);
+    add('r_inv_optional_photo_04_remarks', optionalRemark4);
+
+    // Parameters (Assuming same keys)
+    add('r_inv_sondeID', sondeId);
+    add('data_capture_date', dataCaptureDate); // Reuse generic keys?
+    add('data_capture_time', dataCaptureTime); // Reuse generic keys?
+    add('r_inv_oxygen_conc', oxygenConcentration);
+    add('r_inv_oxygen_sat', oxygenSaturation);
+    add('r_inv_ph', ph);
+    add('r_inv_salinity', salinity);
+    add('r_inv_conductivity', electricalConductivity);
+    add('r_inv_temperature', temperature);
+    add('r_inv_tds', tds);
+    add('r_inv_turbidity', turbidity);
+    add('r_inv_ammonia', ammonia);
+    add('r_inv_battery_volt', batteryVoltage);
+
+    // Flowrate (Assuming same keys)
+    add('r_inv_flowrate_method', flowrateMethod);
+    add('r_inv_flowrate_sd_height', flowrateSurfaceDrifterHeight);
+    add('r_inv_flowrate_sd_distance', flowrateSurfaceDrifterDistance);
+    add('r_inv_flowrate_sd_time_first', flowrateSurfaceDrifterTimeFirst);
+    add('r_inv_flowrate_sd_time_last', flowrateSurfaceDrifterTimeLast);
+    add('r_inv_flowrate_value', flowrateValue);
+
+    // Additional data that might be useful for display or if API needs it redundantly
+    add('first_sampler_name', firstSamplerName);
+    add('determined_state_name', getDeterminedStateName()); // Add determined values
+    add('determined_basin_name', getDeterminedBasinName());
+    add('determined_river_name', getDeterminedRiverName());
+    add('determined_station_name', getDeterminedStationName()); // Add determined station name
+
+
+    return map;
+  }
+
+  /// Converts the image properties into a Map<String, File?> for the multipart API request.
+  /// Keys should match the expected API endpoint fields for Investigative images.
+  Map<String, File?> toApiImageFiles() {
+    // Assuming same keys as manual, but prefixed with r_inv_?
+    return {
+      'r_inv_background_station': backgroundStationImage,
+      'r_inv_upstream_river': upstreamRiverImage,
+      'r_inv_downstream_river': downstreamRiverImage,
+      'r_inv_sample_turbidity': sampleTurbidityImage,
+      'r_inv_optional_photo_01': optionalImage1,
+      'r_inv_optional_photo_02': optionalImage2,
+      'r_inv_optional_photo_03': optionalImage3,
+      'r_inv_optional_photo_04': optionalImage4,
+    };
+  }
+
+  /// Creates a single JSON object for FTP 'db.json', mimicking River In-Situ structure.
+  String toDbJson() {
+    final data = {
+      'battery_cap': batteryVoltage == -999.0 ? null : batteryVoltage,
+      'device_name': sondeId,
+      'sampling_type': samplingType, // 'Investigative'
+      'report_id': reportId,
+      'sampler_2ndname': secondSampler?['first_name'],
+      'sample_state': getDeterminedStateName(), // Use determined state
+      'station_id': getDeterminedStationCode(), // Use determined code
+      'tech_id': firstSamplerUserId,
+      'tech_name': firstSamplerName,
+      'latitude': stationLatitude, // Use captured/selected station lat
+      'longitude': stationLongitude, // Use captured/selected station lon
+      'record_dt': '$samplingDate $samplingTime',
+      'do_mgl': oxygenConcentration == -999.0 ? null : oxygenConcentration,
+      'do_sat': oxygenSaturation == -999.0 ? null : oxygenSaturation,
+      'ph': ph == -999.0 ? null : ph,
+      'salinity': salinity == -999.0 ? null : salinity,
+      'temperature': temperature == -999.0 ? null : temperature,
+      'turbidity': turbidity == -999.0 ? null : turbidity,
+      'tds': tds == -999.0 ? null : tds,
+      'electric_conductivity': electricalConductivity == -999.0 ? null : electricalConductivity,
+      'ammonia': ammonia == -999.0 ? null : ammonia,
+      'flowrate': flowrateValue,
+      'odour': '', // Not collected
+      'floatable': '', // Not collected
+      'sample_id': sampleIdCode,
+      'weather': weather,
+      'remarks_event': eventRemarks,
+      'remarks_lab': labRemarks,
+      // --- Add Investigative Specific fields if needed by FTP structure ---
+      'station_type': stationTypeSelection, // e.g., 'New Location'
+      'new_basin': stationTypeSelection == 'New Location' ? newBasinName : null,
+      'new_river': stationTypeSelection == 'New Location' ? newRiverName : null,
+      'new_station_name': stationTypeSelection == 'New Location' ? newStationName : null, // Include newStationName
+    };
+    data.removeWhere((key, value) => value == null);
+    return jsonEncode(data);
+  }
+
+  /// Creates JSON for FTP 'river_inves_basic_form.json' (mimicking In-Situ).
+  String toBasicFormJson() {
+    final data = {
+      'tech_name': firstSamplerName,
+      'sampler_2ndname': secondSampler?['first_name'],
+      'sample_date': samplingDate,
+      'sample_time': samplingTime,
+      'sampling_type': samplingType, // 'Investigative'
+      'sample_state': getDeterminedStateName(),
+      'station_id': getDeterminedStationCode(),
+      'station_latitude': stationLatitude,
+      'station_longitude': stationLongitude,
+      'latitude': currentLatitude, // Current location lat
+      'longitude': currentLongitude, // Current location lon
+      'sample_id': sampleIdCode,
+      // --- Add Investigative Specific fields if needed ---
+      'station_type': stationTypeSelection,
+      'new_basin': stationTypeSelection == 'New Location' ? newBasinName : null,
+      'new_river': stationTypeSelection == 'New Location' ? newRiverName : null,
+      'new_station_name': stationTypeSelection == 'New Location' ? newStationName : null, // Include newStationName
+    };
+    data.removeWhere((key, value) => value == null);
+    return jsonEncode(data);
+  }
+
+  /// Creates JSON for FTP 'river_inves_reading.json' (mimicking In-Situ).
+  String toReadingJson() {
+    final data = {
+      'do_mgl': oxygenConcentration == -999.0 ? null : oxygenConcentration,
+      'do_sat': oxygenSaturation == -999.0 ? null : oxygenSaturation,
+      'ph': ph == -999.0 ? null : ph,
+      'salinity': salinity == -999.0 ? null : salinity,
+      'temperature': temperature == -999.0 ? null : temperature,
+      'turbidity': turbidity == -999.0 ? null : turbidity,
+      'tds': tds == -999.0 ? null : tds,
+      'electric_conductivity': electricalConductivity == -999.0 ? null : electricalConductivity,
+      'ammonia': ammonia == -999.0 ? null : ammonia,
+      'flowrate': flowrateValue,
+      'date_sampling_reading': dataCaptureDate,
+      'time_sampling_reading': dataCaptureTime,
+    };
+    data.removeWhere((key, value) => value == null);
+    return jsonEncode(data);
+  }
+
+  /// Creates JSON for FTP 'river_inves_manual_info.json' (mimicking In-Situ).
+  String toManualInfoJson() {
+    final data = {
+      'weather': weather,
+      'remarks_event': eventRemarks,
+      'remarks_lab': labRemarks,
+    };
+    data.removeWhere((key, value) => value == null);
+    return jsonEncode(data);
+  }
+
+}

lib/models/river_manual_triennial_sampling_data.dart

@@ -1,8 +1,9 @@
 // lib/models/river_manual_triennial_sampling_data.dart
 
 import 'dart:io';
-import 'dart:convert';
+import 'dart:convert'; // Added for jsonEncode
 
+/// Data model for the River Manual Triennial Sampling form.
 class RiverManualTriennialSamplingData {
   // --- Step 1: Sampling & Station Info ---
   String? firstSamplerName;
@@ -14,8 +15,7 @@ class RiverManualTriennialSamplingData {
   String? sampleIdCode;
 
   String? selectedStateName;
-  String? selectedCategoryName;
-  Map<String, dynamic>? selectedStation;
+  Map<String, dynamic>? selectedStation; // Triennial stations don't have categories
 
   String? stationLatitude;
   String? stationLongitude;
@@ -45,7 +45,7 @@ class RiverManualTriennialSamplingData {
   File? optionalImage4;
   String? optionalRemark4;
 
-  // --- Step 3: Data Capture ---
+  // --- Step 3: Data Capture (Mirrors River In-Situ for now) ---
   String? sondeId;
   String? dataCaptureDate;
   String? dataCaptureTime;
@@ -57,10 +57,9 @@ class RiverManualTriennialSamplingData {
   double? temperature;
   double? tds;
   double? turbidity;
-  double? ammonia;
+  double? ammonia; // Replaced tss with ammonia
   double? batteryVoltage;
 
-  // --- ADDED: Missing flowrate properties ---
   String? flowrateMethod;
   double? flowrateSurfaceDrifterHeight;
   double? flowrateSurfaceDrifterDistance;
@@ -76,37 +75,131 @@ class RiverManualTriennialSamplingData {
   RiverManualTriennialSamplingData({
     this.samplingDate,
     this.samplingTime,
+    this.samplingType = 'Triennial', // Default for this form
   });
 
+  factory RiverManualTriennialSamplingData.fromJson(Map<String, dynamic> json) {
+    File? fileFromJson(dynamic path) {
+      return (path is String && path.isNotEmpty) ? File(path) : null;
+    }
+
+    double? doubleFromJson(dynamic value) {
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    int? intFromJson(dynamic value) {
+      if (value is int) return value;
+      if (value is String) return int.tryParse(value);
+      return null;
+    }
+
+    return RiverManualTriennialSamplingData()
+      ..firstSamplerName = json['firstSamplerName'] ?? json['first_sampler_name']
+      ..firstSamplerUserId = intFromJson(json['firstSamplerUserId'] ?? json['first_sampler_user_id'])
+      ..secondSampler = json['secondSampler']
+      ..samplingDate = json['samplingDate'] ?? json['r_tri_date']
+      ..samplingTime = json['samplingTime'] ?? json['r_tri_time']
+      ..samplingType = json['samplingType'] ?? json['r_tri_type']
+      ..sampleIdCode = json['sampleIdCode'] ?? json['r_tri_sample_id_code']
+      ..selectedStateName = json['selectedStateName']
+      ..selectedStation = json['selectedStation']
+      ..stationLatitude = json['stationLatitude']
+      ..stationLongitude = json['stationLongitude']
+      ..currentLatitude = (json['currentLatitude'] ?? json['r_tri_current_latitude'])?.toString()
+      ..currentLongitude = (json['currentLongitude'] ?? json['r_tri_current_longitude'])?.toString()
+      ..distanceDifferenceInKm = doubleFromJson(json['distanceDifferenceInKm'] ?? json['r_tri_distance_difference'])
+      ..distanceDifferenceRemarks = json['distanceDifferenceRemarks'] ?? json['r_tri_distance_difference_remarks']
+      ..weather = json['weather'] ?? json['r_tri_weather']
+      ..eventRemarks = json['eventRemarks'] ?? json['r_tri_event_remark']
+      ..labRemarks = json['labRemarks'] ?? json['r_tri_lab_remark']
+      ..sondeId = json['sondeId'] ?? json['r_tri_sondeID']
+      ..dataCaptureDate = json['dataCaptureDate'] ?? json['data_capture_date']
+      ..dataCaptureTime = json['dataCaptureTime'] ?? json['data_capture_time']
+      ..oxygenConcentration = doubleFromJson(json['oxygenConcentration'] ?? json['r_tri_oxygen_conc'])
+      ..oxygenSaturation = doubleFromJson(json['oxygenSaturation'] ?? json['r_tri_oxygen_sat'])
+      ..ph = doubleFromJson(json['ph'] ?? json['r_tri_ph'])
+      ..salinity = doubleFromJson(json['salinity'] ?? json['r_tri_salinity'])
+      ..electricalConductivity = doubleFromJson(json['electricalConductivity'] ?? json['r_tri_conductivity'])
+      ..temperature = doubleFromJson(json['temperature'] ?? json['r_tri_temperature'])
+      ..tds = doubleFromJson(json['tds'] ?? json['r_tri_tds'])
+      ..turbidity = doubleFromJson(json['turbidity'] ?? json['r_tri_turbidity'])
+      ..ammonia = doubleFromJson(json['ammonia'] ?? json['r_tri_ammonia'])
+      ..batteryVoltage = doubleFromJson(json['batteryVoltage'] ?? json['r_tri_battery_volt'])
+      ..optionalRemark1 = json['optionalRemark1'] ?? json['r_tri_optional_photo_01_remarks']
+      ..optionalRemark2 = json['optionalRemark2'] ?? json['r_tri_optional_photo_02_remarks']
+      ..optionalRemark3 = json['optionalRemark3'] ?? json['r_tri_optional_photo_03_remarks']
+      ..optionalRemark4 = json['optionalRemark4'] ?? json['r_tri_optional_photo_04_remarks']
+      ..backgroundStationImage = fileFromJson(json['backgroundStationImage'] ?? json['r_tri_background_station'])
+      ..upstreamRiverImage = fileFromJson(json['upstreamRiverImage'] ?? json['r_tri_upstream_river'])
+      ..downstreamRiverImage = fileFromJson(json['downstreamRiverImage'] ?? json['r_tri_downstream_river'])
+      ..sampleTurbidityImage = fileFromJson(json['sampleTurbidityImage'] ?? json['r_tri_sample_turbidity'])
+      ..optionalImage1 = fileFromJson(json['optionalImage1'] ?? json['r_tri_optional_photo_01'])
+      ..optionalImage2 = fileFromJson(json['optionalImage2'] ?? json['r_tri_optional_photo_02'])
+      ..optionalImage3 = fileFromJson(json['optionalImage3'] ?? json['r_tri_optional_photo_03'])
+      ..optionalImage4 = fileFromJson(json['optionalImage4'] ?? json['r_tri_optional_photo_04'])
+      ..flowrateMethod = json['flowrateMethod'] ?? json['r_tri_flowrate_method']
+      ..flowrateSurfaceDrifterHeight = doubleFromJson(json['flowrateSurfaceDrifterHeight'] ?? json['r_tri_flowrate_sd_height'])
+      ..flowrateSurfaceDrifterDistance = doubleFromJson(json['flowrateSurfaceDrifterDistance'] ?? json['r_tri_flowrate_sd_distance'])
+      ..flowrateSurfaceDrifterTimeFirst = json['flowrateSurfaceDrifterTimeFirst'] ?? json['r_tri_flowrate_sd_time_first']
+      ..flowrateSurfaceDrifterTimeLast = json['flowrateSurfaceDrifterTimeLast'] ?? json['r_tri_flowrate_sd_time_last']
+      ..flowrateValue = doubleFromJson(json['flowrateValue'] ?? json['r_tri_flowrate_value'])
+      ..submissionStatus = json['submissionStatus']
+      ..submissionMessage = json['submissionMessage']
+      ..reportId = json['reportId']?.toString();
+  }
+
+
+  /// Converts the data model into a Map<String, String> for the API form data.
   Map<String, String> toApiFormData() {
     final Map<String, String> map = {};
 
     void add(String key, dynamic value) {
       if (value != null) {
-        map[key] = value.toString();
+        String stringValue;
+        if (value is double) {
+          if (value == -999.0) {
+            stringValue = '-999';
+          } else {
+            stringValue = value.toStringAsFixed(5);
+          }
+        } else {
+          stringValue = value.toString();
+        }
+        if (stringValue.isNotEmpty) {
+          map[key] = stringValue;
+        }
       }
     }
 
+    // Step 1 Data
     add('first_sampler_user_id', firstSamplerUserId);
     add('r_tri_second_sampler_id', secondSampler?['user_id']);
     add('r_tri_date', samplingDate);
     add('r_tri_time', samplingTime);
     add('r_tri_type', samplingType);
     add('r_tri_sample_id_code', sampleIdCode);
-    add('station_id', selectedStation?['station_id']);
+    add('station_id', selectedStation?['station_id']); // Ensure this is the correct foreign key
     add('r_tri_current_latitude', currentLatitude);
     add('r_tri_current_longitude', currentLongitude);
     add('r_tri_distance_difference', distanceDifferenceInKm);
     add('r_tri_distance_difference_remarks', distanceDifferenceRemarks);
+
+    // Step 2 Data
     add('r_tri_weather', weather);
     add('r_tri_event_remark', eventRemarks);
     add('r_tri_lab_remark', labRemarks);
+
+    // Step 4 Data
     add('r_tri_optional_photo_01_remarks', optionalRemark1);
     add('r_tri_optional_photo_02_remarks', optionalRemark2);
     add('r_tri_optional_photo_03_remarks', optionalRemark3);
     add('r_tri_optional_photo_04_remarks', optionalRemark4);
+
+    // Step 3 Data
     add('r_tri_sondeID', sondeId);
-    add('data_capture_date', dataCaptureDate);
+    add('data_capture_date', dataCaptureDate); // Note: Keys likely shared with in-situ for capture time
     add('data_capture_time', dataCaptureTime);
     add('r_tri_oxygen_conc', oxygenConcentration);
     add('r_tri_oxygen_sat', oxygenSaturation);
@@ -124,13 +217,17 @@ class RiverManualTriennialSamplingData {
     add('r_tri_flowrate_sd_time_first', flowrateSurfaceDrifterTimeFirst);
     add('r_tri_flowrate_sd_time_last', flowrateSurfaceDrifterTimeLast);
     add('r_tri_flowrate_value', flowrateValue);
+
+    // Additional data for display or logging
     add('first_sampler_name', firstSamplerName);
     add('r_tri_station_code', selectedStation?['sampling_station_code']);
     add('r_tri_station_name', selectedStation?['sampling_river']);
 
+
     return map;
   }
 
+  /// Converts the image properties into a Map<String, File?> for the multipart API request.
   Map<String, File?> toApiImageFiles() {
     return {
       'r_tri_background_station': backgroundStationImage,
@@ -144,7 +241,7 @@ class RiverManualTriennialSamplingData {
     };
   }
 
-  // --- ADDED: Missing toMap() method ---
+  /// Converts the data model into a Map suitable for saving to local storage or DB log.
   Map<String, dynamic> toMap() {
     return {
       'firstSamplerName': firstSamplerName,
@@ -155,7 +252,6 @@ class RiverManualTriennialSamplingData {
       'samplingType': samplingType,
       'sampleIdCode': sampleIdCode,
       'selectedStateName': selectedStateName,
-      'selectedCategoryName': selectedCategoryName,
       'selectedStation': selectedStation,
       'stationLatitude': stationLatitude,
       'stationLongitude': stationLongitude,
@@ -202,4 +298,40 @@ class RiverManualTriennialSamplingData {
       'reportId': reportId,
     };
   }
+
+  /// Creates a single JSON object with all submission data, mimicking 'db.json'
+  String toDbJson() {
+    final data = {
+      'battery_cap': batteryVoltage == -999.0 ? null : batteryVoltage,
+      'device_name': sondeId,
+      'sampling_type': samplingType,
+      'report_id': reportId,
+      'sampler_2ndname': secondSampler?['first_name'],
+      'sample_state': selectedStateName,
+      'station_id': selectedStation?['sampling_station_code'],
+      'tech_id': firstSamplerUserId,
+      'tech_name': firstSamplerName,
+      'latitude': stationLatitude,
+      'longitude': stationLongitude,
+      'record_dt': '$samplingDate $samplingTime',
+      'do_mgl': oxygenConcentration == -999.0 ? null : oxygenConcentration,
+      'do_sat': oxygenSaturation == -999.0 ? null : oxygenSaturation,
+      'ph': ph == -999.0 ? null : ph,
+      'salinity': salinity == -999.0 ? null : salinity,
+      'temperature': temperature == -999.0 ? null : temperature,
+      'turbidity': turbidity == -999.0 ? null : turbidity,
+      'tds': tds == -999.0 ? null : tds,
+      'electric_conductivity': electricalConductivity == -999.0 ? null : electricalConductivity,
+      'ammonia': ammonia == -999.0 ? null : ammonia,
+      'flowrate': flowrateValue,
+      'odour': '', // Not collected
+      'floatable': '', // Not collected
+      'sample_id': sampleIdCode,
+      'weather': weather,
+      'remarks_event': eventRemarks,
+      'remarks_lab': labRemarks,
+    };
+    data.removeWhere((key, value) => value == null);
+    return jsonEncode(data);
+  }
 }

lib/models/tarball_data.dart

@@ -54,7 +54,7 @@ class TarballSamplingData {
     npeData.firstSamplerUserId = firstSamplerUserId;
     npeData.eventDate = samplingDate;
     npeData.eventTime = samplingTime;
-    npeData.selectedStation = selectedStation;
+    npeData.selectedStation = selectedStation; // Pass the whole station map
     npeData.latitude = currentLatitude;
     npeData.longitude = currentLongitude;
     npeData.stateName = selectedStateName;
@@ -62,40 +62,29 @@ class TarballSamplingData {
     // Pre-tick the relevant observation for a tarball event.
     npeData.fieldObservations['Observation of tar balls'] = true;
 
+    // Transfer images
+    final availableImages = [
+      leftCoastalViewImage,
+      rightCoastalViewImage,
+      verticalLinesImage,
+      horizontalLineImage,
+      optionalImage1,
+      optionalImage2,
+      optionalImage3,
+      optionalImage4,
+    ].where((img) => img != null).cast<File>().toList();
+
+    if (availableImages.isNotEmpty) npeData.image1 = availableImages[0];
+    if (availableImages.length > 1) npeData.image2 = availableImages[1];
+    if (availableImages.length > 2) npeData.image3 = availableImages[2];
+    if (availableImages.length > 3) npeData.image4 = availableImages[3];
+
+
     return npeData;
   }
 
-  /// Generates a formatted Telegram alert message for successful submissions.
-  String generateTelegramAlertMessage({required bool isDataOnly}) {
-    final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
-    final stationName = selectedStation?['tbl_station_name'] ?? 'N/A';
-    final stationCode = selectedStation?['tbl_station_code'] ?? 'N/A';
-    // This logic now correctly uses the full classification object if available.
-    final classification = selectedClassification?['classification_name'] ?? classificationId?.toString() ?? 'N/A';
-
-    final buffer = StringBuffer()
-      ..writeln('✅ *Tarball Sample $submissionType Submitted:*')
-      ..writeln()
-      ..writeln('*Station Name & Code:* $stationName ($stationCode)')
-      ..writeln('*Date of Submission:* $samplingDate')
-      ..writeln('*Submitted by User:* $firstSampler')
-      ..writeln('*Classification:* $classification')
-      ..writeln('*Status of Submission:* Successful');
-
-    // Add distance alert if relevant
-    if (distanceDifference != null && distanceDifference! > 0) {
-      buffer
-        ..writeln()
-        ..writeln('🔔 *Alert:*')
-        ..writeln('*Distance from station:* ${(distanceDifference! * 1000).toStringAsFixed(0)} meters');
-
-      if (distanceDifferenceRemarks != null && distanceDifferenceRemarks!.isNotEmpty) {
-        buffer.writeln('*Remarks for distance:* $distanceDifferenceRemarks');
-      }
-    }
-
-    return buffer.toString();
-  }
+  // --- REMOVED: generateTelegramAlertMessage method ---
+  // Logic moved to MarineTarballSamplingService
 
   /// Converts the form's text and selection data into a Map suitable for JSON encoding.
   /// This map will be sent as the body of the first API request.
@@ -113,7 +102,7 @@ class TarballSamplingData {
       'current_latitude': currentLatitude ?? '',
       'current_longitude': currentLongitude ?? '',
       'distance_difference': distanceDifference?.toString() ?? '',
-      'distance_remarks': distanceDifferenceRemarks ?? '',
+      'distance_remarks': distanceDifferenceRemarks ?? '', // Corrected key based on service
       'optional_photo_remark_01': optionalRemark1 ?? '',
       'optional_photo_remark_02': optionalRemark2 ?? '',
       'optional_photo_remark_03': optionalRemark3 ?? '',
@@ -125,6 +114,8 @@ class TarballSamplingData {
       'first_sampler_name': firstSampler ?? '',
       'classification_name': selectedClassification?['classification_name']?.toString() ?? '',
     };
+    // Remove keys with empty string values before sending
+    data.removeWhere((key, value) => value.isEmpty);
     return data;
   }
 
@@ -143,8 +134,9 @@ class TarballSamplingData {
     };
   }
 
-  /// Creates a single JSON object with all submission data, mimicking 'db.json'
+  /// Creates a single JSON object with all submission data for offline storage.
   Map<String, dynamic> toDbJson() {
+    // Include image paths for local storage
     return {
       'firstSampler': firstSampler,
       'firstSamplerUserId': firstSamplerUserId,
@@ -162,9 +154,17 @@ class TarballSamplingData {
       'distanceDifferenceRemarks': distanceDifferenceRemarks,
       'classificationId': classificationId,
       'selectedClassification': selectedClassification,
+      'leftCoastalViewImage': leftCoastalViewImage?.path,
+      'rightCoastalViewImage': rightCoastalViewImage?.path,
+      'verticalLinesImage': verticalLinesImage?.path,
+      'horizontalLineImage': horizontalLineImage?.path,
+      'optionalImage1': optionalImage1?.path,
       'optionalRemark1': optionalRemark1,
+      'optionalImage2': optionalImage2?.path,
       'optionalRemark2': optionalRemark2,
+      'optionalImage3': optionalImage3?.path,
       'optionalRemark3': optionalRemark3,
+      'optionalImage4': optionalImage4?.path,
       'optionalRemark4': optionalRemark4,
       'reportId': reportId,
       'submissionStatus': submissionStatus,
@@ -174,24 +174,26 @@ class TarballSamplingData {
 
   /// Creates a JSON object for basic form info, mimicking 'basic_form.json'.
   Map<String, dynamic> toBasicFormJson() {
-    return {
+    final data = {
       'tech_name': firstSampler,
-      'sampler_2ndname': secondSampler?['user_name'],
+      'sampler_2ndname': secondSampler?['first_name'], // Assuming first_name is appropriate
       'sample_date': samplingDate,
       'sample_time': samplingTime,
       'sample_state': selectedStateName,
-      'station_id': selectedStation?['tbl_station_code'],
+      'station_id': selectedStation?['tbl_station_code'], // Use station code
       'station_latitude': stationLatitude,
       'station_longitude': stationLongitude,
-      'latitude': currentLatitude,
-      'longitude': currentLongitude,
-      'sample_id': reportId, // Using reportId as a unique identifier for the sample.
+      'latitude': currentLatitude, // Current location
+      'longitude': currentLongitude, // Current location
+      'sample_id': reportId, // Using reportId if available
     };
+    data.removeWhere((key, value) => value == null);
+    return data;
   }
 
   /// Creates a JSON object for sensor readings, mimicking 'reading.json'.
   Map<String, dynamic> toReadingJson() {
-    return {
+    final data = {
       'classification': selectedClassification?['classification_name'],
       'classification_id': classificationId,
       'optional_remark_1': optionalRemark1,
@@ -199,17 +201,21 @@ class TarballSamplingData {
       'optional_remark_3': optionalRemark3,
       'optional_remark_4': optionalRemark4,
       'distance_difference': distanceDifference,
-      'distance_difference_remarks': distanceDifferenceRemarks,
+      'distance_difference_remarks': distanceDifferenceRemarks, // Corrected key
     };
+    data.removeWhere((key, value) => value == null || (value is String && value.isEmpty));
+    return data;
   }
 
   /// Creates a JSON object for manual info, mimicking 'manual_info.json'.
   Map<String, dynamic> toManualInfoJson() {
-    return {
-      // Tarball forms don't have a specific 'weather' or general remarks field,
-      // so we use the distance remarks as a stand-in if available.
-      'remarks_event': distanceDifferenceRemarks,
-      'remarks_lab': null,
+    final data = {
+      // Tarball forms don't have weather or general remarks separate from distance
+      'weather': null, // Explicitly null if not collected
+      'remarks_event': distanceDifferenceRemarks, // Use distance remarks if relevant
+      'remarks_lab': null, // Explicitly null if not collected
     };
+    data.removeWhere((key, value) => value == null || (value is String && value.isEmpty));
+    return data;
   }
 }

lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_1_sampling_info.dart

@@ -1 +1,807 @@
 // lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_1_sampling_info.dart
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:dropdown_search/dropdown_search.dart';
+import 'package:intl/intl.dart';
+import 'package:simple_barcode_scanner/simple_barcode_scanner.dart';
+
+import '../../../../auth_provider.dart';
+import '../../../../models/marine_inves_manual_sampling_data.dart';
+import '../../../../services/marine_investigative_sampling_service.dart';
+
+class MarineInvesManualStep1SamplingInfo extends StatefulWidget {
+  final MarineInvesManualSamplingData data;
+  final VoidCallback onNext;
+
+  const MarineInvesManualStep1SamplingInfo({
+    super.key,
+    required this.data,
+    required this.onNext,
+  });
+
+  @override
+  State<MarineInvesManualStep1SamplingInfo> createState() => _MarineInvesManualStep1SamplingInfoState();
+}
+
+class _MarineInvesManualStep1SamplingInfoState extends State<MarineInvesManualStep1SamplingInfo> {
+  final _formKey = GlobalKey<FormState>();
+  bool _isLoadingLocation = false;
+
+  late final TextEditingController _firstSamplerController;
+  late final TextEditingController _dateController;
+  late final TextEditingController _timeController;
+  late final TextEditingController _barcodeController;
+  late final TextEditingController _stationLatController;
+  late final TextEditingController _stationLonController;
+  late final TextEditingController _currentLatController;
+  late final TextEditingController _currentLonController;
+
+  // --- NEW: Controllers for 'New Location' ---
+  late final TextEditingController _newStationNameController;
+  late final TextEditingController _newStationCodeController;
+
+  // --- NEW: State for Station Selection ---
+  String _stationType = 'Existing Manual Station';
+  final List<String> _stationTypeOptions = ['Existing Manual Station', 'Existing Tarball Station', 'New Location'];
+
+  // --- Lists for Dropdowns ---
+  List<String> _manualStatesList = [];
+  List<String> _categoriesForManualState = [];
+  List<Map<String, dynamic>> _stationsForManualCategory = [];
+
+  List<String> _tarballStatesList = [];
+  List<Map<String, dynamic>> _stationsForTarballState = [];
+
+  final List<String> _samplingTypes = ['Schedule', 'Ad-Hoc', 'Complaint', 'Investigative'];
+
+  @override
+  void initState() {
+    super.initState();
+    _initializeControllers();
+    _initializeForm();
+  }
+
+  @override
+  void dispose() {
+    _firstSamplerController.dispose();
+    _dateController.dispose();
+    _timeController.dispose();
+    _barcodeController.dispose();
+    _stationLatController.dispose();
+    _stationLonController.dispose();
+    _currentLatController.dispose();
+    _currentLonController.dispose();
+    _newStationNameController.dispose();
+    _newStationCodeController.dispose();
+    super.dispose();
+  }
+
+  void _initializeControllers() {
+    _firstSamplerController = TextEditingController();
+    _dateController = TextEditingController();
+    _timeController = TextEditingController();
+    _barcodeController = TextEditingController(text: widget.data.sampleIdCode);
+    _stationLatController = TextEditingController(text: widget.data.stationLatitude);
+    _stationLonController = TextEditingController(text: widget.data.stationLongitude);
+    _currentLatController = TextEditingController(text: widget.data.currentLatitude);
+    _currentLonController = TextEditingController(text: widget.data.currentLongitude);
+
+    _newStationNameController = TextEditingController(text: widget.data.newStationName);
+    _newStationCodeController = TextEditingController(text: widget.data.newStationCode);
+  }
+
+  void _initializeForm() {
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+
+    widget.data.firstSamplerName = auth.profileData?['first_name'] ?? 'Current User';
+    widget.data.firstSamplerUserId = auth.profileData?['user_id'];
+    _firstSamplerController.text = widget.data.firstSamplerName!;
+
+    _dateController.text = widget.data.samplingDate!;
+    _timeController.text = widget.data.samplingTime!;
+
+    if (widget.data.samplingType == null) {
+      widget.data.samplingType = 'Investigative';
+    }
+
+    _stationType = widget.data.stationTypeSelection ?? 'Existing Manual Station';
+
+    // --- Load Manual Station Data ---
+    final allManualStations = auth.manualStations ?? [];
+    if (allManualStations.isNotEmpty) {
+      _manualStatesList = allManualStations.map((s) => s['state_name'] as String?).whereType<String>().toSet().toList()..sort();
+      if (widget.data.selectedManualStateName != null) {
+        _categoriesForManualState = allManualStations
+            .where((s) => s['state_name'] == widget.data.selectedManualStateName)
+            .map((s) => s['category_name'] as String?)
+            .whereType<String>()
+            .toSet().toList()..sort();
+      }
+      if (widget.data.selectedManualCategoryName != null) {
+        _stationsForManualCategory = allManualStations
+            .where((s) => s['state_name'] == widget.data.selectedManualStateName && s['category_name'] == widget.data.selectedManualCategoryName)
+            .toList()..sort((a, b) => (a['man_station_code'] ?? '').compareTo(b['man_station_code'] ?? ''));
+      }
+    }
+
+    // --- Load Tarball Station Data ---
+    final allTarballStations = auth.tarballStations ?? [];
+    if (allTarballStations.isNotEmpty) {
+      _tarballStatesList = allTarballStations.map((s) => s['state_name'] as String?).whereType<String>().toSet().toList()..sort();
+      if (widget.data.selectedTarballStateName != null) {
+        _stationsForTarballState = allTarballStations
+            .where((s) => s['state_name'] == widget.data.selectedTarballStateName)
+            .toList()..sort((a, b) => (a['tbl_station_code'] ?? '').compareTo(b['tbl_station_code'] ?? ''));
+      }
+    }
+  }
+
+  /// --- NEW: Handle Station Type Change ---
+  void _handleStationTypeChange(String? value) {
+    if (value == null) return;
+    setState(() {
+      _stationType = value;
+      widget.data.stationTypeSelection = value;
+
+      // Clear all station-related data to avoid conflicts
+      widget.data.selectedManualStateName = null;
+      widget.data.selectedManualCategoryName = null;
+      widget.data.selectedStation = null;
+
+      widget.data.selectedTarballStateName = null;
+      widget.data.selectedTarballStation = null;
+
+      widget.data.newStationName = null;
+      widget.data.newStationCode = null;
+      _newStationNameController.clear();
+      _newStationCodeController.clear();
+
+      widget.data.stationLatitude = null;
+      widget.data.stationLongitude = null;
+      _stationLatController.clear();
+      _stationLonController.clear();
+
+      widget.data.distanceDifferenceInKm = null;
+    });
+  }
+
+  Future<void> _getCurrentLocation() async {
+    setState(() => _isLoadingLocation = true);
+    final service = Provider.of<MarineInvestigativeSamplingService>(context, listen: false);
+    try {
+      final position = await service.getCurrentLocation();
+      if (mounted) {
+        setState(() {
+          widget.data.currentLatitude = position.latitude.toString();
+          widget.data.currentLongitude = position.longitude.toString();
+          _currentLatController.text = widget.data.currentLatitude!;
+          _currentLonController.text = widget.data.currentLongitude!;
+
+          // If 'New Location' is selected, also populate the station lat/lon
+          if (_stationType == 'New Location') {
+            widget.data.stationLatitude = widget.data.currentLatitude;
+            widget.data.stationLongitude = widget.data.currentLongitude;
+            _stationLatController.text = widget.data.stationLatitude!;
+            _stationLonController.text = widget.data.stationLongitude!;
+          }
+          _calculateDistance();
+        });
+      }
+    } catch (e) {
+      if(mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Failed to get location: $e')));
+      }
+    } finally {
+      if (mounted) {
+        setState(() => _isLoadingLocation = false);
+      }
+    }
+  }
+
+  void _calculateDistance() {
+    final lat1Str = widget.data.stationLatitude;
+    final lon1Str = widget.data.stationLongitude;
+    final lat2Str = widget.data.currentLatitude;
+    final lon2Str = widget.data.currentLongitude;
+
+    if (lat1Str != null && lon1Str != null && lat2Str != null && lon2Str != null) {
+      final service = Provider.of<MarineInvestigativeSamplingService>(context, listen: false);
+      final lat1 = double.tryParse(lat1Str);
+      final lon1 = double.tryParse(lon1Str);
+      final lat2 = double.tryParse(lat2Str);
+      final lon2 = double.tryParse(lon2Str);
+
+      if (lat1 != null && lon1 != null && lat2 != null && lon2 != null) {
+        final distance = service.calculateDistance(lat1, lon1, lat2, lon2);
+        setState(() {
+          widget.data.distanceDifferenceInKm = distance;
+        });
+      } else {
+        setState(() {
+          widget.data.distanceDifferenceInKm = null; // Clear distance if coords invalid
+        });
+      }
+    } else {
+      setState(() {
+        widget.data.distanceDifferenceInKm = null; // Clear distance if coords missing
+      });
+    }
+  }
+
+  Future<void> _scanBarcode() async {
+    final result = await Navigator.push(
+      context,
+      MaterialPageRoute(builder: (context) => const SimpleBarcodeScannerPage()),
+    );
+    if (result is String && result != '-1' && mounted) {
+      setState(() {
+        widget.data.sampleIdCode = result;
+        _barcodeController.text = result;
+      });
+    }
+  }
+
+  // --- Re-used from original for manual stations ---
+  Future<void> _findAndShowNearbyStations() async {
+    if (widget.data.currentLatitude == null || widget.data.currentLatitude!.isEmpty) {
+      await _getCurrentLocation();
+      if (!mounted || widget.data.currentLatitude == null || widget.data.currentLatitude!.isEmpty) {
+        return;
+      }
+    }
+
+    final service = Provider.of<MarineInvestigativeSamplingService>(context, listen: false);
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+
+    final currentLat = double.parse(widget.data.currentLatitude!);
+    final currentLon = double.parse(widget.data.currentLongitude!);
+    final allStations = auth.manualStations ?? []; // Only search manual stations
+    final List<Map<String, dynamic>> nearbyStations = [];
+
+    for (var station in allStations) {
+      final stationLat = station['man_latitude'];
+      final stationLon = station['man_longitude'];
+
+      // Ensure coordinates are numbers before calculating distance
+      if (stationLat is num && stationLon is num) {
+        final distance = service.calculateDistance(currentLat, currentLon, stationLat.toDouble(), stationLon.toDouble());
+        if (distance <= 5.0) { // 5km radius
+          nearbyStations.add({'station': station, 'distance': distance});
+        }
+      } else {
+        debugPrint("Skipping station ${station['man_station_code']} due to invalid coordinates: Lat=$stationLat, Lon=$stationLon");
+      }
+    }
+
+    nearbyStations.sort((a, b) => a['distance'].compareTo(b['distance']));
+
+    if (!mounted) return;
+
+    final selectedStation = await showDialog<Map<String, dynamic>>(
+      context: context,
+      builder: (context) => _NearbyStationsDialog(nearbyStations: nearbyStations),
+    );
+
+    if (selectedStation != null) {
+      _updateFormWithSelectedStation(selectedStation);
+    }
+  }
+
+  // --- Re-used from original for manual stations ---
+  void _updateFormWithSelectedStation(Map<String, dynamic> station) {
+    final allStations = Provider.of<AuthProvider>(context, listen: false).manualStations ?? [];
+    setState(() {
+      // Update State
+      widget.data.selectedManualStateName = station['state_name'];
+
+      // Update Category List based on new State
+      final categories = allStations
+          .where((s) => s['state_name'] == widget.data.selectedManualStateName)
+          .map((s) => s['category_name'] as String?)
+          .whereType<String>()
+          .toSet()
+          .toList();
+      categories.sort();
+      _categoriesForManualState = categories;
+
+      // Update Category
+      widget.data.selectedManualCategoryName = station['category_name'];
+
+      // Update Station List based on new State and Category
+      _stationsForManualCategory = allStations
+          .where((s) =>
+      s['state_name'] == widget.data.selectedManualStateName &&
+          s['category_name'] == widget.data.selectedManualCategoryName)
+          .toList()
+        ..sort((a, b) => (a['man_station_code'] ?? '').compareTo(b['man_station_code'] ?? ''));
+
+      // Update Selected Station and its coordinates
+      widget.data.selectedStation = station;
+      widget.data.stationLatitude = station['man_latitude']?.toString();
+      widget.data.stationLongitude = station['man_longitude']?.toString();
+      _stationLatController.text = widget.data.stationLatitude ?? '';
+      _stationLonController.text = widget.data.stationLongitude ?? '';
+
+      // Recalculate distance
+      _calculateDistance();
+    });
+  }
+
+  void _goToNextStep() {
+    if (_formKey.currentState!.validate()) {
+      _formKey.currentState!.save();
+
+      // The distance check applies to all 3 types.
+      // For "New Location", it compares manually-entered Lat/Lon vs. Current Lat/Lon.
+      final distanceInMeters = (widget.data.distanceDifferenceInKm ?? 0) * 1000;
+
+      // Only show remark dialog if distance is > 50m AND station lat/lon are actually set
+      // (prevents dialog for 'New Location' before coords are entered/fetched)
+      if (distanceInMeters > 50 && widget.data.stationLatitude != null && widget.data.stationLongitude != null) {
+        _showDistanceRemarkDialog();
+      } else {
+        widget.data.distanceDifferenceRemarks = null; // Clear remarks if within limit
+        widget.onNext();
+      }
+    }
+  }
+
+  Future<void> _showDistanceRemarkDialog() async {
+    final remarkController = TextEditingController(text: widget.data.distanceDifferenceRemarks);
+    final dialogFormKey = GlobalKey<FormState>();
+
+    return showDialog<void>(
+      context: context,
+      barrierDismissible: false,
+      builder: (BuildContext context) {
+        return AlertDialog(
+          title: const Text('Distance Warning'),
+          content: SingleChildScrollView(
+            child: Form(
+              key: dialogFormKey,
+              child: Column(
+                mainAxisSize: MainAxisSize.min,
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  const Text('Your current location is more than 50m away from the selected/entered station location.'),
+                  const SizedBox(height: 16),
+                  TextFormField(
+                    controller: remarkController,
+                    decoration: const InputDecoration(
+                      labelText: 'Remarks *',
+                      hintText: 'Please provide a reason...',
+                      border: OutlineInputBorder(),
+                    ),
+                    validator: (value) {
+                      if (value == null || value.trim().isEmpty) {
+                        return 'Remarks are required to continue.';
+                      }
+                      return null;
+                    },
+                    maxLines: 3,
+                  ),
+                ],
+              ),
+            ),
+          ),
+          actions: <Widget>[
+            TextButton(
+              child: const Text('Cancel'),
+              onPressed: () {
+                Navigator.of(context).pop();
+              },
+            ),
+            FilledButton(
+              child: const Text('Confirm'),
+              onPressed: () {
+                if (dialogFormKey.currentState!.validate()) {
+                  setState(() {
+                    widget.data.distanceDifferenceRemarks = remarkController.text;
+                  });
+                  Navigator.of(context).pop();
+                  widget.onNext(); // Proceed after confirming remark
+                }
+              },
+            ),
+          ],
+        );
+      },
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+    final allUsers = auth.allUsers ?? [];
+    final secondSamplersList = allUsers.where((user) => user['user_id'] != auth.profileData?['user_id']).toList()
+      ..sort((a, b) => (a['first_name'] ?? '').compareTo(b['first_name'] ?? ''));
+
+    return Form(
+      key: _formKey,
+      child: ListView(
+        padding: const EdgeInsets.all(24.0),
+        children: [
+          Text("Sampling Information", style: Theme.of(context).textTheme.headlineSmall),
+          const SizedBox(height: 24),
+          TextFormField(controller: _firstSamplerController, readOnly: true, decoration: const InputDecoration(labelText: '1st Sampler')),
+          const SizedBox(height: 16),
+          DropdownSearch<Map<String, dynamic>>(
+            items: secondSamplersList,
+            selectedItem: widget.data.secondSampler,
+            itemAsString: (sampler) => "${sampler['first_name']} ${sampler['last_name']}",
+            onChanged: (sampler) => widget.data.secondSampler = sampler,
+            popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search Sampler..."))),
+            dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: '2nd Sampler (Optional)')),
+          ),
+          const SizedBox(height: 16),
+          Row(
+            children: [
+              Expanded(child: TextFormField(controller: _dateController, readOnly: true, decoration: const InputDecoration(labelText: 'Date'))),
+              const SizedBox(width: 16),
+              Expanded(child: TextFormField(controller: _timeController, readOnly: true, decoration: const InputDecoration(labelText: 'Time'))),
+            ],
+          ),
+          const SizedBox(height: 16),
+          DropdownButtonFormField<String>(
+            value: widget.data.samplingType,
+            items: _samplingTypes.map((type) => DropdownMenuItem(value: type, child: Text(type))).toList(),
+            onChanged: (value) => setState(() => widget.data.samplingType = value),
+            decoration: const InputDecoration(labelText: 'Sampling Type *'),
+            validator: (value) => value == null ? 'Please select a type' : null,
+          ),
+          const SizedBox(height: 24),
+
+          // --- NEW: Station Type Selection ---
+          Text("Station Selection", style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 16),
+          DropdownButtonFormField<String>(
+            value: _stationType,
+            items: _stationTypeOptions.map((type) => DropdownMenuItem(value: type, child: Text(type))).toList(),
+            onChanged: _handleStationTypeChange,
+            decoration: const InputDecoration(labelText: 'Station Source *'),
+            validator: (value) => value == null ? 'Please select a station source' : null, // Added validator
+          ),
+          const SizedBox(height: 16),
+
+          // --- NEW: Conditional Station Widgets ---
+          if (_stationType == 'Existing Manual Station')
+            _buildManualStationSelectors(auth.manualStations ?? []),
+
+          if (_stationType == 'Existing Tarball Station')
+            _buildTarballStationSelectors(auth.tarballStations ?? []),
+
+          if (_stationType == 'New Location')
+            _buildNewLocationFields(),
+
+          // --- Location Verification (Common to all) ---
+          const SizedBox(height: 24),
+          Text("Location Verification", style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 16),
+          TextFormField(controller: _currentLatController, readOnly: true, decoration: const InputDecoration(labelText: 'Current Latitude')),
+          const SizedBox(height: 16),
+          TextFormField(controller: _currentLonController, readOnly: true, decoration: const InputDecoration(labelText: 'Current Longitude')),
+          if (widget.data.distanceDifferenceInKm != null)
+            Padding(
+              padding: const EdgeInsets.only(top: 16.0),
+              child: Container(
+                padding: const EdgeInsets.all(12),
+                decoration: BoxDecoration(
+                  color: ((widget.data.distanceDifferenceInKm ?? 0) * 1000) > 50 ? Colors.red.withOpacity(0.1) : Colors.green.withOpacity(0.1),
+                  borderRadius: BorderRadius.circular(8),
+                  border: Border.all(color: ((widget.data.distanceDifferenceInKm ?? 0) * 1000) > 50 ? Colors.red : Colors.green),
+                ),
+                child: RichText(
+                  textAlign: TextAlign.center,
+                  text: TextSpan(
+                    style: Theme.of(context).textTheme.bodyLarge,
+                    children: <TextSpan>[
+                      const TextSpan(text: 'Distance from Station: '),
+                      TextSpan(
+                        text: '${(widget.data.distanceDifferenceInKm! * 1000).toStringAsFixed(0)} meters',
+                        style: TextStyle(
+                            fontWeight: FontWeight.bold,
+                            color: ((widget.data.distanceDifferenceInKm ?? 0) * 1000) > 50 ? Colors.red : Colors.green
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
+              ),
+            ),
+          const SizedBox(height: 16),
+          OutlinedButton.icon(
+            onPressed: _isLoadingLocation ? null : _getCurrentLocation,
+            icon: _isLoadingLocation ? const SizedBox(width: 20, height: 20, child: CircularProgressIndicator(strokeWidth: 2)) : const Icon(Icons.location_searching),
+            label: Text(_stationType == 'New Location' ? "Get & Use Current Location" : "Get Current Location"),
+            style: OutlinedButton.styleFrom(
+              padding: const EdgeInsets.symmetric(vertical: 12), // Consistent padding
+            ),
+          ),
+          const SizedBox(height: 16),
+
+          // --- Sample ID (Common to all) ---
+          TextFormField(
+            controller: _barcodeController,
+            decoration: InputDecoration(
+              labelText: 'Sample ID Code *',
+              suffixIcon: IconButton(
+                icon: const Icon(Icons.qr_code_scanner),
+                onPressed: _scanBarcode,
+              ),
+            ),
+            validator: (val) => val == null || val.isEmpty ? "Sample ID is required" : null,
+            onSaved: (val) => widget.data.sampleIdCode = val,
+            onChanged: (val) => widget.data.sampleIdCode = val, // Update data model on change
+          ),
+          const SizedBox(height: 32),
+          ElevatedButton(
+            onPressed: _goToNextStep,
+            style: ElevatedButton.styleFrom(padding: const EdgeInsets.symmetric(vertical: 16)),
+            child: const Text('Next'),
+          ),
+          const SizedBox(height: 16), // Add padding at the bottom
+        ],
+      ),
+    );
+  }
+
+  /// --- Widget builder for Manual Station selection ---
+  Widget _buildManualStationSelectors(List<Map<String, dynamic>> allStations) {
+    return Column(
+      children: [
+        DropdownSearch<String>(
+          items: _manualStatesList,
+          selectedItem: widget.data.selectedManualStateName,
+          popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search State..."))),
+          dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: "Select State *")),
+          onChanged: (state) {
+            setState(() {
+              widget.data.selectedManualStateName = state;
+              widget.data.selectedManualCategoryName = null;
+              widget.data.selectedStation = null;
+              _stationLatController.clear();
+              _stationLonController.clear();
+              widget.data.distanceDifferenceInKm = null;
+
+              // --- CORRECTED LOGIC ---
+              if (state != null) {
+                _categoriesForManualState = allStations
+                    .where((s) => s['state_name'] == state)
+                    .map((s) => s['category_name'] as String?)
+                    .whereType<String>()
+                    .toSet()
+                    .toList();
+                _categoriesForManualState.sort(); // Sort after creating the list
+              } else {
+                _categoriesForManualState = <String>[];
+              }
+              // --- END CORRECTION ---
+
+              _stationsForManualCategory = []; // Clear stations list
+            });
+          },
+          validator: (val) => val == null ? "State is required" : null,
+        ),
+        const SizedBox(height: 16),
+        DropdownSearch<String>(
+          items: _categoriesForManualState,
+          selectedItem: widget.data.selectedManualCategoryName,
+          enabled: widget.data.selectedManualStateName != null,
+          popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search Category..."))),
+          dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: "Select Category *")),
+          onChanged: (category) {
+            setState(() {
+              widget.data.selectedManualCategoryName = category;
+              widget.data.selectedStation = null;
+              _stationLatController.clear();
+              _stationLonController.clear();
+              widget.data.distanceDifferenceInKm = null;
+
+              // --- CORRECTED LOGIC (Similar structure) ---
+              if (category != null) {
+                _stationsForManualCategory = allStations
+                    .where((s) => s['state_name'] == widget.data.selectedManualStateName && s['category_name'] == category)
+                    .toList();
+                _stationsForManualCategory.sort((a, b) => (a['man_station_code'] ?? '').compareTo(b['man_station_code'] ?? '')); // Sort after creating
+              } else {
+                _stationsForManualCategory = [];
+              }
+              // --- END CORRECTION ---
+            });
+          },
+          validator: (val) => widget.data.selectedManualStateName != null && val == null ? "Category is required" : null,
+        ),
+        const SizedBox(height: 16),
+        DropdownSearch<Map<String, dynamic>>(
+          items: _stationsForManualCategory,
+          selectedItem: widget.data.selectedStation,
+          enabled: widget.data.selectedManualCategoryName != null,
+          itemAsString: (station) => "${station['man_station_code']} - ${station['man_station_name']}",
+          popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search Station..."))),
+          dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: "Select Station *")),
+          onChanged: (station) => setState(() {
+            widget.data.selectedStation = station;
+            widget.data.stationLatitude = station?['man_latitude']?.toString();
+            widget.data.stationLongitude = station?['man_longitude']?.toString();
+            _stationLatController.text = widget.data.stationLatitude ?? '';
+            _stationLonController.text = widget.data.stationLongitude ?? '';
+            _calculateDistance(); // Recalculate distance when station changes
+          }),
+          validator: (val) => widget.data.selectedManualCategoryName != null && val == null ? "Station is required" : null,
+        ),
+        const SizedBox(height: 16),
+        TextFormField(controller: _stationLatController, readOnly: true, decoration: const InputDecoration(labelText: 'Station Latitude')),
+        const SizedBox(height: 16),
+        TextFormField(controller: _stationLonController, readOnly: true, decoration: const InputDecoration(labelText: 'Station Longitude')),
+        const SizedBox(height: 16),
+        ElevatedButton.icon(
+          icon: const Icon(Icons.explore_outlined),
+          label: const Text("NEARBY STATION"),
+          onPressed: _isLoadingLocation ? null : _findAndShowNearbyStations,
+          style: ElevatedButton.styleFrom(padding: const EdgeInsets.symmetric(vertical: 12)),
+        ),
+      ],
+    );
+  }
+
+  /// --- Widget builder for Tarball Station selection ---
+  Widget _buildTarballStationSelectors(List<Map<String, dynamic>> allStations) {
+    return Column(
+      children: [
+        DropdownSearch<String>(
+          items: _tarballStatesList,
+          selectedItem: widget.data.selectedTarballStateName,
+          popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search State..."))),
+          dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: "Select State *")),
+          onChanged: (state) {
+            setState(() {
+              widget.data.selectedTarballStateName = state;
+              widget.data.selectedTarballStation = null;
+              _stationLatController.clear();
+              _stationLonController.clear();
+              widget.data.distanceDifferenceInKm = null;
+
+              // --- CORRECTED LOGIC ---
+              if (state != null) {
+                _stationsForTarballState = allStations
+                    .where((s) => s['state_name'] == state)
+                    .toList();
+                _stationsForTarballState.sort((a, b) => (a['tbl_station_code'] ?? '').compareTo(b['tbl_station_code'] ?? '')); // Sort after creating
+              } else {
+                _stationsForTarballState = <Map<String, dynamic>>[];
+              }
+              // --- END CORRECTION ---
+            });
+          },
+          validator: (val) => val == null ? "State is required" : null,
+        ),
+        const SizedBox(height: 16),
+        DropdownSearch<Map<String, dynamic>>(
+          items: _stationsForTarballState,
+          selectedItem: widget.data.selectedTarballStation,
+          enabled: widget.data.selectedTarballStateName != null,
+          itemAsString: (station) => "${station['tbl_station_code']} - ${station['tbl_station_name']}",
+          popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search Station..."))),
+          dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: "Select Station *")),
+          onChanged: (station) => setState(() {
+            widget.data.selectedTarballStation = station;
+            widget.data.stationLatitude = station?['tbl_latitude']?.toString();
+            widget.data.stationLongitude = station?['tbl_longitude']?.toString();
+            _stationLatController.text = widget.data.stationLatitude ?? '';
+            _stationLonController.text = widget.data.stationLongitude ?? '';
+            _calculateDistance(); // Recalculate distance when station changes
+          }),
+          validator: (val) => widget.data.selectedTarballStateName != null && val == null ? "Station is required" : null,
+        ),
+        const SizedBox(height: 16),
+        TextFormField(controller: _stationLatController, readOnly: true, decoration: const InputDecoration(labelText: 'Station Latitude')),
+        const SizedBox(height: 16),
+        TextFormField(controller: _stationLonController, readOnly: true, decoration: const InputDecoration(labelText: 'Station Longitude')),
+      ],
+    );
+  }
+
+  /// --- Widget builder for New Location fields ---
+  Widget _buildNewLocationFields() {
+    return Column(
+      children: [
+        TextFormField(
+          controller: _newStationNameController,
+          decoration: const InputDecoration(labelText: 'New Station Name *'),
+          validator: (val) => val == null || val.isEmpty ? "Station Name is required" : null,
+          onSaved: (val) => widget.data.newStationName = val,
+          onChanged: (val) => widget.data.newStationName = val, // Update data model on change
+        ),
+        const SizedBox(height: 16),
+        TextFormField(
+          controller: _newStationCodeController,
+          decoration: const InputDecoration(labelText: 'New Station Code *', hintText: "e.g., INV-001"),
+          validator: (val) => val == null || val.isEmpty ? "Station Code is required" : null,
+          onSaved: (val) => widget.data.newStationCode = val,
+          onChanged: (val) => widget.data.newStationCode = val, // Update data model on change
+        ),
+        const SizedBox(height: 16),
+        TextFormField(
+          controller: _stationLatController,
+          decoration: const InputDecoration(labelText: 'Station Latitude *', hintText: "Enter manually or use 'Get Location'"),
+          keyboardType: const TextInputType.numberWithOptions(decimal: true),
+          validator: (val) {
+            if (val == null || val.isEmpty) return "Latitude is required";
+            final lat = double.tryParse(val);
+            if (lat == null || lat < -90 || lat > 90) return "Enter a valid latitude (-90 to 90)";
+            return null;
+          },
+          onSaved: (val) => widget.data.stationLatitude = val,
+          onChanged: (val) {
+            widget.data.stationLatitude = val; // Update data model on change
+            _calculateDistance(); // Recalculate distance when manually changed
+          },
+        ),
+        const SizedBox(height: 16),
+        TextFormField(
+          controller: _stationLonController,
+          decoration: const InputDecoration(labelText: 'Station Longitude *', hintText: "Enter manually or use 'Get Location'"),
+          keyboardType: const TextInputType.numberWithOptions(decimal: true),
+          validator: (val) {
+            if (val == null || val.isEmpty) return "Longitude is required";
+            final lon = double.tryParse(val);
+            if (lon == null || lon < -180 || lon > 180) return "Enter a valid longitude (-180 to 180)";
+            return null;
+          },
+          onSaved: (val) => widget.data.stationLongitude = val,
+          onChanged: (val) {
+            widget.data.stationLongitude = val; // Update data model on change
+            _calculateDistance(); // Recalculate distance when manually changed
+          },
+        ),
+      ],
+    );
+  }
+}
+
+// --- Re-used Dialog Widget for Nearby Stations ---
+class _NearbyStationsDialog extends StatelessWidget {
+  final List<Map<String, dynamic>> nearbyStations;
+
+  const _NearbyStationsDialog({required this.nearbyStations});
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      title: const Text('Nearby Stations (within 5km)'),
+      content: SizedBox(
+        width: double.maxFinite,
+        child: nearbyStations.isEmpty
+            ? const Center(child: Text('No stations found within 5km of your current location.')) // More informative text
+            : ListView.builder(
+          shrinkWrap: true,
+          itemCount: nearbyStations.length,
+          itemBuilder: (context, index) {
+            final item = nearbyStations[index];
+            final station = item['station'] as Map<String, dynamic>;
+            final distanceInMeters = (item['distance'] as double) * 1000;
+
+            return Card(
+              margin: const EdgeInsets.symmetric(vertical: 4.0), // Add vertical margin
+              child: ListTile(
+                title: Text("${station['man_station_code'] ?? 'N/A'}"),
+                subtitle: Text("${station['man_station_name'] ?? 'N/A'}"),
+                trailing: Text("${distanceInMeters.toStringAsFixed(0)} m"),
+                onTap: () {
+                  Navigator.of(context).pop(station); // Return selected station
+                },
+              ),
+            );
+          },
+        ),
+      ),
+      actions: [
+        TextButton(
+          onPressed: () => Navigator.of(context).pop(), // Return null on cancel
+          child: const Text('Cancel'),
+        ),
+      ],
+    );
+  }
+}

lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_2_site_info.dart

@@ -1 +1,220 @@
 // lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_2_site_info.dart
+
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:image_picker/image_picker.dart';
+import 'package:provider/provider.dart';
+
+import '../../../../models/marine_inves_manual_sampling_data.dart';
+import '../../../../services/marine_investigative_sampling_service.dart';
+
+/// The second step of the Investigative Sampling form.
+/// Gathers on-site conditions (weather, tide) and handles all photo attachments.
+class MarineInvesManualStep2SiteInfo extends StatefulWidget {
+  final MarineInvesManualSamplingData data;
+  final VoidCallback onNext;
+
+  const MarineInvesManualStep2SiteInfo({
+    super.key,
+    required this.data,
+    required this.onNext,
+  });
+
+  @override
+  State<MarineInvesManualStep2SiteInfo> createState() => _MarineInvesManualStep2SiteInfoState();
+}
+
+class _MarineInvesManualStep2SiteInfoState extends State<MarineInvesManualStep2SiteInfo> {
+  final _formKey = GlobalKey<FormState>();
+  bool _isPickingImage = false;
+
+  late final TextEditingController _eventRemarksController;
+  late final TextEditingController _labRemarksController;
+
+  final List<String> _weatherOptions = ['Clear', 'Cloudy', 'Drizzle', 'Rainy', 'Windy'];
+  final List<String> _tideOptions = ['High', 'Low', 'Mid'];
+  final List<String> _seaConditionOptions = ['Calm', 'Moderate Wave', 'High Wave'];
+
+  @override
+  void initState() {
+    super.initState();
+    _eventRemarksController = TextEditingController(text: widget.data.eventRemarks);
+    _labRemarksController = TextEditingController(text: widget.data.labRemarks);
+  }
+
+  @override
+  void dispose() {
+    _eventRemarksController.dispose();
+    _labRemarksController.dispose();
+    super.dispose();
+  }
+
+  /// Handles picking and processing an image using the dedicated service.
+  void _setImage(Function(File?) setImageCallback, ImageSource source, String imageInfo, {required bool isRequired}) async {
+    if (_isPickingImage) return;
+    setState(() => _isPickingImage = true);
+
+    final service = Provider.of<MarineInvestigativeSamplingService>(context, listen: false);
+
+    // The service's pickAndProcessImage method will handle file naming
+    final file = await service.pickAndProcessImage(source, data: widget.data, imageInfo: imageInfo, isRequired: isRequired);
+
+    if (file != null) {
+      setState(() => setImageCallback(file));
+    } else if (mounted) {
+      _showSnackBar('Image selection failed. Please ensure all photos are taken in landscape mode.', isError: true);
+    }
+
+    if (mounted) {
+      setState(() => _isPickingImage = false);
+    }
+  }
+
+  /// Validates the form and all required images before proceeding.
+  void _goToNextStep() {
+    if (widget.data.leftLandViewImage == null ||
+        widget.data.rightLandViewImage == null ||
+        widget.data.waterFillingImage == null ||
+        widget.data.seawaterColorImage == null) {
+      _showSnackBar('Please attach all 4 required photos before proceeding.', isError: true);
+      return;
+    }
+
+    // Form validation handles the conditional requirement for Event Remarks
+    if (!_formKey.currentState!.validate()) {
+      return;
+    }
+
+    _formKey.currentState!.save();
+    widget.onNext();
+  }
+
+  void _showSnackBar(String message, {bool isError = false}) {
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+        content: Text(message),
+        backgroundColor: isError ? Colors.red : null,
+      ));
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    // Logic to determine if Event Remarks are required
+    final bool areAdditionalPhotosAttached = widget.data.phPaperImage != null ||
+        widget.data.optionalImage1 != null ||
+        widget.data.optionalImage2 != null ||
+        widget.data.optionalImage3 != null ||
+        widget.data.optionalImage4 != null;
+
+    return Form(
+      key: _formKey,
+      child: ListView(
+        padding: const EdgeInsets.all(24.0),
+        children: [
+          // --- Section: On-Site Information ---
+          Text("On-Site Information", style: Theme.of(context).textTheme.headlineSmall),
+          const SizedBox(height: 24),
+          DropdownButtonFormField<String>(
+            value: widget.data.weather,
+            items: _weatherOptions.map((item) => DropdownMenuItem(value: item, child: Text(item))).toList(),
+            onChanged: (value) => setState(() => widget.data.weather = value),
+            decoration: const InputDecoration(labelText: 'Weather *'),
+            validator: (value) => value == null ? 'Weather is required' : null,
+          ),
+          const SizedBox(height: 16),
+          DropdownButtonFormField<String>(
+            value: widget.data.tideLevel,
+            items: _tideOptions.map((item) => DropdownMenuItem(value: item, child: Text(item))).toList(),
+            onChanged: (value) => setState(() => widget.data.tideLevel = value),
+            decoration: const InputDecoration(labelText: 'Tide Level *'),
+            validator: (value) => value == null ? 'Tide level is required' : null,
+          ),
+          const SizedBox(height: 16),
+          DropdownButtonFormField<String>(
+            value: widget.data.seaCondition,
+            items: _seaConditionOptions.map((item) => DropdownMenuItem(value: item, child: Text(item))).toList(),
+            onChanged: (value) => setState(() => widget.data.seaCondition = value),
+            decoration: const InputDecoration(labelText: 'Sea Condition *'),
+            validator: (value) => value == null ? 'Sea condition is required' : null,
+          ),
+          const SizedBox(height: 24),
+
+          // --- Section: Required Photos ---
+          Text("Required Photos *", style: Theme.of(context).textTheme.titleLarge),
+          const Text("All photos must be taken in landscape (horizontal) orientation.", style: TextStyle(color: Colors.grey)),
+          const SizedBox(height: 8),
+          _buildImagePicker('Left Side Land View', 'LEFT_LAND_VIEW', widget.data.leftLandViewImage, (file) => widget.data.leftLandViewImage = file, isRequired: true),
+          _buildImagePicker('Right Side Land View', 'RIGHT_LAND_VIEW', widget.data.rightLandViewImage, (file) => widget.data.rightLandViewImage = file, isRequired: true),
+          _buildImagePicker('Filling Water into Sample Bottle', 'WATER_FILLING', widget.data.waterFillingImage, (file) => widget.data.waterFillingImage = file, isRequired: true),
+          _buildImagePicker('Seawater in Clear Glass Bottle', 'SEAWATER_COLOR', widget.data.seawaterColorImage, (file) => widget.data.seawaterColorImage = file, isRequired: true),
+          const SizedBox(height: 24),
+
+          // --- Section: Additional photos and conditional remarks ---
+          Text("Additional Photos & Remarks", style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 8),
+          _buildImagePicker('Examine Preservative (pH paper)', 'PH_PAPER', widget.data.phPaperImage, (file) => widget.data.phPaperImage = file, isRequired: false),
+          _buildImagePicker('Optional Photo 1', 'OPTIONAL_1', widget.data.optionalImage1, (file) => widget.data.optionalImage1 = file, isRequired: false),
+          _buildImagePicker('Optional Photo 2', 'OPTIONAL_2', widget.data.optionalImage2, (file) => widget.data.optionalImage2 = file, isRequired: false),
+          _buildImagePicker('Optional Photo 3', 'OPTIONAL_3', widget.data.optionalImage3, (file) => widget.data.optionalImage3 = file, isRequired: false),
+          _buildImagePicker('Optional Photo 4', 'OPTIONAL_4', widget.data.optionalImage4, (file) => widget.data.optionalImage4 = file, isRequired: false),
+          const SizedBox(height: 24),
+
+          Text("Remarks", style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 16),
+          // Event Remarks field is conditionally required
+          TextFormField(
+            controller: _eventRemarksController,
+            decoration: InputDecoration(
+                labelText: areAdditionalPhotosAttached ? 'Event Remarks *' : 'Event Remarks (Optional)',
+                hintText: 'e.g., unusual smells, colors, etc.'
+            ),
+            onSaved: (value) => widget.data.eventRemarks = value,
+            validator: (value) {
+              if (areAdditionalPhotosAttached && (value == null || value.trim().isEmpty)) {
+                return 'Event Remarks are required when attaching additional photos.';
+              }
+              return null;
+            },
+            maxLines: 3,
+          ),
+          const SizedBox(height: 16),
+          TextFormField(
+            controller: _labRemarksController,
+            decoration: const InputDecoration(labelText: 'Lab Remarks (Optional)'),
+            onSaved: (value) => widget.data.labRemarks = value,
+            maxLines: 3,
+          ),
+          const SizedBox(height: 32),
+          ElevatedButton(
+            onPressed: _goToNextStep,
+            style: ElevatedButton.styleFrom(padding: const EdgeInsets.symmetric(vertical: 16)),
+            child: const Text('Next'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  /// A reusable widget for picking and displaying an image
+  Widget _buildImagePicker(String title, String imageInfo, File? imageFile, Function(File?) setImageCallback, {bool isRequired = false}) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 8.0),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(title + (isRequired ? ' *' : ''), style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w500)),
+          const SizedBox(height: 8),
+          if (imageFile != null)
+            Stack(
+              // ... (Image preview stack - same as original)
+            )
+          else
+            Row(
+              // ... (Camera/Gallery buttons - same as original)
+            ),
+        ],
+      ),
+    );
+  }
+}

lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_3_data_capture.dart

@@ -1 +1,832 @@
 // lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_3_data_capture.dart
+
+import 'dart:async';
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:flutter_bluetooth_serial/flutter_bluetooth_serial.dart';
+import 'package:usb_serial/usb_serial.dart';
+
+import '../../../../auth_provider.dart';
+import '../../../../models/marine_inves_manual_sampling_data.dart';
+import '../../../../services/marine_investigative_sampling_service.dart';
+import '../../../../bluetooth/bluetooth_manager.dart'; // For connection state enum
+import '../../../../serial/serial_manager.dart';     // For connection state enum
+import '../../../../bluetooth/widgets/bluetooth_device_list_dialog.dart';
+import '../../../../serial/widget/serial_port_list_dialog.dart';
+
+class MarineInvesManualStep3DataCapture extends StatefulWidget {
+  final MarineInvesManualSamplingData data;
+  final VoidCallback onNext;
+
+  const MarineInvesManualStep3DataCapture({
+    super.key,
+    required this.data,
+    required this.onNext,
+  });
+
+  @override
+  State<MarineInvesManualStep3DataCapture> createState() => _MarineInvesManualStep3DataCaptureState();
+}
+
+class _MarineInvesManualStep3DataCaptureState extends State<MarineInvesManualStep3DataCapture> with WidgetsBindingObserver {
+  final _formKey = GlobalKey<FormState>();
+  bool _isLoading = false;
+  bool _isAutoReading = false;
+  StreamSubscription? _dataSubscription;
+
+  Timer? _lockoutTimer;
+  int _lockoutSecondsRemaining = 30;
+  bool _isLockedOut = false;
+
+  late final MarineInvestigativeSamplingService _samplingService;
+
+  Map<String, double>? _previousReadingsForComparison;
+  Set<String> _outOfBoundsKeys = {};
+
+  final Map<String, String> _parameterKeyToLimitName = const {
+    'oxygenConcentration': 'Oxygen Conc',
+    'oxygenSaturation': 'Oxygen Sat',
+    'ph': 'pH',
+    'salinity': 'Salinity',
+    'electricalConductivity': 'Conductivity',
+    'temperature': 'Temperature',
+    'tds': 'TDS',
+    'turbidity': 'Turbidity',
+    'tss': 'TSS',
+    'batteryVoltage': 'Battery',
+  };
+
+  final List<Map<String, dynamic>> _parameters = [];
+
+  final _sondeIdController = TextEditingController();
+  final _dateController = TextEditingController();
+  final _timeController = TextEditingController();
+  final _oxyConcController = TextEditingController();
+  final _oxySatController = TextEditingController();
+  final _phController = TextEditingController();
+  final _salinityController = TextEditingController();
+  final _ecController = TextEditingController();
+  final _tempController = TextEditingController();
+  final _tdsController = TextEditingController();
+  final _turbidityController = TextEditingController();
+  final _tssController = TextEditingController();
+  final _batteryController = TextEditingController();
+
+  @override
+  void initState() {
+    super.initState();
+    _samplingService = Provider.of<MarineInvestigativeSamplingService>(context, listen: false);
+    _initializeControllers();
+    WidgetsBinding.instance.addObserver(this);
+  }
+
+  @override
+  void dispose() {
+    _dataSubscription?.cancel();
+    _lockoutTimer?.cancel();
+    if (_samplingService.bluetoothConnectionState.value != BluetoothConnectionState.disconnected) {
+      _samplingService.disconnectFromBluetooth();
+    }
+    if (_samplingService.serialConnectionState.value != SerialConnectionState.disconnected) {
+      _samplingService.disconnectFromSerial();
+    }
+    _disposeControllers();
+    WidgetsBinding.instance.removeObserver(this);
+    super.dispose();
+  }
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    if (state == AppLifecycleState.resumed) {
+      if (mounted) setState(() {});
+    }
+  }
+
+  void _initializeControllers() {
+    widget.data.dataCaptureDate = widget.data.samplingDate;
+    widget.data.dataCaptureTime = widget.data.samplingTime;
+
+    _sondeIdController.text = widget.data.sondeId ?? '';
+    _dateController.text = widget.data.dataCaptureDate ?? '';
+    _timeController.text = widget.data.dataCaptureTime ?? '';
+
+    widget.data.oxygenConcentration ??= -999.0;
+    widget.data.oxygenSaturation ??= -999.0;
+    widget.data.ph ??= -999.0;
+    widget.data.salinity ??= -999.0;
+    widget.data.electricalConductivity ??= -999.0;
+    widget.data.temperature ??= -999.0;
+    widget.data.tds ??= -999.0;
+    widget.data.turbidity ??= -999.0;
+    widget.data.tss ??= -999.0;
+    widget.data.batteryVoltage ??= -999.0;
+
+    _oxyConcController.text = widget.data.oxygenConcentration!.toString();
+    _oxySatController.text = widget.data.oxygenSaturation!.toString();
+    _phController.text = widget.data.ph!.toString();
+    _salinityController.text = widget.data.salinity!.toString();
+    _ecController.text = widget.data.electricalConductivity!.toString();
+    _tempController.text = widget.data.temperature!.toString();
+    _tdsController.text = widget.data.tds!.toString();
+    _turbidityController.text = widget.data.turbidity!.toString();
+    _tssController.text = widget.data.tss!.toString();
+    _batteryController.text = widget.data.batteryVoltage!.toString();
+
+    if (_parameters.isEmpty) {
+      _parameters.addAll([
+        {'key': 'oxygenConcentration', 'icon': Icons.air, 'label': 'Oxygen Conc.', 'unit': 'mg/L', 'controller': _oxyConcController},
+        {'key': 'oxygenSaturation', 'icon': Icons.percent, 'label': 'Oxygen Sat.', 'unit': '%', 'controller': _oxySatController},
+        {'key': 'ph', 'icon': Icons.science_outlined, 'label': 'pH', 'unit': '', 'controller': _phController},
+        {'key': 'salinity', 'icon': Icons.waves, 'label': 'Salinity', 'unit': 'ppt', 'controller': _salinityController},
+        {'key': 'electricalConductivity', 'icon': Icons.flash_on, 'label': 'Conductivity', 'unit': 'µS/cm', 'controller': _ecController},
+        {'key': 'temperature', 'icon': Icons.thermostat, 'label': 'Temperature', 'unit': '°C', 'controller': _tempController},
+        {'key': 'tds', 'icon': Icons.grain, 'label': 'TDS', 'unit': 'mg/L', 'controller': _tdsController},
+        {'key': 'turbidity', 'icon': Icons.opacity, 'label': 'Turbidity', 'unit': 'NTU', 'controller': _turbidityController},
+        {'key': 'tss', 'icon': Icons.filter_alt_outlined, 'label': 'TSS', 'unit': 'mg/L', 'controller': _tssController},
+        {'key': 'batteryVoltage', 'icon': Icons.battery_charging_full, 'label': 'Battery', 'unit': 'V', 'controller': _batteryController},
+      ]);
+    }
+  }
+
+  void _disposeControllers() {
+    _sondeIdController.dispose();
+    _dateController.dispose();
+    _timeController.dispose();
+    _oxyConcController.dispose();
+    _oxySatController.dispose();
+    _phController.dispose();
+    _salinityController.dispose();
+    _ecController.dispose();
+    _tempController.dispose();
+    _tdsController.dispose();
+    _turbidityController.dispose();
+    _tssController.dispose();
+    _batteryController.dispose();
+  }
+
+  Future<void> _handleConnectionAttempt(String type) async {
+    final service = context.read<MarineInvestigativeSamplingService>();
+    final hasPermissions = await service.requestDevicePermissions();
+    if (!hasPermissions && mounted) {
+      _showSnackBar("Bluetooth & Location permissions are required to connect.", isError: true);
+      return;
+    }
+    _disconnectFromAll();
+    await Future.delayed(const Duration(milliseconds: 250));
+    final bool connectionSuccess = await _connectToDevice(type);
+    if (connectionSuccess && mounted) {
+      _dataSubscription?.cancel();
+      final stream = type == 'bluetooth' ? service.bluetoothDataStream : service.serialDataStream;
+      _dataSubscription = stream.listen((readings) {
+        if (mounted) _updateTextFields(readings);
+      });
+    }
+  }
+
+  Future<bool> _connectToDevice(String type) async {
+    setState(() => _isLoading = true);
+    final service = context.read<MarineInvestigativeSamplingService>();
+    bool success = false;
+    try {
+      if (type == 'bluetooth') {
+        final devices = await service.getPairedBluetoothDevices();
+        if (devices.isEmpty && mounted) {
+          _showSnackBar('No paired Bluetooth devices found.', isError: true);
+          return false;
+        }
+        final selectedDevice = await showBluetoothDeviceListDialog(context: context, devices: devices);
+        if (selectedDevice != null) {
+          await service.connectToBluetoothDevice(selectedDevice);
+          success = true;
+        }
+      } else if (type == 'serial') {
+        final devices = await service.getAvailableSerialDevices();
+        if (devices.isEmpty && mounted) {
+          _showSnackBar('No USB Serial devices found.', isError: true);
+          return false;
+        }
+        final selectedDevice = await showSerialPortListDialog(context: context, devices: devices);
+        if (selectedDevice != null) {
+          await service.connectToSerialDevice(selectedDevice);
+          success = true;
+        }
+      }
+    } catch (e) {
+      debugPrint("Connection failed: $e");
+      if (mounted) _showConnectionFailedDialog();
+    } finally {
+      if (mounted) setState(() => _isLoading = false);
+    }
+    return success;
+  }
+
+  Future<void> _showConnectionFailedDialog() async {
+    if (!mounted) return;
+    return showDialog<void>(
+      context: context,
+      barrierDismissible: false,
+      builder: (BuildContext context) {
+        return AlertDialog(
+          title: const Text('Connection Failed'),
+          content: const SingleChildScrollView(
+            child: Text('Could not connect to the device. Please check that the device is turned on, within range, and not connected to another application.'),
+          ),
+          actions: <Widget>[
+            TextButton(
+              child: const Text('OK'),
+              onPressed: () {
+                Navigator.of(context).pop();
+              },
+            ),
+          ],
+        );
+      },
+    );
+  }
+
+  void _startLockoutTimer() {
+    _lockoutTimer?.cancel();
+    setState(() {
+      _isLockedOut = true;
+      _lockoutSecondsRemaining = 30;
+    });
+
+    _lockoutTimer = Timer.periodic(const Duration(seconds: 1), (timer) {
+      if (_lockoutSecondsRemaining > 0) {
+        if (mounted) {
+          setState(() {
+            _lockoutSecondsRemaining--;
+          });
+        }
+      } else {
+        timer.cancel();
+        if (mounted) {
+          setState(() {
+            _isLockedOut = false;
+          });
+        }
+      }
+    });
+  }
+
+  void _toggleAutoReading(String activeType) {
+    final service = context.read<MarineInvestigativeSamplingService>();
+    setState(() {
+      _isAutoReading = !_isAutoReading;
+      if (_isAutoReading) {
+        if (activeType == 'bluetooth') service.startBluetoothAutoReading(); else service.startSerialAutoReading();
+        _startLockoutTimer();
+      } else {
+        if (activeType == 'bluetooth') service.stopBluetoothAutoReading(); else service.stopSerialAutoReading();
+      }
+    });
+  }
+
+  void _disconnect(String type) {
+    final service = context.read<MarineInvestigativeSamplingService>();
+    if (type == 'bluetooth') {
+      service.disconnectFromBluetooth();
+    } else {
+      service.disconnectFromSerial();
+    }
+    _dataSubscription?.cancel();
+    _dataSubscription = null;
+    _lockoutTimer?.cancel();
+    if (mounted) {
+      setState(() {
+        _isAutoReading = false;
+        _isLockedOut = false;
+      });
+    }
+  }
+
+  void _disconnectFromAll() {
+    final service = context.read<MarineInvestigativeSamplingService>();
+    if (service.bluetoothConnectionState.value != BluetoothConnectionState.disconnected) {
+      _disconnect('bluetooth');
+    }
+    if (service.serialConnectionState.value != SerialConnectionState.disconnected) {
+      _disconnect('serial');
+    }
+  }
+
+  void _updateTextFields(Map<String, double> readings) {
+    const defaultValue = -999.0;
+    setState(() {
+      _oxyConcController.text = (readings['Optical Dissolved Oxygen: Compensated mg/L'] ?? defaultValue).toStringAsFixed(5);
+      _oxySatController.text = (readings['Optical Dissolved Oxygen: Compensated % Saturation'] ?? defaultValue).toStringAsFixed(5);
+      _phController.text = (readings['PH: PH units'] ?? defaultValue).toStringAsFixed(5);
+      _tempController.text = (readings['External Temp: Degrees Celcius'] ?? defaultValue).toStringAsFixed(5);
+      _ecController.text = (readings['Conductivity: us/cm'] ?? defaultValue).toStringAsFixed(5);
+      _salinityController.text = (readings['Conductivity: Salinity'] ?? defaultValue).toStringAsFixed(5);
+      _tdsController.text = (readings['Conductivity:TDS mg/L'] ?? defaultValue).toStringAsFixed(5);
+      _tssController.text = (readings['Turbidity: TSS'] ?? defaultValue).toStringAsFixed(5);
+      _turbidityController.text = (readings['Turbidity: FNU'] ?? defaultValue).toStringAsFixed(5);
+      _batteryController.text = (readings['Sonde: Battery Voltage'] ?? defaultValue).toStringAsFixed(5);
+    });
+  }
+
+  void _validateAndProceed() {
+    if (_isLockedOut) {
+      _showSnackBar("Please wait for the initial reading period to complete.", isError: true);
+      return;
+    }
+
+    if (_isAutoReading) {
+      _showStopReadingDialog();
+      return;
+    }
+    if (!_formKey.currentState!.validate()) {
+      return;
+    }
+    _formKey.currentState!.save();
+
+    final currentReadings = _captureReadingsToMap();
+    final authProvider = Provider.of<AuthProvider>(context, listen: false);
+    final marineLimits = authProvider.marineParameterLimits ?? [];
+    final outOfBoundsParams = _validateParameters(currentReadings, marineLimits);
+
+    setState(() {
+      _outOfBoundsKeys = outOfBoundsParams.map((p) => _parameters.firstWhere((param) => param['label'] == p['label'])['key'] as String).toSet();
+    });
+
+    if (outOfBoundsParams.isNotEmpty) {
+      _showParameterLimitDialog(outOfBoundsParams, currentReadings);
+    } else {
+      _saveDataAndMoveOn(currentReadings);
+    }
+  }
+
+  Map<String, double> _captureReadingsToMap() {
+    final Map<String, double> readings = {};
+    for (var param in _parameters) {
+      final key = param['key'] as String;
+      final controller = param['controller'] as TextEditingController;
+      readings[key] = double.tryParse(controller.text) ?? -999.0;
+    }
+    return readings;
+  }
+
+  List<Map<String, dynamic>> _validateParameters(Map<String, double> readings, List<Map<String, dynamic>> limits) {
+    final List<Map<String, dynamic>> invalidParams = [];
+
+    // --- MODIFIED: Get station ID based on station type ---
+    int? stationId;
+    if (widget.data.stationTypeSelection == 'Existing Manual Station') {
+      stationId = widget.data.selectedStation?['station_id'];
+    }
+    // Note: Add logic here if Tarball or New Locations have different limits
+    // For now, we only validate against manual station limits
+
+    debugPrint("--- Parameter Validation Start (Investigative) ---");
+    debugPrint("Selected Station ID: $stationId");
+
+    double? _parseLimitValue(dynamic value) {
+      if (value == null) return null;
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    readings.forEach((key, value) {
+      if (value == -999.0) return;
+
+      final limitName = _parameterKeyToLimitName[key];
+      if (limitName == null) return;
+
+      debugPrint("Checking parameter: '$limitName' (key: '$key')");
+
+      Map<String, dynamic> limitData = {};
+
+      if (stationId != null) {
+        limitData = limits.firstWhere(
+              (l) => l['param_parameter_list'] == limitName && l['station_id']?.toString() == stationId.toString(),
+          orElse: () => {},
+        );
+      }
+
+      if (limitData.isNotEmpty) {
+        debugPrint("  > Found station-specific limit for Station ID $stationId: $limitData");
+      } else {
+        debugPrint("  > No station-specific limit found for Station ID $stationId. Skipping check for this parameter.");
+      }
+
+      if (limitData.isNotEmpty) {
+        final lowerLimit = _parseLimitValue(limitData['param_lower_limit']);
+        final upperLimit = _parseLimitValue(limitData['param_upper_limit']);
+
+        if ((lowerLimit != null && value < lowerLimit) || (upperLimit != null && value > upperLimit)) {
+          final paramInfo = _parameters.firstWhere((p) => p['key'] == key, orElse: () => {});
+          invalidParams.add({
+            'label': paramInfo['label'] ?? key,
+            'value': value,
+            'lower_limit': lowerLimit,
+            'upper_limit': upperLimit,
+          });
+        }
+      }
+    });
+
+    debugPrint("--- Parameter Validation End ---");
+
+    return invalidParams;
+  }
+
+  void _saveDataAndMoveOn(Map<String, double> readings) {
+    try {
+      const defaultValue = -999.0;
+      widget.data.temperature = readings['temperature'] ?? defaultValue;
+      widget.data.ph = readings['ph'] ?? defaultValue;
+      widget.data.salinity = readings['salinity'] ?? defaultValue;
+      widget.data.electricalConductivity = readings['electricalConductivity'] ?? defaultValue;
+      widget.data.oxygenConcentration = readings['oxygenConcentration'] ?? defaultValue;
+      widget.data.oxygenSaturation = readings['oxygenSaturation'] ?? defaultValue;
+      widget.data.tds = readings['tds'] ?? defaultValue;
+      widget.data.turbidity = readings['turbidity'] ?? defaultValue;
+      widget.data.tss = readings['tss'] ?? defaultValue;
+      widget.data.batteryVoltage = readings['batteryVoltage'] ?? defaultValue;
+    } catch (e) {
+      _showSnackBar("Could not save parameters due to a data format error.", isError: true);
+      return;
+    }
+
+    setState(() {
+      _outOfBoundsKeys.clear();
+      if (_previousReadingsForComparison != null) {
+        _previousReadingsForComparison = null;
+      }
+    });
+
+    widget.onNext();
+  }
+
+  void _showStopReadingDialog() {
+    showDialog(
+      context: context,
+      builder: (BuildContext context) {
+        return AlertDialog(
+          title: const Text('Data Collection Active'),
+          content: const Text('Please stop the live data collection before proceeding.'),
+          actions: <Widget>[
+            TextButton(
+              child: const Text('OK'),
+              onPressed: () => Navigator.of(context).pop(),
+            ),
+          ],
+        );
+      },
+    );
+  }
+
+  void _showSnackBar(String message, {bool isError = false}) {
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+        content: Text(message),
+        backgroundColor: isError ? Colors.red : null,
+      ));
+    }
+  }
+
+  Map<String, dynamic>? _getActiveConnectionDetails() {
+    final service = context.watch<MarineInvestigativeSamplingService>();
+    if (service.bluetoothConnectionState.value != BluetoothConnectionState.disconnected) {
+      return {'type': 'bluetooth', 'state': service.bluetoothConnectionState.value, 'name': service.connectedBluetoothDeviceName};
+    }
+    if (service.serialConnectionState.value != SerialConnectionState.disconnected) {
+      return {'type': 'serial', 'state': service.serialConnectionState.value, 'name': service.connectedSerialDeviceName};
+    }
+    return null;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final service = context.watch<MarineInvestigativeSamplingService>();
+    final activeConnection = _getActiveConnectionDetails();
+    final String? activeType = activeConnection?['type'] as String?;
+
+    return WillPopScope(
+      onWillPop: () async {
+        if (_isLockedOut) {
+          _showSnackBar("Please wait for the initial reading period to complete.", isError: true);
+          return false; // Prevent back navigation
+        }
+        return true; // Allow back navigation
+      },
+      child: Form(
+        key: _formKey,
+        child: ListView(
+          padding: const EdgeInsets.all(24.0),
+          children: [
+            Text("Data Capture", style: Theme.of(context).textTheme.headlineSmall),
+            const SizedBox(height: 16),
+            Row(
+              children: [
+                Expanded(
+                  child: activeType == 'bluetooth'
+                      ? FilledButton.icon(icon: const Icon(Icons.bluetooth_connected), label: const Text("Bluetooth"), onPressed: _isLoading ? null : () => _handleConnectionAttempt('bluetooth'))
+                      : OutlinedButton.icon(icon: const Icon(Icons.bluetooth), label: const Text("Bluetooth"), onPressed: _isLoading ? null : () => _handleConnectionAttempt('bluetooth')),
+                ),
+                const SizedBox(width: 16),
+                Expanded(
+                  child: activeType == 'serial'
+                      ? FilledButton.icon(icon: const Icon(Icons.usb), label: const Text("USB Serial"), onPressed: _isLoading ? null : () => _handleConnectionAttempt('serial'))
+                      : OutlinedButton.icon(icon: const Icon(Icons.usb), label: const Text("USB Serial"), onPressed: _isLoading ? null : () => _handleConnectionAttempt('serial')),
+                ),
+              ],
+            ),
+            const SizedBox(height: 16),
+            if (activeConnection != null)
+              _buildConnectionCard(type: activeConnection['type'], connectionState: activeConnection['state'], deviceName: activeConnection['name']),
+            const SizedBox(height: 24),
+            ValueListenableBuilder<String?>(
+              valueListenable: service.sondeId,
+              builder: (context, sondeId, child) {
+                final newSondeId = sondeId ?? '';
+                WidgetsBinding.instance.addPostFrameCallback((_) {
+                  if (mounted && _sondeIdController.text != newSondeId) {
+                    _sondeIdController.text = newSondeId;
+                    widget.data.sondeId = newSondeId;
+                  }
+                });
+                return TextFormField(
+                  controller: _sondeIdController,
+                  decoration: const InputDecoration(labelText: 'Sonde ID *', hintText: 'Connect device or enter manually'),
+                  validator: (v) => v == null || v.isEmpty ? 'Sonde ID is required' : null,
+                  onChanged: (value) => widget.data.sondeId = value,
+                  onSaved: (v) => widget.data.sondeId = v,
+                );
+              },
+            ),
+            const SizedBox(height: 16),
+            Row(
+              children: [
+                Expanded(child: TextFormField(controller: _dateController, readOnly: true, decoration: const InputDecoration(labelText: 'Date'))),
+                const SizedBox(width: 16),
+                Expanded(child: TextFormField(controller: _timeController, readOnly: true, decoration: const InputDecoration(labelText: 'Time'))),
+              ],
+            ),
+
+            if (_previousReadingsForComparison != null)
+              _buildComparisonView(),
+
+            const Divider(height: 32),
+            Column(
+              children: _parameters.map((param) {
+                return _buildParameterListItem(
+                  icon: param['icon'] as IconData,
+                  label: param['label'] as String,
+                  unit: param['unit'] as String,
+                  controller: param['controller'] as TextEditingController,
+                  isOutOfBounds: _outOfBoundsKeys.contains(param['key']),
+                );
+              }).toList(),
+            ),
+            const SizedBox(height: 32),
+            ElevatedButton(
+              onPressed: _isLockedOut ? null : _validateAndProceed,
+              style: ElevatedButton.styleFrom(padding: const EdgeInsets.symmetric(vertical: 16)),
+              child: Text(_isLockedOut ? 'Next ($_lockoutSecondsRemaining\s)' : 'Next'),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildComparisonView() {
+    final previousReadings = _previousReadingsForComparison!;
+    final isDarkTheme = Theme.of(context).brightness == Brightness.dark;
+
+    return Card(
+      margin: const EdgeInsets.only(top: 24.0),
+      color: Theme.of(context).cardColor,
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: DefaultTextStyle(
+          style: TextStyle(color: Theme.of(context).textTheme.bodyLarge?.color),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              Text(
+                "Resample Comparison",
+                style: Theme.of(context).textTheme.titleLarge?.copyWith(color: Theme.of(context).primaryColor),
+              ),
+              const SizedBox(height: 8),
+              Table(
+                columnWidths: const {
+                  0: FlexColumnWidth(2),
+                  1: FlexColumnWidth(1.5),
+                  2: FlexColumnWidth(1.5),
+                },
+                border: TableBorder(
+                  horizontalInside: BorderSide(width: 1, color: Colors.grey.shade700, style: BorderStyle.solid),
+                  verticalInside: BorderSide(width: 1, color: Colors.grey.shade700, style: BorderStyle.solid),
+                  top: BorderSide(width: 1.5, color: Colors.grey.shade500),
+                  bottom: BorderSide(width: 1.5, color: Colors.grey.shade500),
+                ),
+                children: [
+                  TableRow(
+                    decoration: BoxDecoration(color: isDarkTheme ? Colors.grey.shade800 : Colors.grey.shade200),
+                    children: [
+                      Padding(padding: const EdgeInsets.all(8.0), child: Text('Parameter', style: TextStyle(fontWeight: FontWeight.bold, color: Theme.of(context).textTheme.titleMedium?.color))),
+                      Padding(padding: const EdgeInsets.all(8.0), child: Text('Previous', style: TextStyle(fontWeight: FontWeight.bold, color: Theme.of(context).textTheme.titleMedium?.color))),
+                      Padding(padding: const EdgeInsets.all(8.0), child: Text('Current', style: TextStyle(fontWeight: FontWeight.bold, color: Theme.of(context).textTheme.titleMedium?.color))),
+                    ],
+                  ),
+                  ..._parameters.map((param) {
+                    final key = param['key'] as String;
+                    final label = param['label'] as String;
+                    final controller = param['controller'] as TextEditingController;
+                    final previousValue = previousReadings[key];
+                    final bool isCurrentValueOutOfBounds = _outOfBoundsKeys.contains(key);
+
+                    return TableRow(
+                      children: [
+                        Padding(padding: const EdgeInsets.all(8.0), child: Text(label)),
+                        Padding(
+                          padding: const EdgeInsets.all(8.0),
+                          child: Text(
+                            previousValue == -999.0 ? '-.--' : previousValue!.toStringAsFixed(5),
+                            style: TextStyle(color: isDarkTheme ? Colors.orange.shade200 : Colors.orange.shade700),
+                          ),
+                        ),
+                        Padding(
+                          padding: const EdgeInsets.all(8.0),
+                          child: Text(
+                            controller.text.contains('-999') ? '-.--' : (double.tryParse(controller.text) ?? 0).toStringAsFixed(5),
+                            style: TextStyle(
+                                color: isCurrentValueOutOfBounds
+                                    ? Colors.red
+                                    : (isDarkTheme ? Colors.green.shade200 : Colors.green.shade700),
+                                fontWeight: FontWeight.bold
+                            ),
+                          ),
+                        ),
+                      ],
+                    );
+                  }).toList(),
+                ],
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Future<void> _showParameterLimitDialog(List<Map<String, dynamic>> invalidParams, Map<String, double> readings) async {
+    return showDialog(
+      context: context,
+      barrierDismissible: false,
+      builder: (BuildContext context) {
+        final isDarkTheme = Theme.of(context).brightness == Brightness.dark;
+        return AlertDialog(
+          title: const Text('Parameter Limit Warning'),
+          content: SingleChildScrollView(
+            child: DefaultTextStyle(
+              style: TextStyle(color: Theme.of(context).textTheme.bodyMedium?.color),
+              child: Column(
+                mainAxisSize: MainAxisSize.min,
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  const Text('The following parameters are outside the standard limits:'),
+                  const SizedBox(height: 16),
+                  Table(
+                    columnWidths: const {
+                      0: FlexColumnWidth(2),
+                      1: FlexColumnWidth(2.5),
+                      2: FlexColumnWidth(1.5),
+                    },
+                    border: TableBorder(
+                      horizontalInside: BorderSide(width: 0.5, color: isDarkTheme ? Colors.grey.shade700 : Colors.grey.shade300),
+                      verticalInside: BorderSide(width: 0.5, color: isDarkTheme ? Colors.grey.shade700 : Colors.grey.shade300),
+                      top: BorderSide(width: 1, color: isDarkTheme ? Colors.grey.shade600 : Colors.grey.shade400),
+                      bottom: BorderSide(width: 1, color: isDarkTheme ? Colors.grey.shade600 : Colors.grey.shade400),
+                    ),
+                    children: [
+                      TableRow(
+                        decoration: BoxDecoration(color: isDarkTheme ? Colors.grey.shade800 : Colors.grey.shade200),
+                        children: [
+                          Padding(padding: const EdgeInsets.all(6.0), child: Text('Parameter', style: TextStyle(fontWeight: FontWeight.bold, color: Theme.of(context).textTheme.titleSmall?.color))),
+                          Padding(padding: const EdgeInsets.all(6.0), child: Text('Limit Range', style: TextStyle(fontWeight: FontWeight.bold, color: Theme.of(context).textTheme.titleSmall?.color))),
+                          Padding(padding: const EdgeInsets.all(6.0), child: Text('Current', style: TextStyle(fontWeight: FontWeight.bold, color: Theme.of(context).textTheme.titleSmall?.color))),
+                        ],
+                      ),
+                      ...invalidParams.map((p) => TableRow(
+                        children: [
+                          Padding(padding: const EdgeInsets.all(6.0), child: Text(p['label'])),
+                          Padding(padding: const EdgeInsets.all(6.0), child: Text('${p['lower_limit']?.toStringAsFixed(5) ?? 'N/A'} - ${p['upper_limit']?.toStringAsFixed(5) ?? 'N/A'}')),
+                          Padding(
+                            padding: const EdgeInsets.all(6.0),
+                            child: Text(
+                              p['value'].toStringAsFixed(5),
+                              style: const TextStyle(color: Colors.redAccent, fontWeight: FontWeight.bold),
+                            ),
+                          ),
+                        ],
+                      )).toList(),
+                    ],
+                  ),
+                  const SizedBox(height: 16),
+                  const Text('Please verify with standard solutions. Do you want to resample or proceed with the current values?'),
+                ],
+              ),
+            ),
+          ),
+          actions: <Widget>[
+            TextButton(
+              child: const Text('Resample'),
+              onPressed: () {
+                setState(() {
+                  _previousReadingsForComparison = readings;
+                });
+                Navigator.of(context).pop();
+              },
+            ),
+            FilledButton(
+              child: const Text('Proceed Anyway'),
+              onPressed: () {
+                Navigator.of(context).pop();
+                _saveDataAndMoveOn(readings);
+              },
+            ),
+          ],
+        );
+      },
+    );
+  }
+
+  Widget _buildParameterListItem({required IconData icon, required String label, required String unit, required TextEditingController controller, bool isOutOfBounds = false}) {
+    final bool isMissing = controller.text.isEmpty || controller.text.contains('-999');
+    final String displayValue = isMissing ? '-.--' : controller.text;
+    final String displayLabel = unit.isEmpty ? label : '$label ($unit)';
+
+    final Color valueColor = isOutOfBounds
+        ? Colors.red
+        : (isMissing ? Colors.grey : Theme.of(context).colorScheme.primary);
+
+    return Card(
+      margin: const EdgeInsets.symmetric(vertical: 4.0),
+      child: ListTile(
+        leading: Icon(icon, color: Theme.of(context).primaryColor, size: 32),
+        title: Text(displayLabel),
+        trailing: Text(
+          displayValue,
+          style: Theme.of(context).textTheme.titleMedium?.copyWith(
+              fontWeight: FontWeight.bold,
+              color: valueColor),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildConnectionCard({required String type, required dynamic connectionState, String? deviceName}) {
+    final isConnected = connectionState == BluetoothConnectionState.connected || connectionState == SerialConnectionState.connected;
+    final isConnecting = connectionState == BluetoothConnectionState.connecting || connectionState == SerialConnectionState.connecting;
+    Color statusColor = isConnected ? Colors.green : Colors.red;
+    String statusText = isConnected ? 'Connected to ${deviceName ?? 'device'}' : 'Disconnected';
+    if (isConnecting) {
+      statusColor = Colors.orange;
+      statusText = 'Connecting...';
+    }
+    return Card(
+      elevation: 2,
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          children: [
+            Text(statusText, style: TextStyle(color: statusColor, fontWeight: FontWeight.bold, fontSize: 16)),
+            const SizedBox(height: 16),
+            if (isConnecting || _isLoading)
+              const CircularProgressIndicator()
+            else if (isConnected)
+              Row(
+                mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+                children: [
+                  ElevatedButton.icon(
+                    icon: Icon(_isAutoReading ? Icons.stop_circle_outlined : Icons.play_circle_outlined),
+                    label: Text(_isAutoReading
+                        ? (_isLockedOut ? 'Stop Reading ($_lockoutSecondsRemaining\s)' : 'Stop Reading')
+                        : 'Start Reading'),
+                    onPressed: (_isAutoReading && _isLockedOut) ? null : () => _toggleAutoReading(type),
+                    style: ElevatedButton.styleFrom(
+                      backgroundColor: _isAutoReading
+                          ? (_isLockedOut ? Colors.grey.shade600 : Colors.orange)
+                          : Colors.green,
+                      foregroundColor: Colors.white,
+                    ),
+                  ),
+                  TextButton.icon(
+                    icon: const Icon(Icons.link_off),
+                    label: const Text('Disconnect'),
+                    onPressed: () => _disconnect(type),
+                    style: TextButton.styleFrom(foregroundColor: Colors.red),
+                  )
+                ],
+              )
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_4_summary.dart

@@ -1 +1,484 @@
 // lib/screens/marine/investigative/manual_sampling/marine_inves_manual_step_4_summary.dart
+
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import '../../../../auth_provider.dart';
+import '../../../../models/marine_inves_manual_sampling_data.dart';
+// REMOVED: Import for NPE Report Screen is no longer needed
+// import '../reports/npe_report_from_investigative.dart';
+
+class MarineInvesManualStep4Summary extends StatefulWidget {
+  final MarineInvesManualSamplingData data;
+  final Future<Map<String, dynamic>> Function()
+  onSubmit; // Expects a function that returns the submission result
+  final bool isLoading;
+
+  const MarineInvesManualStep4Summary({
+    super.key,
+    required this.data,
+    required this.onSubmit,
+    required this.isLoading,
+  });
+
+  @override
+  State<MarineInvesManualStep4Summary> createState() => _MarineInvesManualStep4SummaryState();
+}
+
+class _MarineInvesManualStep4SummaryState extends State<MarineInvesManualStep4Summary> {
+  bool _isHandlingSubmit = false;
+
+  // Keep parameter names for highlighting out-of-bounds station limits
+  static const Map<String, String> _parameterKeyToLimitName = {
+    'oxygenConcentration': 'Oxygen Conc',
+    'oxygenSaturation': 'Oxygen Sat',
+    'ph': 'pH',
+    'salinity': 'Salinity',
+    'electricalConductivity': 'Conductivity',
+    'temperature': 'Temperature',
+    'tds': 'TDS',
+    'turbidity': 'Turbidity',
+    'tss': 'TSS',
+    'batteryVoltage': 'Battery',
+  };
+
+  // Keep this function to highlight parameters outside *station* limits
+  Set<String> _getOutOfBoundsKeys(BuildContext context) {
+    final authProvider = Provider.of<AuthProvider>(context, listen: false);
+    // Use regular marine limits, not NPE limits
+    final marineLimits = authProvider.marineParameterLimits ?? [];
+    final Set<String> invalidKeys = {};
+
+    int? stationId;
+    if (widget.data.stationTypeSelection == 'Existing Manual Station') {
+      stationId = widget.data.selectedStation?['station_id'];
+    }
+    // Note: Only checking against manual station limits for now.
+
+    final readings = {
+      'oxygenConcentration': widget.data.oxygenConcentration,
+      'oxygenSaturation': widget.data.oxygenSaturation,
+      'ph': widget.data.ph,
+      'salinity': widget.data.salinity,
+      'electricalConductivity': widget.data.electricalConductivity,
+      'temperature': widget.data.temperature,
+      'tds': widget.data.tds,
+      'turbidity': widget.data.turbidity,
+      'tss': widget.data.tss,
+      'batteryVoltage': widget.data.batteryVoltage,
+    };
+
+    double? parseLimitValue(dynamic value) {
+      if (value == null) return null;
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    readings.forEach((key, value) {
+      if (value == null || value == -999.0) return;
+
+      final limitName = _parameterKeyToLimitName[key];
+      if (limitName == null) return;
+
+      Map<String, dynamic> limitData = {};
+
+      if (stationId != null) {
+        limitData = marineLimits.firstWhere(
+              (l) =>
+          l['param_parameter_list'] == limitName &&
+              l['station_id'] == stationId,
+          orElse: () => {},
+        );
+      }
+
+      if (limitData.isNotEmpty) {
+        final lowerLimit = parseLimitValue(limitData['param_lower_limit']);
+        final upperLimit = parseLimitValue(limitData['param_upper_limit']);
+
+        if ((lowerLimit != null && value < lowerLimit) ||
+            (upperLimit != null && value > upperLimit)) {
+          invalidKeys.add(key);
+        }
+      }
+    });
+
+    return invalidKeys;
+  }
+
+  // REMOVED: _getNpeTriggeredParameters method
+  // REMOVED: _showNpeDialog method
+
+  /// Handles the complete submission flow WITHOUT NPE check.
+  Future<void> _handleSubmit(BuildContext context) async {
+    if (_isHandlingSubmit || widget.isLoading) return;
+
+    setState(() => _isHandlingSubmit = true);
+
+    try {
+      // Directly call the submission function provided by the parent
+      final result = await widget.onSubmit();
+      if (!mounted) return;
+
+      // Show feedback snackbar based on the result
+      final message = result['message'] ?? 'An unknown error occurred.';
+      final color = (result['success'] == true) ? Colors.green : Colors.red;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+            content: Text(message),
+            backgroundColor: color,
+            duration: const Duration(seconds: 4)),
+      );
+
+      // If submission was successful, navigate back to the home screen
+      if (result['success'] == true) {
+        Navigator.of(context).popUntil((route) => route.isFirst);
+      }
+      // If submission failed, the user stays on the summary screen to potentially retry
+
+    } catch (e) {
+      // Catch any unexpected errors during submission
+      if (mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(
+              content: Text('Submission failed unexpectedly: $e'),
+              backgroundColor: Colors.red,
+              duration: const Duration(seconds: 4)),
+        );
+      }
+    } finally {
+      // Ensure the loading state is turned off
+      if (mounted) {
+        setState(() => _isHandlingSubmit = false);
+      }
+    }
+  }
+
+  // Helper to build station details dynamically
+  List<Widget> _buildStationDetails() {
+    final stationType = widget.data.stationTypeSelection;
+
+    if (stationType == 'Existing Manual Station') {
+      return [
+        _buildDetailRow("Station Source:", "Existing Manual Station"),
+        _buildDetailRow("State:", widget.data.selectedManualStateName),
+        _buildDetailRow("Category:", widget.data.selectedManualCategoryName),
+        _buildDetailRow("Station ID:", widget.data.selectedStation?['man_station_code']?.toString()),
+        _buildDetailRow("Station Name:", widget.data.selectedStation?['man_station_name']?.toString()),
+        _buildDetailRow("Station Location:", "${widget.data.stationLatitude}, ${widget.data.stationLongitude}"),
+      ];
+    } else if (stationType == 'Existing Tarball Station') {
+      return [
+        _buildDetailRow("Station Source:", "Existing Tarball Station"),
+        _buildDetailRow("State:", widget.data.selectedTarballStateName),
+        _buildDetailRow("Station ID:", widget.data.selectedTarballStation?['tbl_station_code']?.toString()),
+        _buildDetailRow("Station Name:", widget.data.selectedTarballStation?['tbl_station_name']?.toString()),
+        _buildDetailRow("Station Location:", "${widget.data.stationLatitude}, ${widget.data.stationLongitude}"),
+      ];
+    } else if (stationType == 'New Location') {
+      return [
+        _buildDetailRow("Station Source:", "New Location"),
+        _buildDetailRow("Station Name:", widget.data.newStationName),
+        _buildDetailRow("Station Code:", widget.data.newStationCode),
+        _buildDetailRow("Station Location:", "(Manual) ${widget.data.stationLatitude}, ${widget.data.stationLongitude}"),
+      ];
+    }
+    return [_buildDetailRow("Station Info:", "Not specified")];
+  }
+
+
+  @override
+  Widget build(BuildContext context) {
+    // Still get out-of-bounds keys for station limits to highlight them
+    final outOfBoundsKeys = _getOutOfBoundsKeys(context);
+
+    return ListView(
+      padding: const EdgeInsets.all(16.0),
+      children: [
+        Text(
+          "Please review all information before submitting.",
+          style: Theme.of(context).textTheme.titleMedium,
+          textAlign: TextAlign.center,
+        ),
+        const SizedBox(height: 16),
+        _buildSectionCard(
+          context,
+          "Sampling & Station Details",
+          [
+            _buildDetailRow("1st Sampler:", widget.data.firstSamplerName),
+            _buildDetailRow(
+                "2nd Sampler:", widget.data.secondSampler?['first_name']?.toString()),
+            _buildDetailRow("Sampling Date:", widget.data.samplingDate),
+            _buildDetailRow("Sampling Time:", widget.data.samplingTime),
+            _buildDetailRow("Sampling Type:", widget.data.samplingType),
+            _buildDetailRow("Sample ID Code:", widget.data.sampleIdCode),
+            const Divider(height: 20),
+            ..._buildStationDetails(), // Use dynamic station details
+          ],
+        ),
+        _buildSectionCard(
+          context,
+          "Location & On-Site Info",
+          [
+            _buildDetailRow("Current Location:",
+                "${widget.data.currentLatitude}, ${widget.data.currentLongitude}"),
+            _buildDetailRow(
+                "Distance Difference:",
+                widget.data.distanceDifferenceInKm != null
+                    ? "${(widget.data.distanceDifferenceInKm! * 1000).toStringAsFixed(0)} meters"
+                    : "N/A"),
+            if (widget.data.distanceDifferenceRemarks != null &&
+                widget.data.distanceDifferenceRemarks!.isNotEmpty)
+              _buildDetailRow(
+                  "Distance Remarks:", widget.data.distanceDifferenceRemarks),
+            const Divider(height: 20),
+            _buildDetailRow("Weather:", widget.data.weather),
+            _buildDetailRow("Tide Level:", widget.data.tideLevel),
+            _buildDetailRow("Sea Condition:", widget.data.seaCondition),
+            _buildDetailRow("Event Remarks:", widget.data.eventRemarks),
+            _buildDetailRow("Lab Remarks:", widget.data.labRemarks),
+          ],
+        ),
+        _buildSectionCard(
+          context,
+          "Attached Photos",
+          [
+            _buildImageCard("Left Side Land View", widget.data.leftLandViewImage),
+            _buildImageCard(
+                "Right Side Land View", widget.data.rightLandViewImage),
+            _buildImageCard(
+                "Filling Water into Bottle", widget.data.waterFillingImage),
+            _buildImageCard(
+                "Seawater Color in Bottle", widget.data.seawaterColorImage),
+            _buildImageCard(
+                "Examine Preservative (pH paper)", widget.data.phPaperImage),
+            const Divider(height: 24),
+            Text("Optional Photos",
+                style: Theme.of(context)
+                    .textTheme
+                    .titleMedium
+                    ?.copyWith(fontWeight: FontWeight.bold)),
+            const SizedBox(height: 8),
+            _buildImageCard("Optional Photo 1", widget.data.optionalImage1,
+                remark: widget.data.optionalRemark1),
+            _buildImageCard("Optional Photo 2", widget.data.optionalImage2,
+                remark: widget.data.optionalRemark2),
+            _buildImageCard("Optional Photo 3", widget.data.optionalImage3,
+                remark: widget.data.optionalRemark3),
+            _buildImageCard("Optional Photo 4", widget.data.optionalImage4,
+                remark: widget.data.optionalRemark4),
+          ],
+        ),
+        _buildSectionCard(
+          context,
+          "Captured Parameters",
+          [
+            _buildDetailRow("Sonde ID:", widget.data.sondeId),
+            _buildDetailRow("Capture Time:",
+                "${widget.data.dataCaptureDate} ${widget.data.dataCaptureTime}"),
+            const Divider(height: 20),
+            _buildParameterListItem(context,
+                icon: Icons.air,
+                label: "Oxygen Conc.",
+                unit: "mg/L",
+                value: widget.data.oxygenConcentration,
+                isOutOfBounds:
+                outOfBoundsKeys.contains('oxygenConcentration')),
+            _buildParameterListItem(context,
+                icon: Icons.percent,
+                label: "Oxygen Sat.",
+                unit: "%",
+                value: widget.data.oxygenSaturation,
+                isOutOfBounds: outOfBoundsKeys.contains('oxygenSaturation')),
+            _buildParameterListItem(context,
+                icon: Icons.science_outlined,
+                label: "pH",
+                unit: "",
+                value: widget.data.ph,
+                isOutOfBounds: outOfBoundsKeys.contains('ph')),
+            _buildParameterListItem(context,
+                icon: Icons.waves,
+                label: "Salinity",
+                unit: "ppt",
+                value: widget.data.salinity,
+                isOutOfBounds: outOfBoundsKeys.contains('salinity')),
+            _buildParameterListItem(context,
+                icon: Icons.flash_on,
+                label: "Conductivity",
+                unit: "µS/cm",
+                value: widget.data.electricalConductivity,
+                isOutOfBounds:
+                outOfBoundsKeys.contains('electricalConductivity')),
+            _buildParameterListItem(context,
+                icon: Icons.thermostat,
+                label: "Temperature",
+                unit: "°C",
+                value: widget.data.temperature,
+                isOutOfBounds: outOfBoundsKeys.contains('temperature')),
+            _buildParameterListItem(context,
+                icon: Icons.grain,
+                label: "TDS",
+                unit: "mg/L",
+                value: widget.data.tds,
+                isOutOfBounds: outOfBoundsKeys.contains('tds')),
+            _buildParameterListItem(context,
+                icon: Icons.opacity,
+                label: "Turbidity",
+                unit: "NTU",
+                value: widget.data.turbidity,
+                isOutOfBounds: outOfBoundsKeys.contains('turbidity')),
+            _buildParameterListItem(context,
+                icon: Icons.filter_alt_outlined,
+                label: "TSS",
+                unit: "mg/L",
+                value: widget.data.tss,
+                isOutOfBounds: outOfBoundsKeys.contains('tss')),
+            _buildParameterListItem(context,
+                icon: Icons.battery_charging_full,
+                label: "Battery",
+                unit: "V",
+                value: widget.data.batteryVoltage,
+                isOutOfBounds: outOfBoundsKeys.contains('batteryVoltage')),
+          ],
+        ),
+        const SizedBox(height: 24),
+        (widget.isLoading || _isHandlingSubmit)
+            ? const Center(child: CircularProgressIndicator())
+            : ElevatedButton.icon(
+          onPressed: () => _handleSubmit(context), // Simplified call
+          icon: const Icon(Icons.cloud_upload),
+          label: const Text('Confirm & Submit'),
+          style: ElevatedButton.styleFrom(
+            padding: const EdgeInsets.symmetric(vertical: 16),
+            textStyle: const TextStyle(
+                fontSize: 18, fontWeight: FontWeight.bold),
+          ),
+        ),
+        const SizedBox(height: 16),
+      ],
+    );
+  }
+
+  // --- Helper widgets ---
+  Widget _buildSectionCard(
+      BuildContext context, String title, List<Widget> children) {
+    return Card(
+      margin: const EdgeInsets.symmetric(vertical: 8.0),
+      elevation: 2,
+      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(
+              title,
+              style: TextStyle(
+                fontSize: 18,
+                fontWeight: FontWeight.bold,
+                color: Theme.of(context).primaryColor,
+              ),
+            ),
+            const Divider(height: 20, thickness: 1),
+            ...children,
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildDetailRow(String label, String? value) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 6.0),
+      child: Row(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Expanded(
+            flex: 2,
+            child: Text(label, style: const TextStyle(fontWeight: FontWeight.bold)),
+          ),
+          const SizedBox(width: 8),
+          Expanded(
+            flex: 3,
+            child: Text(value != null && value.isNotEmpty ? value : 'N/A',
+                style: const TextStyle(fontSize: 16)),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildParameterListItem(BuildContext context,
+      {required IconData icon,
+        required String label,
+        required String unit,
+        required double? value,
+        bool isOutOfBounds = false}) {
+    final bool isMissing = value == null || value == -999.0;
+    final String displayValue =
+    isMissing ? 'N/A' : '${value.toStringAsFixed(5)} ${unit}'.trim();
+    final Color? defaultTextColor =
+        Theme.of(context).textTheme.bodyLarge?.color;
+    final Color valueColor = isOutOfBounds // Still highlight if outside station limits
+        ? Colors.red
+        : (isMissing ? Colors.grey : defaultTextColor ?? Colors.black);
+
+    return ListTile(
+      dense: true,
+      contentPadding: EdgeInsets.zero,
+      leading: Icon(icon, color: Theme.of(context).primaryColor, size: 28),
+      title: Text(label, style: const TextStyle(fontWeight: FontWeight.bold)),
+      trailing: Text(
+        displayValue,
+        style: Theme.of(context).textTheme.bodyLarge?.copyWith(
+          color: valueColor,
+          fontWeight: isOutOfBounds ? FontWeight.bold : null,
+        ),
+      ),
+    );
+  }
+
+  Widget _buildImageCard(String title, File? image, {String? remark}) {
+    final bool hasRemark = remark != null && remark.isNotEmpty;
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 8.0),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(title,
+              style:
+              const TextStyle(fontWeight: FontWeight.bold, fontSize: 16)),
+          const SizedBox(height: 8),
+          if (image != null)
+            ClipRRect(
+              borderRadius: BorderRadius.circular(8.0),
+              child: Image.file(image,
+                  key: UniqueKey(),
+                  height: 200,
+                  width: double.infinity,
+                  fit: BoxFit.cover),
+            )
+          else
+            Container(
+              height: 100,
+              width: double.infinity,
+              decoration: BoxDecoration(
+                  color: Colors.grey[200],
+                  borderRadius: BorderRadius.circular(8.0),
+                  border: Border.all(color: Colors.grey[300]!)),
+              child: const Center(
+                  child: Text('No Image Attached',
+                      style: TextStyle(color: Colors.grey))),
+            ),
+          if (hasRemark)
+            Padding(
+              padding: const EdgeInsets.only(top: 8.0),
+              child: Text('Remark: $remark',
+                  style: const TextStyle(fontStyle: FontStyle.italic)),
+            ),
+        ],
+      ),
+    );
+  }
+}

lib/screens/marine/investigative/marine_investigative_manual_sampling.dart

@@ -1 +1,125 @@
 // lib/screens/marine/investigative/marine_investigative_manual_sampling.dart
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import '../../../models/marine_inves_manual_sampling_data.dart';
+import '../../../services/marine_investigative_sampling_service.dart';
+import '../../../auth_provider.dart';
+
+import 'manual_sampling/marine_inves_manual_step_1_sampling_info.dart';
+import 'manual_sampling/marine_inves_manual_step_2_site_info.dart';
+import 'manual_sampling/marine_inves_manual_step_3_data_capture.dart';
+import 'manual_sampling/marine_inves_manual_step_4_summary.dart';
+
+class MarineInvestigativeManualSampling extends StatefulWidget {
+  const MarineInvestigativeManualSampling({super.key});
+
+  @override
+  State<MarineInvestigativeManualSampling> createState() => _MarineInvestigativeManualSamplingState();
+}
+
+class _MarineInvestigativeManualSamplingState extends State<MarineInvestigativeManualSampling> {
+  final PageController _pageController = PageController();
+  final MarineInvesManualSamplingData _data = MarineInvesManualSamplingData();
+  int _currentStep = 0;
+  bool _isLoading = false;
+
+  @override
+  void initState() {
+    super.initState();
+    // Pre-fill sampling date and time when the form is first created
+    final now = DateTime.now();
+    _data.samplingDate = "${now.year}-${now.month.toString().padLeft(2, '0')}-${now.day.toString().padLeft(2, '0')}";
+    _data.samplingTime = "${now.hour.toString().padLeft(2, '0')}:${now.minute.toString().padLeft(2, '0')}:${now.second.toString().padLeft(2, '0')}";
+  }
+
+  @override
+  void dispose() {
+    _pageController.dispose();
+    super.dispose();
+  }
+
+  void _nextPage() {
+    if (_currentStep < 3) {
+      _pageController.nextPage(
+        duration: const Duration(milliseconds: 300),
+        curve: Curves.easeInOut,
+      );
+    }
+  }
+
+  void _previousPage() {
+    if (_currentStep > 0) {
+      _pageController.previousPage(
+        duration: const Duration(milliseconds: 300),
+        curve: Curves.easeInOut,
+      );
+    }
+  }
+
+  Future<Map<String, dynamic>> _submitData() async {
+    setState(() => _isLoading = true);
+
+    final service = context.read<MarineInvestigativeSamplingService>();
+    final authProvider = context.read<AuthProvider>();
+    final appSettings = authProvider.appSettings;
+
+    try {
+      final result = await service.submitInvestigativeSample(
+        data: _data,
+        appSettings: appSettings,
+        authProvider: authProvider,
+        context: context,
+      );
+
+      return result;
+
+    } catch (e) {
+      return {'success': false, 'message': 'An unexpected error occurred: $e'};
+    } finally {
+      if (mounted) {
+        setState(() => _isLoading = false);
+      }
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final List<Widget> pages = [
+      MarineInvesManualStep1SamplingInfo(data: _data, onNext: _nextPage),
+      MarineInvesManualStep2SiteInfo(data: _data, onNext: _nextPage),
+      MarineInvesManualStep3DataCapture(data: _data, onNext: _nextPage),
+      MarineInvesManualStep4Summary(
+        data: _data,
+        onSubmit: _submitData,
+        isLoading: _isLoading,
+      ),
+    ];
+
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Marine Investigative Sampling (Step ${_currentStep + 1} of 4)'),
+        leading: _currentStep == 0
+            ? IconButton(
+          icon: const Icon(Icons.close),
+          onPressed: () => Navigator.of(context).pop(),
+        )
+            : IconButton(
+          icon: const Icon(Icons.arrow_back),
+          onPressed: _previousPage,
+        ),
+      ),
+      body: PageView(
+        controller: _pageController,
+        physics: const NeverScrollableScrollPhysics(),
+        onPageChanged: (index) {
+          setState(() {
+            _currentStep = index;
+          });
+        },
+        children: pages,
+      ),
+    );
+  }
+}

lib/screens/marine/marine_home_page.dart

@@ -1,3 +1,5 @@
+// lib/screens/marine/marine_home_page.dart
+
 import 'package:flutter/material.dart';
 
 // Re-defining SidebarItem here for self-containment,
@@ -60,6 +62,8 @@ class MarineHomePage extends StatelessWidget {
       children: [
         // MODIFIED: Updated label, icon, and route for the new Info Centre screen
         SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/marine/investigative/info'),
+        // *** ADDED: New menu item for Investigative Manual Sampling ***
+        SidebarItem(icon: Icons.science_outlined, label: "Investigative Sampling", route: '/marine/investigative/manual-sampling'),
         //SidebarItem(icon: Icons.info, label: "Overview", route: '/marine/investigative/overview'),
         //SidebarItem(icon: Icons.input, label: "Entry", route: '/marine/investigative/entry'),
         //SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/marine/investigative/report'),

lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_1_sampling_info.dart

@@ -0,0 +1,877 @@
+// lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_1_sampling_info.dart
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:dropdown_search/dropdown_search.dart';
+import 'package:intl/intl.dart';
+import 'package:simple_barcode_scanner/simple_barcode_scanner.dart';
+
+import '../../../../auth_provider.dart';
+import '../../../../models/river_inves_manual_sampling_data.dart'; // Updated model
+import '../../../../services/river_investigative_sampling_service.dart'; // Updated service
+
+class RiverInvesStep1SamplingInfo extends StatefulWidget {
+  final RiverInvesManualSamplingData data;
+  final VoidCallback onNext;
+
+  const RiverInvesStep1SamplingInfo({
+    super.key,
+    required this.data,
+    required this.onNext,
+  });
+
+  @override
+  State<RiverInvesStep1SamplingInfo> createState() =>
+      _RiverInvesStep1SamplingInfoState();
+}
+
+class _RiverInvesStep1SamplingInfoState extends State<RiverInvesStep1SamplingInfo> {
+  final _formKey = GlobalKey<FormState>();
+  bool _isLoadingLocation = false;
+
+  late final TextEditingController _firstSamplerController;
+  late final TextEditingController _dateController;
+  late final TextEditingController _timeController;
+  late final TextEditingController _barcodeController;
+  late final TextEditingController _stationLatController;
+  late final TextEditingController _stationLonController;
+  late final TextEditingController _currentLatController;
+  late final TextEditingController _currentLonController;
+
+  // --- NEW: Controllers for New Location ---
+  late final TextEditingController _newStateController;
+  late final TextEditingController _newBasinController;
+  late final TextEditingController _newRiverController;
+  late final TextEditingController _newStationCodeController;
+
+  List<String> _statesList = [];
+  List<Map<String, dynamic>> _manualStationsForState = [];
+  List<Map<String, dynamic>> _triennialStationsForState = [];
+  final List<String> _stationTypes = [
+    'Existing Manual Station',
+    'Existing Triennial Station',
+    'New Location'
+  ];
+  // Note: Investigative sampling type is fixed in the model
+
+  @override
+  void initState() {
+    super.initState();
+    _initializeControllers();
+    _initializeForm();
+  }
+
+  @override
+  void dispose() {
+    _firstSamplerController.dispose();
+    _dateController.dispose();
+    _timeController.dispose();
+    _barcodeController.dispose();
+    _stationLatController.dispose();
+    _stationLonController.dispose();
+    _currentLatController.dispose();
+    _currentLonController.dispose();
+    _newStateController.dispose();
+    _newBasinController.dispose();
+    _newRiverController.dispose();
+    _newStationCodeController.dispose();
+    super.dispose();
+  }
+
+  void _initializeControllers() {
+    _firstSamplerController = TextEditingController();
+    _dateController = TextEditingController();
+    _timeController = TextEditingController();
+    _barcodeController = TextEditingController(text: widget.data.sampleIdCode);
+    _stationLatController = TextEditingController(text: widget.data.stationLatitude);
+    _stationLonController = TextEditingController(text: widget.data.stationLongitude);
+    _currentLatController = TextEditingController(text: widget.data.currentLatitude);
+    _currentLonController = TextEditingController(text: widget.data.currentLongitude);
+    // New Location controllers
+    _newStateController = TextEditingController(text: widget.data.newStateName);
+    _newBasinController = TextEditingController(text: widget.data.newBasinName);
+    _newRiverController = TextEditingController(text: widget.data.newRiverName);
+    _newStationCodeController = TextEditingController(text: widget.data.newStationCode);
+  }
+
+  void _initializeForm() {
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+
+    widget.data.firstSamplerName = auth.profileData?['first_name'] ?? 'Current User';
+    widget.data.firstSamplerUserId = auth.profileData?['user_id'];
+    _firstSamplerController.text = widget.data.firstSamplerName!;
+
+    final now = DateTime.now();
+    if (widget.data.samplingDate == null || widget.data.samplingDate!.isEmpty) {
+      widget.data.samplingDate = DateFormat('yyyy-MM-dd').format(now);
+      widget.data.samplingTime = DateFormat('HH:mm:ss').format(now);
+    }
+    _dateController.text = widget.data.samplingDate!;
+    _timeController.text = widget.data.samplingTime!;
+
+    // Sampling type is fixed to Investigative in the model
+
+    // Populate states list from Manual stations (assuming they cover all states)
+    final allManualStations = auth.riverManualStations ?? [];
+    if (allManualStations.isNotEmpty) {
+      final states = allManualStations
+          .map((s) => s['state_name'] as String?)
+          .whereType<String>()
+          .toSet()
+          .toList();
+      states.sort();
+      setState(() {
+        _statesList = states;
+      });
+    } else {
+      // Fallback: If no manual stations, try getting states from Triennial or general States list
+      final allTriennialStations = auth.riverTriennialStations ?? [];
+      if (allTriennialStations.isNotEmpty) {
+        final states = allTriennialStations
+            .map((s) => s['state_name'] as String?) // Assuming Triennial has state_name
+            .whereType<String>()
+            .toSet()
+            .toList();
+        states.sort();
+        setState(() { _statesList = states; });
+      } else {
+        // Further fallback
+        final generalStates = auth.states ?? [];
+        final states = generalStates
+            .map((s) => s['state_name'] as String?)
+            .whereType<String>()
+            .toSet()
+            .toList();
+        states.sort();
+        setState(() { _statesList = states; });
+      }
+    }
+
+
+    // Pre-load stations if state and type are already selected (e.g., coming back to step)
+    _loadStationsForSelectedState();
+    _calculateDistance(); // Recalculate distance on init
+  }
+
+  void _loadStationsForSelectedState() {
+    if (widget.data.selectedStateName == null) return;
+
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+    final allManualStations = auth.riverManualStations ?? [];
+    final allTriennialStations = auth.riverTriennialStations ?? [];
+
+    setState(() {
+      _manualStationsForState = allManualStations
+          .where((s) => s['state_name'] == widget.data.selectedStateName)
+          .toList()
+        ..sort((a, b) => (a['sampling_station_code'] ?? '')
+            .compareTo(b['sampling_station_code'] ?? ''));
+
+      _triennialStationsForState = allTriennialStations
+          .where((s) => s['state_name'] == widget.data.selectedStateName) // Assuming Triennial has state_name
+          .toList()
+        ..sort((a, b) => (a['triennial_station_code'] ?? '')
+            .compareTo(b['triennial_station_code'] ?? ''));
+    });
+  }
+
+  Future<void> _getCurrentLocation() async {
+    setState(() => _isLoadingLocation = true);
+    final service = Provider.of<RiverInvestigativeSamplingService>(context, listen: false);
+
+    try {
+      final position = await service.getCurrentLocation();
+      if (mounted) {
+        setState(() {
+          widget.data.currentLatitude = position.latitude.toString();
+          widget.data.currentLongitude = position.longitude.toString();
+          _currentLatController.text = widget.data.currentLatitude!;
+          _currentLonController.text = widget.data.currentLongitude!;
+
+          // --- MODIFICATION: Update station lat/lon ONLY if 'New Location' ---
+          if (widget.data.stationTypeSelection == 'New Location') {
+            widget.data.stationLatitude = position.latitude.toString();
+            widget.data.stationLongitude = position.longitude.toString();
+            _stationLatController.text = widget.data.stationLatitude!;
+            _stationLonController.text = widget.data.stationLongitude!;
+          }
+          // --- END MODIFICATION ---
+
+          _calculateDistance(); // Always calculate distance after getting current location
+        });
+      }
+    } catch (e) {
+      if(mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Failed to get location: $e')));
+      }
+    } finally {
+      if (mounted) {
+        setState(() => _isLoadingLocation = false);
+      }
+    }
+  }
+
+
+  void _calculateDistance() {
+    final lat1Str = widget.data.stationLatitude;
+    final lon1Str = widget.data.stationLongitude;
+    final lat2Str = widget.data.currentLatitude;
+    final lon2Str = widget.data.currentLongitude;
+
+    if (lat1Str != null && lon1Str != null && lat2Str != null && lon2Str != null) {
+      final service = Provider.of<RiverInvestigativeSamplingService>(context, listen: false);
+      final lat1 = double.tryParse(lat1Str);
+      final lon1 = double.tryParse(lon1Str);
+      final lat2 = double.tryParse(lat2Str);
+      final lon2 = double.tryParse(lon2Str);
+
+      if (lat1 != null && lon1 != null && lat2 != null && lon2 != null) {
+        final distance = service.calculateDistance(lat1, lon1, lat2, lon2);
+        setState(() {
+          widget.data.distanceDifferenceInKm = distance;
+        });
+      } else {
+        setState(() { widget.data.distanceDifferenceInKm = null; });
+      }
+    } else {
+      setState(() { widget.data.distanceDifferenceInKm = null; });
+    }
+  }
+
+  Future<void> _scanBarcode() async {
+    final result = await Navigator.push(
+      context,
+      MaterialPageRoute(builder: (context) => const SimpleBarcodeScannerPage()),
+    );
+    if (result is String && result != '-1' && mounted) {
+      setState(() {
+        widget.data.sampleIdCode = result;
+        _barcodeController.text = result;
+      });
+    }
+  }
+
+  // --- MODIFICATION: Disable Nearby Station for now, or adapt later ---
+  Future<void> _findAndShowNearbyStations() async {
+    // Only works for Manual Stations currently
+    if (widget.data.stationTypeSelection != 'Existing Manual Station') {
+      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Nearby station search only available for Manual Stations.')));
+      return;
+    }
+
+    if (widget.data.currentLatitude == null || widget.data.currentLatitude!.isEmpty) {
+      await _getCurrentLocation();
+      if (!mounted || widget.data.currentLatitude == null || widget.data.currentLatitude!.isEmpty) {
+        return;
+      }
+    }
+
+    final service = Provider.of<RiverInvestigativeSamplingService>(context, listen: false);
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+
+    final currentLat = double.parse(widget.data.currentLatitude!);
+    final currentLon = double.parse(widget.data.currentLongitude!);
+    final allStations = auth.riverManualStations ?? []; // Only search Manual
+    final List<Map<String, dynamic>> nearbyStations = [];
+
+    for (var station in allStations) {
+      final stationLat = station['sampling_lat'];
+      final stationLon = station['sampling_long'];
+
+      if (stationLat is num && stationLon is num) {
+        final distance = service.calculateDistance(currentLat, currentLon, stationLat.toDouble(), stationLon.toDouble());
+        if (distance <= 3.0) { // 3km radius
+          nearbyStations.add({'station': station, 'distance': distance});
+        }
+      }
+    }
+
+    nearbyStations.sort((a, b) => a['distance'].compareTo(b['distance']));
+
+    if (!mounted) return;
+
+    final selectedStation = await showDialog<Map<String, dynamic>>(
+      context: context,
+      builder: (context) => _NearbyStationsDialog(nearbyStations: nearbyStations), // Use the same dialog
+    );
+
+    if (selectedStation != null) {
+      _updateFormWithSelectedManualStation(selectedStation);
+    }
+  }
+
+  void _updateFormWithSelectedManualStation(Map<String, dynamic> station) {
+    // This specifically handles selecting a MANUAL station from nearby search or dropdown
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+    final allManualStations = auth.riverManualStations ?? [];
+    setState(() {
+      widget.data.stationTypeSelection = 'Existing Manual Station'; // Ensure type is correct
+      widget.data.selectedStateName = station['state_name'];
+      widget.data.selectedStation = station; // Set manual station
+      widget.data.selectedTriennialStation = null; // Clear triennial
+      _clearNewLocationFields(); // Clear new location fields
+
+      widget.data.stationLatitude = station['sampling_lat']?.toString();
+      widget.data.stationLongitude = station['sampling_long']?.toString();
+      _stationLatController.text = widget.data.stationLatitude ?? '';
+      _stationLonController.text = widget.data.stationLongitude ?? '';
+
+      // Reload stations for the selected state if needed (mainly for UI consistency)
+      _manualStationsForState = allManualStations
+          .where((s) => s['state_name'] == widget.data.selectedStateName)
+          .toList()
+        ..sort((a, b) => (a['sampling_station_code'] ?? '').compareTo(b['sampling_station_code'] ?? ''));
+
+      _calculateDistance();
+    });
+  }
+
+  void _updateFormWithSelectedTriennialStation(Map<String, dynamic> station) {
+    // This specifically handles selecting a TRIENNIAL station from dropdown
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+    final allTriennialStations = auth.riverTriennialStations ?? [];
+    setState(() {
+      widget.data.stationTypeSelection = 'Existing Triennial Station';
+      widget.data.selectedStateName = station['state_name']; // Use state from Triennial data
+      widget.data.selectedTriennialStation = station; // Set triennial station
+      widget.data.selectedStation = null; // Clear manual
+      _clearNewLocationFields();
+
+      widget.data.stationLatitude = station['triennial_lat']?.toString(); // Use triennial keys
+      widget.data.stationLongitude = station['triennial_long']?.toString(); // Use triennial keys
+      _stationLatController.text = widget.data.stationLatitude ?? '';
+      _stationLonController.text = widget.data.stationLongitude ?? '';
+
+      // Reload stations for state (UI consistency)
+      _triennialStationsForState = allTriennialStations
+          .where((s) => s['state_name'] == widget.data.selectedStateName)
+          .toList()
+        ..sort((a, b) => (a['triennial_station_code'] ?? '').compareTo(b['triennial_station_code'] ?? ''));
+
+      _calculateDistance();
+    });
+  }
+
+  void _clearStationSelections() {
+    widget.data.selectedStation = null;
+    widget.data.selectedTriennialStation = null;
+    widget.data.stationLatitude = null;
+    widget.data.stationLongitude = null;
+    _stationLatController.clear();
+    _stationLonController.clear();
+    widget.data.distanceDifferenceInKm = null;
+  }
+
+  void _clearNewLocationFields() {
+    widget.data.newStateName = null;
+    widget.data.newBasinName = null;
+    widget.data.newRiverName = null;
+    widget.data.newStationCode = null;
+    _newStateController.clear();
+    _newBasinController.clear();
+    _newRiverController.clear();
+    _newStationCodeController.clear();
+    // Don't clear station lat/lon here, as they might be set by GPS for new location
+  }
+
+
+  void _goToNextStep() {
+    if (_formKey.currentState!.validate()) {
+      _formKey.currentState!.save(); // Save form fields to widget.data
+
+      // --- Additional Validation for New Location ---
+      if (widget.data.stationTypeSelection == 'New Location') {
+        if (widget.data.stationLatitude == null || widget.data.stationLatitude!.isEmpty ||
+            widget.data.stationLongitude == null || widget.data.stationLongitude!.isEmpty ) {
+          ScaffoldMessenger.of(context).showSnackBar(
+              const SnackBar(content: Text('Please capture GPS coordinates for the new location.'), backgroundColor: Colors.red)
+          );
+          return;
+        }
+      }
+      // --- End Additional Validation ---
+
+      final distanceInMeters = (widget.data.distanceDifferenceInKm ?? 0) * 1000;
+
+      // Only show distance warning if NOT a new location and distance > 50m
+      if (widget.data.stationTypeSelection != 'New Location' && distanceInMeters > 50) {
+        _showDistanceRemarkDialog();
+      } else {
+        widget.data.distanceDifferenceRemarks = null; // Clear remark if not needed
+        widget.onNext();
+      }
+    }
+  }
+
+  Future<void> _showDistanceRemarkDialog() async {
+    final remarkController = TextEditingController(text: widget.data.distanceDifferenceRemarks);
+    final dialogFormKey = GlobalKey<FormState>();
+
+    return showDialog<void>(
+      context: context,
+      barrierDismissible: false,
+      builder: (BuildContext context) {
+        return AlertDialog(
+          title: const Text('Distance Warning'),
+          content: SingleChildScrollView(
+            child: Form(
+              key: dialogFormKey,
+              child: Column(
+                mainAxisSize: MainAxisSize.min,
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  const Text('Your current location is more than 50m away from the selected station.'),
+                  const SizedBox(height: 16),
+                  TextFormField(
+                    controller: remarkController,
+                    decoration: const InputDecoration(
+                      labelText: 'Remarks *',
+                      hintText: 'Please provide a reason...',
+                      border: OutlineInputBorder(),
+                    ),
+                    validator: (value) {
+                      if (value == null || value.trim().isEmpty) {
+                        return 'Remarks are required to continue.';
+                      }
+                      return null;
+                    },
+                    maxLines: 3,
+                  ),
+                ],
+              ),
+            ),
+          ),
+          actions: <Widget>[
+            TextButton(
+              child: const Text('Cancel'),
+              onPressed: () {
+                Navigator.of(context).pop();
+              },
+            ),
+            FilledButton(
+              child: const Text('Confirm'),
+              onPressed: () {
+                if (dialogFormKey.currentState!.validate()) {
+                  setState(() {
+                    widget.data.distanceDifferenceRemarks = remarkController.text;
+                  });
+                  Navigator.of(context).pop();
+                  widget.onNext(); // Proceed after confirming remark
+                }
+              },
+            ),
+          ],
+        );
+      },
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+    // Note: Station lists (_manualStationsForState, _triennialStationsForState) are updated in callbacks
+    final allUsers = auth.allUsers ?? [];
+
+    final secondSamplersList = allUsers
+        .where((user) => user['user_id'] != auth.profileData?['user_id'])
+        .toList()
+      ..sort((a, b) =>
+          (a['first_name'] ?? '').compareTo(b['first_name'] ?? ''));
+
+    bool isNewLocation = widget.data.stationTypeSelection == 'New Location';
+
+    return Form(
+      key: _formKey,
+      child: ListView(
+        padding: const EdgeInsets.all(24.0),
+        children: [
+          Text("Investigative Sampling Information",
+              style: Theme.of(context).textTheme.headlineSmall),
+          const SizedBox(height: 24),
+
+          // --- Sampler and Time ---
+          TextFormField(
+              controller: _firstSamplerController,
+              readOnly: true,
+              decoration: const InputDecoration(labelText: '1st Sampler')),
+          const SizedBox(height: 16),
+          DropdownSearch<Map<String, dynamic>>(
+            items: secondSamplersList,
+            selectedItem: widget.data.secondSampler,
+            itemAsString: (sampler) =>
+            "${sampler['first_name']} ${sampler['last_name']}",
+            onChanged: (sampler) => widget.data.secondSampler = sampler,
+            popupProps: const PopupProps.menu(
+                showSearchBox: true,
+                searchFieldProps: TextFieldProps(
+                    decoration: InputDecoration(hintText: "Search Sampler..."))),
+            dropdownDecoratorProps: const DropDownDecoratorProps(
+                dropdownSearchDecoration:
+                InputDecoration(labelText: '2nd Sampler (Optional)')),
+          ),
+          const SizedBox(height: 16),
+          Row(
+            children: [
+              Expanded(
+                  child: TextFormField(
+                      controller: _dateController,
+                      readOnly: true,
+                      decoration: const InputDecoration(labelText: 'Date'))),
+              const SizedBox(width: 16),
+              Expanded(
+                  child: TextFormField(
+                      controller: _timeController,
+                      readOnly: true,
+                      decoration: const InputDecoration(labelText: 'Time'))),
+            ],
+          ),
+          const SizedBox(height: 16),
+          // Sampling Type is fixed for Investigative
+
+          // --- Sample ID ---
+          TextFormField(
+            controller: _barcodeController,
+            decoration: InputDecoration(
+              labelText: 'Sample ID Code *',
+              suffixIcon: IconButton(
+                icon: const Icon(Icons.qr_code_scanner),
+                onPressed: _scanBarcode,
+              ),
+            ),
+            validator: (val) =>
+            val == null || val.isEmpty ? "Sample ID is required" : null,
+            onSaved: (val) => widget.data.sampleIdCode = val,
+            onChanged: (val) => widget.data.sampleIdCode = val, // Update model immediately
+          ),
+          const SizedBox(height: 24),
+
+          // --- NEW: Station Type Selection ---
+          DropdownButtonFormField<String>(
+            value: widget.data.stationTypeSelection,
+            items: _stationTypes
+                .map((type) => DropdownMenuItem(value: type, child: Text(type)))
+                .toList(),
+            onChanged: (value) {
+              setState(() {
+                widget.data.stationTypeSelection = value;
+                _clearStationSelections();
+                _clearNewLocationFields();
+                // If selecting New Location, prepopulate station coords with current if available
+                if (value == 'New Location' && widget.data.currentLatitude != null) {
+                  widget.data.stationLatitude = widget.data.currentLatitude;
+                  widget.data.stationLongitude = widget.data.currentLongitude;
+                  _stationLatController.text = widget.data.stationLatitude!;
+                  _stationLonController.text = widget.data.stationLongitude!;
+                }
+                _calculateDistance(); // Recalculate distance
+              });
+            },
+            decoration: const InputDecoration(labelText: 'Station Type *'),
+            validator: (value) => value == null ? 'Please select station type' : null,
+          ),
+          const SizedBox(height: 16),
+
+          // --- Conditional Station/Location Inputs ---
+
+          // == Existing Manual Station ==
+          if (widget.data.stationTypeSelection == 'Existing Manual Station') ...[
+            DropdownSearch<String>(
+              items: _statesList,
+              selectedItem: widget.data.selectedStateName,
+              popupProps: const PopupProps.menu(
+                  showSearchBox: true,
+                  searchFieldProps: TextFieldProps(
+                      decoration: InputDecoration(hintText: "Search State..."))),
+              dropdownDecoratorProps: const DropDownDecoratorProps(
+                  dropdownSearchDecoration:
+                  InputDecoration(labelText: "Select State *")),
+              onChanged: (state) {
+                setState(() {
+                  widget.data.selectedStateName = state;
+                  _clearStationSelections(); // Clear selections when state changes
+                  _loadStationsForSelectedState();
+                  _calculateDistance();
+                });
+              },
+              validator: (val) => val == null ? "State is required" : null,
+            ),
+            const SizedBox(height: 16),
+            DropdownSearch<Map<String, dynamic>>(
+              items: _manualStationsForState,
+              selectedItem: widget.data.selectedStation,
+              enabled: widget.data.selectedStateName != null,
+              itemAsString: (station) =>
+              "${station['sampling_station_code']} | ${station['sampling_river']} | ${station['sampling_basin']}",
+              popupProps: const PopupProps.menu(
+                  showSearchBox: true,
+                  searchFieldProps: TextFieldProps(
+                      decoration:
+                      InputDecoration(hintText: "Search Station..."))),
+              dropdownDecoratorProps: const DropDownDecoratorProps(
+                  dropdownSearchDecoration:
+                  InputDecoration(labelText: "Select Manual Station *")),
+              onChanged: (station) {
+                if (station != null) {
+                  _updateFormWithSelectedManualStation(station);
+                }
+              },
+              validator: (val) => widget.data.selectedStateName != null && val == null
+                  ? "Manual Station is required"
+                  : null,
+            ),
+            const SizedBox(height: 16),
+            ElevatedButton.icon(
+              icon: const Icon(Icons.explore_outlined),
+              label: const Text("NEARBY MANUAL STATION"),
+              onPressed: _isLoadingLocation ? null : _findAndShowNearbyStations,
+              style: ElevatedButton.styleFrom(
+                padding: const EdgeInsets.symmetric(vertical: 12),
+              ),
+            ),
+          ],
+
+          // == Existing Triennial Station ==
+          if (widget.data.stationTypeSelection == 'Existing Triennial Station') ...[
+            DropdownSearch<String>( // State selection might be needed if not pre-selected
+              items: _statesList,
+              selectedItem: widget.data.selectedStateName,
+              popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search State..."))),
+              dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: "Select State *")),
+              onChanged: (state) {
+                setState(() {
+                  widget.data.selectedStateName = state;
+                  _clearStationSelections();
+                  _loadStationsForSelectedState(); // Reloads both manual and triennial lists
+                  _calculateDistance();
+                });
+              },
+              validator: (val) => val == null ? "State is required" : null,
+            ),
+            const SizedBox(height: 16),
+            DropdownSearch<Map<String, dynamic>>(
+              items: _triennialStationsForState,
+              selectedItem: widget.data.selectedTriennialStation,
+              enabled: widget.data.selectedStateName != null,
+              itemAsString: (station) =>
+              "${station['triennial_station_code']} | ${station['triennial_river']} | ${station['triennial_basin']}", // Use triennial keys
+              popupProps: const PopupProps.menu(
+                  showSearchBox: true,
+                  searchFieldProps: TextFieldProps(
+                      decoration:
+                      InputDecoration(hintText: "Search Station..."))),
+              dropdownDecoratorProps: const DropDownDecoratorProps(
+                  dropdownSearchDecoration:
+                  InputDecoration(labelText: "Select Triennial Station *")),
+              onChanged: (station) {
+                if (station != null) {
+                  _updateFormWithSelectedTriennialStation(station);
+                }
+              },
+              validator: (val) => widget.data.selectedStateName != null && val == null
+                  ? "Triennial Station is required"
+                  : null,
+            ),
+          ],
+
+          // == New Location ==
+          if (widget.data.stationTypeSelection == 'New Location') ...[
+            DropdownSearch<String>( // Use Dropdown for State consistency
+              items: _statesList,
+              selectedItem: widget.data.newStateName,
+              popupProps: const PopupProps.menu(showSearchBox: true, searchFieldProps: TextFieldProps(decoration: InputDecoration(hintText: "Search State..."))),
+              dropdownDecoratorProps: const DropDownDecoratorProps(dropdownSearchDecoration: InputDecoration(labelText: "Select State *")),
+              onChanged: (state) {
+                setState(() {
+                  widget.data.newStateName = state;
+                  widget.data.selectedStateName = state; // Keep consistent if needed elsewhere
+                });
+              },
+              validator: (val) => val == null ? "State is required" : null,
+              onSaved: (val) => widget.data.newStateName = val,
+            ),
+            const SizedBox(height: 16),
+            TextFormField(
+              controller: _newBasinController,
+              decoration: const InputDecoration(labelText: 'Basin Name *'),
+              validator: (val) =>
+              val == null || val.isEmpty ? "Basin name is required" : null,
+              onSaved: (val) => widget.data.newBasinName = val,
+              onChanged: (val) => widget.data.newBasinName = val,
+            ),
+            const SizedBox(height: 16),
+            TextFormField(
+              controller: _newRiverController,
+              decoration: const InputDecoration(labelText: 'River Name *'),
+              validator: (val) =>
+              val == null || val.isEmpty ? "River name is required" : null,
+              onSaved: (val) => widget.data.newRiverName = val,
+              onChanged: (val) => widget.data.newRiverName = val,
+            ),
+            const SizedBox(height: 16),
+            TextFormField( // Optional Station Code for New Location
+              controller: _newStationCodeController,
+              decoration: const InputDecoration(labelText: 'Station Code (Optional)'),
+              onSaved: (val) => widget.data.newStationCode = val,
+              onChanged: (val) => widget.data.newStationCode = val,
+            ),
+          ],
+          const SizedBox(height: 16),
+
+          // --- Station Coordinates (Read-only for existing, editable/GPS-fed for new) ---
+          TextFormField(
+            controller: _stationLatController,
+            readOnly: !isNewLocation, // Editable only for New Location
+            decoration: InputDecoration(
+                labelText: 'Station Latitude ${isNewLocation ? "*" : ""}',
+                hintText: isNewLocation ? 'Use GPS or enter manually' : null
+            ),
+            keyboardType: TextInputType.numberWithOptions(decimal: true),
+            validator: (val) => isNewLocation && (val == null || val.isEmpty) ? "Latitude is required for new location" : null,
+            onChanged: (val) { // Allow manual edit for New Location
+              if (isNewLocation) {
+                widget.data.stationLatitude = val;
+                _calculateDistance(); // Recalculate if manually changed
+              }
+            },
+            onSaved: (val) => widget.data.stationLatitude = val,
+          ),
+          const SizedBox(height: 16),
+          TextFormField(
+            controller: _stationLonController,
+            readOnly: !isNewLocation, // Editable only for New Location
+            decoration: InputDecoration(
+                labelText: 'Station Longitude ${isNewLocation ? "*" : ""}',
+                hintText: isNewLocation ? 'Use GPS or enter manually' : null
+            ),
+            keyboardType: TextInputType.numberWithOptions(decimal: true),
+            validator: (val) => isNewLocation && (val == null || val.isEmpty) ? "Longitude is required for new location" : null,
+            onChanged: (val) { // Allow manual edit for New Location
+              if (isNewLocation) {
+                widget.data.stationLongitude = val;
+                _calculateDistance(); // Recalculate if manually changed
+              }
+            },
+            onSaved: (val) => widget.data.stationLongitude = val,
+          ),
+
+          const SizedBox(height: 24),
+
+          // --- Location Verification ---
+          Text("Location Verification",
+              style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 16),
+          TextFormField(
+              controller: _currentLatController,
+              readOnly: true,
+              decoration: const InputDecoration(labelText: 'Current Latitude')),
+          const SizedBox(height: 16),
+          TextFormField(
+              controller: _currentLonController,
+              readOnly: true,
+              decoration: const InputDecoration(labelText: 'Current Longitude')),
+          if (widget.data.distanceDifferenceInKm != null && widget.data.stationTypeSelection != 'New Location') // Only show distance if NOT new location
+            Padding(
+              padding: const EdgeInsets.only(top: 16.0),
+              child: Container(
+                padding: const EdgeInsets.all(12),
+                decoration: BoxDecoration(
+                  color: ((widget.data.distanceDifferenceInKm ?? 0) * 1000) > 50
+                      ? Colors.red.withOpacity(0.1)
+                      : Colors.green.withOpacity(0.1),
+                  borderRadius: BorderRadius.circular(8),
+                  border: Border.all(
+                      color: ((widget.data.distanceDifferenceInKm ?? 0) * 1000) > 50
+                          ? Colors.red
+                          : Colors.green),
+                ),
+                child: RichText(
+                  textAlign: TextAlign.center,
+                  text: TextSpan(
+                    style: Theme.of(context).textTheme.bodyLarge,
+                    children: <TextSpan>[
+                      const TextSpan(text: 'Distance from Station: '),
+                      TextSpan(
+                        text:
+                        '${(widget.data.distanceDifferenceInKm! * 1000).toStringAsFixed(0)} meters',
+                        style: TextStyle(
+                            fontWeight: FontWeight.bold,
+                            color: ((widget.data.distanceDifferenceInKm ?? 0) * 1000) > 50
+                                ? Colors.red
+                                : Colors.green),
+                      ),
+                    ],
+                  ),
+                ),
+              ),
+            ),
+          const SizedBox(height: 16),
+          OutlinedButton.icon(
+            onPressed: _isLoadingLocation ? null : _getCurrentLocation,
+            icon: _isLoadingLocation
+                ? const SizedBox(
+                width: 20,
+                height: 20,
+                child: CircularProgressIndicator(strokeWidth: 2))
+                : const Icon(Icons.location_searching),
+            label: Text(isNewLocation ? "Get Current Location (for Station & Verification)" : "Get Current Location"),
+          ),
+          const SizedBox(height: 32),
+
+          // --- Navigation ---
+          ElevatedButton(
+            onPressed: _goToNextStep,
+            style: ElevatedButton.styleFrom(
+                padding: const EdgeInsets.symmetric(vertical: 16)),
+            child: const Text('Next'),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+
+// Re-use the same dialog as River Manual In-Situ for nearby stations
+class _NearbyStationsDialog extends StatelessWidget {
+  final List<Map<String, dynamic>> nearbyStations;
+
+  const _NearbyStationsDialog({required this.nearbyStations});
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      title: const Text('Nearby Manual Stations (within 3km)'),
+      content: SizedBox(
+        width: double.maxFinite,
+        child: nearbyStations.isEmpty
+            ? const Center(child: Text('No stations found.'))
+            : ListView.builder(
+          shrinkWrap: true,
+          itemCount: nearbyStations.length,
+          itemBuilder: (context, index) {
+            final item = nearbyStations[index];
+            final station = item['station'] as Map<String, dynamic>;
+            final distanceInMeters = (item['distance'] as double) * 1000;
+
+            return Card(
+              child: ListTile(
+                title: Text("${station['sampling_station_code'] ?? 'N/A'}"),
+                subtitle: Text("${station['sampling_river'] ?? 'N/A'}"),
+                trailing: Text("${distanceInMeters.toStringAsFixed(0)} m"),
+                onTap: () {
+                  Navigator.of(context).pop(station); // Return the selected station map
+                },
+              ),
+            );
+          },
+        ),
+      ),
+      actions: [
+        TextButton(
+          onPressed: () => Navigator.of(context).pop(),
+          child: const Text('Cancel'),
+        ),
+      ],
+    );
+  }
+}

lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_2_site_info.dart

@@ -0,0 +1,231 @@
+// lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_2_site_info.dart
+
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:image_picker/image_picker.dart';
+import 'package:provider/provider.dart';
+
+import '../../../../models/river_inves_manual_sampling_data.dart'; // Updated model
+import '../../../../services/river_investigative_sampling_service.dart'; // Updated service
+
+class RiverInvesStep2SiteInfo extends StatefulWidget {
+  final RiverInvesManualSamplingData data;
+  final VoidCallback onNext;
+
+  const RiverInvesStep2SiteInfo({
+    super.key,
+    required this.data,
+    required this.onNext,
+  });
+
+  @override
+  State<RiverInvesStep2SiteInfo> createState() =>
+      _RiverInvesStep2SiteInfoState();
+}
+
+class _RiverInvesStep2SiteInfoState extends State<RiverInvesStep2SiteInfo> {
+  final _formKey = GlobalKey<FormState>();
+  bool _isPickingImage = false;
+
+  late final TextEditingController _eventRemarksController;
+  late final TextEditingController _labRemarksController;
+  final List<String> _weatherOptions = [
+    'Cloudy',
+    'Drizzle',
+    'Rainy',
+    'Sunny',
+    'Windy'
+  ];
+
+  @override
+  void initState() {
+    super.initState();
+    _eventRemarksController = TextEditingController(text: widget.data.eventRemarks);
+    _labRemarksController = TextEditingController(text: widget.data.labRemarks);
+  }
+
+  @override
+  void dispose() {
+    _eventRemarksController.dispose();
+    _labRemarksController.dispose();
+    super.dispose();
+  }
+
+  void _setImage(Function(File?) setImageCallback, ImageSource source,
+      String imageInfo, {required bool isRequired}) async {
+    if (_isPickingImage) return;
+    setState(() => _isPickingImage = true);
+
+    final service = Provider.of<RiverInvestigativeSamplingService>(context, listen: false);
+
+    // --- MODIFICATION: Get station code based on selection ---
+    final String? stationCode = widget.data.getDeterminedStationCode();
+    // --- END MODIFICATION ---
+
+    final file = await service.pickAndProcessImage( // Call the service's method
+      source,
+      data: widget.data, // Pass the investigative data model
+      imageInfo: imageInfo,
+      isRequired: isRequired,
+      stationCode: stationCode, // Pass the determined station code
+    );
+
+    if (file != null) {
+      setState(() => setImageCallback(file));
+    } else if (mounted) {
+      _showSnackBar(
+          'Image selection failed. Please ensure all photos are taken in landscape mode.',
+          isError: true);
+    }
+
+    if (mounted) {
+      setState(() => _isPickingImage = false);
+    }
+  }
+
+  void _goToNextStep() {
+    if (!_formKey.currentState!.validate()) {
+      return;
+    }
+
+    _formKey.currentState!.save();
+
+    if (widget.data.backgroundStationImage == null ||
+        widget.data.upstreamRiverImage == null ||
+        widget.data.downstreamRiverImage == null) {
+      _showSnackBar('Please attach all 3 required photos before proceeding.',
+          isError: true);
+      return;
+    }
+
+    widget.onNext();
+  }
+
+  void _showSnackBar(String message, {bool isError = false}) {
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+        content: Text(message),
+        backgroundColor: isError ? Colors.red : null,
+      ));
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Form(
+      key: _formKey,
+      child: ListView(
+        padding: const EdgeInsets.all(24.0),
+        children: [
+          Text("On-Site Information",
+              style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 16),
+          DropdownButtonFormField<String>(
+            value: widget.data.weather,
+            items: _weatherOptions
+                .map((item) => DropdownMenuItem(value: item, child: Text(item)))
+                .toList(),
+            onChanged: (value) => setState(() => widget.data.weather = value),
+            decoration: const InputDecoration(labelText: 'Weather *'),
+            validator: (value) => value == null ? 'Weather is required' : null,
+            onSaved: (value) => widget.data.weather = value,
+          ),
+          const SizedBox(height: 16),
+          TextFormField(
+            controller: _eventRemarksController,
+            decoration: const InputDecoration(
+                labelText: 'Event Remarks (Optional)',
+                hintText: 'e.g., unusual smells, colors, etc.'),
+            onSaved: (value) => widget.data.eventRemarks = value,
+            maxLines: 3,
+          ),
+          const SizedBox(height: 16),
+          TextFormField(
+            controller: _labRemarksController,
+            decoration: const InputDecoration(labelText: 'Lab Remarks (Optional)'),
+            onSaved: (value) => widget.data.labRemarks = value,
+            maxLines: 3,
+          ),
+          const Divider(height: 32),
+          Text("Required Photos *",
+              style: Theme.of(context).textTheme.titleLarge),
+          const Text("All photos must be taken in landscape (horizontal) orientation.",
+              style: TextStyle(color: Colors.grey)),
+          const SizedBox(height: 8),
+          _buildImagePicker(
+              'Background Station',
+              'BACKGROUND_STATION',
+              widget.data.backgroundStationImage,
+                  (file) => widget.data.backgroundStationImage = file,
+              isRequired: true),
+          _buildImagePicker('Upstream River', 'UPSTREAM_RIVER',
+              widget.data.upstreamRiverImage, (file) => widget.data.upstreamRiverImage = file,
+              isRequired: true),
+          _buildImagePicker(
+              'Downstream River',
+              'DOWNSTREAM_RIVER',
+              widget.data.downstreamRiverImage,
+                  (file) => widget.data.downstreamRiverImage = file,
+              isRequired: true),
+          const SizedBox(height: 24),
+          ElevatedButton(
+            onPressed: _goToNextStep,
+            style: ElevatedButton.styleFrom(
+                padding: const EdgeInsets.symmetric(vertical: 16)),
+            child: const Text('Next'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  // _buildImagePicker remains the same as in RiverInSituStep2SiteInfo
+  Widget _buildImagePicker(String title, String imageInfo, File? imageFile, Function(File?) setImageCallback, {TextEditingController? remarkController, bool isRequired = false}) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 8.0),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(title + (isRequired ? ' *' : ''), style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w500)),
+          const SizedBox(height: 8),
+          if (imageFile != null)
+            Stack(
+              alignment: Alignment.topRight,
+              children: [
+                ClipRRect(borderRadius: BorderRadius.circular(8.0), child: Image.file(imageFile, key: UniqueKey(), height: 150, width: double.infinity, fit: BoxFit.cover)),
+                Container(
+                  margin: const EdgeInsets.all(4),
+                  decoration: BoxDecoration(color: Colors.black.withOpacity(0.6), shape: BoxShape.circle),
+                  child: IconButton(
+                    visualDensity: VisualDensity.compact,
+                    icon: const Icon(Icons.close, color: Colors.white, size: 20),
+                    onPressed: () => setState(() => setImageCallback(null)),
+                  ),
+                ),
+              ],
+            )
+          else
+            Row(
+              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+              children: [
+                ElevatedButton.icon(onPressed: _isPickingImage ? null : () => _setImage(setImageCallback, ImageSource.camera, imageInfo, isRequired: isRequired), icon: const Icon(Icons.camera_alt), label: const Text("Camera")),
+                ElevatedButton.icon(onPressed: _isPickingImage ? null : () => _setImage(setImageCallback, ImageSource.gallery, imageInfo, isRequired: isRequired), icon: const Icon(Icons.photo_library), label: const Text("Gallery")),
+              ],
+            ),
+          if (remarkController != null)
+            Padding(
+              padding: const EdgeInsets.only(top: 8.0),
+              child: TextFormField(
+                controller: remarkController,
+                decoration: InputDecoration(
+                  labelText: 'Remarks for $title',
+                  hintText: 'Add an optional remark...',
+                  border: const OutlineInputBorder(),
+                ),
+              ),
+            ),
+        ],
+      ),
+    );
+  }
+}

lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_4_additional_info.dart

@@ -0,0 +1,216 @@
+// lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_4_additional_info.dart
+
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:image_picker/image_picker.dart';
+import 'package:provider/provider.dart';
+
+import '../../../../models/river_inves_manual_sampling_data.dart'; // Updated model
+import '../../../../services/river_investigative_sampling_service.dart'; // Updated service
+
+class RiverInvesStep4AdditionalInfo extends StatefulWidget {
+  final RiverInvesManualSamplingData data;
+  final VoidCallback onNext;
+
+  const RiverInvesStep4AdditionalInfo({
+    super.key,
+    required this.data,
+    required this.onNext,
+  });
+
+  @override
+  State<RiverInvesStep4AdditionalInfo> createState() =>
+      _RiverInvesStep4AdditionalInfoState();
+}
+
+class _RiverInvesStep4AdditionalInfoState
+    extends State<RiverInvesStep4AdditionalInfo> {
+  final _formKey = GlobalKey<FormState>();
+  bool _isPickingImage = false;
+
+  late final TextEditingController _optionalRemark1Controller;
+  late final TextEditingController _optionalRemark2Controller;
+  late final TextEditingController _optionalRemark3Controller;
+  late final TextEditingController _optionalRemark4Controller;
+
+  @override
+  void initState() {
+    super.initState();
+    _optionalRemark1Controller = TextEditingController(text: widget.data.optionalRemark1);
+    _optionalRemark2Controller = TextEditingController(text: widget.data.optionalRemark2);
+    _optionalRemark3Controller = TextEditingController(text: widget.data.optionalRemark3);
+    _optionalRemark4Controller = TextEditingController(text: widget.data.optionalRemark4);
+  }
+
+  @override
+  void dispose() {
+    _optionalRemark1Controller.dispose();
+    _optionalRemark2Controller.dispose();
+    _optionalRemark3Controller.dispose();
+    _optionalRemark4Controller.dispose();
+    super.dispose();
+  }
+
+  void _setImage(Function(File?) setImageCallback, ImageSource source,
+      String imageInfo, {required bool isRequired}) async {
+    if (_isPickingImage) return;
+    setState(() => _isPickingImage = true);
+
+    final service = Provider.of<RiverInvestigativeSamplingService>(context, listen: false);
+
+    // --- MODIFICATION: Get station code based on selection ---
+    final String? stationCode = widget.data.getDeterminedStationCode();
+    // --- END MODIFICATION ---
+
+    final file = await service.pickAndProcessImage( // Call the service's method
+      source,
+      data: widget.data, // Pass investigative data
+      imageInfo: imageInfo,
+      isRequired: isRequired,
+      stationCode: stationCode, // Pass determined code
+    );
+
+    if (file != null) {
+      setState(() => setImageCallback(file));
+    } else if (mounted) {
+      _showSnackBar(
+          'Image selection failed. Please ensure all photos are taken in landscape mode.',
+          isError: true);
+    }
+
+    if (mounted) {
+      setState(() => _isPickingImage = false);
+    }
+  }
+
+  void _goToNextStep() {
+    // Save remarks explicitly before validating/proceeding
+    widget.data.optionalRemark1 = _optionalRemark1Controller.text.trim();
+    widget.data.optionalRemark2 = _optionalRemark2Controller.text.trim();
+    widget.data.optionalRemark3 = _optionalRemark3Controller.text.trim();
+    widget.data.optionalRemark4 = _optionalRemark4Controller.text.trim();
+
+    if (_formKey.currentState!.validate()) { // Validation (if any) is done here
+      _formKey.currentState!.save(); // Save form fields (if any)
+
+      if (widget.data.sampleTurbidityImage == null) {
+        _showSnackBar(
+            'Please attach the Sample Turbidity photo before proceeding.',
+            isError: true);
+        return;
+      }
+      widget.onNext();
+    }
+  }
+
+  void _showSnackBar(String message, {bool isError = false}) {
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+        content: Text(message),
+        backgroundColor: isError ? Colors.red : null,
+      ));
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Form(
+      key: _formKey, // Needed if you add any validating FormFields later
+      child: ListView(
+        padding: const EdgeInsets.all(24.0),
+        children: [
+          Text("Additional Photos",
+              style: Theme.of(context).textTheme.headlineSmall),
+          const SizedBox(height: 24),
+          Text("Required Photo *",
+              style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 8),
+          _buildImagePicker(
+              'Sample Turbidity',
+              'SAMPLE_TURBIDITY',
+              widget.data.sampleTurbidityImage,
+                  (file) => widget.data.sampleTurbidityImage = file,
+              isRequired: true),
+          const Divider(height: 32),
+          Text("Optional Photos & Remarks",
+              style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 8),
+          _buildImagePicker('Optional Photo 1', 'OPTIONAL_1',
+              widget.data.optionalImage1, (file) => widget.data.optionalImage1 = file,
+              remarkController: _optionalRemark1Controller, isRequired: false),
+          _buildImagePicker('Optional Photo 2', 'OPTIONAL_2',
+              widget.data.optionalImage2, (file) => widget.data.optionalImage2 = file,
+              remarkController: _optionalRemark2Controller, isRequired: false),
+          _buildImagePicker('Optional Photo 3', 'OPTIONAL_3',
+              widget.data.optionalImage3, (file) => widget.data.optionalImage3 = file,
+              remarkController: _optionalRemark3Controller, isRequired: false),
+          _buildImagePicker('Optional Photo 4', 'OPTIONAL_4',
+              widget.data.optionalImage4, (file) => widget.data.optionalImage4 = file,
+              remarkController: _optionalRemark4Controller, isRequired: false),
+          const SizedBox(height: 24),
+          ElevatedButton(
+            onPressed: _goToNextStep,
+            style: ElevatedButton.styleFrom(
+                padding: const EdgeInsets.symmetric(vertical: 16)),
+            child: const Text('Next'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  // _buildImagePicker remains the same as in RiverInSituStep4AdditionalInfo
+  Widget _buildImagePicker(String title, String imageInfo, File? imageFile, Function(File?) setImageCallback, {TextEditingController? remarkController, bool isRequired = false}) {
+    // Copied from RiverInSituStep4AdditionalInfoState._buildImagePicker
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 8.0),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(title + (isRequired ? ' *' : ''), style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w500)),
+          const SizedBox(height: 8),
+          if (imageFile != null)
+            Stack(
+              alignment: Alignment.topRight,
+              children: [
+                ClipRRect(borderRadius: BorderRadius.circular(8.0), child: Image.file(imageFile, key: UniqueKey(), height: 150, width: double.infinity, fit: BoxFit.cover)),
+                Container(
+                  margin: const EdgeInsets.all(4),
+                  decoration: BoxDecoration(color: Colors.black.withOpacity(0.6), shape: BoxShape.circle),
+                  child: IconButton(
+                    visualDensity: VisualDensity.compact,
+                    icon: const Icon(Icons.close, color: Colors.white, size: 20),
+                    onPressed: () => setState(() => setImageCallback(null)), // Clear the image file in the data model
+                  ),
+                ),
+              ],
+            )
+          else
+            Row(
+              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+              children: [
+                // Use the _setImage method defined in this state class
+                ElevatedButton.icon(onPressed: _isPickingImage ? null : () => _setImage(setImageCallback, ImageSource.camera, imageInfo, isRequired: isRequired), icon: const Icon(Icons.camera_alt), label: const Text("Camera")),
+                ElevatedButton.icon(onPressed: _isPickingImage ? null : () => _setImage(setImageCallback, ImageSource.gallery, imageInfo, isRequired: isRequired), icon: const Icon(Icons.photo_library), label: const Text("Gallery")),
+              ],
+            ),
+          // Remarks field, linked via the passed controller
+          if (remarkController != null)
+            Padding(
+              padding: const EdgeInsets.only(top: 8.0),
+              child: TextFormField(
+                controller: remarkController,
+                decoration: InputDecoration(
+                  labelText: 'Remarks for $title',
+                  hintText: 'Add an optional remark...',
+                  border: const OutlineInputBorder(),
+                ),
+                // No validator needed for optional remarks
+                // onSaved handled externally by _goToNextStep reading controllers
+              ),
+            ),
+        ],
+      ),
+    );
+  }
+}

lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_5_summary.dart

@@ -0,0 +1,371 @@
+// lib/screens/river/investigative/manual_sampling/river_inves_in_situ_step_5_summary.dart
+
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import '../../../../auth_provider.dart';
+import '../../../../models/river_inves_manual_sampling_data.dart'; // Use Investigative model
+
+class RiverInvesStep5Summary extends StatelessWidget { // Renamed class
+  final RiverInvesManualSamplingData data; // Use Investigative data model
+  final VoidCallback onSubmit;
+  final bool isLoading;
+
+  const RiverInvesStep5Summary({ // Renamed constructor
+    super.key,
+    required this.data,
+    required this.onSubmit,
+    required this.isLoading,
+  });
+
+  // Parameter validation logic remains the same as it uses river limits
+  // Maps the app's internal parameter keys to the names used in the database.
+  static const Map<String, String> _parameterKeyToLimitName = {
+    'oxygenConcentration': 'Oxygen Conc',
+    'oxygenSaturation': 'Oxygen Sat',
+    'ph': 'pH',
+    'salinity': 'Salinity',
+    'electricalConductivity': 'Conductivity',
+    'temperature': 'Temperature',
+    'tds': 'TDS',
+    'turbidity': 'Turbidity',
+    'ammonia': 'Ammonia',
+    'batteryVoltage': 'Battery',
+  }; //
+
+  /// Re-validates the final parameters against the defined limits.
+  Set<String> _getOutOfBoundsKeys(BuildContext context) {
+    final authProvider = Provider.of<AuthProvider>(context, listen: false);
+    // Use the same river parameter limits as the manual module
+    final riverLimits = authProvider.riverParameterLimits ?? [];
+    final Set<String> invalidKeys = {};
+
+    // Access fields from the RiverInvesManualSamplingData model
+    final readings = {
+      'oxygenConcentration': data.oxygenConcentration, 'oxygenSaturation': data.oxygenSaturation,
+      'ph': data.ph, 'salinity': data.salinity, 'electricalConductivity': data.electricalConductivity,
+      'temperature': data.temperature, 'tds': data.tds, 'turbidity': data.turbidity,
+      'ammonia': data.ammonia, 'batteryVoltage': data.batteryVoltage,
+    }; //
+
+    double? parseLimitValue(dynamic value) {
+      if (value == null) return null;
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    readings.forEach((key, value) {
+      if (value == null || value == -999.0) return; //
+
+      final limitName = _parameterKeyToLimitName[key]; //
+      if (limitName == null) return;
+
+      final limitData = riverLimits.firstWhere((l) => l['param_parameter_list'] == limitName, orElse: () => {}); //
+
+      if (limitData.isNotEmpty) {
+        final lowerLimit = parseLimitValue(limitData['param_lower_limit']);
+        final upperLimit = parseLimitValue(limitData['param_upper_limit']);
+
+        if ((lowerLimit != null && value < lowerLimit) || (upperLimit != null && value > upperLimit)) {
+          invalidKeys.add(key); //
+        }
+      }
+    });
+
+    return invalidKeys;
+  }
+  // --- END: Parameter Validation Logic ---
+
+  @override
+  Widget build(BuildContext context) {
+    // Get the set of out-of-bounds keys before building the list.
+    final outOfBoundsKeys = _getOutOfBoundsKeys(context); //
+
+    return ListView(
+      padding: const EdgeInsets.all(16.0),
+      children: [
+        Text(
+          "Please review all information before submitting.",
+          style: Theme.of(context).textTheme.titleMedium,
+          textAlign: TextAlign.center,
+        ),
+        const SizedBox(height: 16),
+
+        _buildSectionCard(
+          context,
+          "Sampling & Station Details",
+          [
+            _buildDetailRow("1st Sampler:", data.firstSamplerName), //
+            _buildDetailRow("2nd Sampler:", data.secondSampler?['first_name']?.toString()), //
+            _buildDetailRow("Sampling Date:", data.samplingDate), //
+            _buildDetailRow("Sampling Time:", data.samplingTime), //
+            _buildDetailRow("Sampling Type:", data.samplingType), // Should display "Investigative"
+            _buildDetailRow("Sample ID Code:", data.sampleIdCode), //
+            const Divider(height: 20),
+            // --- MODIFICATION: Display station/location based on type ---
+            _buildDetailRow("Station Type:", data.stationTypeSelection), //
+            if (data.stationTypeSelection == 'Existing Manual Station') ...[
+              _buildDetailRow("State:", data.selectedStateName), //
+              _buildDetailRow(
+                  "Manual Station:",
+                  "${data.selectedStation?['sampling_station_code']} | ${data.selectedStation?['sampling_river']} | ${data.selectedStation?['sampling_basin']}"
+              ), //
+            ] else if (data.stationTypeSelection == 'Existing Triennial Station') ...[
+              _buildDetailRow("State:", data.selectedStateName), //
+              _buildDetailRow(
+                  "Triennial Station:",
+                  "${data.selectedTriennialStation?['triennial_station_code']} | ${data.selectedTriennialStation?['triennial_river']} | ${data.selectedTriennialStation?['triennial_basin']}"
+              ), // (Using assumed keys from model)
+            ] else if (data.stationTypeSelection == 'New Location') ...[
+              _buildDetailRow("New Location State:", data.newStateName), //
+              _buildDetailRow("New Location Basin:", data.newBasinName), //
+              _buildDetailRow("New Location River:", data.newRiverName), //
+              _buildDetailRow("New Location Code:", data.newStationCode), // Optional
+            ],
+            _buildDetailRow("Determined Station Location:", "${data.stationLatitude}, ${data.stationLongitude}"), // Lat/Lon determined in Step 1
+            // --- END MODIFICATION ---
+          ],
+        ),
+
+        _buildSectionCard(
+          context,
+          "Site Info & Required Photos",
+          [
+            _buildDetailRow("Current Location:", "${data.currentLatitude}, ${data.currentLongitude}"), //
+            // Only show distance if it's not a new location
+            if (data.stationTypeSelection != 'New Location')
+              _buildDetailRow("Distance Difference:", data.distanceDifferenceInKm != null ? "${(data.distanceDifferenceInKm! * 1000).toStringAsFixed(0)} meters" : "N/A"), //
+            // Only show distance remarks if not a new location
+            if (data.stationTypeSelection != 'New Location' && data.distanceDifferenceRemarks != null && data.distanceDifferenceRemarks!.isNotEmpty)
+              _buildDetailRow("Distance Remarks:", data.distanceDifferenceRemarks), //
+            const Divider(height: 20),
+
+            _buildDetailRow("Weather:", data.weather), //
+            _buildDetailRow("Event Remarks:", data.eventRemarks), //
+            _buildDetailRow("Lab Remarks:", data.labRemarks), //
+            const Divider(height: 20),
+
+            _buildImageCard("Background Station", data.backgroundStationImage), //
+            _buildImageCard("Upstream River", data.upstreamRiverImage), //
+            _buildImageCard("Downstream River", data.downstreamRiverImage), //
+          ],
+        ),
+
+        _buildSectionCard(
+          context,
+          "Additional Photos & Remarks",
+          [
+            _buildImageCard("Sample Turbidity", data.sampleTurbidityImage), //
+            const Divider(height: 24),
+            Text("Optional Photos", style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold)),
+            const SizedBox(height: 8),
+            _buildImageCard("Optional Photo 1", data.optionalImage1, remark: data.optionalRemark1), //
+            _buildImageCard("Optional Photo 2", data.optionalImage2, remark: data.optionalRemark2), //
+            _buildImageCard("Optional Photo 3", data.optionalImage3, remark: data.optionalRemark3), //
+            _buildImageCard("Optional Photo 4", data.optionalImage4, remark: data.optionalRemark4), //
+          ],
+        ),
+
+        _buildSectionCard(
+          context,
+          "Captured Parameters",
+          [
+            _buildDetailRow("Sonde ID:", data.sondeId), //
+            _buildDetailRow("Capture Time:", "${data.dataCaptureDate} ${data.dataCaptureTime}"), //
+            const Divider(height: 20),
+            // Parameter list remains the same, uses the same helper and outOfBoundsKeys
+            _buildParameterListItem(context, icon: Icons.air, label: "Oxygen Conc.", unit: "mg/L", value: data.oxygenConcentration, isOutOfBounds: outOfBoundsKeys.contains('oxygenConcentration')),
+            _buildParameterListItem(context, icon: Icons.percent, label: "Oxygen Sat.", unit: "%", value: data.oxygenSaturation, isOutOfBounds: outOfBoundsKeys.contains('oxygenSaturation')),
+            _buildParameterListItem(context, icon: Icons.science_outlined, label: "pH", unit: "", value: data.ph, isOutOfBounds: outOfBoundsKeys.contains('ph')),
+            _buildParameterListItem(context, icon: Icons.waves, label: "Salinity", unit: "ppt", value: data.salinity, isOutOfBounds: outOfBoundsKeys.contains('salinity')),
+            _buildParameterListItem(context, icon: Icons.flash_on, label: "Conductivity", unit: "µS/cm", value: data.electricalConductivity, isOutOfBounds: outOfBoundsKeys.contains('electricalConductivity')),
+            _buildParameterListItem(context, icon: Icons.thermostat, label: "Temperature", unit: "°C", value: data.temperature, isOutOfBounds: outOfBoundsKeys.contains('temperature')),
+            _buildParameterListItem(context, icon: Icons.grain, label: "TDS", unit: "mg/L", value: data.tds, isOutOfBounds: outOfBoundsKeys.contains('tds')),
+            _buildParameterListItem(context, icon: Icons.opacity, label: "Turbidity", unit: "NTU", value: data.turbidity, isOutOfBounds: outOfBoundsKeys.contains('turbidity')),
+            _buildParameterListItem(context, icon: Icons.science, label: "Ammonia", unit: "mg/L", value: data.ammonia, isOutOfBounds: outOfBoundsKeys.contains('ammonia')),
+            _buildParameterListItem(context, icon: Icons.battery_charging_full, label: "Battery", unit: "V", value: data.batteryVoltage, isOutOfBounds: outOfBoundsKeys.contains('batteryVoltage')),
+            const Divider(height: 20),
+            // Flowrate summary remains the same
+            _buildFlowrateSummary(context),
+          ],
+        ),
+
+        const SizedBox(height: 24),
+        isLoading
+            ? const Center(child: CircularProgressIndicator())
+            : ElevatedButton.icon(
+          onPressed: onSubmit,
+          icon: const Icon(Icons.cloud_upload),
+          label: const Text('Confirm & Submit'),
+          style: ElevatedButton.styleFrom(
+            padding: const EdgeInsets.symmetric(vertical: 16),
+            textStyle: const TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
+          ),
+        ),
+        const SizedBox(height: 16),
+      ],
+    );
+  }
+
+  // Helper widgets (_buildSectionCard, _buildDetailRow, _buildParameterListItem,
+  // _buildImageCard, _buildFlowrateSummary) are identical to the ones in
+  // river_in_situ_step_5_summary.dart and are reused here.
+
+  Widget _buildSectionCard(BuildContext context, String title, List<Widget> children) {
+    // Copied from RiverInSituStep5Summary
+    return Card(
+      margin: const EdgeInsets.symmetric(vertical: 8.0),
+      elevation: 2,
+      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(
+              title,
+              style: TextStyle(
+                fontSize: 18,
+                fontWeight: FontWeight.bold,
+                color: Theme.of(context).primaryColor,
+              ),
+            ),
+            const Divider(height: 20, thickness: 1),
+            ...children,
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildDetailRow(String label, String? value) {
+    // Copied from RiverInSituStep5Summary
+    // Handles cleaning up potential 'null' strings from map access
+    String displayValue = value
+        ?.replaceAll('null - null', '')
+        ?.replaceAll('null |', '')
+        ?.replaceAll('| null', '')
+        ?.trim() ?? 'N/A';
+    if (displayValue.isEmpty || displayValue == "-") {
+      displayValue = 'N/A';
+    }
+
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 6.0),
+      child: Row(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Expanded(
+            flex: 2,
+            child: Text(label, style: const TextStyle(fontWeight: FontWeight.bold)),
+          ),
+          const SizedBox(width: 8),
+          Expanded(
+            flex: 3,
+            child: Text(displayValue, style: const TextStyle(fontSize: 16)),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildParameterListItem(BuildContext context, {required IconData icon, required String label, required String unit, required double? value, bool isOutOfBounds = false}) {
+    // Copied from RiverInSituStep5Summary
+    final bool isMissing = value == null || value == -999.0;
+    // Format the value to 5 decimal places if it's a valid number.
+    final String displayValue = isMissing ? 'N/A' : '${value.toStringAsFixed(5)} ${unit}'.trim();
+
+    // Determine the color for the value based on theme and status.
+    final Color? defaultTextColor = Theme.of(context).textTheme.bodyLarge?.color;
+    final Color valueColor = isOutOfBounds
+        ? Colors.red // Out of bounds = Red
+        : (isMissing ? Colors.grey : defaultTextColor ?? Colors.black); // Missing = Grey, else Default
+
+    return ListTile(
+      dense: true,
+      contentPadding: EdgeInsets.zero,
+      leading: Icon(icon, color: Theme.of(context).primaryColor, size: 28),
+      title: Text(label, style: const TextStyle(fontWeight: FontWeight.bold)),
+      trailing: Text(
+        displayValue,
+        style: Theme.of(context).textTheme.bodyLarge?.copyWith(
+          color: valueColor,
+          fontWeight: isOutOfBounds ? FontWeight.bold : null, // Bold if out of bounds
+        ),
+      ),
+    );
+  }
+
+  Widget _buildImageCard(String title, File? image, {String? remark}) {
+    // Copied from RiverInSituStep5Summary
+    final bool hasRemark = remark != null && remark.isNotEmpty;
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 8.0),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(title, style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16)),
+          const SizedBox(height: 8),
+          if (image != null)
+            ClipRRect(
+              borderRadius: BorderRadius.circular(8.0),
+              // Use UniqueKey to force rebuild if image file path is the same but content changed (less likely here)
+              child: Image.file(image, key: UniqueKey(), height: 200, width: double.infinity, fit: BoxFit.cover),
+            )
+          else
+            Container(
+              height: 100,
+              width: double.infinity,
+              decoration: BoxDecoration(
+                  color: Colors.grey[200],
+                  borderRadius: BorderRadius.circular(8.0),
+                  border: Border.all(color: Colors.grey[300]!)),
+              child: const Center(child: Text('No Image Attached', style: TextStyle(color: Colors.grey))),
+            ),
+          if (hasRemark)
+            Padding(
+              padding: const EdgeInsets.only(top: 8.0),
+              child: Text('Remark: $remark', style: const TextStyle(fontStyle: FontStyle.italic)),
+            ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildFlowrateSummary(BuildContext context) {
+    // Copied from RiverInSituStep5Summary
+    final method = data.flowrateMethod ?? 'N/A'; //
+
+    List<Widget> children = [
+      _buildDetailRow("Flowrate Method:", method), //
+    ];
+
+    if (method == 'Surface Drifter') {
+      children.add(
+          Padding(
+            padding: const EdgeInsets.only(left: 16.0, top: 4.0),
+            child: Column(
+              children: [
+                _buildDetailRow("Height:", data.flowrateSurfaceDrifterHeight != null ? "${data.flowrateSurfaceDrifterHeight} m" : "N/A"), //
+                _buildDetailRow("Distance:", data.flowrateSurfaceDrifterDistance != null ? "${data.flowrateSurfaceDrifterDistance} m" : "N/A"), //
+                _buildDetailRow("Time First:", data.flowrateSurfaceDrifterTimeFirst ?? "N/A"), //
+                _buildDetailRow("Time Last:", data.flowrateSurfaceDrifterTimeLast ?? "N/A"), //
+              ],
+            ),
+          )
+      );
+    }
+
+    // Always show the final flowrate value row
+    children.add(
+        _buildDetailRow("Flowrate Value:", data.flowrateValue != null ? '${data.flowrateValue!.toStringAsFixed(4)} m/s' : 'NA') //
+    );
+
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: children,
+    );
+  }
+}

lib/screens/river/investigative/river_investigative_manual_sampling.dart

@@ -0,0 +1,189 @@
+// lib/screens/river/investigative/river_investigative_manual_sampling.dart
+
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:intl/intl.dart'; // For formatting date/time
+
+import '../../../../auth_provider.dart';
+import '../../../../models/river_inves_manual_sampling_data.dart'; // Updated model
+import '../../../../services/river_investigative_sampling_service.dart'; // Updated service
+// Removed CustomStepper import
+
+// Import Step Widgets
+import 'manual_sampling/river_inves_in_situ_step_1_sampling_info.dart';
+import 'manual_sampling/river_inves_in_situ_step_2_site_info.dart';
+import 'manual_sampling/river_inves_in_situ_step_3_data_capture.dart';
+import 'manual_sampling/river_inves_in_situ_step_4_additional_info.dart';
+import 'manual_sampling/river_inves_in_situ_step_5_summary.dart';
+
+class RiverInvestigativeManualSamplingScreen extends StatefulWidget {
+  const RiverInvestigativeManualSamplingScreen({super.key});
+
+  @override
+  State<RiverInvestigativeManualSamplingScreen> createState() =>
+      _RiverInvestigativeManualSamplingScreenState();
+}
+
+class _RiverInvestigativeManualSamplingScreenState
+    extends State<RiverInvestigativeManualSamplingScreen> {
+  int _currentStep = 0;
+  bool _isLoading = false;
+  late RiverInvesManualSamplingData _samplingData;
+
+  @override
+  void initState() {
+    super.initState();
+    _samplingData = RiverInvesManualSamplingData(
+      // Initialize with current date and time if needed, handled in Step 1 init
+    );
+  }
+
+  void _nextStep() {
+    if (_currentStep < 4) {
+      setState(() {
+        _currentStep++;
+      });
+    } else {
+      _submitForm();
+    }
+  }
+
+  void _previousStep() {
+    if (_currentStep > 0) {
+      setState(() {
+        _currentStep--;
+      });
+    } else {
+      Navigator.of(context).pop();
+    }
+  }
+
+  Future<void> _submitForm() async {
+    setState(() {
+      _isLoading = true;
+    });
+
+    final service = Provider.of<RiverInvestigativeSamplingService>(context, listen: false);
+    final auth = Provider.of<AuthProvider>(context, listen: false);
+
+    try {
+      final result = await service.submitData(
+        data: _samplingData,
+        appSettings: auth.appSettings,
+        authProvider: auth,
+        // logDirectory: null, // Let service handle initial log creation
+      );
+
+      _samplingData.submissionStatus = result['status'];
+      _samplingData.submissionMessage = result['message'];
+      _samplingData.reportId = result['reportId'];
+
+      if (mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(
+            content: Text(result['message'] ?? 'Submission processed.'),
+            backgroundColor: result['success'] ? Colors.green : Colors.orange,
+          ),
+        );
+        if (result['success']) {
+          Future.delayed(const Duration(seconds: 2), () {
+            if (mounted) {
+              Navigator.of(context).pop();
+            }
+          });
+        }
+      }
+    } catch (e) {
+      if (mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(
+            content: Text('An unexpected error occurred: $e'),
+            backgroundColor: Colors.red,
+          ),
+        );
+      }
+      _samplingData.submissionStatus = 'Error';
+      _samplingData.submissionMessage = 'An unexpected error occurred: $e';
+    } finally {
+      if (mounted) {
+        setState(() {
+          _isLoading = false;
+        });
+      }
+    }
+  }
+
+  // --- MODIFICATION: Removed _getStepTitle method ---
+
+  @override
+  Widget build(BuildContext context) {
+    return WillPopScope(
+      onWillPop: () async {
+        if (_isLoading) return false;
+        if (_currentStep > 0) {
+          final shouldPop = await showDialog<bool>(
+            context: context,
+            builder: (context) => AlertDialog(
+              title: const Text('Discard Sampling Data?'),
+              content: const Text('Are you sure you want to go back? All unsaved data for this sampling event will be lost.'),
+              actions: [
+                TextButton(
+                  onPressed: () => Navigator.of(context).pop(false),
+                  child: const Text('Cancel'),
+                ),
+                TextButton(
+                  onPressed: () => Navigator.of(context).pop(true),
+                  child: const Text('Discard'),
+                ),
+              ],
+            ),
+          );
+          return shouldPop ?? false;
+        }
+        return true;
+      },
+      child: Scaffold(
+        appBar: AppBar(
+          // --- MODIFICATION: Title is now dynamic to match river manual ---
+          title: Text('In-Situ Sampling (${_currentStep + 1}/5)'),
+          leading: IconButton(
+            icon: const Icon(Icons.arrow_back),
+            onPressed: _isLoading ? null : _previousStep,
+          ),
+          bottom: PreferredSize(
+            preferredSize: const Size.fromHeight(4.0),
+            child: _isLoading ? const LinearProgressIndicator() : const SizedBox.shrink(),
+          ),
+        ),
+        // --- MODIFICATION: Body is now the IndexedStack directly ---
+        body: IndexedStack(
+          index: _currentStep,
+          children: <Widget>[
+            RiverInvesStep1SamplingInfo(
+              data: _samplingData,
+              onNext: _nextStep,
+            ),
+            RiverInvesStep2SiteInfo(
+              data: _samplingData,
+              onNext: _nextStep,
+            ),
+            RiverInvesStep3DataCapture(
+              data: _samplingData,
+              onNext: _nextStep,
+            ),
+            RiverInvesStep4AdditionalInfo(
+              data: _samplingData,
+              onNext: _nextStep,
+            ),
+            RiverInvesStep5Summary(
+              data: _samplingData,
+              onSubmit: _submitForm,
+              isLoading: _isLoading,
+            ),
+          ],
+        ),
+        // --- END MODIFICATION ---
+      ),
+    );
+  }
+}

lib/screens/river/river_home_page.dart

@@ -59,9 +59,11 @@ class RiverHomePage extends StatelessWidget {
       children: [
         // MODIFIED: Updated to point to the new Info Centre screen
         SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/river/investigative/info'),
-       // SidebarItem(icon: Icons.info, label: "Overview", route: '/river/investigative/overview'),
-        //SidebarItem(icon: Icons.input, label: "Entry", route: '/river/investigative/entry'),
-        //SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/river/investigative/report'),
+        // *** ADDED: Link to River Investigative Manual Sampling ***
+        SidebarItem(icon: Icons.biotech, label: "Investigative Sampling", route: '/river/investigative/manual-sampling'), // Added Icon
+        // SidebarItem(icon: Icons.info, label: "Overview", route: '/river/investigative/overview'), // Keep placeholder/future items commented
+        //SidebarItem(icon: Icons.input, label: "Entry", route: '/river/investigative/entry'), // Keep placeholder/future items commented
+        //SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/river/investigative/report'), // Keep placeholder/future items commented
       ],
     ),
   ];
@@ -136,30 +138,31 @@ class RiverHomePage extends StatelessWidget {
                   Navigator.pushNamed(context, subItem.route!);
                 }
               },
-              borderRadius: BorderRadius.circular(0),
+              borderRadius: BorderRadius.circular(0), // No rounded corners for grid items
               child: Container(
                 margin: const EdgeInsets.all(4.0), // Added margin for better spacing
                 decoration: BoxDecoration(
                   border: Border.all(color: Colors.white24, width: 0.5), // Optional: subtle border
+                  // No background color unless desired
                 ),
                 child: Padding(
                   padding: const EdgeInsets.all(8.0),
                   child: Row(
-                    mainAxisAlignment: MainAxisAlignment.start,
+                    mainAxisAlignment: MainAxisAlignment.start, // Align content to start
                     children: [
                       subItem.icon != null
-                          ? Icon(subItem.icon, color: Colors.white70, size: 24)
-                          : const SizedBox.shrink(),
+                          ? Icon(subItem.icon, color: Colors.white70, size: 24) // Adjusted icon size
+                          : const SizedBox.shrink(), // Or provide a placeholder
                       const SizedBox(width: 8),
-                      Expanded(
+                      Expanded( // Allow text to take remaining space
                         child: Text(
                           subItem.label,
                           style: Theme.of(context).textTheme.bodySmall?.copyWith(
-                            color: Colors.white70,
+                            color: Colors.white70, // Slightly lighter text
                             fontSize: 12, // Slightly increased font size
                           ),
-                          textAlign: TextAlign.left,
-                          overflow: TextOverflow.ellipsis,
+                          textAlign: TextAlign.left, // Left align text
+                          overflow: TextOverflow.ellipsis, // Prevent overflow
                           maxLines: 2, // Allow for two lines if needed
                         ),
                       ),
@@ -170,7 +173,7 @@ class RiverHomePage extends StatelessWidget {
             );
           },
         ),
-        const SizedBox(height: 16),
+        const SizedBox(height: 16), // Spacing between categories
       ],
     );
   }

lib/services/local_storage_service.dart

@@ -16,6 +16,11 @@ import '../models/in_situ_sampling_data.dart';
 import '../models/marine_manual_npe_report_data.dart';
 import '../models/river_in_situ_sampling_data.dart';
 import '../models/river_manual_triennial_sampling_data.dart';
+// --- ADDED IMPORT ---
+import '../models/marine_inves_manual_sampling_data.dart';
+// --- ADDED IMPORT FOR RIVER INVESTIGATIVE ---
+import '../models/river_inves_manual_sampling_data.dart';
+// --- END ADDED IMPORT ---
 
 class LocalStorageService {
 
@@ -803,6 +808,263 @@ class LocalStorageService {
     }
   }
 
+  // =======================================================================
+  // --- ADDED: Part 6.5: Marine Investigative Specific Methods ---
+  // =======================================================================
+
+  Future<Directory?> _getInvestigativeBaseDir({required String serverName}) async {
+    final mmsv4Dir = await _getPublicMMSV4Directory(serverName: serverName);
+    if (mmsv4Dir == null) return null;
+
+    // Use a new subModule path for investigative logs
+    final inSituDir = Directory(p.join(mmsv4Dir.path, 'marine', 'marine_investigative_sampling'));
+    if (!await inSituDir.exists()) {
+      await inSituDir.create(recursive: true);
+    }
+    return inSituDir;
+  }
+
+  /// Saves Marine Investigative sampling data to the local log
+  Future<String?> saveInvestigativeSamplingData(MarineInvesManualSamplingData data, {required String serverName}) async {
+    final baseDir = await _getInvestigativeBaseDir(serverName: serverName);
+    if (baseDir == null) {
+      debugPrint("Could not get public storage directory for Investigative. Check permissions.");
+      return null;
+    }
+
+    try {
+      // --- Generate folder name based on station type ---
+      String stationCode = 'NA';
+      if (data.stationTypeSelection == 'Existing Manual Station') {
+        stationCode = data.selectedStation?['man_station_code'] ?? 'MANUAL_NA';
+      } else if (data.stationTypeSelection == 'Existing Tarball Station') {
+        stationCode = data.selectedTarballStation?['tbl_station_code'] ?? 'TARBALL_NA';
+      } else if (data.stationTypeSelection == 'New Location') {
+        stationCode = data.newStationCode ?? 'NEW_NA';
+      }
+
+      final timestamp = "${data.samplingDate}_${data.samplingTime?.replaceAll(':', '-')}";
+      final eventFolderName = "${stationCode}_$timestamp";
+      final eventDir = Directory(p.join(baseDir.path, eventFolderName));
+
+      if (!await eventDir.exists()) {
+        await eventDir.create(recursive: true);
+      }
+
+      final Map<String, dynamic> jsonData = data.toDbJson(); //
+      jsonData['submissionStatus'] = data.submissionStatus;
+      jsonData['submissionMessage'] = data.submissionMessage;
+      jsonData['reportId'] = data.reportId;
+      jsonData['serverConfigName'] = serverName;
+
+      final imageFiles = data.toApiImageFiles(); //
+      for (var entry in imageFiles.entries) {
+        final File? imageFile = entry.value;
+        if (imageFile != null && imageFile.path.isNotEmpty) {
+          try {
+            // Check if file is already in the correct directory (e.g., from a retry)
+            if (p.dirname(imageFile.path) == eventDir.path) {
+              jsonData[entry.key] = imageFile.path;
+            } else {
+              // Copy file from temp cache to persistent log directory
+              final String originalFileName = p.basename(imageFile.path);
+              final File newFile = await imageFile.copy(p.join(eventDir.path, originalFileName));
+              jsonData[entry.key] = newFile.path;
+            }
+          } catch (e) {
+            debugPrint("Error processing Investigative image file ${imageFile.path}: $e");
+            jsonData[entry.key] = null;
+          }
+        }
+      }
+
+      final jsonFile = File(p.join(eventDir.path, 'data.json'));
+      await jsonFile.writeAsString(jsonEncode(jsonData));
+      debugPrint("Investigative log saved to: ${jsonFile.path}");
+
+      return eventDir.path; // Return the path to the saved log directory
+
+    } catch (e) {
+      debugPrint("Error saving Investigative log to local storage: $e");
+      return null;
+    }
+  }
+
+  /// Fetches all saved Marine Investigative logs
+  Future<List<Map<String, dynamic>>> getAllInvestigativeLogs() async {
+    final mmsv4Root = await _getPublicMMSV4Directory(serverName: '');
+    if (mmsv4Root == null || !await mmsv4Root.exists()) return [];
+
+    final List<Map<String, dynamic>> allLogs = [];
+    final serverDirs = mmsv4Root.listSync().whereType<Directory>();
+
+    for (var serverDir in serverDirs) {
+      final baseDir = Directory(p.join(serverDir.path, 'marine', 'marine_investigative_sampling'));
+      if (!await baseDir.exists()) continue;
+      try {
+        final entities = baseDir.listSync();
+        for (var entity in entities) {
+          if (entity is Directory) {
+            final jsonFile = File(p.join(entity.path, 'data.json'));
+            if (await jsonFile.exists()) {
+              final content = await jsonFile.readAsString();
+              final data = jsonDecode(content) as Map<String, dynamic>;
+              data['logDirectory'] = entity.path;
+              allLogs.add(data);
+            }
+          }
+        }
+      } catch (e) {
+        debugPrint("Error reading investigative logs from ${baseDir.path}: $e");
+      }
+    }
+    return allLogs;
+  }
+
+  /// Updates an existing Marine Investigative log file (e.g., after a retry)
+  Future<void> updateInvestigativeLog(Map<String, dynamic> updatedLogData) async {
+    final logDir = updatedLogData['logDirectory'];
+    if (logDir == null) {
+      debugPrint("Cannot update investigative log: logDirectory key is missing.");
+      return;
+    }
+
+    try {
+      final jsonFile = File(p.join(logDir, 'data.json'));
+      if (await jsonFile.exists()) {
+        updatedLogData.remove('isResubmitting'); // Clean up temporary flags
+        await jsonFile.writeAsString(jsonEncode(updatedLogData));
+        debugPrint("Investigative log updated successfully at: ${jsonFile.path}");
+      }
+    } catch (e) {
+      debugPrint("Error updating investigative log: $e");
+    }
+  }
+
+  // =======================================================================
+  // --- ADDED: Part 6.6: River Investigative Specific Methods ---
+  // =======================================================================
+
+  /// Gets the base directory for River Investigative logs.
+  Future<Directory?> getRiverInvestigativeBaseDir({required String serverName}) async {
+    final mmsv4Dir = await _getPublicMMSV4Directory(serverName: serverName);
+    if (mmsv4Dir == null) return null;
+
+    final invesDir = Directory(p.join(mmsv4Dir.path, 'river', 'river_investigative_sampling'));
+    if (!await invesDir.exists()) {
+      await invesDir.create(recursive: true);
+    }
+    return invesDir;
+  }
+
+  /// Saves River Investigative sampling data to the local log.
+  Future<String?> saveRiverInvestigativeSamplingData(RiverInvesManualSamplingData data, {required String serverName}) async {
+    final baseDir = await getRiverInvestigativeBaseDir(serverName: serverName);
+    if (baseDir == null) {
+      debugPrint("Could not get public storage directory for River Investigative. Check permissions.");
+      return null;
+    }
+
+    try {
+      final stationCode = data.getDeterminedStationCode() ?? 'UNKNOWN';
+      final timestamp = "${data.samplingDate}_${data.samplingTime?.replaceAll(':', '-')}";
+      final eventFolderName = "${stationCode}_$timestamp";
+      final eventDir = Directory(p.join(baseDir.path, eventFolderName));
+
+      if (!await eventDir.exists()) {
+        await eventDir.create(recursive: true);
+      }
+
+      // Use the .toMap() method from the data model, which is designed for local logging
+      final Map<String, dynamic> jsonData = data.toMap();
+      jsonData['serverConfigName'] = serverName;
+      // Status, message, and reportId are already included by .toMap()
+
+      final imageFiles = data.toApiImageFiles();
+      for (var entry in imageFiles.entries) {
+        final File? imageFile = entry.value;
+        if (imageFile != null && imageFile.path.isNotEmpty) {
+          try {
+            if (p.dirname(imageFile.path) == eventDir.path) {
+              jsonData[entry.key] = imageFile.path; // Already in log dir
+            } else {
+              final String originalFileName = p.basename(imageFile.path);
+              final File newFile = await imageFile.copy(p.join(eventDir.path, originalFileName));
+              jsonData[entry.key] = newFile.path; // Store the new persistent path
+            }
+          } catch (e) {
+            debugPrint("Error processing River Investigative image file ${imageFile.path}: $e");
+            jsonData[entry.key] = null; // Store null if copy failed
+          }
+        } else {
+          // Ensure keys for null images are also present if needed, though .toMap() handles this
+          jsonData[entry.key] = null;
+        }
+      }
+
+      final jsonFile = File(p.join(eventDir.path, 'data.json'));
+      await jsonFile.writeAsString(jsonEncode(jsonData));
+      debugPrint("River Investigative log saved to: ${jsonFile.path}");
+
+      return eventDir.path;
+
+    } catch (e) {
+      debugPrint("Error saving River Investigative log to local storage: $e");
+      return null;
+    }
+  }
+
+  /// Fetches all saved River Investigative logs.
+  Future<List<Map<String, dynamic>>> getAllRiverInvestigativeLogs() async {
+    final mmsv4Root = await _getPublicMMSV4Directory(serverName: '');
+    if (mmsv4Root == null || !await mmsv4Root.exists()) return [];
+
+    final List<Map<String, dynamic>> allLogs = [];
+    final serverDirs = mmsv4Root.listSync().whereType<Directory>();
+
+    for (var serverDir in serverDirs) {
+      final baseDir = Directory(p.join(serverDir.path, 'river', 'river_investigative_sampling'));
+      if (!await baseDir.exists()) continue;
+      try {
+        final entities = baseDir.listSync();
+        for (var entity in entities) {
+          if (entity is Directory) {
+            final jsonFile = File(p.join(entity.path, 'data.json'));
+            if (await jsonFile.exists()) {
+              final content = await jsonFile.readAsString();
+              final data = jsonDecode(content) as Map<String, dynamic>;
+              data['logDirectory'] = entity.path;
+              allLogs.add(data);
+            }
+          }
+        }
+      } catch (e) {
+        debugPrint("Error reading river investigative logs from ${baseDir.path}: $e");
+      }
+    }
+    return allLogs;
+  }
+
+  /// Updates an existing River Investigative log file (e.g., after a retry).
+  Future<void> updateRiverInvestigativeLog(Map<String, dynamic> updatedLogData) async {
+    final logDir = updatedLogData['logDirectory'];
+    if (logDir == null) {
+      debugPrint("Cannot update river investigative log: logDirectory key is missing.");
+      return;
+    }
+
+    try {
+      final jsonFile = File(p.join(logDir, 'data.json'));
+      if (await jsonFile.exists()) {
+        updatedLogData.remove('isResubmitting'); // Clean up temporary flags
+        await jsonFile.writeAsString(jsonEncode(updatedLogData));
+        debugPrint("River Investigative log updated successfully at: ${jsonFile.path}");
+      }
+    } catch (e) {
+      debugPrint("Error updating river investigative log: $e");
+    }
+  }
+
 
   // =======================================================================
   // --- ADDED: Part 7: Info Centre Document Management ---

lib/services/marine_in_situ_sampling_service.dart

@@ -166,21 +166,26 @@ class MarineInSituSamplingService {
     required InSituSamplingData data,
     required List<Map<String, dynamic>>? appSettings,
     required AuthProvider authProvider,
-    BuildContext? context,
+    BuildContext? context, // Context no longer needed here, but kept for signature consistency
     String? logDirectory,
   }) async {
     const String moduleName = 'marine_in_situ';
 
     final connectivityResult = await Connectivity().checkConnectivity();
-    bool isOnline = connectivityResult != ConnectivityResult.none;
+    bool isOnline = !connectivityResult.contains(ConnectivityResult.none);
     bool isOfflineSession = authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
 
     if (isOnline && isOfflineSession) {
       debugPrint("In-Situ submission online during offline session. Attempting auto-relogin...");
+      try {
         final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
         if (transitionSuccess) {
           isOfflineSession = false;
         } else {
+          isOnline = false; // Auto-relogin failed, treat as offline
+        }
+      } on SessionExpiredException catch (_) {
+        debugPrint("Session expired during auto-relogin check. Treating as offline.");
         isOnline = false;
       }
     }
@@ -199,15 +204,17 @@ class MarineInSituSamplingService {
       return await _performOfflineQueuing(
         data: data,
         moduleName: moduleName,
+        logDirectory: logDirectory, // Pass for potential update
       );
     }
   }
 
+  /// Handles the online submission flow using generic services.
   Future<Map<String, dynamic>> _performOnlineSubmission({
     required InSituSamplingData data,
     required List<Map<String, dynamic>>? appSettings,
     required String moduleName,
-    required AuthProvider authProvider,
+    required AuthProvider authProvider, // Still needed for session check inside this method
     String? logDirectory,
   }) async {
     final serverName = (await _serverConfigService.getActiveApiConfig())?['config_name'] as String? ?? 'Default';
@@ -218,25 +225,29 @@ class MarineInSituSamplingService {
     bool anyApiSuccess = false;
     Map<String, dynamic> apiDataResult = {};
     Map<String, dynamic> apiImageResult = {};
+    String finalMessage = '';
+    String finalStatus = '';
     bool isSessionKnownToBeExpired = false;
 
     try {
+      // 1. Submit Form Data
       apiDataResult = await _submissionApiService.submitPost(
         moduleName: moduleName,
-        endpoint: 'marine/manual/sample',
+        endpoint: 'marine/manual/sample', // Correct endpoint for In-Situ data
         body: data.toApiFormData(),
       );
 
       if (apiDataResult['success'] == true) {
         anyApiSuccess = true;
-        data.reportId = apiDataResult['data']?['man_id']?.toString();
+        data.reportId = apiDataResult['data']?['man_id']?.toString(); // Correct ID key for In-Situ
 
         if (data.reportId != null) {
           if (finalImageFiles.isNotEmpty) {
+            // 2. Submit Images
             apiImageResult = await _submissionApiService.submitMultipart(
               moduleName: moduleName,
-              endpoint: 'marine/manual/images',
-              fields: {'man_id': data.reportId!},
+              endpoint: 'marine/manual/images', // Correct endpoint for In-Situ images
+              fields: {'man_id': data.reportId!}, // Correct field key for In-Situ
               files: finalImageFiles,
             );
             if (apiImageResult['success'] != true) {
@@ -248,65 +259,92 @@ class MarineInSituSamplingService {
           apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
         }
       }
-    } on SessionExpiredException catch (_) {
-      debugPrint("API submission failed with SessionExpiredException. Attempting silent relogin...");
-      final bool reloginSuccess = await authProvider.attemptSilentRelogin();
+      // If apiDataResult['success'] is false, SubmissionApiService queued it.
 
-      if (reloginSuccess) {
-        debugPrint("Silent relogin successful. Retrying entire online submission process...");
-        return await _performOnlineSubmission(
-          data: data,
-          appSettings: appSettings,
-          moduleName: moduleName,
-          authProvider: authProvider,
-          logDirectory: logDirectory,
-        );
-      } else {
-        debugPrint("Silent relogin failed. API part will be queued, proceeding with FTP.");
+    } on SessionExpiredException catch (_) {
+      debugPrint("Online submission failed due to session expiry that could not be refreshed.");
       isSessionKnownToBeExpired = true;
       anyApiSuccess = false;
       apiDataResult = {'success': false, 'message': 'Session expired and re-login failed. API submission queued.'};
-        await _retryService.addApiToQueue(endpoint: 'marine/manual/sample', method: 'POST', body: data.toApiFormData());
-      }
-    } on SocketException catch (e) {
-      final errorMessage = "API submission failed with network error: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
+      // Manually queue API calls
       await _retryService.addApiToQueue(endpoint: 'marine/manual/sample', method: 'POST', body: data.toApiFormData());
       if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        // Also queue images if data call might have partially succeeded before expiry
         await _retryService.addApiToQueue(endpoint: 'marine/manual/images', method: 'POST_MULTIPART', fields: {'man_id': data.reportId!}, files: finalImageFiles);
       }
-    } on TimeoutException catch (e) {
-      final errorMessage = "API submission timed out: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
-      await _retryService.addApiToQueue(endpoint: 'marine/manual/sample', method: 'POST', body: data.toApiFormData());
     }
 
+    // 3. Submit FTP Files
     Map<String, dynamic> ftpResults = {'statuses': []};
     bool anyFtpSuccess = false;
+
+    if (isSessionKnownToBeExpired) {
+      debugPrint("Skipping FTP attempt due to known expired session. Manually queuing FTP tasks.");
+      final baseFileNameForQueue = _generateBaseFileName(data); // Use helper
+
+      // --- START FIX: Add ftpConfigId when queuing ---
+      final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
+
+      final dataZip = await _zippingService.createDataZip(
+        jsonDataMap: {'db.json': jsonEncode(data.toDbJson())},
+        baseFileName: baseFileNameForQueue,
+        destinationDir: null, // Use temp dir
+      );
+      if (dataZip != null) {
+        // Queue for each config separately
+        for (final config in ftpConfigs) {
+          final configId = config['ftp_config_id'];
+          if (configId != null) {
+            await _retryService.addFtpToQueue(
+                localFilePath: dataZip.path,
+                remotePath: '/${p.basename(dataZip.path)}',
+                ftpConfigId: configId // Provide the specific config ID
+            );
+          }
+        }
+      }
+
+      if (finalImageFiles.isNotEmpty) {
+        final imageZip = await _zippingService.createImageZip(
+          imageFiles: finalImageFiles.values.toList(),
+          baseFileName: baseFileNameForQueue,
+          destinationDir: null, // Use temp dir
+        );
+        if (imageZip != null) {
+          // Queue for each config separately
+          for (final config in ftpConfigs) {
+            final configId = config['ftp_config_id'];
+            if (configId != null) {
+              await _retryService.addFtpToQueue(
+                  localFilePath: imageZip.path,
+                  remotePath: '/${p.basename(imageZip.path)}',
+                  ftpConfigId: configId // Provide the specific config ID
+              );
+            }
+          }
+        }
+      }
+      // --- END FIX ---
+      ftpResults = {'statuses': [{'status': 'Queued', 'message': 'FTP upload queued due to API session issue.', 'success': false}]};
+      anyFtpSuccess = false;
+    } else {
       try {
         ftpResults = await _generateAndUploadFtpFiles(data, finalImageFiles, serverName, moduleName);
         anyFtpSuccess = !(ftpResults['statuses'] as List).any((status) => status['success'] == false && status['status'] != 'Not Configured');
-    } on SocketException catch (e) {
-      debugPrint("FTP submission failed with network error: $e");
-      anyFtpSuccess = false;
-    } on TimeoutException catch (e) {
-      debugPrint("FTP submission timed out: $e");
+      } catch (e) {
+        debugPrint("Unexpected FTP submission error: $e");
         anyFtpSuccess = false;
       }
+    }
 
+    // 4. Determine Final Status
     final bool overallSuccess = anyApiSuccess || anyFtpSuccess;
-    String finalMessage;
-    String finalStatus;
 
     if (anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'Data submitted successfully to all destinations.';
       finalStatus = 'S4';
     } else if (anyApiSuccess && !anyFtpSuccess) {
-      finalMessage = 'Data sent to API, but some FTP uploads failed and were queued.';
+      finalMessage = 'Data sent to API, but some FTP uploads failed or were queued.';
       finalStatus = 'S3';
     } else if (!anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
@@ -316,6 +354,7 @@ class MarineInSituSamplingService {
       finalStatus = 'L1';
     }
 
+    // 5. Log Locally
     await _logAndSave(
       data: data,
       status: finalStatus,
@@ -323,10 +362,11 @@ class MarineInSituSamplingService {
       apiResults: [apiDataResult, apiImageResult],
       ftpStatuses: ftpResults['statuses'],
       serverName: serverName,
-      finalImageFiles: finalImageFiles,
+      finalImageFiles: finalImageFiles, // Pass the map of actual files
       logDirectory: logDirectory,
     );
 
+    // 6. Send Alert
     if (overallSuccess) {
       _handleInSituSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty, isSessionExpired: isSessionKnownToBeExpired);
     }
@@ -334,55 +374,88 @@ class MarineInSituSamplingService {
     return {'success': overallSuccess, 'message': finalMessage, 'reportId': data.reportId};
   }
 
+
+  /// Handles queuing the submission data when the device is offline.
   Future<Map<String, dynamic>> _performOfflineQueuing({
     required InSituSamplingData data,
     required String moduleName,
+    String? logDirectory, // Added for potential update
   }) async {
     final serverConfig = await _serverConfigService.getActiveApiConfig();
     final serverName = serverConfig?['config_name'] as String? ?? 'Default';
 
-    // Set initial status before first save
     data.submissionStatus = 'L1';
     data.submissionMessage = 'Submission queued for later retry.';
 
-    final String? localLogPath = await _localStorageService.saveInSituSamplingData(data, serverName: serverName);
+    String? savedLogPath = logDirectory; // Use existing path if provided
 
-    if (localLogPath == null) {
+    // Save/Update local log first
+    if (savedLogPath != null && savedLogPath.isNotEmpty) {
+      // Need to reconstruct the map with file paths for updating
+      Map<String, dynamic> logUpdateData = data.toDbJson();
+      final imageFiles = data.toApiImageFiles();
+      imageFiles.forEach((key, file) {
+        logUpdateData[key] = file?.path; // Add paths back
+      });
+      logUpdateData['logDirectory'] = savedLogPath;
+      await _localStorageService.updateInSituLog(logUpdateData);
+      debugPrint("Updated existing In-Situ log for queuing: $savedLogPath");
+    } else {
+      savedLogPath = await _localStorageService.saveInSituSamplingData(data, serverName: serverName);
+      debugPrint("Saved new In-Situ log for queuing: $savedLogPath");
+    }
+
+
+    if (savedLogPath == null) {
       const message = "Failed to save submission to local device storage.";
-      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {});
+      // Use empty map for finalImageFiles as saving failed
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {}, logDirectory: logDirectory);
       return {'success': false, 'message': message};
     }
 
+    // Use the correct task type for In-Situ retry
     await _retryService.queueTask(
       type: 'insitu_submission',
       payload: {
         'module': moduleName,
-        'localLogPath': localLogPath,
+        'localLogPath': savedLogPath, // Pass directory path
         'serverConfig': serverConfig,
       },
     );
 
-    const successMessage = "Submission failed to send and has been queued for later retry.";
-    return {'success': true, 'message': successMessage};
+    const successMessage = "Device offline. Submission has been saved locally and queued for automatic retry when connection is restored.";
+    // Log final queued state to central DB
+    // await _logAndSave(data: data, status: 'Queued', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {}, logDirectory: savedLogPath);
+
+    return {'success': true, 'message': successMessage, 'reportId': null}; // No report ID yet
   }
 
-  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(InSituSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+  /// Helper to generate the base filename for ZIP files.
+  String _generateBaseFileName(InSituSamplingData data) {
     final stationCode = data.selectedStation?['man_station_code'] ?? 'NA';
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
-    final baseFileName = '${stationCode}_$fileTimestamp';
+    return '${stationCode}_$fileTimestamp';
+  }
+
+  /// Generates data and image ZIP files and uploads them using SubmissionFtpService.
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(InSituSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+    final baseFileName = _generateBaseFileName(data);
 
     final Directory? logDirectory = await _localStorageService.getLogDirectory(
       serverName: serverName,
       module: 'marine',
-      subModule: 'marine_in_situ_sampling',
+      subModule: 'marine_in_situ_sampling', // Correct sub-module path
     );
-    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
+    final folderName = data.reportId ?? baseFileName;
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, folderName)) : null;
+
     if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
       await localSubmissionDir.create(recursive: true);
     }
 
+    // Create and upload data ZIP
     final dataZip = await _zippingService.createDataZip(
-      jsonDataMap: {'db.json': jsonEncode(data.toDbJson())},
+      jsonDataMap: {'db.json': jsonEncode(data.toDbJson())}, // Use toDbJson for FTP
       baseFileName: baseFileName,
       destinationDir: localSubmissionDir,
     );
@@ -395,6 +468,7 @@ class MarineInSituSamplingService {
       );
     }
 
+    // Create and upload image ZIP
     final imageZip = await _zippingService.createImageZip(
       imageFiles: imageFiles.values.toList(),
       baseFileName: baseFileName,
@@ -411,12 +485,13 @@ class MarineInSituSamplingService {
 
     return {
       'statuses': <Map<String, dynamic>>[
-        ...(ftpDataResult['statuses'] as List<dynamic>? ?? []),
-        ...(ftpImageResult['statuses'] as List<dynamic>? ?? []),
+        ...(ftpDataResult['statuses'] as List? ?? []), // Use null-aware spread
+        ...(ftpImageResult['statuses'] as List? ?? []), // Use null-aware spread
       ],
     };
   }
 
+  /// Saves or updates the local log file and saves a record to the central DB log.
   Future<void> _logAndSave({
     required InSituSamplingData data,
     required String status,
@@ -424,64 +499,110 @@ class MarineInSituSamplingService {
     required List<Map<String, dynamic>> apiResults,
     required List<Map<String, dynamic>> ftpStatuses,
     required String serverName,
-    required Map<String, File> finalImageFiles,
+    required Map<String, File> finalImageFiles, // Changed to Map<String, File>
     String? logDirectory,
   }) async {
     data.submissionStatus = status;
     data.submissionMessage = message;
-    final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
+    final baseFileName = _generateBaseFileName(data); // Use helper
 
-    if (logDirectory != null) {
-      final Map<String, dynamic> updatedLogData = data.toDbJson();
-
-      updatedLogData['submissionStatus'] = status;
-      updatedLogData['submissionMessage'] = message;
-
-      updatedLogData['logDirectory'] = logDirectory;
-      updatedLogData['serverConfigName'] = serverName;
-      updatedLogData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
-      updatedLogData['ftp_status'] = jsonEncode(ftpStatuses);
-
-      final imageFilePaths = data.toApiImageFiles();
-      imageFilePaths.forEach((key, file) {
-        if (file != null) {
-          updatedLogData[key] = file.path;
-        }
+    // Prepare log data map including file paths
+    Map<String, dynamic> logMapData = data.toDbJson();
+    final imageFileMap = data.toApiImageFiles();
+    imageFileMap.forEach((key, file) {
+      logMapData[key] = file?.path; // Store path or null
     });
+    // Add submission metadata
+    logMapData['submissionStatus'] = status;
+    logMapData['submissionMessage'] = message;
+    logMapData['reportId'] = data.reportId;
+    logMapData['serverConfigName'] = serverName;
+    logMapData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
+    logMapData['ftp_status'] = jsonEncode(ftpStatuses);
 
-      await _localStorageService.updateInSituLog(updatedLogData);
+    if (logDirectory != null && logDirectory.isNotEmpty) {
+      // Update existing log
+      logMapData['logDirectory'] = logDirectory; // Ensure logDirectory path is in the map
+      await _localStorageService.updateInSituLog(logMapData);
     } else {
+      // Save new log - saveInSituSamplingData handles adding file paths
       await _localStorageService.saveInSituSamplingData(data, serverName: serverName);
     }
 
 
+    // Save to central DB log
     final logData = {
-      'submission_id': data.reportId ?? fileTimestamp,
+      'submission_id': data.reportId ?? baseFileName, // Use helper result
       'module': 'marine',
-      'type': 'In-Situ',
-      'status': data.submissionStatus,
-      'message': data.submissionMessage,
+      'type': 'In-Situ', // Correct type
+      'status': status,
+      'message': message,
       'report_id': data.reportId,
       'created_at': DateTime.now().toIso8601String(),
-      'form_data': jsonEncode(data.toDbJson()),
-      'image_data': jsonEncode(finalImageFiles.values.map((f) => f.path).toList()),
+      'form_data': jsonEncode(logMapData), // Log the comprehensive map with paths
+      'image_data': jsonEncode(finalImageFiles.values.map((f) => f.path).toList()), // List of paths for files actually submitted/zipped
       'server_name': serverName,
       'api_status': jsonEncode(apiResults),
       'ftp_status': jsonEncode(ftpStatuses),
     };
+    try {
       await _dbHelper.saveSubmissionLog(logData);
+    } catch (e) {
+      debugPrint("Error saving In-Situ submission log to DB: $e");
+    }
   }
 
+
+  /// Handles sending or queuing the Telegram alert for In-Situ submissions.
   Future<void> _handleInSituSuccessAlert(InSituSamplingData data, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly, bool isSessionExpired = false}) async {
+
+    // --- START: Logic moved from data model ---
+    String generateInSituTelegramAlertMessage(InSituSamplingData data, {required bool isDataOnly}) {
+      final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
+      final stationName = data.selectedStation?['man_station_name'] ?? 'N/A';
+      final stationCode = data.selectedStation?['man_station_code'] ?? 'N/A';
+
+      final buffer = StringBuffer()
+        ..writeln('✅ *In-Situ Sample $submissionType Submitted:*')
+        ..writeln()
+        ..writeln('*Station Name & Code:* $stationName ($stationCode)')
+        ..writeln('*Date of Submission:* ${data.samplingDate}')
+        ..writeln('*Submitted by User:* ${data.firstSamplerName}')
+        ..writeln('*Sonde ID:* ${data.sondeId ?? "N/A"}')
+        ..writeln('*Status of Submission:* Successful');
+
+      final distanceKm = data.distanceDifferenceInKm ?? 0;
+      final distanceRemarks = data.distanceDifferenceRemarks ?? '';
+      if (distanceKm * 1000 > 50) { // Check distance > 50m
+        buffer
+          ..writeln()
+          ..writeln('🔔 *Distance Alert:*')
+          ..writeln('*Distance from station:* ${(distanceKm * 1000).toStringAsFixed(0)} meters');
+
+        if (distanceRemarks.isNotEmpty) {
+          buffer.writeln('*Remarks for distance:* $distanceRemarks');
+        }
+      }
+
+      // Note: The logic to check parameter limits requires async DB access,
+      // which cannot be done directly here without further refactoring.
+      // This part is omitted for now as per the previous refactor.
+
+      return buffer.toString();
+    }
+    // --- END: Logic moved from data model ---
+
     try {
-      final message = data.generateTelegramAlertMessage(isDataOnly: isDataOnly);
+      final message = generateInSituTelegramAlertMessage(data, isDataOnly: isDataOnly); // Call local function
+      final alertKey = 'marine_in_situ'; // Correct key
+
       if (isSessionExpired) {
-        debugPrint("Session is expired; queuing Telegram alert directly.");
-        await _telegramService.queueMessage('marine_in_situ', message, appSettings);
+        debugPrint("Session is expired; queuing Telegram alert directly for $alertKey.");
+        await _telegramService.queueMessage(alertKey, message, appSettings);
       } else {
-        final bool wasSent = await _telegramService.sendAlertImmediately('marine_in_situ', message, appSettings);
+        final bool wasSent = await _telegramService.sendAlertImmediately(alertKey, message, appSettings);
         if (!wasSent) {
-          await _telegramService.queueMessage('marine_in_situ', message, appSettings);
+          await _telegramService.queueMessage(alertKey, message, appSettings);
         }
       }
     } catch (e) {

lib/services/marine_investigative_sampling_service.dart

@@ -0,0 +1,629 @@
+// lib/services/marine_investigative_sampling_service.dart
+
+import 'dart:async';
+import 'dart:io';
+import 'dart:convert';
+import 'package:flutter/material.dart'; // Needed for debugPrint and BuildContext
+import 'package:flutter/services.dart';
+import 'package:image_picker/image_picker.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:path/path.dart' as p;
+import 'package:image/image.dart' as img;
+import 'package:geolocator/geolocator.dart';
+import 'package:permission_handler/permission_handler.dart';
+import 'package:flutter_bluetooth_serial/flutter_bluetooth_serial.dart';
+import 'package:usb_serial/usb_serial.dart';
+import 'package:connectivity_plus/connectivity_plus.dart';
+
+import '../auth_provider.dart';
+import 'location_service.dart';
+import '../models/marine_inves_manual_sampling_data.dart';
+import '../bluetooth/bluetooth_manager.dart';
+import '../serial/serial_manager.dart';
+import 'local_storage_service.dart';
+import 'server_config_service.dart';
+import 'zipping_service.dart';
+import 'submission_api_service.dart';
+import 'submission_ftp_service.dart';
+import 'telegram_service.dart';
+import 'retry_service.dart';
+import 'base_api_service.dart'; // Import for SessionExpiredException
+import 'api_service.dart'; // Import for DatabaseHelper
+
+/// A dedicated service for the Marine Investigative Sampling feature.
+class MarineInvestigativeSamplingService {
+  // Business Logic Services
+  final LocationService _locationService = LocationService();
+  final BluetoothManager _bluetoothManager = BluetoothManager();
+  final SerialManager _serialManager = SerialManager();
+
+  // Submission & Utility Services
+  final SubmissionApiService _submissionApiService = SubmissionApiService();
+  final SubmissionFtpService _submissionFtpService = SubmissionFtpService();
+  final ZippingService _zippingService = ZippingService();
+  final LocalStorageService _localStorageService = LocalStorageService();
+  final ServerConfigService _serverConfigService = ServerConfigService();
+  final DatabaseHelper _dbHelper = DatabaseHelper();
+  final RetryService _retryService = RetryService();
+  final TelegramService _telegramService;
+
+  MarineInvestigativeSamplingService(this._telegramService);
+
+  static const platform = MethodChannel('com.example.environment_monitoring_app/usb');
+
+  // --- Location Services ---
+  Future<Position> getCurrentLocation() => _locationService.getCurrentLocation();
+  double calculateDistance(double lat1, double lon1, double lat2, double lon2) => _locationService.calculateDistance(lat1, lon1, lat2, lon2);
+
+  // --- Image Processing ---
+  Future<File?> pickAndProcessImage(ImageSource source, {
+    required MarineInvesManualSamplingData data,
+    required String imageInfo,
+    bool isRequired = false,
+  }) async {
+    final picker = ImagePicker();
+    final XFile? photo = await picker.pickImage(source: source, imageQuality: 85, maxWidth: 1024);
+    if (photo == null) return null;
+
+    final bytes = await photo.readAsBytes();
+    img.Image? originalImage = img.decodeImage(bytes);
+    if (originalImage == null) return null;
+
+    if (isRequired && originalImage.height > originalImage.width) {
+      debugPrint("Image rejected: Must be in landscape orientation.");
+      return null;
+    }
+
+    final String watermarkTimestamp = "${data.samplingDate} ${data.samplingTime}";
+    final font = img.arial24;
+    final textWidth = watermarkTimestamp.length * 12; // Approximate width calculation
+    // Ensure overlay box fits the text
+    img.fillRect(originalImage, x1: 5, y1: 5, x2: textWidth + 15, y2: 35, color: img.ColorRgb8(255, 255, 255));
+    img.drawString(originalImage, watermarkTimestamp, font: font, x: 10, y: 10, color: img.ColorRgb8(0, 0, 0));
+
+    final tempDir = await getTemporaryDirectory();
+
+    String stationCode = 'NA';
+    if (data.stationTypeSelection == 'Existing Manual Station') {
+      stationCode = data.selectedStation?['man_station_code'] ?? 'MANUAL_NA';
+    } else if (data.stationTypeSelection == 'Existing Tarball Station') {
+      stationCode = data.selectedTarballStation?['tbl_station_code'] ?? 'TARBALL_NA';
+    } else if (data.stationTypeSelection == 'New Location') {
+      stationCode = data.newStationCode ?? 'NEW_NA';
+    }
+
+    final fileTimestamp = "${data.samplingDate}-${data.samplingTime}".replaceAll(':', '-');
+    final newFileName = "${stationCode}_${fileTimestamp}_${imageInfo.replaceAll(' ', '')}.jpg";
+    final filePath = p.join(tempDir.path, newFileName);
+
+    File processedFile = File(filePath);
+    await processedFile.writeAsBytes(img.encodeJpg(originalImage));
+    return processedFile;
+  }
+
+
+  // --- Device Connection (Delegated to Managers) ---
+  ValueNotifier<BluetoothConnectionState> get bluetoothConnectionState => _bluetoothManager.connectionState;
+  ValueNotifier<SerialConnectionState> get serialConnectionState => _serialManager.connectionState;
+  ValueNotifier<String?> get sondeId => _bluetoothManager.connectionState.value != BluetoothConnectionState.disconnected ? _bluetoothManager.sondeId : _serialManager.sondeId;
+  Stream<Map<String, double>> get bluetoothDataStream => _bluetoothManager.dataStream;
+  Stream<Map<String, double>> get serialDataStream => _serialManager.dataStream;
+  String? get connectedBluetoothDeviceName => _bluetoothManager.connectedDeviceName.value;
+  String? get connectedSerialDeviceName => _serialManager.connectedDeviceName.value;
+
+  // --- Permissions ---
+  Future<bool> requestDevicePermissions() async {
+    Map<Permission, PermissionStatus> statuses = await [
+      Permission.bluetoothScan,
+      Permission.bluetoothConnect,
+      Permission.locationWhenInUse,
+    ].request();
+
+    if (statuses[Permission.bluetoothScan] == PermissionStatus.granted &&
+        statuses[Permission.bluetoothConnect] == PermissionStatus.granted &&
+        statuses[Permission.locationWhenInUse] == PermissionStatus.granted) {
+      return true;
+    } else {
+      debugPrint("Bluetooth or Location permissions denied.");
+      return false;
+    }
+  }
+
+
+  // --- Bluetooth Methods ---
+  Future<List<BluetoothDevice>> getPairedBluetoothDevices() => _bluetoothManager.getPairedDevices();
+  Future<void> connectToBluetoothDevice(BluetoothDevice device) => _bluetoothManager.connect(device);
+  void disconnectFromBluetooth() => _bluetoothManager.disconnect();
+  void startBluetoothAutoReading({Duration? interval}) => _bluetoothManager.startAutoReading(interval: interval ?? const Duration(seconds: 2));
+  void stopBluetoothAutoReading() => _bluetoothManager.stopAutoReading();
+
+  // --- USB Serial Methods ---
+  Future<List<UsbDevice>> getAvailableSerialDevices() => _serialManager.getAvailableDevices();
+  Future<bool> requestUsbPermission(UsbDevice device) async {
+    try {
+      final bool? granted = await platform.invokeMethod('requestUsbPermission', {'vid': device.vid, 'pid': device.pid});
+      return granted ?? false;
+    } on PlatformException catch (e) {
+      debugPrint("Failed to request USB permission: '${e.message}'.");
+      return false;
+    }
+  }
+
+  Future<void> connectToSerialDevice(UsbDevice device) async {
+    final bool permissionGranted = await requestUsbPermission(device);
+    if (permissionGranted) {
+      await _serialManager.connect(device);
+    } else {
+      throw Exception("USB permission was not granted.");
+    }
+  }
+
+  void disconnectFromSerial() => _serialManager.disconnect();
+  void startSerialAutoReading({Duration? interval}) => _serialManager.startAutoReading(interval: interval ?? const Duration(seconds: 2));
+  void stopSerialAutoReading() => _serialManager.stopAutoReading();
+
+  void dispose() {
+    _bluetoothManager.dispose();
+    _serialManager.dispose();
+  }
+
+  Future<Map<String, dynamic>> submitInvestigativeSample({
+    required MarineInvesManualSamplingData data,
+    required List<Map<String, dynamic>>? appSettings,
+    required AuthProvider authProvider,
+    BuildContext? context,
+    String? logDirectory,
+  }) async {
+    const String moduleName = 'marine_investigative';
+
+    final connectivityResult = await Connectivity().checkConnectivity();
+    bool isOnline = !connectivityResult.contains(ConnectivityResult.none);
+    bool isOfflineSession = authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
+
+    if (isOnline && isOfflineSession) {
+      debugPrint("Investigative submission online during offline session. Attempting auto-relogin...");
+      try {
+        final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
+        if (transitionSuccess) {
+          isOfflineSession = false;
+        } else {
+          isOnline = false; // Auto-relogin failed, treat as offline
+        }
+      } on SessionExpiredException catch (_) {
+        debugPrint("Session expired during auto-relogin check. Treating as offline.");
+        isOnline = false;
+      }
+    }
+
+    if (isOnline && !isOfflineSession) {
+      debugPrint("Proceeding with direct ONLINE Investigative submission...");
+      return await _performOnlineSubmission(
+        data: data,
+        appSettings: appSettings,
+        moduleName: moduleName,
+        authProvider: authProvider,
+        logDirectory: logDirectory,
+      );
+    } else {
+      debugPrint("Proceeding with OFFLINE Investigative queuing mechanism...");
+      return await _performOfflineQueuing(
+        data: data,
+        moduleName: moduleName,
+        logDirectory: logDirectory, // Pass for potential update
+      );
+    }
+  }
+
+  Future<Map<String, dynamic>> _performOnlineSubmission({
+    required MarineInvesManualSamplingData data,
+    required List<Map<String, dynamic>>? appSettings,
+    required String moduleName,
+    required AuthProvider authProvider,
+    String? logDirectory,
+  }) async {
+    final serverName = (await _serverConfigService.getActiveApiConfig())?['config_name'] as String? ?? 'Default';
+    final imageFilesWithNulls = data.toApiImageFiles();
+    imageFilesWithNulls.removeWhere((key, value) => value == null);
+    final Map<String, File> finalImageFiles = imageFilesWithNulls.cast<String, File>();
+
+    bool anyApiSuccess = false;
+    Map<String, dynamic> apiDataResult = {};
+    Map<String, dynamic> apiImageResult = {};
+    String finalMessage = '';
+    String finalStatus = '';
+    bool isSessionKnownToBeExpired = false;
+
+    try {
+      // 1. Submit Form Data
+      apiDataResult = await _submissionApiService.submitPost(
+        moduleName: moduleName,
+        endpoint: 'marine/investigative/sample',
+        body: data.toApiFormData(),
+      );
+
+      if (apiDataResult['success'] == true) {
+        anyApiSuccess = true;
+        data.reportId = apiDataResult['data']?['man_inves_id']?.toString();
+
+        if (data.reportId != null) {
+          if (finalImageFiles.isNotEmpty) {
+            // 2. Submit Images
+            apiImageResult = await _submissionApiService.submitMultipart(
+              moduleName: moduleName,
+              endpoint: 'marine/investigative/images',
+              fields: {'man_inves_id': data.reportId!},
+              files: finalImageFiles,
+            );
+            if (apiImageResult['success'] != true) {
+              anyApiSuccess = false; // Mark as failed if images fail
+            }
+          }
+        } else {
+          anyApiSuccess = false;
+          apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
+        }
+      }
+    } on SessionExpiredException catch (_) {
+      debugPrint("Online submission failed due to session expiry that could not be refreshed.");
+      isSessionKnownToBeExpired = true; // Mark session as expired
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': 'Session expired and re-login failed. API submission queued.'};
+      // Manually queue the API call since SubmissionApiService was never called or failed internally due to session
+      await _retryService.addApiToQueue(endpoint: 'marine/investigative/sample', method: 'POST', body: data.toApiFormData());
+      if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        // Also queue images if data call might have partially succeeded before expiry
+        await _retryService.addApiToQueue(endpoint: 'marine/investigative/images', method: 'POST_MULTIPART', fields: {'man_inves_id': data.reportId!}, files: finalImageFiles);
+      }
+    }
+    // We no longer catch SocketException or TimeoutException here.
+
+    // 3. Submit FTP Files
+    Map<String, dynamic> ftpResults = {'statuses': []};
+    bool anyFtpSuccess = false;
+
+    if (isSessionKnownToBeExpired) {
+      debugPrint("Skipping FTP attempt due to known expired session. Manually queuing FTP tasks.");
+      final baseFileNameForQueue = _generateBaseFileName(data);
+
+      // --- START FIX: Add ftpConfigId when queuing ---
+      final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
+
+      final dataZip = await _zippingService.createDataZip(
+        jsonDataMap: {'db.json': jsonEncode(data.toDbJson())},
+        baseFileName: baseFileNameForQueue,
+        destinationDir: null, // Use temp dir
+      );
+      if (dataZip != null) {
+        // Queue for each config separately
+        for (final config in ftpConfigs) {
+          final configId = config['ftp_config_id'];
+          if (configId != null) {
+            await _retryService.addFtpToQueue(
+                localFilePath: dataZip.path,
+                remotePath: '/${p.basename(dataZip.path)}',
+                ftpConfigId: configId // Provide the specific config ID
+            );
+          }
+        }
+      }
+
+      if (finalImageFiles.isNotEmpty) {
+        final imageZip = await _zippingService.createImageZip(
+          imageFiles: finalImageFiles.values.toList(),
+          baseFileName: baseFileNameForQueue,
+          destinationDir: null, // Use temp dir
+        );
+        if (imageZip != null) {
+          // Queue for each config separately
+          for (final config in ftpConfigs) {
+            final configId = config['ftp_config_id'];
+            if (configId != null) {
+              await _retryService.addFtpToQueue(
+                  localFilePath: imageZip.path,
+                  remotePath: '/${p.basename(imageZip.path)}',
+                  ftpConfigId: configId // Provide the specific config ID
+              );
+            }
+          }
+        }
+      }
+      // --- END FIX ---
+      ftpResults = {'statuses': [{'status': 'Queued', 'message': 'FTP upload queued due to API session issue.', 'success': false}]};
+      anyFtpSuccess = false;
+
+    } else {
+      // Session is OK, proceed with normal FTP attempt
+      try {
+        // _generateAndUploadFtpFiles already uses the generic SubmissionFtpService
+        ftpResults = await _generateAndUploadFtpFiles(data, finalImageFiles, serverName, moduleName);
+        // Check if *any* configured FTP target succeeded (excluding 'Not Configured')
+        anyFtpSuccess = !(ftpResults['statuses'] as List).any((status) => status['success'] == false && status['status'] != 'Not Configured');
+      } catch (e) {
+        debugPrint("Unexpected FTP submission error: $e");
+        anyFtpSuccess = false; // FTP failures are auto-queued by SubmissionFtpService
+      }
+    }
+
+    // 4. Determine Final Status
+    final bool overallSuccess = anyApiSuccess || anyFtpSuccess;
+
+    if (anyApiSuccess && anyFtpSuccess) {
+      finalMessage = 'Data submitted successfully to all destinations.';
+      finalStatus = 'S4';
+    } else if (anyApiSuccess && !anyFtpSuccess) {
+      finalMessage = 'Data sent to API, but some FTP uploads failed or were queued.';
+      finalStatus = 'S3';
+    } else if (!anyApiSuccess && anyFtpSuccess) {
+      finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
+      finalStatus = 'L4';
+    } else {
+      finalMessage = apiDataResult['message'] ?? 'All submission attempts failed and have been queued for retry.';
+      finalStatus = 'L1';
+    }
+
+    // 5. Log Locally
+    await _logAndSave(
+      data: data,
+      status: finalStatus,
+      message: finalMessage,
+      apiResults: [apiDataResult, apiImageResult],
+      ftpStatuses: ftpResults['statuses'],
+      serverName: serverName,
+      finalImageFiles: finalImageFiles,
+      logDirectory: logDirectory,
+    );
+
+    // 6. Send Alert
+    if (overallSuccess) {
+      _handleInvestigativeSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty, isSessionExpired: isSessionKnownToBeExpired);
+    }
+
+    return {'success': overallSuccess, 'message': finalMessage, 'reportId': data.reportId};
+  }
+
+
+  Future<Map<String, dynamic>> _performOfflineQueuing({
+    required MarineInvesManualSamplingData data,
+    required String moduleName,
+    String? logDirectory, // Added for potential update
+  }) async {
+    final serverConfig = await _serverConfigService.getActiveApiConfig();
+    final serverName = serverConfig?['config_name'] as String? ?? 'Default';
+
+    data.submissionStatus = 'L1';
+    data.submissionMessage = 'Submission queued for later retry.';
+
+    String? savedLogPath = logDirectory; // Use existing path if provided
+
+    // Save/Update local log first
+    if (savedLogPath != null && savedLogPath.isNotEmpty) {
+      // Prepare map with file paths for update
+      Map<String, dynamic> logUpdateData = data.toDbJson();
+      final imageFiles = data.toApiImageFiles();
+      imageFiles.forEach((key, file) {
+        logUpdateData[key] = file?.path; // Add paths back
+      });
+      logUpdateData['logDirectory'] = savedLogPath;
+      await _localStorageService.updateInvestigativeLog(logUpdateData);
+      debugPrint("Updated existing Investigative log for queuing: $savedLogPath");
+    } else {
+      savedLogPath = await _localStorageService.saveInvestigativeSamplingData(data, serverName: serverName);
+      debugPrint("Saved new Investigative log for queuing: $savedLogPath");
+    }
+
+    if (savedLogPath == null) {
+      const message = "Failed to save submission to local device storage.";
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {}, logDirectory: logDirectory);
+      return {'success': false, 'message': message};
+    }
+
+    await _retryService.queueTask(
+      type: 'investigative_submission',
+      payload: {
+        'module': moduleName,
+        'localLogPath': savedLogPath, // Pass directory path
+        'serverConfig': serverConfig,
+      },
+    );
+
+    const successMessage = "Device offline. Submission has been saved locally and queued for automatic retry when connection is restored.";
+    // Log final queued state to central DB
+    // await _logAndSave(data: data, status: 'Queued', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {}, logDirectory: savedLogPath);
+
+    return {'success': true, 'message': successMessage, 'reportId': null}; // No report ID yet
+  }
+
+  String _generateBaseFileName(MarineInvesManualSamplingData data) {
+    String stationCode = 'NA';
+    if (data.stationTypeSelection == 'Existing Manual Station') {
+      stationCode = data.selectedStation?['man_station_code'] ?? 'MANUAL_NA';
+    } else if (data.stationTypeSelection == 'Existing Tarball Station') {
+      stationCode = data.selectedTarballStation?['tbl_station_code'] ?? 'TARBALL_NA';
+    } else if (data.stationTypeSelection == 'New Location') {
+      stationCode = data.newStationCode ?? 'NEW_NA';
+    }
+    final datePart = data.samplingDate ?? 'NODATE';
+    final timePart = (data.samplingTime ?? 'NOTIME').replaceAll(':', '-');
+    final fileTimestamp = "${datePart}_${timePart}".replaceAll(' ', '_');
+    return '${stationCode}_$fileTimestamp';
+  }
+
+
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(MarineInvesManualSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+    final baseFileName = _generateBaseFileName(data);
+
+    final Directory? logDirectory = await _localStorageService.getLogDirectory(
+      serverName: serverName,
+      module: 'marine',
+      subModule: 'marine_investigative_sampling',
+    );
+    final folderName = data.reportId ?? baseFileName;
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, folderName)) : null;
+
+    if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
+      try {
+        await localSubmissionDir.create(recursive: true);
+      } catch (e) {
+        debugPrint("Error creating local submission directory ${localSubmissionDir.path}: $e");
+      }
+    }
+
+    final dataZip = await _zippingService.createDataZip(
+      jsonDataMap: {'db.json': jsonEncode(data.toDbJson())},
+      baseFileName: baseFileName,
+      destinationDir: localSubmissionDir,
+    );
+    Map<String, dynamic> ftpDataResult = {'success': true, 'statuses': []};
+    if (dataZip != null) {
+      ftpDataResult = await _submissionFtpService.submit(
+        moduleName: moduleName,
+        fileToUpload: dataZip,
+        remotePath: '/${p.basename(dataZip.path)}',
+      );
+    } else {
+      debugPrint("Data ZIP file was null, skipping FTP upload for data.");
+    }
+
+    final imageZip = await _zippingService.createImageZip(
+      imageFiles: imageFiles.values.toList(),
+      baseFileName: baseFileName,
+      destinationDir: localSubmissionDir,
+    );
+    Map<String, dynamic> ftpImageResult = {'success': true, 'statuses': []};
+    if (imageZip != null) {
+      ftpImageResult = await _submissionFtpService.submit(
+        moduleName: moduleName,
+        fileToUpload: imageZip,
+        remotePath: '/${p.basename(imageZip.path)}',
+      );
+    } else {
+      debugPrint("Image ZIP file was null, skipping FTP upload for images.");
+    }
+
+    return {
+      'statuses': <Map<String, dynamic>>[
+        ...(ftpDataResult['statuses'] as List? ?? []),
+        ...(ftpImageResult['statuses'] as List? ?? []),
+      ],
+    };
+  }
+
+
+  Future<void> _logAndSave({
+    required MarineInvesManualSamplingData data,
+    required String status,
+    required String message,
+    required List<Map<String, dynamic>> apiResults,
+    required List<Map<String, dynamic>> ftpStatuses,
+    required String serverName,
+    required Map<String, File> finalImageFiles, // Use final images map
+    String? logDirectory, // Existing log directory path if updating
+  }) async {
+    data.submissionStatus = status;
+    data.submissionMessage = message;
+    final baseFileName = _generateBaseFileName(data);
+
+    // Prepare log data map including file paths
+    Map<String, dynamic> logMapData = data.toDbJson();
+    final imageFileMap = data.toApiImageFiles();
+    imageFileMap.forEach((key, file) {
+      logMapData[key] = file?.path; // Store path or null
+    });
+    // Add submission metadata
+    logMapData['submissionStatus'] = status;
+    logMapData['submissionMessage'] = message;
+    logMapData['reportId'] = data.reportId;
+    logMapData['serverConfigName'] = serverName;
+    logMapData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
+    logMapData['ftp_status'] = jsonEncode(ftpStatuses);
+
+
+    if (logDirectory != null && logDirectory.isNotEmpty) {
+      logMapData['logDirectory'] = logDirectory; // Ensure path is in map
+      await _localStorageService.updateInvestigativeLog(logMapData); // Use specific update
+    } else {
+      await _localStorageService.saveInvestigativeSamplingData(data, serverName: serverName); // Use specific save
+    }
+
+    final logData = {
+      'submission_id': data.reportId ?? baseFileName,
+      'module': 'marine',
+      'type': 'Investigative',
+      'status': status,
+      'message': message,
+      'report_id': data.reportId,
+      'created_at': DateTime.now().toIso8601String(),
+      'form_data': jsonEncode(logMapData), // Log comprehensive map
+      'image_data': jsonEncode(finalImageFiles.values.map((f) => f.path).toList()),
+      'server_name': serverName,
+      'api_status': jsonEncode(apiResults),
+      'ftp_status': jsonEncode(ftpStatuses),
+    };
+    try {
+      await _dbHelper.saveSubmissionLog(logData);
+    } catch (e) {
+      debugPrint("Error saving Investigative submission log to DB: $e");
+    }
+  }
+
+
+  Future<void> _handleInvestigativeSuccessAlert(MarineInvesManualSamplingData data, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly, bool isSessionExpired = false}) async {
+
+    String generateInvestigativeTelegramAlertMessage(MarineInvesManualSamplingData data, {required bool isDataOnly}) {
+      final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
+
+      String stationName = 'N/A';
+      String stationCode = 'N/A';
+
+      if (data.stationTypeSelection == 'Existing Manual Station') {
+        stationName = data.selectedStation?['man_station_name'] ?? 'N/A';
+        stationCode = data.selectedStation?['man_station_code'] ?? 'N/A';
+      } else if (data.stationTypeSelection == 'Existing Tarball Station') {
+        stationName = data.selectedTarballStation?['tbl_station_name'] ?? 'N/A';
+        stationCode = data.selectedTarballStation?['tbl_station_code'] ?? 'N/A';
+      } else if (data.stationTypeSelection == 'New Location') {
+        stationName = data.newStationName ?? 'New Location';
+        stationCode = data.newStationCode ?? 'NEW';
+      }
+
+      final buffer = StringBuffer()
+        ..writeln('🕵️ *Marine Investigative Sample $submissionType Submitted:*')
+        ..writeln()
+        ..writeln('*Station Name & Code:* $stationName ($stationCode)')
+        ..writeln('*Date of Submitted:* ${data.samplingDate}')
+        ..writeln('*Submitted by User:* ${data.firstSamplerName}')
+        ..writeln('*Sonde ID:* ${data.sondeId ?? "N/A"}')
+        ..writeln('*Status of Submission:* Successful');
+
+      if (data.distanceDifferenceInKm != null && data.distanceDifferenceInKm! * 1000 > 50) {
+        buffer
+          ..writeln()
+          ..writeln('🔔 *Distance Alert:*')
+          ..writeln('*Distance from station:* ${(data.distanceDifferenceInKm! * 1000).toStringAsFixed(0)} meters');
+
+        if (data.distanceDifferenceRemarks != null && data.distanceDifferenceRemarks!.isNotEmpty) {
+          buffer.writeln('*Remarks for distance:* ${data.distanceDifferenceRemarks}');
+        }
+      }
+
+      return buffer.toString();
+    }
+
+    try {
+      final message = generateInvestigativeTelegramAlertMessage(data, isDataOnly: isDataOnly);
+      final alertKey = 'marine_investigative';
+
+      if (isSessionExpired) {
+        debugPrint("Session is expired; queuing Telegram alert directly for $alertKey.");
+        await _telegramService.queueMessage(alertKey, message, appSettings);
+      } else {
+        final bool wasSent = await _telegramService.sendAlertImmediately(alertKey, message, appSettings);
+        if (!wasSent) {
+          await _telegramService.queueMessage(alertKey, message, appSettings);
+        }
+      }
+    } catch (e) {
+      debugPrint("Failed to handle Investigative Telegram alert: $e");
+    }
+  }
+}

lib/services/marine_tarball_sampling_service.dart

@@ -37,38 +37,62 @@ class MarineTarballSamplingService {
   Future<Map<String, dynamic>> submitTarballSample({
     required TarballSamplingData data,
     required List<Map<String, dynamic>>? appSettings,
-    required BuildContext context,
+    // --- START FIX: Make BuildContext nullable ---
+    required BuildContext? context,
+    // --- END FIX ---
+    String? logDirectory, // Added for retry consistency
   }) async {
     const String moduleName = 'marine_tarball';
-    final authProvider = Provider.of<AuthProvider>(context, listen: false);
+    // --- START FIX: Handle nullable context ---
+    final authProvider = context != null ? Provider.of<AuthProvider>(context, listen: false) : null;
+    // Need a fallback mechanism if context is null (e.g., during retry)
+    // One option is to ensure AuthProvider is always accessible, maybe via a singleton or passed differently.
+    // For now, we'll proceed assuming authProvider might be null during retry,
+    // which could affect session checks. Consider injecting AuthProvider if needed globally.
+    if (authProvider == null && context != null) {
+      // If context was provided but provider failed, log error
+      debugPrint("Error: AuthProvider not found in context for Tarball submission.");
+      return {'success': false, 'message': 'Internal error: AuthProvider not available.'};
+    }
+    // --- END FIX ---
 
     final connectivityResult = await Connectivity().checkConnectivity();
-    bool isOnline = connectivityResult != ConnectivityResult.none;
-    bool isOfflineSession = authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
+    bool isOnline = !connectivityResult.contains(ConnectivityResult.none);
+    // --- START FIX: Handle potentially null authProvider ---
+    bool isOfflineSession = authProvider != null && authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
 
-    if (isOnline && isOfflineSession) {
-      debugPrint("Submission initiated online during an offline session. Attempting auto-relogin...");
+    if (isOnline && isOfflineSession && authProvider != null) {
+      debugPrint("Tarball submission online during an offline session. Attempting auto-relogin...");
+      try {
         final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
         if (transitionSuccess) {
           isOfflineSession = false;
         } else {
+          isOnline = false; // Auto-relogin failed, treat as offline
+        }
+      } on SessionExpiredException catch (_) {
+        debugPrint("Session expired during auto-relogin check. Treating as offline.");
         isOnline = false;
       }
     }
+    // --- END FIX ---
+
 
     if (isOnline && !isOfflineSession) {
-      debugPrint("Proceeding with direct ONLINE submission...");
+      debugPrint("Proceeding with direct ONLINE Tarball submission...");
       return await _performOnlineSubmission(
         data: data,
         appSettings: appSettings,
         moduleName: moduleName,
-        authProvider: authProvider,
+        authProvider: authProvider, // Pass potentially null provider
+        logDirectory: logDirectory,
       );
     } else {
-      debugPrint("Proceeding with OFFLINE queuing mechanism...");
+      debugPrint("Proceeding with OFFLINE Tarball queuing mechanism...");
       return await _performOfflineQueuing(
         data: data,
         moduleName: moduleName,
+        logDirectory: logDirectory, // Pass logDirectory for potential update
       );
     }
   }
@@ -77,7 +101,8 @@ class MarineTarballSamplingService {
     required TarballSamplingData data,
     required List<Map<String, dynamic>>? appSettings,
     required String moduleName,
-    required AuthProvider authProvider,
+    required AuthProvider? authProvider, // Accept potentially null provider
+    String? logDirectory, // Added for retry consistency
   }) async {
     final serverName = (await _serverConfigService.getActiveApiConfig())?['config_name'] as String? ?? 'Default';
     final imageFiles = data.toImageFiles()..removeWhere((key, value) => value == null);
@@ -86,92 +111,133 @@ class MarineTarballSamplingService {
     bool anyApiSuccess = false;
     Map<String, dynamic> apiDataResult = {};
     Map<String, dynamic> apiImageResult = {};
+    String finalMessage = '';
+    String finalStatus = '';
     bool isSessionKnownToBeExpired = false;
 
     try {
+      // 1. Submit Form Data
       apiDataResult = await _submissionApiService.submitPost(
         moduleName: moduleName,
-        endpoint: 'marine/tarball/sample',
-        body: data.toFormData(),
+        endpoint: 'marine/tarball/sample', // Correct endpoint
+        body: data.toFormData(), // Use specific method for tarball form data
       );
 
       if (apiDataResult['success'] == true) {
         anyApiSuccess = true;
-        data.reportId = apiDataResult['data']?['autoid']?.toString();
+        data.reportId = apiDataResult['data']?['autoid']?.toString(); // Correct ID key
 
         if (data.reportId != null) {
+          if (finalImageFiles.isNotEmpty) {
+            // 2. Submit Images
             apiImageResult = await _submissionApiService.submitMultipart(
               moduleName: moduleName,
-            endpoint: 'marine/tarball/images',
-            fields: {'autoid': data.reportId!},
+              endpoint: 'marine/tarball/images', // Correct endpoint
+              fields: {'autoid': data.reportId!}, // Correct field key
               files: finalImageFiles,
             );
             if (apiImageResult['success'] != true) {
               anyApiSuccess = false; // Downgrade success if images fail
             }
+          }
+          // If data succeeded but no images, API part is still successful
         } else {
           anyApiSuccess = false;
           apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
         }
       }
-    } on SessionExpiredException catch (_) {
-      debugPrint("API submission failed with SessionExpiredException. Attempting silent relogin...");
-      final bool reloginSuccess = await authProvider.attemptSilentRelogin();
+      // If apiDataResult['success'] is false, SubmissionApiService queued it.
 
-      if (reloginSuccess) {
-        debugPrint("Silent relogin successful. Retrying entire online submission process...");
-        return await _performOnlineSubmission(
-          data: data,
-          appSettings: appSettings,
-          moduleName: moduleName,
-          authProvider: authProvider,
-        );
-      } else {
-        debugPrint("Silent relogin failed. API part will be queued, proceeding with FTP.");
+    } on SessionExpiredException catch (_) {
+      debugPrint("API submission failed with SessionExpiredException during online submission.");
       isSessionKnownToBeExpired = true;
       anyApiSuccess = false;
-        apiDataResult = {'success': false, 'message': 'Session expired and re-login failed. API submission queued.'};
-        await _retryService.addApiToQueue(endpoint: 'marine/tarball/sample', method: 'POST', body: data.toFormData());
-      }
-    } on SocketException catch (e) {
-      final errorMessage = "API submission failed with network error: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
+      apiDataResult = {'success': false, 'message': 'Session expired. API submission queued.'};
+      // Manually queue API calls
       await _retryService.addApiToQueue(endpoint: 'marine/tarball/sample', method: 'POST', body: data.toFormData());
       if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        // Queue images if data might have partially succeeded
         await _retryService.addApiToQueue(endpoint: 'marine/tarball/images', method: 'POST_MULTIPART', fields: {'autoid': data.reportId!}, files: finalImageFiles);
       }
-    } on TimeoutException catch (e) {
-      final errorMessage = "API submission timed out: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
-      await _retryService.addApiToQueue(endpoint: 'marine/tarball/sample', method: 'POST', body: data.toFormData());
     }
 
+    // 3. Submit FTP Files
     Map<String, dynamic> ftpResults = {'statuses': []};
     bool anyFtpSuccess = false;
-    try {
-      ftpResults = await _generateAndUploadFtpFiles(data, finalImageFiles, serverName, moduleName);
-      anyFtpSuccess = !ftpResults['statuses'].any((status) => status['success'] == false);
-    } on SocketException catch (e) {
-      debugPrint("FTP submission failed with network error: $e");
-      anyFtpSuccess = false;
-    } on TimeoutException catch (e) {
-      debugPrint("FTP submission timed out: $e");
-      anyFtpSuccess = false;
+
+    if (isSessionKnownToBeExpired) {
+      debugPrint("Skipping FTP attempt due to known expired session. Manually queuing FTP tasks.");
+      final baseFileNameForQueue = _generateBaseFileName(data); // Use helper
+
+      // --- START FIX: Add ftpConfigId when queuing ---
+      final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
+
+      final dataZip = await _zippingService.createDataZip(
+        jsonDataMap: { // Use specific JSON structures for Tarball FTP
+          'data.json': jsonEncode(data.toDbJson()),
+          'basic_form.json': jsonEncode(data.toBasicFormJson()),
+          'reading.json': jsonEncode(data.toReadingJson()),
+          'manual_info.json': jsonEncode(data.toManualInfoJson()),
+        },
+        baseFileName: baseFileNameForQueue,
+        destinationDir: null,
+      );
+      if (dataZip != null) {
+        // Queue for each config separately
+        for (final config in ftpConfigs) {
+          final configId = config['ftp_config_id'];
+          if (configId != null) {
+            await _retryService.addFtpToQueue(
+                localFilePath: dataZip.path,
+                remotePath: '/${p.basename(dataZip.path)}',
+                ftpConfigId: configId // Provide the specific config ID
+            );
+          }
+        }
       }
 
+      if (finalImageFiles.isNotEmpty) {
+        final imageZip = await _zippingService.createImageZip(
+          imageFiles: finalImageFiles.values.toList(),
+          baseFileName: baseFileNameForQueue,
+          destinationDir: null,
+        );
+        if (imageZip != null) {
+          // Queue for each config separately
+          for (final config in ftpConfigs) {
+            final configId = config['ftp_config_id'];
+            if (configId != null) {
+              await _retryService.addFtpToQueue(
+                  localFilePath: imageZip.path,
+                  remotePath: '/${p.basename(imageZip.path)}',
+                  ftpConfigId: configId // Provide the specific config ID
+              );
+            }
+          }
+        }
+      }
+      // --- END FIX ---
+      ftpResults = {'statuses': [{'status': 'Queued', 'message': 'FTP upload queued due to API session issue.', 'success': false}]};
+      anyFtpSuccess = false;
+    } else {
+      try {
+        ftpResults = await _generateAndUploadFtpFiles(data, finalImageFiles, serverName, moduleName);
+        anyFtpSuccess = !(ftpResults['statuses'] as List).any((status) => status['success'] == false && status['status'] != 'Not Configured');
+      } catch (e) {
+        debugPrint("Unexpected FTP submission error: $e");
+        anyFtpSuccess = false;
+      }
+    }
+
+
+    // 4. Determine Final Status
     final bool overallSuccess = anyApiSuccess || anyFtpSuccess;
-    String finalMessage;
-    String finalStatus;
 
     if (anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'Data submitted successfully to all destinations.';
       finalStatus = 'S4';
     } else if (anyApiSuccess && !anyFtpSuccess) {
-      finalMessage = 'Data sent to API, but some FTP uploads failed and were queued.';
+      finalMessage = 'Data sent to API, but some FTP uploads failed or were queued.';
       finalStatus = 'S3';
     } else if (!anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
@@ -181,6 +247,7 @@ class MarineTarballSamplingService {
       finalStatus = 'L1';
     }
 
+    // 5. Log Locally
     await _logAndSave(
       data: data,
       status: finalStatus,
@@ -189,8 +256,10 @@ class MarineTarballSamplingService {
       ftpStatuses: ftpResults['statuses'],
       serverName: serverName,
       finalImageFiles: finalImageFiles,
+      logDirectory: logDirectory, // Pass logDirectory for potential update
     );
 
+    // 6. Send Alert
     if (overallSuccess) {
       _handleTarballSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty, isSessionExpired: isSessionKnownToBeExpired);
     }
@@ -201,50 +270,82 @@ class MarineTarballSamplingService {
   Future<Map<String, dynamic>> _performOfflineQueuing({
     required TarballSamplingData data,
     required String moduleName,
+    String? logDirectory, // Added for potential update
   }) async {
     final serverConfig = await _serverConfigService.getActiveApiConfig();
     final serverName = serverConfig?['config_name'] as String? ?? 'Default';
 
-    final String? localLogPath = await _localStorageService.saveTarballSamplingData(data, serverName: serverName);
+    // Set status before saving/updating
+    data.submissionStatus = 'L1'; // Logged locally or Queued
+    data.submissionMessage = 'Submission queued for later retry.';
 
-    if (localLogPath == null) {
+    String? savedLogPath = logDirectory; // Use existing path if provided
+
+    // Save/Update local log first
+    if (savedLogPath != null && savedLogPath.isNotEmpty) {
+      await _localStorageService.updateTarballLog(data.toDbJson()..['logDirectory'] = savedLogPath);
+      debugPrint("Updated existing Tarball log for queuing: $savedLogPath");
+    } else {
+      savedLogPath = await _localStorageService.saveTarballSamplingData(data, serverName: serverName);
+      debugPrint("Saved new Tarball log for queuing: $savedLogPath");
+    }
+
+
+    if (savedLogPath == null) {
       const message = "Failed to save submission to local device storage.";
-      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {});
+      // Log failure state if saving fails
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {}, logDirectory: logDirectory);
       return {'success': false, 'message': message};
     }
 
+    // Queue a single task for the RetryService
     await _retryService.queueTask(
-      type: 'tarball_submission',
+      type: 'tarball_submission', // Use specific type
       payload: {
         'module': moduleName,
-        'localLogPath': localLogPath,
+        'localLogPath': savedLogPath, // Point retry service to the saved log *directory*
         'serverConfig': serverConfig,
       },
     );
 
-    const successMessage = "Submission failed to send and has been queued for later retry.";
-    await _logAndSave(data: data, status: 'Queued', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {});
+    const successMessage = "Device offline. Submission has been saved locally and queued for automatic retry when connection is restored.";
+    // Log final queued state to central DB
+    // await _logAndSave(data: data, status: 'Queued', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {}, logDirectory: savedLogPath);
 
-    return {'success': true, 'message': successMessage};
+    return {'success': true, 'message': successMessage, 'reportId': null}; // No report ID yet
   }
 
-  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(TarballSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+  /// Helper to generate the base filename for ZIP files.
+  String _generateBaseFileName(TarballSamplingData data) {
     final stationCode = data.selectedStation?['tbl_station_code'] ?? 'NA';
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
-    final baseFileName = '${stationCode}_$fileTimestamp';
+    return '${stationCode}_$fileTimestamp';
+  }
+
+  /// Generates data and image ZIP files and uploads them using SubmissionFtpService.
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(TarballSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+    final baseFileName = _generateBaseFileName(data);
 
     final Directory? logDirectory = await _localStorageService.getLogDirectory(
       serverName: serverName,
       module: 'marine',
-      subModule: 'marine_tarball_sampling',
+      subModule: 'marine_tarball_sampling', // Correct sub-module
     );
-    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
+    final folderName = data.reportId ?? baseFileName;
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, folderName)) : null;
+
     if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
       await localSubmissionDir.create(recursive: true);
     }
 
+    // Create and upload data ZIP (with multiple JSON files specific to Tarball)
     final dataZip = await _zippingService.createDataZip(
-      jsonDataMap: {'data.json': jsonEncode(data.toDbJson())},
+      jsonDataMap: {
+        'data.json': jsonEncode(data.toDbJson()), // Use specific method
+        'basic_form.json': jsonEncode(data.toBasicFormJson()), // Use specific method
+        'reading.json': jsonEncode(data.toReadingJson()), // Use specific method
+        'manual_info.json': jsonEncode(data.toManualInfoJson()), // Use specific method
+      },
       baseFileName: baseFileName,
       destinationDir: localSubmissionDir,
     );
@@ -257,6 +358,7 @@ class MarineTarballSamplingService {
       );
     }
 
+    // Create and upload image ZIP
     final imageZip = await _zippingService.createImageZip(
       imageFiles: imageFiles.values.toList(),
       baseFileName: baseFileName,
@@ -273,12 +375,13 @@ class MarineTarballSamplingService {
 
     return {
       'statuses': <Map<String, dynamic>>[
-        ...?(ftpDataResult['statuses'] as List?),
-        ...?(ftpImageResult['statuses'] as List?),
+        ...(ftpDataResult['statuses'] as List? ?? []),
+        ...(ftpImageResult['statuses'] as List? ?? []),
       ],
     };
   }
 
+  /// Saves or updates the local log file and saves a record to the central DB log.
   Future<void> _logAndSave({
     required TarballSamplingData data,
     required String status,
@@ -287,40 +390,103 @@ class MarineTarballSamplingService {
     required List<Map<String, dynamic>> ftpStatuses,
     required String serverName,
     required Map<String, File> finalImageFiles,
+    String? logDirectory, // Added for potential update
   }) async {
     data.submissionStatus = status;
     data.submissionMessage = message;
-    final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
+    final baseFileName = _generateBaseFileName(data); // Use helper
 
-    await _localStorageService.saveTarballSamplingData(data, serverName: serverName);
+    // Prepare log data map including file paths
+    Map<String, dynamic> logMapData = data.toDbJson();
+    final imageFileMap = data.toImageFiles();
+    imageFileMap.forEach((key, file) {
+      logMapData[key] = file?.path; // Store path or null
+    });
+    // Add submission metadata
+    logMapData['submissionStatus'] = status;
+    logMapData['submissionMessage'] = message;
+    logMapData['reportId'] = data.reportId;
+    logMapData['serverConfigName'] = serverName;
+    logMapData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
+    logMapData['ftp_status'] = jsonEncode(ftpStatuses);
 
+    // Update or save the specific local JSON log file
+    if (logDirectory != null && logDirectory.isNotEmpty) {
+      logMapData['logDirectory'] = logDirectory; // Ensure logDirectory path is in the map
+      await _localStorageService.updateTarballLog(logMapData); // Use specific update method
+    } else {
+      await _localStorageService.saveTarballSamplingData(data, serverName: serverName); // Use specific save method
+    }
+
+    // Save a record to the central SQLite submission log table
     final logData = {
-      'submission_id': data.reportId ?? fileTimestamp,
-      'module': 'marine',
-      'type': 'Tarball',
+      'submission_id': data.reportId ?? baseFileName, // Use helper result
+      'module': 'marine', // Correct module
+      'type': 'Tarball', // Correct type
       'status': status,
       'message': message,
       'report_id': data.reportId,
       'created_at': DateTime.now().toIso8601String(),
-      'form_data': jsonEncode(data.toDbJson()),
+      'form_data': jsonEncode(logMapData), // Log the comprehensive map with paths
       'image_data': jsonEncode(finalImageFiles.values.map((f) => f.path).toList()),
       'server_name': serverName,
       'api_status': jsonEncode(apiResults),
       'ftp_status': jsonEncode(ftpStatuses),
     };
+    try {
       await _dbHelper.saveSubmissionLog(logData);
+    } catch (e) {
+      debugPrint("Error saving Tarball submission log to DB: $e");
+    }
   }
 
+  /// Handles sending or queuing the Telegram alert for Tarball submissions.
   Future<void> _handleTarballSuccessAlert(TarballSamplingData data, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly, bool isSessionExpired = false}) async {
+
+    // --- START: Logic moved from data model ---
+    String generateTarballTelegramAlertMessage(TarballSamplingData data, {required bool isDataOnly}) {
+      final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
+      final stationName = data.selectedStation?['tbl_station_name'] ?? 'N/A';
+      final stationCode = data.selectedStation?['tbl_station_code'] ?? 'N/A';
+      final classification = data.selectedClassification?['classification_name'] ?? data.classificationId?.toString() ?? 'N/A';
+
+      final buffer = StringBuffer()
+        ..writeln('✅ *Tarball Sample $submissionType Submitted:*')
+        ..writeln()
+        ..writeln('*Station Name & Code:* $stationName ($stationCode)')
+        ..writeln('*Date of Submission:* ${data.samplingDate}')
+        ..writeln('*Submitted by User:* ${data.firstSampler}') // Use firstSampler from data model
+        ..writeln('*Classification:* $classification')
+        ..writeln('*Status of Submission:* Successful');
+
+      final distanceKm = data.distanceDifference ?? 0; // Use distanceDifference from data model
+      final distanceRemarks = data.distanceDifferenceRemarks ?? '';
+      if (distanceKm * 1000 > 50) { // Check distance > 50m
+        buffer
+          ..writeln()
+          ..writeln('🔔 *Distance Alert:*')
+          ..writeln('*Distance from station:* ${(distanceKm * 1000).toStringAsFixed(0)} meters');
+
+        if (distanceRemarks.isNotEmpty) {
+          buffer.writeln('*Remarks for distance:* $distanceRemarks');
+        }
+      }
+
+      return buffer.toString();
+    }
+    // --- END: Logic moved from data model ---
+
     try {
-      final message = data.generateTelegramAlertMessage(isDataOnly: isDataOnly);
+      final message = generateTarballTelegramAlertMessage(data, isDataOnly: isDataOnly); // Call local function
+      final alertKey = 'marine_tarball'; // Correct key
+
       if (isSessionExpired) {
-        debugPrint("Session is expired; queuing Telegram alert directly.");
-        await _telegramService.queueMessage('marine_tarball', message, appSettings);
+        debugPrint("Session is expired; queuing Telegram alert directly for $alertKey.");
+        await _telegramService.queueMessage(alertKey, message, appSettings);
       } else {
-        final bool wasSent = await _telegramService.sendAlertImmediately('marine_tarball', message, appSettings);
+        final bool wasSent = await _telegramService.sendAlertImmediately(alertKey, message, appSettings);
         if (!wasSent) {
-          await _telegramService.queueMessage('marine_tarball', message, appSettings);
+          await _telegramService.queueMessage(alertKey, message, appSettings);
         }
       }
     } catch (e) {

lib/services/retry_service.dart

@@ -7,8 +7,16 @@ import 'package:path/path.dart' as p;
 
 import 'package:environment_monitoring_app/models/in_situ_sampling_data.dart';
 import 'package:environment_monitoring_app/services/marine_in_situ_sampling_service.dart';
-import 'package:environment_monitoring_app/models/river_in_situ_sampling_data.dart'; // ADDED
-import 'package:environment_monitoring_app/services/river_in_situ_sampling_service.dart'; // ADDED
+import 'package:environment_monitoring_app/models/river_in_situ_sampling_data.dart';
+import 'package:environment_monitoring_app/services/river_in_situ_sampling_service.dart';
+// *** ADDED: Import River Investigative Model and Service ***
+import 'package:environment_monitoring_app/models/river_inves_manual_sampling_data.dart';
+import 'package:environment_monitoring_app/services/river_investigative_sampling_service.dart';
+// *** END ADDED ***
+import 'package:environment_monitoring_app/models/marine_inves_manual_sampling_data.dart';
+import 'package:environment_monitoring_app/services/marine_investigative_sampling_service.dart';
+import 'package:environment_monitoring_app/models/tarball_data.dart';
+import 'package:environment_monitoring_app/services/marine_tarball_sampling_service.dart';
 import 'package:environment_monitoring_app/services/api_service.dart';
 import 'package:environment_monitoring_app/services/base_api_service.dart';
 import 'package:environment_monitoring_app/services/ftp_service.dart';
@@ -23,23 +31,32 @@ class RetryService {
   final ServerConfigService _serverConfigService = ServerConfigService();
   bool _isProcessing = false;
 
-  // --- START: MODIFICATION FOR HANDLING COMPLEX TASKS ---
-  // These services will be provided after the RetryService is created.
   MarineInSituSamplingService? _marineInSituService;
-  RiverInSituSamplingService? _riverInSituService; // ADDED
+  RiverInSituSamplingService? _riverInSituService;
+  MarineInvestigativeSamplingService? _marineInvestigativeService;
+  MarineTarballSamplingService? _marineTarballService;
+  // *** ADDED: River Investigative Service member ***
+  RiverInvestigativeSamplingService? _riverInvestigativeService;
+  // *** END ADDED ***
   AuthProvider? _authProvider;
 
-  // Call this method from your main app setup to provide the necessary services.
+  // *** MODIFIED: Added riverInvestigativeService to initialize ***
   void initialize({
     required MarineInSituSamplingService marineInSituService,
-    required RiverInSituSamplingService riverInSituService, // ADDED
+    required RiverInSituSamplingService riverInSituService,
+    required MarineInvestigativeSamplingService marineInvestigativeService,
+    required RiverInvestigativeSamplingService riverInvestigativeService, // <-- Added parameter
+    required MarineTarballSamplingService marineTarballService,
     required AuthProvider authProvider,
   }) {
     _marineInSituService = marineInSituService;
-    _riverInSituService = riverInSituService; // ADDED
+    _riverInSituService = riverInSituService;
+    _marineInvestigativeService = marineInvestigativeService;
+    _riverInvestigativeService = riverInvestigativeService; // <-- Assign parameter
+    _marineTarballService = marineTarballService;
     _authProvider = authProvider;
   }
-  // --- END: MODIFICATION FOR HANDLING COMPLEX TASKS ---
+  // *** END MODIFIED ***
 
 
   /// Adds a generic, complex task to the queue, to be handled by a background processor.
@@ -49,7 +66,7 @@ class RetryService {
   }) async {
     await _dbHelper.queueFailedRequest({
       'type': type,
-      'endpoint_or_path': 'N/A',
+      'endpoint_or_path': 'N/A', // Not applicable for complex tasks initially
       'payload': jsonEncode(payload),
       'timestamp': DateTime.now().toIso8601String(),
       'status': 'pending',
@@ -65,12 +82,13 @@ class RetryService {
     Map<String, String>? fields,
     Map<String, File>? files,
   }) async {
+    // Convert File objects to paths for JSON serialization
     final serializableFiles = files?.map((key, value) => MapEntry(key, value.path));
     final payload = {
       'method': method,
       'body': body,
       'fields': fields,
-      'files': serializableFiles,
+      'files': serializableFiles, // Store paths instead of File objects
     };
     await _dbHelper.queueFailedRequest({
       'type': 'api',
@@ -86,8 +104,12 @@ class RetryService {
   Future<void> addFtpToQueue({
     required String localFilePath,
     required String remotePath,
+    required int ftpConfigId, // Added to specify which destination failed
   }) async {
-    final payload = {'localFilePath': localFilePath};
+    final payload = {
+      'localFilePath': localFilePath,
+      'ftpConfigId': ftpConfigId, // Store the specific config ID
+    };
     await _dbHelper.queueFailedRequest({
       'type': 'ftp',
       'endpoint_or_path': remotePath,
@@ -95,9 +117,10 @@ class RetryService {
       'timestamp': DateTime.now().toIso8601String(),
       'status': 'pending',
     });
-    debugPrint("FTP upload for file '$localFilePath' has been queued for retry.");
+    debugPrint("FTP upload for file '$localFilePath' to config ID $ftpConfigId has been queued for retry.");
   }
 
+
   /// Retrieves all tasks currently in the 'pending' state from the queue.
   Future<List<Map<String, dynamic>>> getPendingTasks() {
     return _dbHelper.getPendingRequests();
@@ -119,6 +142,7 @@ class RetryService {
       return;
     }
 
+    // Check internet connection *before* processing
     if (_authProvider == null || !await _authProvider!.isConnected()) {
       debugPrint("[RetryService] ❌ No internet connection. Aborting queue processing.");
       _isProcessing = false;
@@ -126,9 +150,15 @@ class RetryService {
     }
 
     debugPrint("[RetryService] 🔎 Found ${pendingTasks.length} pending tasks.");
+    // Process tasks one by one
     for (final task in pendingTasks) {
+      // Add safety check in case a task is deleted mid-processing by another call
+      if (await _dbHelper.getRequestById(task['id'] as int) != null) {
         await retryTask(task['id'] as int);
       }
+      // Optional: Add a small delay between tasks if needed
+      // await Future.delayed(Duration(seconds: 1));
+    }
 
     debugPrint("[RetryService] ⏹️ Finished processing retry queue.");
     _isProcessing = false;
@@ -139,28 +169,44 @@ class RetryService {
   Future<bool> retryTask(int taskId) async {
     final task = await _dbHelper.getRequestById(taskId);
     if (task == null) {
-      debugPrint("Retry failed: Task with ID $taskId not found in the queue.");
-      return false;
+      debugPrint("Retry failed: Task with ID $taskId not found in the queue (might have been processed already).");
+      return false; // Task doesn't exist or was processed elsewhere
     }
 
     bool success = false;
-    final payload = jsonDecode(task['payload'] as String);
+    Map<String, dynamic> payload; // Declare outside try-catch
+    final String taskType = task['type'] as String; // Get type early for logging
 
     try {
+      payload = jsonDecode(task['payload'] as String); // Decode payload inside try
+    } catch (e) {
+      debugPrint("Error decoding payload for task $taskId (Type: $taskType): $e. Removing invalid task.");
+      await _dbHelper.deleteRequestFromQueue(taskId);
+      return false; // Cannot process without valid payload
+    }
+
+
+    try {
+      // Ensure AuthProvider is initialized and we are online (checked in processRetryQueue)
       if (_authProvider == null) {
-        debugPrint("RetryService has not been initialized. Cannot process task.");
+        debugPrint("RetryService has not been initialized. Cannot process task $taskId.");
         return false;
       }
 
-      if (task['type'] == 'insitu_submission') {
+      // --- Complex Task Handlers ---
+      if (taskType == 'insitu_submission') {
         debugPrint("Retrying complex task 'insitu_submission' with ID $taskId.");
-        if (_marineInSituService == null) return false;
+        if (_marineInSituService == null) {
+          debugPrint("Retry failed: MarineInSituSamplingService not initialized.");
+          return false;
+        }
 
-        final String logFilePath = payload['localLogPath'];
-        final file = File(logFilePath);
+        final String logDirectoryPath = payload['localLogPath']; // Path to the directory
+        final jsonFilePath = p.join(logDirectoryPath, 'data.json');
+        final file = File(jsonFilePath);
 
         if (!await file.exists()) {
-          debugPrint("Retry failed: Source log file no longer exists at $logFilePath");
+          debugPrint("Retry failed: Source log file no longer exists at $jsonFilePath");
           await _dbHelper.deleteRequestFromQueue(taskId); // Remove invalid task
           return false;
         }
@@ -168,34 +214,37 @@ class RetryService {
         final content = await file.readAsString();
         final jsonData = jsonDecode(content) as Map<String, dynamic>;
         final InSituSamplingData dataToResubmit = InSituSamplingData.fromJson(jsonData);
-        final String logDirectoryPath = p.dirname(logFilePath);
 
+        // Re-run the original submission logic, passing the log directory
         final result = await _marineInSituService!.submitInSituSample(
           data: dataToResubmit,
-          appSettings: _authProvider!.appSettings,
+          appSettings: _authProvider!.appSettings, // Get current settings
           authProvider: _authProvider!,
-          logDirectory: logDirectoryPath,
+          logDirectory: logDirectoryPath, // Pass directory to update log
         );
         success = result['success'];
 
-        // --- START: ADDED LOGIC FOR RIVER IN-SITU SUBMISSION ---
-      } else if (task['type'] == 'river_insitu_submission') {
+      } else if (taskType == 'river_insitu_submission') {
         debugPrint("Retrying complex task 'river_insitu_submission' with ID $taskId.");
-        if (_riverInSituService == null) return false;
-
-        final String logFilePath = payload['localLogPath'];
-        final file = File(logFilePath);
-
-        if (!await file.exists()) {
-          debugPrint("Retry failed: Source log file no longer exists at $logFilePath");
-          await _dbHelper.deleteRequestFromQueue(taskId); // Remove invalid task
+        if (_riverInSituService == null) {
+          debugPrint("Retry failed: RiverInSituSamplingService not initialized.");
           return false;
         }
 
+        final String jsonFilePath = payload['localLogPath']; // Path to the JSON file
+        final file = File(jsonFilePath);
+
+        if (!await file.exists()) {
+          debugPrint("Retry failed: Source log file no longer exists at $jsonFilePath");
+          await _dbHelper.deleteRequestFromQueue(taskId);
+          return false;
+        }
+        final String logDirectoryPath = p.dirname(jsonFilePath); // Get directory from file path
+
+
         final content = await file.readAsString();
         final jsonData = jsonDecode(content) as Map<String, dynamic>;
         final RiverInSituSamplingData dataToResubmit = RiverInSituSamplingData.fromJson(jsonData);
-        final String logDirectoryPath = p.dirname(logFilePath);
 
         final result = await _riverInSituService!.submitData(
           data: dataToResubmit,
@@ -204,61 +253,292 @@ class RetryService {
           logDirectory: logDirectoryPath,
         );
         success = result['success'];
-        // --- END: ADDED LOGIC FOR RIVER IN-SITU SUBMISSION ---
 
-      } else if (task['type'] == 'api') {
+        // *** ADDED: Handler for river_investigative_submission ***
+      } else if (taskType == 'river_investigative_submission') {
+        debugPrint("Retrying complex task 'river_investigative_submission' with ID $taskId.");
+        if (_riverInvestigativeService == null) {
+          debugPrint("Retry failed: RiverInvestigativeSamplingService not initialized.");
+          return false;
+        }
+
+        final String jsonFilePath = payload['localLogPath']; // Path to the JSON file
+        final file = File(jsonFilePath);
+
+        if (!await file.exists()) {
+          debugPrint("Retry failed: Source log file no longer exists at $jsonFilePath");
+          await _dbHelper.deleteRequestFromQueue(taskId);
+          return false;
+        }
+        final String logDirectoryPath = p.dirname(jsonFilePath); // Get directory from file path
+
+        final content = await file.readAsString();
+        final jsonData = jsonDecode(content) as Map<String, dynamic>;
+        // Use the correct Investigative data model
+        final RiverInvesManualSamplingData dataToResubmit = RiverInvesManualSamplingData.fromJson(jsonData);
+
+        // Call the submitData method from the Investigative service
+        final result = await _riverInvestigativeService!.submitData(
+          data: dataToResubmit,
+          appSettings: _authProvider!.appSettings,
+          authProvider: _authProvider!,
+          logDirectory: logDirectoryPath,
+        );
+        success = result['success'];
+        // *** END ADDED ***
+
+      } else if (taskType == 'investigative_submission') {
+        debugPrint("Retrying complex task 'investigative_submission' with ID $taskId.");
+        if (_marineInvestigativeService == null) {
+          debugPrint("Retry failed: MarineInvestigativeSamplingService not initialized.");
+          return false;
+        }
+
+        final String logDirectoryPath = payload['localLogPath']; // Path to the directory
+        final jsonFilePath = p.join(logDirectoryPath, 'data.json');
+        final file = File(jsonFilePath);
+
+        if (!await file.exists()) {
+          debugPrint("Retry failed: Source log file no longer exists at $jsonFilePath");
+          await _dbHelper.deleteRequestFromQueue(taskId);
+          return false;
+        }
+
+        final content = await file.readAsString();
+        final jsonData = jsonDecode(content) as Map<String, dynamic>;
+        final MarineInvesManualSamplingData dataToResubmit = MarineInvesManualSamplingData.fromJson(jsonData);
+
+        final result = await _marineInvestigativeService!.submitInvestigativeSample(
+          data: dataToResubmit,
+          appSettings: _authProvider!.appSettings,
+          authProvider: _authProvider!,
+          logDirectory: logDirectoryPath,
+        );
+        success = result['success'];
+
+      } else if (taskType == 'tarball_submission') {
+        debugPrint("Retrying complex task 'tarball_submission' with ID $taskId.");
+        if (_marineTarballService == null) {
+          debugPrint("Retry failed: MarineTarballSamplingService not initialized.");
+          return false;
+        }
+
+        final String logDirectoryPath = payload['localLogPath']; // Path to the directory
+        final jsonFilePath = p.join(logDirectoryPath, 'data.json');
+        final file = File(jsonFilePath);
+
+        if (!await file.exists()) {
+          debugPrint("Retry failed: Source log file no longer exists at $jsonFilePath");
+          await _dbHelper.deleteRequestFromQueue(taskId);
+          return false;
+        }
+
+        final content = await file.readAsString();
+        final jsonData = jsonDecode(content) as Map<String, dynamic>;
+
+        // Recreate File objects from paths
+        File? fileFromJson(dynamic path) => (path is String && path.isNotEmpty) ? File(path) : null;
+
+        final TarballSamplingData dataToResubmit = TarballSamplingData()
+        // Reconstruct the object from JSON data
+          ..firstSampler = jsonData['firstSampler']
+          ..firstSamplerUserId = jsonData['firstSamplerUserId']
+          ..secondSampler = jsonData['secondSampler']
+          ..samplingDate = jsonData['samplingDate']
+          ..samplingTime = jsonData['samplingTime']
+          ..selectedStateName = jsonData['selectedStateName']
+          ..selectedCategoryName = jsonData['selectedCategoryName']
+          ..selectedStation = jsonData['selectedStation']
+          ..stationLatitude = jsonData['stationLatitude']
+          ..stationLongitude = jsonData['stationLongitude']
+          ..currentLatitude = jsonData['currentLatitude']
+          ..currentLongitude = jsonData['currentLongitude']
+          ..distanceDifference = jsonData['distanceDifference'] is num ? (jsonData['distanceDifference'] as num).toDouble() : null // Safe cast
+          ..distanceDifferenceRemarks = jsonData['distanceDifferenceRemarks']
+          ..classificationId = jsonData['classificationId'] is num ? (jsonData['classificationId'] as num).toInt() : null // Safe cast
+          ..selectedClassification = jsonData['selectedClassification']
+          ..leftCoastalViewImage = fileFromJson(jsonData['leftCoastalViewImage'])
+          ..rightCoastalViewImage = fileFromJson(jsonData['rightCoastalViewImage'])
+          ..verticalLinesImage = fileFromJson(jsonData['verticalLinesImage'])
+          ..horizontalLineImage = fileFromJson(jsonData['horizontalLineImage'])
+          ..optionalImage1 = fileFromJson(jsonData['optionalImage1'])
+          ..optionalRemark1 = jsonData['optionalRemark1']
+          ..optionalImage2 = fileFromJson(jsonData['optionalImage2'])
+          ..optionalRemark2 = jsonData['optionalRemark2']
+          ..optionalImage3 = fileFromJson(jsonData['optionalImage3'])
+          ..optionalRemark3 = jsonData['optionalRemark3']
+          ..optionalImage4 = fileFromJson(jsonData['optionalImage4'])
+          ..optionalRemark4 = jsonData['optionalRemark4']
+          ..reportId = jsonData['reportId'] // Preserve reportId if it exists
+          ..submissionStatus = jsonData['submissionStatus'] // Preserve status info
+          ..submissionMessage = jsonData['submissionMessage'];
+
+
+        debugPrint("Retrying Tarball submission...");
+        // Pass null for BuildContext, and the logDirectory path
+        final result = await _marineTarballService!.submitTarballSample(
+          data: dataToResubmit,
+          appSettings: _authProvider!.appSettings,
+          context: null, // Pass null for BuildContext during retry
+          logDirectory: logDirectoryPath, // Pass the directory path for potential update
+        );
+        success = result['success'];
+
+        // --- Simple Task Handlers ---
+      } else if (taskType == 'api') {
         final endpoint = task['endpoint_or_path'] as String;
         final method = payload['method'] as String;
-        final baseUrl = await _serverConfigService.getActiveApiUrl();
+        final baseUrl = await _serverConfigService.getActiveApiUrl(); // Get current active URL
         debugPrint("Retrying API task $taskId: $method to $baseUrl/$endpoint");
         Map<String, dynamic> result;
 
         if (method == 'POST_MULTIPART') {
           final Map<String, String> fields = Map<String, String>.from(payload['fields'] ?? {});
+          // Recreate File objects from paths stored in the payload
           final Map<String, File> files = (payload['files'] as Map<String, dynamic>?)
               ?.map((key, value) => MapEntry(key, File(value as String))) ?? {};
+
+          // Check if files still exist before attempting upload
+          bool allFilesExist = true;
+          List<String> missingFiles = []; // Keep track of missing files
+          for (var entry in files.entries) {
+            File file = entry.value;
+            if (!await file.exists()) {
+              debugPrint("Retry failed for API task $taskId: File ${file.path} (key: ${entry.key}) no longer exists.");
+              allFilesExist = false;
+              missingFiles.add(entry.key);
+              // break; // Stop checking further if one is missing
+            }
+          }
+
+          // If some files are missing, fail the entire task.
+          if (!allFilesExist) {
+            debugPrint("API Multipart retry failed for task $taskId because files are missing: ${missingFiles.join(', ')}. Removing task.");
+            await _dbHelper.deleteRequestFromQueue(taskId); // Remove invalid task
+            return false;
+          }
+
           result = await _baseApiService.postMultipart(baseUrl: baseUrl, endpoint: endpoint, fields: fields, files: files);
-        } else {
+        } else { // Standard POST
           final Map<String, dynamic> body = Map<String, dynamic>.from(payload['body'] ?? {});
           result = await _baseApiService.post(baseUrl, endpoint, body);
         }
         success = result['success'];
 
-      } else if (task['type'] == 'ftp') {
+      } else if (taskType == 'ftp') {
         final remotePath = task['endpoint_or_path'] as String;
         final localFile = File(payload['localFilePath'] as String);
-        debugPrint("Retrying FTP task $taskId: Uploading ${localFile.path} to $remotePath");
+        final int? ftpConfigId = payload['ftpConfigId'] as int?;
+
+        debugPrint("Retrying FTP task $taskId: Uploading ${localFile.path} to $remotePath using config ID $ftpConfigId");
+
+        if (ftpConfigId == null) {
+          debugPrint("Retry failed for FTP task $taskId: Missing FTP configuration ID in payload.");
+          await _dbHelper.deleteRequestFromQueue(taskId); // Remove invalid task
+          return false;
+        }
 
         if (await localFile.exists()) {
           final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
-          if (ftpConfigs.isEmpty) {
-            debugPrint("Retry failed for FTP task $taskId: No FTP configurations found.");
-            return false;
-          }
-          for (final config in ftpConfigs) {
-            final result = await _ftpService.uploadFile(config: config, fileToUpload: localFile, remotePath: remotePath);
-            if (result['success']) {
-              success = true;
-              break;
-            }
-          }
-        } else {
-          debugPrint("Retry failed for FTP task $taskId: Source file no longer exists at ${localFile.path}");
-          success = false;
-        }
-      }
-    } catch (e) {
-      debugPrint("A critical error occurred while retrying task $taskId: $e");
-      success = false;
+          final config = ftpConfigs.firstWhere((c) => c['ftp_config_id'] == ftpConfigId, orElse: () => <String, dynamic>{}); // Use explicit type
+
+
+          if (config.isEmpty) {
+            debugPrint("Retry failed for FTP task $taskId: FTP configuration with ID $ftpConfigId not found.");
+            return false; // Fail the retry attempt, keep in queue
           }
 
-    if (success) {
-      debugPrint("Task $taskId completed successfully. Removing from queue.");
-      await _dbHelper.deleteRequestFromQueue(taskId);
+          // Attempt upload using the specific config
+          final result = await _ftpService.uploadFile(config: config, fileToUpload: localFile, remotePath: remotePath);
+          success = result['success'];
+
         } else {
-      debugPrint("Retry attempt for task $taskId failed. It will remain in the queue.");
+          debugPrint("Retry failed for FTP task $taskId: Source file no longer exists at ${localFile.path}");
+          await _dbHelper.deleteRequestFromQueue(taskId); // Remove task if file is gone
+          return false; // Explicitly return false as success is false
+        }
+      } else {
+        debugPrint("Unknown task type '$taskType' for task ID $taskId. Cannot retry. Removing task.");
+        await _dbHelper.deleteRequestFromQueue(taskId);
+      }
+
+    } on SessionExpiredException catch (e) {
+      debugPrint("Session expired during retry attempt for task $taskId (Type: $taskType): $e. Task remains in queue.");
+      success = false; // Session expiry during retry means failure for this attempt
+    } catch (e, stacktrace) { // Catch potential exceptions during processing
+      debugPrint("A critical error occurred while retrying task $taskId (Type: $taskType): $e");
+      debugPrint("Stacktrace: $stacktrace"); // Log stacktrace for detailed debugging
+      success = false; // Ensure success is false on exception
+    }
+
+    // Post-processing: Remove successful tasks from queue
+    if (success) {
+      debugPrint("Task $taskId (Type: $taskType) completed successfully. Removing from queue.");
+      await _dbHelper.deleteRequestFromQueue(taskId);
+      // If it was a complex task involving temporary ZIP files, attempt to delete them
+      if (taskType.endsWith('_submission') && payload['localLogPath'] != null) {
+        // Assume localLogPath points to the JSON file, get directory for cleanup
+        String pathToCheck = payload['localLogPath'];
+        // Check if it's a directory path already (for older marine insitu logs)
+        bool isDirectory = await Directory(pathToCheck).exists();
+        if (!isDirectory && pathToCheck.endsWith('.json')) {
+          pathToCheck = p.dirname(pathToCheck); // Get directory if it's a file path
+          isDirectory = true; // Now we are checking the directory
+        }
+        _cleanUpTemporaryZipFiles(pathToCheck, isDirectory: isDirectory);
+      }
+      // If it was an FTP task, attempt to delete the temporary ZIP file
+      if (taskType == 'ftp' && payload['localFilePath'] != null && (payload['localFilePath'] as String).endsWith('.zip')) {
+        _cleanUpTemporaryZipFiles(payload['localFilePath'], isDirectory: false);
+      }
+
+    } else {
+      debugPrint("Retry attempt for task $taskId (Type: $taskType) failed. It will remain in the queue.");
+      // Optional: Implement a retry limit here. If retries > X, mark task as 'failed' instead of 'pending'.
+      // e.g., await _dbHelper.updateTaskStatus(taskId, 'failed');
     }
 
     return success;
   }
+
+  /// Helper function to delete temporary zip files after successful retry.
+  void _cleanUpTemporaryZipFiles(String path, {required bool isDirectory}) async {
+    try {
+      if (isDirectory) {
+        final dir = Directory(path);
+        if (await dir.exists()) {
+          final filesInDir = dir.listSync();
+          for (var entity in filesInDir) {
+            // Delete only ZIP files within the log directory
+            if (entity is File && entity.path.endsWith('.zip')) {
+              debugPrint("Deleting temporary zip file from directory: ${entity.path}");
+              await entity.delete();
             }
+          }
+          // Optional: Delete the directory itself if now empty, ONLY if safe.
+          // Be cautious as data.json might still be needed or other files exist.
+          // if (await dir.listSync().isEmpty) {
+          //    await dir.delete();
+          //    debugPrint("Deleted empty log directory: ${dir.path}");
+          // }
+        } else {
+          debugPrint("Log directory not found for cleanup: $path");
+        }
+      } else {
+        // If it's a specific file path (like from FTP task)
+        final file = File(path);
+        if (await file.exists() && path.endsWith('.zip')) { // Ensure it's a zip file
+          debugPrint("Deleting temporary zip file: ${file.path}");
+          await file.delete();
+        } else if (!path.endsWith('.zip')) {
+          debugPrint("Skipping cleanup for non-zip file path: $path");
+        } else {
+          debugPrint("Temporary zip file not found for cleanup: $path");
+        }
+      }
+    } catch (e) {
+      debugPrint("Error cleaning up temporary zip file(s) for path $path: $e");
+    }
+  }
+
+} // End of RetryService class

lib/services/river_in_situ_sampling_service.dart

@@ -169,15 +169,20 @@ class RiverInSituSamplingService {
     const String moduleName = 'river_in_situ';
 
     final connectivityResult = await Connectivity().checkConnectivity();
-    bool isOnline = connectivityResult != ConnectivityResult.none;
+    bool isOnline = !connectivityResult.contains(ConnectivityResult.none);
     bool isOfflineSession = authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
 
     if (isOnline && isOfflineSession) {
       debugPrint("River In-Situ submission online during offline session. Attempting auto-relogin...");
+      try {
         final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
         if (transitionSuccess) {
           isOfflineSession = false;
         } else {
+          isOnline = false; // Auto-relogin failed, treat as offline
+        }
+      } on SessionExpiredException catch (_) {
+        debugPrint("Session expired during auto-relogin check. Treating as offline.");
         isOnline = false;
       }
     }
@@ -196,6 +201,7 @@ class RiverInSituSamplingService {
       return await _performOfflineQueuing(
         data: data,
         moduleName: moduleName,
+        logDirectory: logDirectory, // Pass for potential update
       );
     }
   }
@@ -215,25 +221,29 @@ class RiverInSituSamplingService {
     bool anyApiSuccess = false;
     Map<String, dynamic> apiDataResult = {};
     Map<String, dynamic> apiImageResult = {};
+    String finalMessage = '';
+    String finalStatus = '';
     bool isSessionKnownToBeExpired = false;
 
     try {
+      // 1. Submit Form Data
       apiDataResult = await _submissionApiService.submitPost(
         moduleName: moduleName,
-        endpoint: 'river/manual/sample',
+        endpoint: 'river/manual/sample', // Correct endpoint
         body: data.toApiFormData(),
       );
 
       if (apiDataResult['success'] == true) {
         anyApiSuccess = true;
-        data.reportId = apiDataResult['data']?['r_man_id']?.toString();
+        data.reportId = apiDataResult['data']?['r_man_id']?.toString(); // Correct ID key
 
         if (data.reportId != null) {
           if (finalImageFiles.isNotEmpty) {
+            // 2. Submit Images
             apiImageResult = await _submissionApiService.submitMultipart(
               moduleName: moduleName,
-              endpoint: 'river/manual/images',
-              fields: {'r_man_id': data.reportId!},
+              endpoint: 'river/manual/images', // Correct endpoint
+              fields: {'r_man_id': data.reportId!}, // Correct field key
               files: finalImageFiles,
             );
             if (apiImageResult['success'] != true) {
@@ -245,65 +255,98 @@ class RiverInSituSamplingService {
           apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
         }
       }
-    } on SessionExpiredException catch (_) {
-      debugPrint("API submission failed with SessionExpiredException. Attempting silent relogin...");
-      final bool reloginSuccess = await authProvider.attemptSilentRelogin();
+      // If apiDataResult['success'] is false, SubmissionApiService queued it.
 
-      if (reloginSuccess) {
-        debugPrint("Silent relogin successful. Retrying entire online submission process...");
-        return await _performOnlineSubmission(
-          data: data,
-          appSettings: appSettings,
-          moduleName: moduleName,
-          authProvider: authProvider,
-          logDirectory: logDirectory,
-        );
-      } else {
-        debugPrint("Silent relogin failed. API part will be queued, proceeding with FTP.");
+    } on SessionExpiredException catch (_) {
+      debugPrint("Online submission failed due to session expiry that could not be refreshed.");
       isSessionKnownToBeExpired = true;
       anyApiSuccess = false;
       apiDataResult = {'success': false, 'message': 'Session expired and re-login failed. API submission queued.'};
-        await _retryService.addApiToQueue(endpoint: 'river/manual/sample', method: 'POST', body: data.toApiFormData());
-      }
-    } on SocketException catch (e) {
-      final errorMessage = "API submission failed with network error: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
+      // Manually queue API calls
       await _retryService.addApiToQueue(endpoint: 'river/manual/sample', method: 'POST', body: data.toApiFormData());
       if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        // Also queue images if data call might have partially succeeded before expiry
         await _retryService.addApiToQueue(endpoint: 'river/manual/images', method: 'POST_MULTIPART', fields: {'r_man_id': data.reportId!}, files: finalImageFiles);
       }
-    } on TimeoutException catch (e) {
-      final errorMessage = "API submission timed out: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
-      await _retryService.addApiToQueue(endpoint: 'river/manual/sample', method: 'POST', body: data.toApiFormData());
     }
 
+    // 3. Submit FTP Files
     Map<String, dynamic> ftpResults = {'statuses': []};
     bool anyFtpSuccess = false;
+
+    if (isSessionKnownToBeExpired) {
+      debugPrint("Skipping FTP attempt due to known expired session. Manually queuing FTP tasks.");
+      final baseFileNameForQueue = _generateBaseFileName(data); // Use helper
+
+      // --- START FIX: Add ftpConfigId when queuing ---
+      // Get all potential FTP configs
+      final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
+
+      final dataZip = await _zippingService.createDataZip(
+        jsonDataMap: { // Use specific JSON structures for River In-Situ FTP
+          'db.json': data.toDbJson(),
+          'river_insitu_basic_form.json': data.toBasicFormJson(),
+          'river_sampling_reading.json': data.toReadingJson(),
+          'river_manual_info.json': data.toManualInfoJson(),
+        },
+        baseFileName: baseFileNameForQueue,
+        destinationDir: null,
+      );
+      if (dataZip != null) {
+        // Queue for each config separately
+        for (final config in ftpConfigs) {
+          final configId = config['ftp_config_id'];
+          if (configId != null) {
+            await _retryService.addFtpToQueue(
+                localFilePath: dataZip.path,
+                remotePath: '/${p.basename(dataZip.path)}',
+                ftpConfigId: configId // Provide the specific config ID
+            );
+          }
+        }
+      }
+
+      if (finalImageFiles.isNotEmpty) {
+        final imageZip = await _zippingService.createImageZip(
+          imageFiles: finalImageFiles.values.toList(),
+          baseFileName: baseFileNameForQueue,
+          destinationDir: null,
+        );
+        if (imageZip != null) {
+          // Queue for each config separately
+          for (final config in ftpConfigs) {
+            final configId = config['ftp_config_id'];
+            if (configId != null) {
+              await _retryService.addFtpToQueue(
+                  localFilePath: imageZip.path,
+                  remotePath: '/${p.basename(imageZip.path)}',
+                  ftpConfigId: configId // Provide the specific config ID
+              );
+            }
+          }
+        }
+      }
+      // --- END FIX ---
+      ftpResults = {'statuses': [{'status': 'Queued', 'message': 'FTP upload queued due to API session issue.', 'success': false}]};
+      anyFtpSuccess = false;
+    } else {
       try {
         ftpResults = await _generateAndUploadFtpFiles(data, finalImageFiles, serverName, moduleName);
         anyFtpSuccess = !(ftpResults['statuses'] as List).any((status) => status['success'] == false && status['status'] != 'Not Configured');
-    } on SocketException catch (e) {
-      debugPrint("FTP submission failed with network error: $e");
-      anyFtpSuccess = false;
-    } on TimeoutException catch (e) {
-      debugPrint("FTP submission timed out: $e");
+      } catch (e) {
+        debugPrint("Unexpected FTP submission error: $e");
         anyFtpSuccess = false;
       }
+    }
 
+    // 4. Determine Final Status
     final bool overallSuccess = anyApiSuccess || anyFtpSuccess;
-    String finalMessage;
-    String finalStatus;
 
     if (anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'Data submitted successfully to all destinations.';
       finalStatus = 'S4';
     } else if (anyApiSuccess && !anyFtpSuccess) {
-      finalMessage = 'Data sent to API, but some FTP uploads failed and were queued.';
+      finalMessage = 'Data sent to API, but some FTP uploads failed or were queued.';
       finalStatus = 'S3';
     } else if (!anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
@@ -313,6 +356,7 @@ class RiverInSituSamplingService {
       finalStatus = 'L1';
     }
 
+    // 5. Log Locally
     await _logAndSave(
       data: data,
       status: finalStatus,
@@ -323,10 +367,12 @@ class RiverInSituSamplingService {
       logDirectory: logDirectory,
     );
 
+    // 6. Send Alert
     if (overallSuccess) {
       _handleSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty, isSessionExpired: isSessionKnownToBeExpired);
     }
 
+    // Return consistent format
     return {
       'status': finalStatus,
       'success': overallSuccess,
@@ -335,9 +381,12 @@ class RiverInSituSamplingService {
     };
   }
 
+
+  /// Handles queuing the submission data when the device is offline.
   Future<Map<String, dynamic>> _performOfflineQueuing({
     required RiverInSituSamplingData data,
     required String moduleName,
+    String? logDirectory, // Added for potential update
   }) async {
     final serverConfig = await _serverConfigService.getActiveApiConfig();
     final serverName = serverConfig?['config_name'] as String? ?? 'Default';
@@ -345,45 +394,66 @@ class RiverInSituSamplingService {
     data.submissionStatus = 'L1';
     data.submissionMessage = 'Submission queued for later retry.';
 
-    final String? localLogPath = await _localStorageService.saveRiverInSituSamplingData(data, serverName: serverName);
+    String? savedLogPath = logDirectory; // Use existing path if provided
 
-    if (localLogPath == null) {
+    // Save/Update local log first
+    if (savedLogPath != null && savedLogPath.isNotEmpty) {
+      await _localStorageService.updateRiverInSituLog(data.toMap()..['logDirectory'] = savedLogPath);
+      debugPrint("Updated existing River In-Situ log for queuing: $savedLogPath");
+    } else {
+      savedLogPath = await _localStorageService.saveRiverInSituSamplingData(data, serverName: serverName);
+      debugPrint("Saved new River In-Situ log for queuing: $savedLogPath");
+    }
+
+    if (savedLogPath == null) {
       const message = "Failed to save submission to local device storage.";
-      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName);
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, logDirectory: logDirectory);
       return {'status': 'Error', 'success': false, 'message': message};
     }
 
     await _retryService.queueTask(
-      type: 'river_insitu_submission',
+      type: 'river_insitu_submission', // Correct type
       payload: {
         'module': moduleName,
-        'localLogPath': p.join(localLogPath, 'data.json'),
+        'localLogPath': p.join(savedLogPath, 'data.json'), // Point to the json file
         'serverConfig': serverConfig,
       },
     );
 
-    const successMessage = "Submission failed to send and has been queued for later retry.";
-    return {'status': 'Queued', 'success': true, 'message': successMessage};
+    const successMessage = "Device offline. Submission has been saved locally and queued for automatic retry when connection is restored.";
+    // Log final queued state to central DB
+    // await _logAndSave(data: data, status: 'Queued', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, logDirectory: savedLogPath);
+
+    return {'status': 'Queued', 'success': true, 'message': successMessage, 'reportId': null};
   }
 
-  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(RiverInSituSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+  /// Helper to generate the base filename for ZIP files.
+  String _generateBaseFileName(RiverInSituSamplingData data) {
     final stationCode = data.selectedStation?['sampling_station_code'] ?? 'UNKNOWN';
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
-    final baseFileName = "${stationCode}_$fileTimestamp";
+    return "${stationCode}_$fileTimestamp";
+  }
 
-    final Directory? logDirectory = await _localStorageService.getLogDirectory(
-      serverName: serverName,
-      module: 'river',
-      subModule: 'river_in_situ_sampling',
-    );
+  /// Generates data and image ZIP files and uploads them using SubmissionFtpService.
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(RiverInSituSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+    final baseFileName = _generateBaseFileName(data);
 
-    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
+    final Directory? logDirectory = await _localStorageService.getRiverInSituBaseDir(data.samplingType, serverName: serverName); // Use correct base dir getter
+
+    final folderName = data.reportId ?? baseFileName;
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, folderName)) : null;
     if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
       await localSubmissionDir.create(recursive: true);
     }
 
+    // Create and upload data ZIP (with multiple JSON files specific to River In-Situ)
     final dataZip = await _zippingService.createDataZip(
-      jsonDataMap: {'db.json': jsonEncode(data.toApiFormData())},
+      jsonDataMap: {
+        'db.json': data.toDbJson(),
+        'river_insitu_basic_form.json': data.toBasicFormJson(),
+        'river_sampling_reading.json': data.toReadingJson(),
+        'river_manual_info.json': data.toManualInfoJson(),
+      },
       baseFileName: baseFileName,
       destinationDir: localSubmissionDir,
     );
@@ -393,6 +463,7 @@ class RiverInSituSamplingService {
           moduleName: moduleName, fileToUpload: dataZip, remotePath: '/${p.basename(dataZip.path)}');
     }
 
+    // Create and upload image ZIP
     final imageZip = await _zippingService.createImageZip(
       imageFiles: imageFiles.values.toList(),
       baseFileName: baseFileName,
@@ -406,12 +477,13 @@ class RiverInSituSamplingService {
 
     return {
       'statuses': <Map<String, dynamic>>[
-        ...(ftpDataResult['statuses'] as List),
-        ...(ftpImageResult['statuses'] as List),
+        ...(ftpDataResult['statuses'] as List? ?? []), // Use null-aware spread
+        ...(ftpImageResult['statuses'] as List? ?? []), // Use null-aware spread
       ],
     };
   }
 
+  /// Saves or updates the local log file and saves a record to the central DB log.
   Future<void> _logAndSave({
     required RiverInSituSamplingData data,
     required String status,
@@ -423,47 +495,64 @@ class RiverInSituSamplingService {
   }) async {
     data.submissionStatus = status;
     data.submissionMessage = message;
+    final baseFileName = _generateBaseFileName(data); // Use helper
 
-    if (logDirectory != null) {
-      final Map<String, dynamic> updatedLogData = data.toMap();
-      updatedLogData['logDirectory'] = logDirectory;
-      updatedLogData['serverConfigName'] = serverName;
-      updatedLogData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
-      updatedLogData['ftp_status'] = jsonEncode(ftpStatuses);
+    // Prepare log data map using toMap()
+    final Map<String, dynamic> logMapData = data.toMap();
+    // Add submission metadata
+    logMapData['submissionStatus'] = status;
+    logMapData['submissionMessage'] = message;
+    logMapData['reportId'] = data.reportId;
+    logMapData['serverConfigName'] = serverName;
+    logMapData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
+    logMapData['ftp_status'] = jsonEncode(ftpStatuses);
 
-      final imageFilePaths = data.toApiImageFiles();
-      imageFilePaths.forEach((key, file) {
-        if (file != null) {
-          updatedLogData[key] = file.path;
-        }
-      });
-
-      await _localStorageService.updateRiverInSituLog(updatedLogData);
+    if (logDirectory != null && logDirectory.isNotEmpty) {
+      // Update existing log
+      logMapData['logDirectory'] = logDirectory; // Ensure logDirectory path is in the map
+      await _localStorageService.updateRiverInSituLog(logMapData);
     } else {
+      // Save new log
       await _localStorageService.saveRiverInSituSamplingData(data, serverName: serverName);
     }
 
+    // Save to central DB log
     final imagePaths = data.toApiImageFiles().values.whereType<File>().map((f) => f.path).toList();
-    final logData = {
-      'submission_id': data.reportId ?? DateTime.now().millisecondsSinceEpoch.toString(),
-      'module': 'river', 'type': data.samplingType ?? 'In-Situ', 'status': status,
-      'message': message, 'report_id': data.reportId, 'created_at': DateTime.now().toIso8601String(),
-      'form_data': jsonEncode(data.toMap()), 'image_data': jsonEncode(imagePaths),
-      'server_name': serverName, 'api_status': jsonEncode(apiResults), 'ftp_status': jsonEncode(ftpStatuses),
+    final centralLogData = {
+      'submission_id': data.reportId ?? baseFileName, // Use helper result
+      'module': 'river',
+      'type': data.samplingType ?? 'In-Situ', // Correct type
+      'status': status,
+      'message': message,
+      'report_id': data.reportId,
+      'created_at': DateTime.now().toIso8601String(),
+      'form_data': jsonEncode(logMapData), // Log the comprehensive map
+      'image_data': jsonEncode(imagePaths),
+      'server_name': serverName,
+      'api_status': jsonEncode(apiResults),
+      'ftp_status': jsonEncode(ftpStatuses),
     };
-    await _dbHelper.saveSubmissionLog(logData);
+    try {
+      await _dbHelper.saveSubmissionLog(centralLogData);
+    } catch (e) {
+      debugPrint("Error saving River In-Situ submission log to DB: $e");
+    }
   }
 
+
+  /// Handles sending or queuing the Telegram alert for River In-Situ submissions.
   Future<void> _handleSuccessAlert(RiverInSituSamplingData data, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly, bool isSessionExpired = false}) async {
     try {
-      final message = await _generateInSituAlertMessage(data, isDataOnly: isDataOnly);
+      final message = await _generateInSituAlertMessage(data, isDataOnly: isDataOnly); // Call local helper
+      final alertKey = 'river_in_situ'; // Correct key
+
       if (isSessionExpired) {
-        debugPrint("Session is expired; queuing Telegram alert directly.");
-        await _telegramService.queueMessage('river_in_situ', message, appSettings);
+        debugPrint("Session is expired; queuing Telegram alert directly for $alertKey.");
+        await _telegramService.queueMessage(alertKey, message, appSettings);
       } else {
-        final bool wasSent = await _telegramService.sendAlertImmediately('river_in_situ', message, appSettings);
+        final bool wasSent = await _telegramService.sendAlertImmediately(alertKey, message, appSettings);
         if (!wasSent) {
-          await _telegramService.queueMessage('river_in_situ', message, appSettings);
+          await _telegramService.queueMessage(alertKey, message, appSettings);
         }
       }
     } catch (e) {
@@ -471,6 +560,7 @@ class RiverInSituSamplingService {
     }
   }
 
+  /// Generates the specific Telegram alert message content for River In-Situ.
   Future<String> _generateInSituAlertMessage(RiverInSituSamplingData data, {required bool isDataOnly}) async {
     final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
     final stationName = data.selectedStation?['sampling_river'] ?? 'N/A';
@@ -491,7 +581,7 @@ class RiverInSituSamplingService {
       ..writeln('*Sonde ID:* $sondeID')
       ..writeln('*Status of Submission:* Successful');
 
-    if (distanceKm > 0 || (distanceRemarks.isNotEmpty && distanceRemarks != 'N/A')) {
+    if (distanceKm * 1000 > 50 || (distanceRemarks.isNotEmpty && distanceRemarks != 'N/A')) { // Check if distance > 50m
       buffer
         ..writeln()
         ..writeln('🔔 *Distance Alert:*')
@@ -500,6 +590,79 @@ class RiverInSituSamplingService {
         buffer.writeln('*Remarks for distance:* $distanceRemarks');
       }
     }
+
+    // Add parameter limit check section if needed
+    final outOfBoundsAlert = await _getOutOfBoundsAlertSection(data);
+    if (outOfBoundsAlert.isNotEmpty) {
+      buffer.write(outOfBoundsAlert);
+    }
+
+    return buffer.toString();
+  }
+
+  /// Helper to generate the parameter limit alert section for Telegram.
+  Future<String> _getOutOfBoundsAlertSection(RiverInSituSamplingData data) async {
+    // Define mapping from data model keys to parameter names used in limits table
+    const Map<String, String> _parameterKeyToLimitName = {
+      'oxygenConcentration': 'Oxygen Conc', 'oxygenSaturation': 'Oxygen Sat', 'ph': 'pH',
+      'salinity': 'Salinity', 'electricalConductivity': 'Conductivity', 'temperature': 'Temperature',
+      'tds': 'TDS', 'turbidity': 'Turbidity', 'ammonia': 'Ammonia', 'batteryVoltage': 'Battery',
+    };
+
+    final allLimits = await _dbHelper.loadRiverParameterLimits() ?? []; // Load river limits
+    if (allLimits.isEmpty) return "";
+
+    final readings = {
+      'oxygenConcentration': data.oxygenConcentration, 'oxygenSaturation': data.oxygenSaturation,
+      'ph': data.ph, 'salinity': data.salinity, 'electricalConductivity': data.electricalConductivity,
+      'temperature': data.temperature, 'tds': data.tds, 'turbidity': data.turbidity,
+      'ammonia': data.ammonia, 'batteryVoltage': data.batteryVoltage,
+    };
+
+    final List<String> outOfBoundsMessages = [];
+
+    double? parseLimitValue(dynamic value) {
+      if (value == null) return null;
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    readings.forEach((key, value) {
+      if (value == null || value == -999.0) return;
+
+      final limitName = _parameterKeyToLimitName[key];
+      if (limitName == null) return;
+
+      // Find the limit data for this parameter (river limits are not station-specific in the current DB structure)
+      final limitData = allLimits.firstWhere(
+            (l) => l['param_parameter_list'] == limitName,
+        orElse: () => <String, dynamic>{}, // Use explicit type
+      );
+
+      if (limitData.isNotEmpty) {
+        final lowerLimit = parseLimitValue(limitData['param_lower_limit']);
+        final upperLimit = parseLimitValue(limitData['param_upper_limit']);
+
+        if ((lowerLimit != null && value < lowerLimit) || (upperLimit != null && value > upperLimit)) {
+          final valueStr = value.toStringAsFixed(5);
+          final lowerStr = lowerLimit?.toStringAsFixed(5) ?? 'N/A';
+          final upperStr = upperLimit?.toStringAsFixed(5) ?? 'N/A';
+          outOfBoundsMessages.add('- *$limitName*: `$valueStr` (Limit: `$lowerStr` - `$upperStr`)');
+        }
+      }
+    });
+
+    if (outOfBoundsMessages.isEmpty) {
+      return "";
+    }
+
+    final buffer = StringBuffer()
+      ..writeln()
+      ..writeln('⚠️ *Parameter Limit Alert:*')
+      ..writeln('The following parameters were outside their defined limits:');
+    buffer.writeAll(outOfBoundsMessages, '\n');
+
     return buffer.toString();
   }
 }

lib/services/river_investigative_sampling_service.dart

@@ -0,0 +1,774 @@
+// lib/services/river_investigative_sampling_service.dart
+
+import 'dart:async';
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:image_picker/image_picker.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:path/path.dart' as p;
+import 'package:image/image.dart' as img;
+import 'package:geolocator/geolocator.dart';
+import 'package:permission_handler/permission_handler.dart';
+import 'package:flutter_bluetooth_serial/flutter_bluetooth_serial.dart';
+import 'package:usb_serial/usb_serial.dart';
+import 'dart:convert';
+import 'package:intl/intl.dart';
+import 'package:connectivity_plus/connectivity_plus.dart';
+import 'package:provider/provider.dart'; // Keep provider import if needed internally, though less common in services
+
+import '../auth_provider.dart';
+import 'location_service.dart';
+import '../models/river_inves_manual_sampling_data.dart'; // Use Investigative model
+import '../bluetooth/bluetooth_manager.dart';
+import '../serial/serial_manager.dart';
+import 'api_service.dart'; // Keep ApiService import for DatabaseHelper access within service if needed, or remove if unused directly
+import 'local_storage_service.dart';
+import 'server_config_service.dart';
+import 'zipping_service.dart';
+import 'submission_api_service.dart';
+import 'submission_ftp_service.dart';
+import 'telegram_service.dart';
+import 'retry_service.dart';
+import 'base_api_service.dart'; // Import for SessionExpiredException
+
+
+class RiverInvestigativeSamplingService { // Renamed class
+  final LocationService _locationService = LocationService();
+  final BluetoothManager _bluetoothManager = BluetoothManager();
+  final SerialManager _serialManager = SerialManager();
+  final SubmissionApiService _submissionApiService = SubmissionApiService();
+  final SubmissionFtpService _submissionFtpService = SubmissionFtpService();
+  final DatabaseHelper _dbHelper = DatabaseHelper();
+  final LocalStorageService _localStorageService = LocalStorageService();
+  final ServerConfigService _serverConfigService = ServerConfigService();
+  final ZippingService _zippingService = ZippingService();
+  final RetryService _retryService = RetryService();
+  final TelegramService _telegramService;
+  final ImagePicker _picker = ImagePicker();
+
+  static const platform = MethodChannel('com.example.environment_monitoring_app/usb');
+
+  RiverInvestigativeSamplingService(this._telegramService); // Constructor remains similar
+
+  Future<Position> getCurrentLocation() => _locationService.getCurrentLocation();
+  double calculateDistance(double lat1, double lon1, double lat2, double lon2) => _locationService.calculateDistance(lat1, lon1, lat2, lon2);
+
+  // Adapted image processing for Investigative data
+  Future<File?> pickAndProcessImage(ImageSource source, { required RiverInvesManualSamplingData data, required String imageInfo, bool isRequired = false, String? stationCode}) async { // Updated model type
+    try {
+      final XFile? pickedFile = await _picker.pickImage(
+        source: source,
+        imageQuality: 85, // Keep quality settings
+        maxWidth: 1024,   // Keep resolution settings
+      );
+
+      if (pickedFile == null) {
+        return null;
+      }
+
+      final bytes = await pickedFile.readAsBytes();
+      img.Image? originalImage = img.decodeImage(bytes);
+      if (originalImage == null) {
+        return null;
+      }
+
+      // Keep landscape requirement for required photos
+      if (isRequired && originalImage.height > originalImage.width) {
+        debugPrint("Image rejected: Must be in landscape orientation.");
+        return null;
+      }
+
+      // Watermark using investigative data
+      final String watermarkTimestamp = "${data.samplingDate} ${data.samplingTime}";
+      final font = img.arial24; // Use consistent font
+      final textWidth = watermarkTimestamp.length * 12; // Approximate width
+      // Draw background rectangle for text visibility
+      img.fillRect(originalImage, x1: 5, y1: 5, x2: textWidth + 15, y2: 35, color: img.ColorRgb8(255, 255, 255));
+      // Draw timestamp string
+      img.drawString(originalImage, watermarkTimestamp, font: font, x: 10, y: 10, color: img.ColorRgb8(0, 0, 0));
+
+      final tempDir = await getTemporaryDirectory();
+      // Use the determined station code passed in (handles Manual/Triennial/New)
+      final finalStationCode = stationCode ?? 'NA';
+      final fileTimestamp = "${data.samplingDate}-${data.samplingTime}".replaceAll(':', '-');
+      // Consistent filename format
+      final newFileName = "${finalStationCode}_${fileTimestamp}_${imageInfo.replaceAll(' ', '')}.jpg";
+      final filePath = p.join(tempDir.path, newFileName);
+
+      // Encode and write the processed image
+      return File(filePath)..writeAsBytesSync(img.encodeJpg(originalImage));
+
+    } catch (e) {
+      debugPrint('Error in pickAndProcessImage (River Investigative): $e');
+      return null;
+    }
+  }
+
+  // Bluetooth and Serial Management - No changes needed, uses shared managers
+  ValueNotifier<BluetoothConnectionState> get bluetoothConnectionState => _bluetoothManager.connectionState;
+  ValueNotifier<SerialConnectionState> get serialConnectionState => _serialManager.connectionState;
+
+  ValueNotifier<String?> get sondeId {
+    if (_bluetoothManager.connectionState.value != BluetoothConnectionState.disconnected) {
+      return _bluetoothManager.sondeId;
+    }
+    return _serialManager.sondeId;
+  }
+
+  Stream<Map<String, double>> get bluetoothDataStream => _bluetoothManager.dataStream;
+  Stream<Map<String, double>> get serialDataStream => _serialManager.dataStream;
+  String? get connectedBluetoothDeviceName => _bluetoothManager.connectedDeviceName.value;
+  String? get connectedSerialDeviceName => _serialManager.connectedDeviceName.value;
+
+  Future<bool> requestDevicePermissions() async {
+    // Permission logic remains the same
+    Map<Permission, PermissionStatus> statuses = await [
+      Permission.bluetoothScan,
+      Permission.bluetoothConnect,
+      Permission.locationWhenInUse, // Keep location permission for GPS
+    ].request();
+
+    if (statuses[Permission.bluetoothScan] == PermissionStatus.granted &&
+        statuses[Permission.bluetoothConnect] == PermissionStatus.granted &&
+        statuses[Permission.locationWhenInUse] == PermissionStatus.granted) { // Ensure location is granted too
+      return true;
+    } else {
+      debugPrint("Bluetooth Scan: ${statuses[Permission.bluetoothScan]}, Bluetooth Connect: ${statuses[Permission.bluetoothConnect]}, Location: ${statuses[Permission.locationWhenInUse]}");
+      return false;
+    }
+  }
+
+  Future<List<BluetoothDevice>> getPairedBluetoothDevices() => _bluetoothManager.getPairedDevices();
+  Future<void> connectToBluetoothDevice(BluetoothDevice device) => _bluetoothManager.connect(device);
+  void disconnectFromBluetooth() => _bluetoothManager.disconnect();
+  void startBluetoothAutoReading({Duration? interval}) => _bluetoothManager.startAutoReading(interval: interval ?? const Duration(seconds: 2));
+  void stopBluetoothAutoReading() => _bluetoothManager.stopAutoReading();
+  Future<List<UsbDevice>> getAvailableSerialDevices() => _serialManager.getAvailableDevices();
+
+  Future<bool> requestUsbPermission(UsbDevice device) async {
+    // USB permission logic remains the same
+    try {
+      // Ensure the platform channel name matches what's defined in your native code (Android/iOS)
+      return await platform.invokeMethod('requestUsbPermission', {'vid': device.vid, 'pid': device.pid}) ?? false;
+    } on PlatformException catch (e) {
+      debugPrint("Failed to request USB permission: '${e.message}'.");
+      return false;
+    }
+  }
+
+  Future<void> connectToSerialDevice(UsbDevice device) async {
+    // Serial connection logic remains the same
+    final bool permissionGranted = await requestUsbPermission(device);
+    if (permissionGranted) {
+      await _serialManager.connect(device);
+    } else {
+      throw Exception("USB permission was not granted.");
+    }
+  }
+
+  void disconnectFromSerial() => _serialManager.disconnect();
+  void startSerialAutoReading({Duration? interval}) => _serialManager.startAutoReading(interval: interval ?? const Duration(seconds: 2));
+  void stopSerialAutoReading() => _serialManager.stopAutoReading();
+  void dispose() {
+    _bluetoothManager.dispose();
+    _serialManager.dispose();
+  }
+
+  // Adapted Submission Logic for Investigative
+  Future<Map<String, dynamic>> submitData({
+    required RiverInvesManualSamplingData data, // Updated model type
+    required List<Map<String, dynamic>>? appSettings,
+    required AuthProvider authProvider,
+    String? logDirectory,
+  }) async {
+    // *** MODIFIED: Module name changed ***
+    const String moduleName = 'river_investigative';
+
+    final connectivityResult = await Connectivity().checkConnectivity();
+    bool isOnline = !connectivityResult.contains(ConnectivityResult.none);
+    bool isOfflineSession = authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
+
+    // Auto-relogin logic remains the same
+    if (isOnline && isOfflineSession) {
+      debugPrint("River Investigative submission online during offline session. Attempting auto-relogin..."); // Log context update
+      try {
+        final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
+        if (transitionSuccess) {
+          isOfflineSession = false; // Successfully transitioned to online
+        } else {
+          isOnline = false; // Auto-relogin failed, treat as offline
+        }
+      } on SessionExpiredException catch (_) {
+        debugPrint("Session expired during auto-relogin check. Treating as offline.");
+        isOnline = false;
+      }
+    }
+
+    // Branch based on connectivity and session status
+    if (isOnline && !isOfflineSession) {
+      debugPrint("Proceeding with direct ONLINE River Investigative submission..."); // Log context update
+      return await _performOnlineSubmission(
+        data: data,
+        appSettings: appSettings,
+        moduleName: moduleName,
+        authProvider: authProvider,
+        logDirectory: logDirectory,
+      );
+    } else {
+      debugPrint("Proceeding with OFFLINE River Investigative queuing mechanism..."); // Log context update
+      return await _performOfflineQueuing(
+        data: data,
+        moduleName: moduleName,
+        logDirectory: logDirectory, // Pass for potential update
+      );
+    }
+  }
+
+  Future<Map<String, dynamic>> _performOnlineSubmission({
+    required RiverInvesManualSamplingData data, // Updated model type
+    required List<Map<String, dynamic>>? appSettings,
+    required String moduleName, // Passed in as 'river_investigative'
+    required AuthProvider authProvider,
+    String? logDirectory,
+  }) async {
+    final serverName = (await _serverConfigService.getActiveApiConfig())?['config_name'] as String? ?? 'Default';
+    // Get image files using the Investigative model's method
+    final imageFilesWithNulls = data.toApiImageFiles();
+    imageFilesWithNulls.removeWhere((key, value) => value == null); // Remove nulls
+    final Map<String, File> finalImageFiles = imageFilesWithNulls.cast<String, File>();
+
+    bool anyApiSuccess = false;
+    Map<String, dynamic> apiDataResult = {};
+    Map<String, dynamic> apiImageResult = {};
+    String finalMessage = '';
+    String finalStatus = '';
+    bool isSessionKnownToBeExpired = false;
+
+    try {
+      // 1. Submit Form Data (using Investigative endpoint and data)
+      apiDataResult = await _submissionApiService.submitPost(
+        moduleName: moduleName, // 'river_investigative'
+        // *** MODIFIED: API Endpoint ***
+        endpoint: 'river/investigative/sample', // Assumed endpoint for investigative data
+        body: data.toApiFormData(), // Use Investigative model's method
+      );
+
+      if (apiDataResult['success'] == true) {
+        anyApiSuccess = true;
+        // *** MODIFIED: Extract report ID using assumed key ***
+        data.reportId = apiDataResult['data']?['r_inv_id']?.toString(); // Assumed key for investigative ID
+
+        if (data.reportId != null) {
+          if (finalImageFiles.isNotEmpty) {
+            // 2. Submit Images (using Investigative endpoint)
+            apiImageResult = await _submissionApiService.submitMultipart(
+              moduleName: moduleName, // 'river_investigative'
+              // *** MODIFIED: API Endpoint ***
+              endpoint: 'river/investigative/images', // Assumed endpoint for investigative images
+              // *** MODIFIED: Field key for ID ***
+              fields: {'r_inv_id': data.reportId!}, // Use assumed investigative ID key
+              files: finalImageFiles,
+            );
+            if (apiImageResult['success'] != true) {
+              // If image upload fails after data success, mark API part as failed overall for simplicity, or handle partially.
+              anyApiSuccess = false; // Treat as overall API failure if images fail
+            }
+          }
+          // If no images, data submission success is enough
+        } else {
+          // API succeeded but didn't return an ID - treat as failure
+          anyApiSuccess = false;
+          apiDataResult['success'] = false; // Mark as failed
+          apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
+        }
+      }
+      // If apiDataResult['success'] is false initially, SubmissionApiService queued it.
+
+    } on SessionExpiredException catch (_) {
+      debugPrint("Online River Investigative submission failed due to session expiry that could not be refreshed."); // Log context update
+      isSessionKnownToBeExpired = true;
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': 'Session expired and re-login failed. API submission queued.'};
+      // Manually queue API calls if session expired during attempt
+      // *** MODIFIED: Use Investigative endpoints for queueing ***
+      await _retryService.addApiToQueue(endpoint: 'river/investigative/sample', method: 'POST', body: data.toApiFormData());
+      if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        // Queue images only if we might have gotten an ID before expiry
+        await _retryService.addApiToQueue(endpoint: 'river/investigative/images', method: 'POST_MULTIPART', fields: {'r_inv_id': data.reportId!}, files: finalImageFiles);
+      } else if (finalImageFiles.isNotEmpty && data.reportId == null) {
+        // If data call failed before getting ID, queue images without ID - might need manual linking later or separate retry logic
+        debugPrint("Queueing investigative images without report ID due to session expiry during data submission.");
+        // How to handle this depends on backend capabilities or manual intervention needs.
+        // Option: Queue a complex task instead? For now, queueing individually.
+        await _retryService.addApiToQueue(endpoint: 'river/investigative/images', method: 'POST_MULTIPART', fields: {}, files: finalImageFiles); // Queue images without ID
+      }
+    }
+
+    // 3. Submit FTP Files (Logic remains similar, uses specific JSON methods)
+    Map<String, dynamic> ftpResults = {'statuses': []};
+    bool anyFtpSuccess = false;
+
+    if (isSessionKnownToBeExpired) {
+      debugPrint("Skipping FTP attempt for River Investigative due to known expired session. Manually queuing FTP tasks."); // Log context update
+      final baseFileNameForQueue = _generateBaseFileName(data); // Use helper
+
+      // --- START FIX: Add ftpConfigId when queuing --- (Copied from In-Situ, ensure DB structure matches)
+      final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
+
+      final dataZip = await _zippingService.createDataZip(
+        jsonDataMap: { // Use specific JSON structures for River Investigative FTP
+          'db.json': data.toDbJson(), // Use Investigative model's method
+          'river_inves_basic_form.json': data.toBasicFormJson(), // Use Investigative model's method
+          'river_inves_reading.json': data.toReadingJson(), // Use Investigative model's method
+          'river_inves_manual_info.json': data.toManualInfoJson(), // Use Investigative model's method
+        },
+        baseFileName: baseFileNameForQueue,
+        destinationDir: null, // Save to temp dir
+      );
+      if (dataZip != null) {
+        // Queue for each config separately
+        for (final config in ftpConfigs) {
+          final configId = config['ftp_config_id'];
+          if (configId != null) {
+            await _retryService.addFtpToQueue(
+                localFilePath: dataZip.path,
+                remotePath: '/${p.basename(dataZip.path)}', // Standard remote path
+                ftpConfigId: configId // Provide the specific config ID
+            );
+          }
+        }
+      }
+
+      if (finalImageFiles.isNotEmpty) {
+        final imageZip = await _zippingService.createImageZip(
+          imageFiles: finalImageFiles.values.toList(),
+          baseFileName: baseFileNameForQueue,
+          destinationDir: null, // Save to temp dir
+        );
+        if (imageZip != null) {
+          // Queue for each config separately
+          for (final config in ftpConfigs) {
+            final configId = config['ftp_config_id'];
+            if (configId != null) {
+              await _retryService.addFtpToQueue(
+                  localFilePath: imageZip.path,
+                  remotePath: '/${p.basename(imageZip.path)}', // Standard remote path
+                  ftpConfigId: configId // Provide the specific config ID
+              );
+            }
+          }
+        }
+      }
+      // --- END FIX ---
+      ftpResults = {'statuses': [{'status': 'Queued', 'message': 'FTP upload queued due to API session issue.', 'success': false}]};
+      anyFtpSuccess = false; // Mark FTP as unsuccessful for overall status determination
+    } else {
+      // Proceed with FTP attempt if session is okay
+      try {
+        ftpResults = await _generateAndUploadFtpFiles(data, finalImageFiles, serverName, moduleName); // Call helper
+        // Determine success based on statuses (excluding 'Not Configured')
+        anyFtpSuccess = !(ftpResults['statuses'] as List).any((status) => status['success'] == false && status['status'] != 'Not Configured');
+      } catch (e) {
+        debugPrint("Unexpected River Investigative FTP submission error: $e"); // Log context update
+        anyFtpSuccess = false; // Mark FTP as failed on error
+        ftpResults = {'statuses': [{'status': 'Error', 'message': 'FTP process failed: $e.', 'success': false}]}; // Provide error status
+      }
+    }
+
+    // 4. Determine Final Status (Logic remains the same)
+    final bool overallSuccess = anyApiSuccess || anyFtpSuccess;
+
+    if (anyApiSuccess && anyFtpSuccess) {
+      finalMessage = 'Data submitted successfully to all destinations.';
+      finalStatus = 'S4'; // API OK, FTP OK
+    } else if (anyApiSuccess && !anyFtpSuccess) {
+      finalMessage = 'Data sent to API, but some FTP uploads failed or were queued.';
+      finalStatus = 'S3'; // API OK, FTP Failed/Queued
+    } else if (!anyApiSuccess && anyFtpSuccess) {
+      finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
+      finalStatus = 'L4'; // API Failed/Queued, FTP OK
+    } else { // Neither API nor FTP fully succeeded without queueing/errors
+      finalMessage = apiDataResult['message'] ?? 'All submission attempts failed and have been queued for retry.';
+      finalStatus = 'L1'; // API Failed/Queued, FTP Failed/Queued
+    }
+
+    // 5. Log Locally (using Investigative log method)
+    await _logAndSave(
+      data: data,
+      status: finalStatus,
+      message: finalMessage,
+      apiResults: [apiDataResult, apiImageResult].where((r) => r.isNotEmpty).toList(), // Filter out empty results
+      ftpStatuses: ftpResults['statuses'] ?? [],
+      serverName: serverName,
+      logDirectory: logDirectory,
+    );
+
+    // 6. Send Alert (using Investigative alert method)
+    if (overallSuccess) { // Send alert only if at least one part (API or FTP) succeeded without errors/queueing immediately
+      _handleSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty, isSessionExpired: isSessionKnownToBeExpired);
+    }
+
+    // Return consistent result format
+    return {
+      'status': finalStatus,
+      'success': overallSuccess, // Reflects if *any* part succeeded now
+      'message': finalMessage,
+      'reportId': data.reportId // May be null if API failed
+    };
+  }
+
+
+  /// Handles queuing the submission data when the device is offline for Investigative.
+  Future<Map<String, dynamic>> _performOfflineQueuing({
+    required RiverInvesManualSamplingData data, // Updated model type
+    required String moduleName, // Passed in as 'river_investigative'
+    String? logDirectory, // Added for potential update
+  }) async {
+    final serverConfig = await _serverConfigService.getActiveApiConfig();
+    final serverName = serverConfig?['config_name'] as String? ?? 'Default';
+
+    data.submissionStatus = 'Queued'; // Tentative status, will be L1 after saving
+    data.submissionMessage = 'Submission queued for later retry.';
+
+    String? savedLogPath = logDirectory; // Use existing path if provided for an update
+
+    // Save/Update local log first using the specific Investigative save method
+    if (savedLogPath != null && savedLogPath.isNotEmpty) {
+      // *** MODIFIED: Use correct update method ***
+      await _localStorageService.updateRiverInvestigativeLog(data.toMap()..['logDirectory'] = savedLogPath); // Add path for update method
+      debugPrint("Updated existing River Investigative log for queuing: $savedLogPath"); // Log context update
+    } else {
+      // *** MODIFIED: Use correct save method ***
+      savedLogPath = await _localStorageService.saveRiverInvestigativeSamplingData(data, serverName: serverName);
+      debugPrint("Saved new River Investigative log for queuing: $savedLogPath"); // Log context update
+    }
+
+    if (savedLogPath == null) {
+      // If saving the log itself failed
+      const message = "Failed to save River Investigative submission to local device storage."; // Log context update
+      // Log failure to central DB log if possible
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, logDirectory: logDirectory);
+      return {'status': 'Error', 'success': false, 'message': message};
+    }
+
+    // Queue the task for the RetryService
+    // *** MODIFIED: Use specific task type ***
+    await _retryService.queueTask(
+      type: 'river_investigative_submission', // Specific type for retry handler
+      payload: {
+        'module': moduleName, // 'river_investigative'
+        'localLogPath': p.join(savedLogPath, 'data.json'), // Point to the json file within the saved directory
+        'serverConfig': serverConfig, // Pass current server config at time of queueing
+      },
+    );
+
+    const successMessage = "Device offline. River Investigative submission has been saved locally and queued for automatic retry when connection is restored."; // Log context update
+    // Update final status in the data object and potentially update log again, or just log to central DB
+    data.submissionStatus = 'L1'; // Final queued status
+    data.submissionMessage = successMessage;
+    // Log final queued state to central DB log
+    await _logAndSave(data: data, status: 'L1', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, logDirectory: savedLogPath); // Ensure log reflects final state
+
+    return {'status': 'Queued', 'success': true, 'message': successMessage, 'reportId': null};
+  }
+
+  /// Helper to generate the base filename for ZIP files (Investigative).
+  String _generateBaseFileName(RiverInvesManualSamplingData data) { // Updated model type
+    // Use the determined station code helper
+    final stationCode = data.getDeterminedStationCode() ?? 'UNKNOWN';
+    final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
+    return "${stationCode}_$fileTimestamp"; // Consistent format
+  }
+
+  /// Generates data and image ZIP files and uploads them using SubmissionFtpService (Investigative).
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(RiverInvesManualSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async { // Updated model type
+    final baseFileName = _generateBaseFileName(data); // Use helper
+
+    // *** MODIFIED: Use correct base dir getter ***
+    final Directory? logDirectory = await _localStorageService.getRiverInvestigativeBaseDir(serverName: serverName); // NEW GETTER
+
+    // Determine the specific folder for this submission log within the base directory
+    final folderName = data.reportId ?? baseFileName; // Use report ID if available, else generated name
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, folderName)) : null;
+    if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
+      await localSubmissionDir.create(recursive: true); // Create if doesn't exist
+    }
+
+    // Create and upload data ZIP (with multiple JSON files specific to River Investigative)
+    final dataZip = await _zippingService.createDataZip(
+      jsonDataMap: {
+        // *** MODIFIED: Use Investigative model's JSON methods and filenames ***
+        'db.json': jsonEncode(data.toDbJson()), // Main data structure
+        'river_inves_basic_form.json': data.toBasicFormJson(),
+        'river_inves_reading.json': data.toReadingJson(),
+        'river_inves_manual_info.json': data.toManualInfoJson(),
+      },
+      baseFileName: baseFileName,
+      destinationDir: localSubmissionDir, // Save ZIP in the specific log folder
+    );
+    Map<String, dynamic> ftpDataResult = {'success': true, 'statuses': []}; // Default success if no file
+    if (dataZip != null) {
+      ftpDataResult = await _submissionFtpService.submit(
+          moduleName: moduleName, // 'river_investigative'
+          fileToUpload: dataZip,
+          remotePath: '/${p.basename(dataZip.path)}' // Standard remote path
+      );
+    }
+
+    // Create and upload image ZIP (if images exist)
+    Map<String, dynamic> ftpImageResult = {'success': true, 'statuses': []}; // Default success if no images
+    if (imageFiles.isNotEmpty) {
+      final imageZip = await _zippingService.createImageZip(
+        imageFiles: imageFiles.values.toList(),
+        baseFileName: baseFileName,
+        destinationDir: localSubmissionDir, // Save ZIP in the specific log folder
+      );
+      if (imageZip != null) {
+        ftpImageResult = await _submissionFtpService.submit(
+            moduleName: moduleName, // 'river_investigative'
+            fileToUpload: imageZip,
+            remotePath: '/${p.basename(imageZip.path)}' // Standard remote path
+        );
+      }
+    }
+
+
+    // Combine statuses from both uploads
+    return {
+      'statuses': <Map<String, dynamic>>[
+        ...(ftpDataResult['statuses'] as List? ?? []), // Use null-aware spread
+        ...(ftpImageResult['statuses'] as List? ?? []), // Use null-aware spread
+      ],
+    };
+  }
+
+  /// Saves or updates the local log file and saves a record to the central DB log (Investigative).
+  Future<void> _logAndSave({
+    required RiverInvesManualSamplingData data, // Updated model type
+    required String status,
+    required String message,
+    required List<Map<String, dynamic>> apiResults,
+    required List<Map<String, dynamic>> ftpStatuses,
+    required String serverName,
+    String? logDirectory, // Can be null initially, gets populated on first save
+  }) async {
+    data.submissionStatus = status;
+    data.submissionMessage = message;
+    final baseFileName = _generateBaseFileName(data); // Use helper for consistent naming
+
+    // Prepare log data map using toMap()
+    final Map<String, dynamic> logMapData = data.toMap();
+    // Add submission metadata that might not be in toMap() or needs overriding
+    logMapData['submissionStatus'] = status;
+    logMapData['submissionMessage'] = message;
+    logMapData['reportId'] = data.reportId;
+    logMapData['serverConfigName'] = serverName;
+    // Store API/FTP results as JSON strings
+    logMapData['api_status'] = jsonEncode(apiResults); // Ensure apiResults is a list
+    logMapData['ftp_status'] = jsonEncode(ftpStatuses); // Ensure ftpStatuses is a list
+
+    String? savedLogPath = logDirectory;
+
+    // Save or Update local log file (data.json)
+    if (savedLogPath != null && savedLogPath.isNotEmpty) {
+      // Update existing log
+      logMapData['logDirectory'] = savedLogPath; // Ensure logDirectory path is in the map for update method
+      // *** MODIFIED: Use correct update method ***
+      await _localStorageService.updateRiverInvestigativeLog(logMapData); // NEW UPDATE METHOD
+    } else {
+      // Save new log and get the path
+      // *** MODIFIED: Use correct save method ***
+      savedLogPath = await _localStorageService.saveRiverInvestigativeSamplingData(data, serverName: serverName); // NEW SAVE METHOD
+      if (savedLogPath != null) {
+        logMapData['logDirectory'] = savedLogPath; // Add the new path for central log
+      } else {
+        debugPrint("Failed to save River Investigative log locally, central DB log might be incomplete.");
+        // Handle case where local save failed? Maybe skip central log or log with error?
+      }
+    }
+
+
+    // Save record to central DB log (submission_log table)
+    final imagePaths = data.toApiImageFiles().values.whereType<File>().map((f) => f.path).toList();
+    final centralLogData = {
+      'submission_id': data.reportId ?? baseFileName, // Use report ID or generated name as unique ID
+      // *** MODIFIED: Module and Type ***
+      'module': 'river', // Keep main module as 'river'
+      'type': 'Investigative', // Specific type
+      'status': status,
+      'message': message,
+      'report_id': data.reportId,
+      'created_at': DateTime.now().toIso8601String(),
+      'form_data': jsonEncode(logMapData), // Log the comprehensive map including paths and status
+      'image_data': jsonEncode(imagePaths), // Log original image paths used for submission attempt
+      'server_name': serverName,
+      'api_status': jsonEncode(apiResults), // Log API results
+      'ftp_status': jsonEncode(ftpStatuses), // Log FTP results
+    };
+    try {
+      await _dbHelper.saveSubmissionLog(centralLogData);
+    } catch (e) {
+      debugPrint("Error saving River Investigative submission log to DB: $e"); // Log context update
+    }
+  }
+
+
+  /// Handles sending or queuing the Telegram alert for River Investigative submissions.
+  Future<void> _handleSuccessAlert(RiverInvesManualSamplingData data, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly, bool isSessionExpired = false}) async { // Updated model type
+    try {
+      final message = await _generateInvestigativeAlertMessage(data, isDataOnly: isDataOnly); // Call specific helper
+      // *** MODIFIED: Telegram key ***
+      final alertKey = 'river_investigative'; // Specific key for this module
+
+      if (isSessionExpired) {
+        debugPrint("Session is expired; queuing River Investigative Telegram alert directly for $alertKey."); // Log context update
+        await _telegramService.queueMessage(alertKey, message, appSettings);
+      } else {
+        final bool wasSent = await _telegramService.sendAlertImmediately(alertKey, message, appSettings);
+        if (!wasSent) {
+          // Fallback to queueing if immediate send fails
+          await _telegramService.queueMessage(alertKey, message, appSettings);
+        }
+      }
+    } catch (e) {
+      debugPrint("Failed to handle River Investigative Telegram alert: $e"); // Log context update
+    }
+  }
+
+  /// Generates the specific Telegram alert message content for River Investigative.
+  Future<String> _generateInvestigativeAlertMessage(RiverInvesManualSamplingData data, {required bool isDataOnly}) async { // Updated model type
+    final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
+    // Use helpers to get determined names/codes
+    final stationName = data.getDeterminedRiverName() ?? data.getDeterminedStationName() ?? 'N/A'; // Combine river/station name
+    final stationCode = data.getDeterminedStationCode() ?? 'N/A';
+    final submissionDate = data.samplingDate ?? DateFormat('yyyy-MM-dd').format(DateTime.now());
+    final submitter = data.firstSamplerName ?? 'N/A';
+    final sondeID = data.sondeId ?? 'N/A';
+    final distanceKm = data.distanceDifferenceInKm ?? 0;
+    final distanceMeters = (distanceKm * 1000).toStringAsFixed(0);
+    final distanceRemarks = data.distanceDifferenceRemarks ?? ''; // Default to empty string
+
+    final buffer = StringBuffer()
+      ..writeln('✅ *River Investigative Sample ${submissionType} Submitted:*') // Updated title
+      ..writeln();
+
+    // Adapt station info based on type
+    buffer.writeln('*Station Type:* ${data.stationTypeSelection ?? 'N/A'}');
+    if (data.stationTypeSelection == 'New Location') {
+      buffer.writeln('*New Location Name:* ${data.newStationName ?? 'N/A'}');
+      buffer.writeln('*New Location Code:* ${data.newStationCode ?? 'N/A'}');
+      buffer.writeln('*New Location State:* ${data.newStateName ?? 'N/A'}');
+      buffer.writeln('*New Location Basin:* ${data.newBasinName ?? 'N/A'}');
+      buffer.writeln('*New Location River:* ${data.newRiverName ?? 'N/A'}');
+      buffer.writeln('*Coordinates:* ${data.stationLatitude ?? 'N/A'}, ${data.stationLongitude ?? 'N/A'}');
+    } else {
+      buffer.writeln('*Station Name & Code:* $stationName ($stationCode)');
+    }
+
+    buffer
+      ..writeln('*Date of Submitted:* $submissionDate')
+      ..writeln('*Submitted by User:* $submitter')
+      ..writeln('*Sonde ID:* $sondeID')
+      ..writeln('*Status of Submission:* Successful');
+
+    // Include distance warning only if NOT a new location and distance > 50m
+    if (data.stationTypeSelection != 'New Location' && (distanceKm * 1000 > 50 || distanceRemarks.isNotEmpty)) {
+      buffer
+        ..writeln()
+        ..writeln('🔔 *Distance Alert:*')
+        ..writeln('*Distance from station:* $distanceMeters meters');
+      if (distanceRemarks.isNotEmpty) {
+        buffer.writeln('*Remarks for distance:* $distanceRemarks');
+      }
+    }
+
+    // Add parameter limit check section (uses the same river limits)
+    final outOfBoundsAlert = await _getOutOfBoundsAlertSection(data); // Call helper
+    if (outOfBoundsAlert.isNotEmpty) {
+      buffer.write(outOfBoundsAlert);
+    }
+
+    return buffer.toString();
+  }
+
+  /// Helper to generate the parameter limit alert section for Telegram (River Investigative).
+  Future<String> _getOutOfBoundsAlertSection(RiverInvesManualSamplingData data) async { // Updated model type
+    // Define mapping from data model keys to parameter names used in limits table
+    // This mapping should be consistent with River In-Situ
+    const Map<String, String> _parameterKeyToLimitName = {
+      'oxygenConcentration': 'Oxygen Conc', 'oxygenSaturation': 'Oxygen Sat', 'ph': 'pH',
+      'salinity': 'Salinity', 'electricalConductivity': 'Conductivity', 'temperature': 'Temperature',
+      'tds': 'TDS', 'turbidity': 'Turbidity', 'ammonia': 'Ammonia', 'batteryVoltage': 'Battery',
+    };
+
+    // Load the same river parameter limits as In-Situ
+    final allLimits = await _dbHelper.loadRiverParameterLimits() ?? [];
+    if (allLimits.isEmpty) return ""; // No limits defined
+
+    // Get current readings from the investigative data model
+    final readings = {
+      'oxygenConcentration': data.oxygenConcentration, 'oxygenSaturation': data.oxygenSaturation,
+      'ph': data.ph, 'salinity': data.salinity, 'electricalConductivity': data.electricalConductivity,
+      'temperature': data.temperature, 'tds': data.tds, 'turbidity': data.turbidity,
+      'ammonia': data.ammonia, 'batteryVoltage': data.batteryVoltage,
+    };
+
+    final List<String> outOfBoundsMessages = [];
+
+    // Helper to parse limit values (copied from In-Situ)
+    double? parseLimitValue(dynamic value) {
+      if (value == null) return null;
+      if (value is num) return value.toDouble();
+      if (value is String) return double.tryParse(value);
+      return null;
+    }
+
+    // Iterate through readings and check against limits
+    readings.forEach((key, value) {
+      if (value == null || value == -999.0) return; // Skip missing/default values
+
+      final limitName = _parameterKeyToLimitName[key];
+      if (limitName == null) return; // Skip if parameter not in mapping
+
+      // Find the limit data for this parameter
+      final limitData = allLimits.firstWhere(
+            (l) => l['param_parameter_list'] == limitName,
+        orElse: () => <String, dynamic>{}, // Return empty map if not found
+      );
+
+      if (limitData.isNotEmpty) {
+        final lowerLimit = parseLimitValue(limitData['param_lower_limit']);
+        final upperLimit = parseLimitValue(limitData['param_upper_limit']);
+        bool isOutOfBounds = false;
+
+        // Check bounds
+        if (lowerLimit != null && value < lowerLimit) isOutOfBounds = true;
+        if (upperLimit != null && value > upperLimit) isOutOfBounds = true;
+
+        if (isOutOfBounds) {
+          // Format message for Telegram
+          final valueStr = value.toStringAsFixed(5);
+          final lowerStr = lowerLimit?.toStringAsFixed(5) ?? 'N/A';
+          final upperStr = upperLimit?.toStringAsFixed(5) ?? 'N/A';
+          outOfBoundsMessages.add('- *$limitName*: `$valueStr` (Limit: `$lowerStr` - `$upperStr`)');
+        }
+      }
+    });
+
+    // If no parameters were out of bounds, return empty string
+    if (outOfBoundsMessages.isEmpty) {
+      return "";
+    }
+
+    // Construct the alert section header and messages
+    final buffer = StringBuffer()
+      ..writeln() // Add spacing
+      ..writeln('⚠️ *Parameter Limit Alert:*')
+      ..writeln('The following parameters were outside their defined limits:');
+    buffer.writeAll(outOfBoundsMessages, '\n'); // Add each message on a new line
+
+    return buffer.toString();
+  }
+
+} // End of RiverInvestigativeSamplingService class

lib/services/river_manual_triennial_sampling_service.dart

@@ -2,7 +2,7 @@
 
 import 'dart:async';
 import 'dart:io';
-import 'package:flutter/material.dart';
+import 'package:flutter/material.dart'; // Keep material import
 import 'package:flutter/services.dart';
 import 'package:image_picker/image_picker.dart';
 import 'package:path_provider/path_provider.dart';
@@ -15,14 +15,14 @@ import 'package:usb_serial/usb_serial.dart';
 import 'dart:convert';
 import 'package:intl/intl.dart';
 import 'package:connectivity_plus/connectivity_plus.dart';
-import 'package:provider/provider.dart';
+import 'package:provider/provider.dart'; // Keep provider import
 
 import '../auth_provider.dart';
 import 'location_service.dart';
 import '../models/river_manual_triennial_sampling_data.dart';
 import '../bluetooth/bluetooth_manager.dart';
 import '../serial/serial_manager.dart';
-import 'api_service.dart';
+import 'api_service.dart'; // Keep DatabaseHelper import
 import 'local_storage_service.dart';
 import 'server_config_service.dart';
 import 'zipping_service.dart';
@@ -166,18 +166,23 @@ class RiverManualTriennialSamplingService {
     required AuthProvider authProvider,
     String? logDirectory,
   }) async {
-    const String moduleName = 'river_triennial';
+    const String moduleName = 'river_triennial'; // Correct module name
 
     final connectivityResult = await Connectivity().checkConnectivity();
-    bool isOnline = connectivityResult != ConnectivityResult.none;
+    bool isOnline = !connectivityResult.contains(ConnectivityResult.none);
     bool isOfflineSession = authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
 
     if (isOnline && isOfflineSession) {
       debugPrint("River Triennial submission online during offline session. Attempting auto-relogin...");
+      try {
         final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
         if (transitionSuccess) {
           isOfflineSession = false;
         } else {
+          isOnline = false; // Auto-relogin failed, treat as offline
+        }
+      } on SessionExpiredException catch (_) {
+        debugPrint("Session expired during auto-relogin check. Treating as offline.");
         isOnline = false;
       }
     }
@@ -196,6 +201,7 @@ class RiverManualTriennialSamplingService {
       return await _performOfflineQueuing(
         data: data,
         moduleName: moduleName,
+        logDirectory: logDirectory, // Pass for potential update
       );
     }
   }
@@ -215,25 +221,29 @@ class RiverManualTriennialSamplingService {
     bool anyApiSuccess = false;
     Map<String, dynamic> apiDataResult = {};
     Map<String, dynamic> apiImageResult = {};
+    String finalMessage = '';
+    String finalStatus = '';
     bool isSessionKnownToBeExpired = false;
 
     try {
+      // 1. Submit Form Data
       apiDataResult = await _submissionApiService.submitPost(
         moduleName: moduleName,
-        endpoint: 'river/triennial/sample',
+        endpoint: 'river/triennial/sample', // Correct endpoint
         body: data.toApiFormData(),
       );
 
       if (apiDataResult['success'] == true) {
         anyApiSuccess = true;
-        data.reportId = apiDataResult['data']?['r_tri_id']?.toString();
+        data.reportId = apiDataResult['data']?['r_tri_id']?.toString(); // Correct ID key
 
         if (data.reportId != null) {
           if (finalImageFiles.isNotEmpty) {
+            // 2. Submit Images
             apiImageResult = await _submissionApiService.submitMultipart(
               moduleName: moduleName,
-              endpoint: 'river/triennial/images',
-              fields: {'r_tri_id': data.reportId!},
+              endpoint: 'river/triennial/images', // Correct endpoint
+              fields: {'r_tri_id': data.reportId!}, // Correct field key
               files: finalImageFiles,
             );
             if (apiImageResult['success'] != true) {
@@ -245,65 +255,96 @@ class RiverManualTriennialSamplingService {
           apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
         }
       }
-    } on SessionExpiredException catch (_) {
-      debugPrint("API submission failed with SessionExpiredException. Attempting silent relogin...");
-      final bool reloginSuccess = await authProvider.attemptSilentRelogin();
+      // If apiDataResult['success'] is false, SubmissionApiService queued it.
 
-      if (reloginSuccess) {
-        debugPrint("Silent relogin successful. Retrying entire online submission process...");
-        return await _performOnlineSubmission(
-          data: data,
-          appSettings: appSettings,
-          moduleName: moduleName,
-          authProvider: authProvider,
-          logDirectory: logDirectory,
-        );
-      } else {
-        debugPrint("Silent relogin failed. API part will be queued, proceeding with FTP.");
+    } on SessionExpiredException catch (_) {
+      debugPrint("Online submission failed due to session expiry that could not be refreshed.");
       isSessionKnownToBeExpired = true;
       anyApiSuccess = false;
       apiDataResult = {'success': false, 'message': 'Session expired and re-login failed. API submission queued.'};
-        await _retryService.addApiToQueue(endpoint: 'river/triennial/sample', method: 'POST', body: data.toApiFormData());
-      }
-    } on SocketException catch (e) {
-      final errorMessage = "API submission failed with network error: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
+      // Manually queue API calls
       await _retryService.addApiToQueue(endpoint: 'river/triennial/sample', method: 'POST', body: data.toApiFormData());
       if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        // Also queue images if data call might have partially succeeded before expiry
         await _retryService.addApiToQueue(endpoint: 'river/triennial/images', method: 'POST_MULTIPART', fields: {'r_tri_id': data.reportId!}, files: finalImageFiles);
       }
-    } on TimeoutException catch (e) {
-      final errorMessage = "API submission timed out: $e";
-      debugPrint(errorMessage);
-      anyApiSuccess = false;
-      apiDataResult = {'success': false, 'message': errorMessage};
-      await _retryService.addApiToQueue(endpoint: 'river/triennial/sample', method: 'POST', body: data.toApiFormData());
     }
 
+    // 3. Submit FTP Files
     Map<String, dynamic> ftpResults = {'statuses': []};
     bool anyFtpSuccess = false;
+
+    if (isSessionKnownToBeExpired) {
+      debugPrint("Skipping FTP attempt due to known expired session. Manually queuing FTP tasks.");
+      final baseFileNameForQueue = _generateBaseFileName(data); // Use helper
+
+      // --- START FIX: Add ftpConfigId when queuing ---
+      // Get all potential FTP configs
+      final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
+
+      final dataZip = await _zippingService.createDataZip(
+        jsonDataMap: { // Use specific JSON structures for River Triennial FTP
+          'db.json': data.toDbJson(), // Assuming similar structure is needed, adjust if different
+          // Add other JSON files if required for Triennial FTP
+        },
+        baseFileName: baseFileNameForQueue,
+        destinationDir: null,
+      );
+      if (dataZip != null) {
+        // Queue for each config separately
+        for (final config in ftpConfigs) {
+          final configId = config['ftp_config_id'];
+          if (configId != null) {
+            await _retryService.addFtpToQueue(
+                localFilePath: dataZip.path,
+                remotePath: '/${p.basename(dataZip.path)}',
+                ftpConfigId: configId // Provide the specific config ID
+            );
+          }
+        }
+      }
+
+      if (finalImageFiles.isNotEmpty) {
+        final imageZip = await _zippingService.createImageZip(
+          imageFiles: finalImageFiles.values.toList(),
+          baseFileName: baseFileNameForQueue,
+          destinationDir: null,
+        );
+        if (imageZip != null) {
+          // Queue for each config separately
+          for (final config in ftpConfigs) {
+            final configId = config['ftp_config_id'];
+            if (configId != null) {
+              await _retryService.addFtpToQueue(
+                  localFilePath: imageZip.path,
+                  remotePath: '/${p.basename(imageZip.path)}',
+                  ftpConfigId: configId // Provide the specific config ID
+              );
+            }
+          }
+        }
+      }
+      // --- END FIX ---
+      ftpResults = {'statuses': [{'status': 'Queued', 'message': 'FTP upload queued due to API session issue.', 'success': false}]};
+      anyFtpSuccess = false;
+    } else {
       try {
         ftpResults = await _generateAndUploadFtpFiles(data, finalImageFiles, serverName, moduleName);
         anyFtpSuccess = !(ftpResults['statuses'] as List).any((status) => status['success'] == false && status['status'] != 'Not Configured');
-    } on SocketException catch (e) {
-      debugPrint("FTP submission failed with network error: $e");
-      anyFtpSuccess = false;
-    } on TimeoutException catch (e) {
-      debugPrint("FTP submission timed out: $e");
+      } catch (e) {
+        debugPrint("Unexpected FTP submission error: $e");
         anyFtpSuccess = false;
       }
+    }
 
+    // 4. Determine Final Status
     final bool overallSuccess = anyApiSuccess || anyFtpSuccess;
-    String finalMessage;
-    String finalStatus;
 
     if (anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'Data submitted successfully to all destinations.';
       finalStatus = 'S4';
     } else if (anyApiSuccess && !anyFtpSuccess) {
-      finalMessage = 'Data sent to API, but some FTP uploads failed and were queued.';
+      finalMessage = 'Data sent to API, but some FTP uploads failed or were queued.';
       finalStatus = 'S3';
     } else if (!anyApiSuccess && anyFtpSuccess) {
       finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
@@ -313,6 +354,7 @@ class RiverManualTriennialSamplingService {
       finalStatus = 'L1';
     }
 
+    // 5. Log Locally
     await _logAndSave(
       data: data,
       status: finalStatus,
@@ -323,10 +365,12 @@ class RiverManualTriennialSamplingService {
       logDirectory: logDirectory,
     );
 
+    // 6. Send Alert
     if (overallSuccess) {
       _handleSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty, isSessionExpired: isSessionKnownToBeExpired);
     }
 
+    // Return consistent format
     return {
       'status': finalStatus,
       'success': overallSuccess,
@@ -335,9 +379,11 @@ class RiverManualTriennialSamplingService {
     };
   }
 
+  /// Handles queuing the submission data when the device is offline.
   Future<Map<String, dynamic>> _performOfflineQueuing({
     required RiverManualTriennialSamplingData data,
     required String moduleName,
+    String? logDirectory, // Added for potential update
   }) async {
     final serverConfig = await _serverConfigService.getActiveApiConfig();
     final serverName = serverConfig?['config_name'] as String? ?? 'Default';
@@ -345,45 +391,67 @@ class RiverManualTriennialSamplingService {
     data.submissionStatus = 'L1';
     data.submissionMessage = 'Submission queued for later retry.';
 
-    final String? localLogPath = await _localStorageService.saveRiverManualTriennialSamplingData(data, serverName: serverName);
+    String? savedLogPath = logDirectory; // Use existing path if provided
 
-    if (localLogPath == null) {
+    // Save/Update local log first
+    if (savedLogPath != null && savedLogPath.isNotEmpty) {
+      await _localStorageService.updateRiverManualTriennialLog(data.toMap()..['logDirectory'] = savedLogPath);
+      debugPrint("Updated existing River Triennial log for queuing: $savedLogPath");
+    } else {
+      savedLogPath = await _localStorageService.saveRiverManualTriennialSamplingData(data, serverName: serverName);
+      debugPrint("Saved new River Triennial log for queuing: $savedLogPath");
+    }
+
+
+    if (savedLogPath == null) {
       const message = "Failed to save submission to local device storage.";
-      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName);
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, logDirectory: logDirectory);
       return {'status': 'Error', 'success': false, 'message': message};
     }
 
     await _retryService.queueTask(
-      type: 'river_triennial_submission',
+      type: 'river_triennial_submission', // Correct type
       payload: {
         'module': moduleName,
-        'localLogPath': p.join(localLogPath, 'data.json'),
+        'localLogPath': p.join(savedLogPath, 'data.json'), // Point to the json file
         'serverConfig': serverConfig,
       },
     );
 
-    const successMessage = "Submission failed to send and has been queued for later retry.";
-    return {'status': 'Queued', 'success': true, 'message': successMessage};
+    const successMessage = "Device offline. Submission has been saved locally and queued for automatic retry when connection is restored.";
+    // Log final queued state to central DB
+    // await _logAndSave(data: data, status: 'Queued', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, logDirectory: savedLogPath);
+
+    return {'status': 'Queued', 'success': true, 'message': successMessage, 'reportId': null};
   }
 
-  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(RiverManualTriennialSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+  /// Helper to generate the base filename for ZIP files.
+  String _generateBaseFileName(RiverManualTriennialSamplingData data) {
     final stationCode = data.selectedStation?['sampling_station_code'] ?? 'UNKNOWN';
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
-    final baseFileName = "${stationCode}_$fileTimestamp";
+    return "${stationCode}_$fileTimestamp";
+  }
 
-    final Directory? logDirectory = await _localStorageService.getLogDirectory(
+
+  /// Generates data and image ZIP files and uploads them using SubmissionFtpService.
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(RiverManualTriennialSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
+    final baseFileName = _generateBaseFileName(data);
+
+    final Directory? logDirectory = await _localStorageService.getLogDirectory( // Use generic getter
       serverName: serverName,
       module: 'river',
-      subModule: 'river_triennial_sampling',
+      subModule: 'river_triennial_sampling', // Correct sub-module path
     );
 
-    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
+    final folderName = data.reportId ?? baseFileName;
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, folderName)) : null;
     if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
       await localSubmissionDir.create(recursive: true);
     }
 
+    // Create and upload data ZIP
     final dataZip = await _zippingService.createDataZip(
-      jsonDataMap: {'db.json': jsonEncode(data.toApiFormData())}, // Assuming similar structure is needed
+      jsonDataMap: {'db.json': data.toDbJson()}, // Assuming similar structure, adjust if needed
       baseFileName: baseFileName,
       destinationDir: localSubmissionDir,
     );
@@ -393,6 +461,7 @@ class RiverManualTriennialSamplingService {
           moduleName: moduleName, fileToUpload: dataZip, remotePath: '/${p.basename(dataZip.path)}');
     }
 
+    // Create and upload image ZIP
     final imageZip = await _zippingService.createImageZip(
       imageFiles: imageFiles.values.toList(),
       baseFileName: baseFileName,
@@ -406,12 +475,13 @@ class RiverManualTriennialSamplingService {
 
     return {
       'statuses': <Map<String, dynamic>>[
-        ...(ftpDataResult['statuses'] as List),
-        ...(ftpImageResult['statuses'] as List),
+        ...(ftpDataResult['statuses'] as List? ?? []), // Use null-aware spread
+        ...(ftpImageResult['statuses'] as List? ?? []), // Use null-aware spread
       ],
     };
   }
 
+  /// Saves or updates the local log file and saves a record to the central DB log.
   Future<void> _logAndSave({
     required RiverManualTriennialSamplingData data,
     required String status,
@@ -423,47 +493,65 @@ class RiverManualTriennialSamplingService {
   }) async {
     data.submissionStatus = status;
     data.submissionMessage = message;
+    final baseFileName = _generateBaseFileName(data); // Use helper
 
-    if (logDirectory != null) {
-      final Map<String, dynamic> updatedLogData = data.toMap();
-      updatedLogData['logDirectory'] = logDirectory;
-      updatedLogData['serverConfigName'] = serverName;
-      updatedLogData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
-      updatedLogData['ftp_status'] = jsonEncode(ftpStatuses);
+    // Prepare log data map using toMap()
+    final Map<String, dynamic> logMapData = data.toMap();
+    // Add submission metadata
+    logMapData['submissionStatus'] = status;
+    logMapData['submissionMessage'] = message;
+    logMapData['reportId'] = data.reportId;
+    logMapData['serverConfigName'] = serverName;
+    logMapData['api_status'] = jsonEncode(apiResults.where((r) => r.isNotEmpty).toList());
+    logMapData['ftp_status'] = jsonEncode(ftpStatuses);
 
-      final imageFilePaths = data.toApiImageFiles();
-      imageFilePaths.forEach((key, file) {
-        if (file != null) {
-          updatedLogData[key] = file.path;
-        }
-      });
 
-      await _localStorageService.updateRiverManualTriennialLog(updatedLogData);
+    if (logDirectory != null && logDirectory.isNotEmpty) {
+      // Update existing log
+      logMapData['logDirectory'] = logDirectory; // Ensure logDirectory path is in the map
+      await _localStorageService.updateRiverManualTriennialLog(logMapData); // Use specific update method
     } else {
-      await _localStorageService.saveRiverManualTriennialSamplingData(data, serverName: serverName);
+      // Save new log
+      await _localStorageService.saveRiverManualTriennialSamplingData(data, serverName: serverName); // Use specific save method
     }
 
+    // Save to central DB log
     final imagePaths = data.toApiImageFiles().values.whereType<File>().map((f) => f.path).toList();
-    final logData = {
-      'submission_id': data.reportId ?? DateTime.now().millisecondsSinceEpoch.toString(),
-      'module': 'river', 'type': data.samplingType ?? 'Triennial', 'status': status,
-      'message': message, 'report_id': data.reportId, 'created_at': DateTime.now().toIso8601String(),
-      'form_data': jsonEncode(data.toMap()), 'image_data': jsonEncode(imagePaths),
-      'server_name': serverName, 'api_status': jsonEncode(apiResults), 'ftp_status': jsonEncode(ftpStatuses),
+    final centralLogData = {
+      'submission_id': data.reportId ?? baseFileName, // Use helper result
+      'module': 'river',
+      'type': data.samplingType ?? 'Triennial', // Correct type
+      'status': status,
+      'message': message,
+      'report_id': data.reportId,
+      'created_at': DateTime.now().toIso8601String(),
+      'form_data': jsonEncode(logMapData), // Log the comprehensive map
+      'image_data': jsonEncode(imagePaths),
+      'server_name': serverName,
+      'api_status': jsonEncode(apiResults),
+      'ftp_status': jsonEncode(ftpStatuses),
     };
-    await _dbHelper.saveSubmissionLog(logData);
+    try {
+      await _dbHelper.saveSubmissionLog(centralLogData);
+    } catch (e) {
+      debugPrint("Error saving River Triennial submission log to DB: $e");
+    }
   }
 
+
+  /// Handles sending or queuing the Telegram alert for River Triennial submissions.
   Future<void> _handleSuccessAlert(RiverManualTriennialSamplingData data, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly, bool isSessionExpired = false}) async {
     try {
-      final message = await _generateSuccessAlertMessage(data, isDataOnly: isDataOnly);
+      final message = await _generateSuccessAlertMessage(data, isDataOnly: isDataOnly); // Call local helper
+      final alertKey = 'river_triennial'; // Correct key
+
       if (isSessionExpired) {
-        debugPrint("Session is expired; queuing Telegram alert directly.");
-        await _telegramService.queueMessage('river_triennial', message, appSettings);
+        debugPrint("Session is expired; queuing Telegram alert directly for $alertKey.");
+        await _telegramService.queueMessage(alertKey, message, appSettings);
       } else {
-        final bool wasSent = await _telegramService.sendAlertImmediately('river_triennial', message, appSettings);
+        final bool wasSent = await _telegramService.sendAlertImmediately(alertKey, message, appSettings);
         if (!wasSent) {
-          await _telegramService.queueMessage('river_triennial', message, appSettings);
+          await _telegramService.queueMessage(alertKey, message, appSettings);
         }
       }
     } catch (e) {
@@ -471,6 +559,7 @@ class RiverManualTriennialSamplingService {
     }
   }
 
+  /// Generates the specific Telegram alert message content for River Triennial.
   Future<String> _generateSuccessAlertMessage(RiverManualTriennialSamplingData data, {required bool isDataOnly}) async {
     final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
     final stationName = data.selectedStation?['sampling_river'] ?? 'N/A';
@@ -491,15 +580,20 @@ class RiverManualTriennialSamplingService {
       ..writeln('*Sonde ID:* $sondeID')
       ..writeln('*Status of Submission:* Successful');
 
-    if (distanceKm > 0 || (distanceRemarks.isNotEmpty && distanceRemarks != 'N/A')) {
+    if (distanceKm * 1000 > 50 || (distanceRemarks.isNotEmpty && distanceRemarks != 'N/A')) { // Check if distance > 50m
       buffer
         ..writeln()
-        ..writeln('🔔 *Alert:*')
+        ..writeln('🔔 *Distance Alert:*')
         ..writeln('*Distance from station:* $distanceMeters meters');
       if (distanceRemarks.isNotEmpty && distanceRemarks != 'N/A') {
         buffer.writeln('*Remarks for distance:* $distanceRemarks');
       }
     }
+
+    // Note: Parameter limit checks are not typically done for Triennial in the same way as In-Situ.
+    // If needed, similar logic to _getOutOfBoundsAlertSection in RiverInSituSamplingService
+    // would need to be adapted here, potentially using riverParameterLimits from the DB.
+
     return buffer.toString();
   }
 }

lib/services/submission_ftp_service.dart

@@ -2,10 +2,15 @@
 
 import 'dart:io';
 import 'package:flutter/foundation.dart';
+import 'dart:convert'; // Added for jsonEncode
+import 'package:path/path.dart' as p; // Added for basename
 
 import 'package:environment_monitoring_app/services/user_preferences_service.dart';
 import 'package:environment_monitoring_app/services/ftp_service.dart';
 import 'package:environment_monitoring_app/services/retry_service.dart';
+// Import necessary services and models if needed for queueFtpTasksForSkippedAttempt
+import 'package:environment_monitoring_app/services/zipping_service.dart';
+import 'package:environment_monitoring_app/services/api_service.dart'; // For DatabaseHelper
 
 /// A generic, reusable service for handling the FTP submission process.
 /// It respects user preferences for enabled destinations for any given module.
@@ -13,6 +18,10 @@ class SubmissionFtpService {
   final UserPreferencesService _userPreferencesService = UserPreferencesService();
   final FtpService _ftpService = FtpService();
   final RetryService _retryService = RetryService();
+  // Add ZippingService and DatabaseHelper if queueFtpTasksForSkippedAttempt needs them
+  final ZippingService _zippingService = ZippingService();
+  final DatabaseHelper _dbHelper = DatabaseHelper();
+
 
   /// Submits a file to all enabled FTP destinations for a given module.
   ///
@@ -30,15 +39,35 @@ class SubmissionFtpService {
 
     if (destinations.isEmpty) {
       debugPrint("SubmissionFtpService: No enabled FTP destinations for module '$moduleName'. Skipping.");
-      return {'success': true, 'message': 'No FTP destinations enabled for this module.'};
+      // Return success with a specific status indicating no config
+      return {
+        'success': true, // Process succeeded because there was nothing to do
+        'message': 'No FTP destinations enabled for this module.',
+        'statuses': [{'status': 'Not Configured', 'message': 'No destinations enabled.', 'success': true}]
+      };
     }
 
     final List<Map<String, dynamic>> statuses = [];
-    bool allSucceeded = true;
+    bool allSucceededOrNotConfigured = true; // Track if all attempts either succeeded or weren't configured
 
     for (final dest in destinations) {
       final configName = dest['config_name'] as String? ?? 'Unknown FTP';
-      debugPrint("SubmissionFtpService: Attempting to upload to '$configName'");
+      final int? configId = dest['ftp_config_id'] as int?; // Get the config ID
+
+      // Skip if config ID is missing (should not happen with DB data)
+      if (configId == null) {
+        debugPrint("SubmissionFtpService: Skipping destination '$configName' due to missing config ID.");
+        statuses.add({
+          'config_name': configName,
+          'status': 'Error',
+          'success': false,
+          'message': 'Configuration ID missing.',
+        });
+        allSucceededOrNotConfigured = false;
+        continue;
+      }
+
+      debugPrint("SubmissionFtpService: Attempting to upload to '$configName' (ID: $configId)");
 
       final result = await _ftpService.uploadFile(
         config: dest,
@@ -48,22 +77,27 @@ class SubmissionFtpService {
 
       statuses.add({
         'config_name': configName,
+        'ftp_config_id': configId, // Include ID in status
         'success': result['success'],
         'message': result['message'],
+        'status': result['success'] ? 'Success' : 'Failed', // Add status text
       });
 
       if (result['success'] != true) {
-        allSucceeded = false;
+        allSucceededOrNotConfigured = false;
         // If an individual upload fails, queue it for manual retry.
-        debugPrint("SubmissionFtpService: Upload to '$configName' failed. Queuing for retry.");
+        debugPrint("SubmissionFtpService: Upload to '$configName' (ID: $configId) failed. Queuing for retry.");
+        // --- START FIX: Add ftpConfigId ---
         await _retryService.addFtpToQueue(
           localFilePath: fileToUpload.path,
           remotePath: remotePath,
+          ftpConfigId: configId, // Pass the specific config ID
         );
+        // --- END FIX ---
       }
     }
 
-    if (allSucceeded) {
+    if (allSucceededOrNotConfigured) {
       return {
         'success': true,
         'message': 'File successfully uploaded to all enabled FTP destinations.',
@@ -71,10 +105,70 @@ class SubmissionFtpService {
       };
     } else {
       return {
-        'success': true, // The process itself succeeded, even if some uploads were queued.
+        'success': true, // The process itself succeeded (attempted all), even if some uploads were queued.
         'message': 'One or more FTP uploads failed and have been queued for retry.',
         'statuses': statuses,
       };
     }
   }
+
+  /// Manually queues FTP tasks when the initial FTP attempt is skipped (e.g., due to session expiry).
+  Future<void> queueFtpTasksForSkippedAttempt({
+    required String moduleName,
+    required Map<String, dynamic> dataJson, // The data model converted to JSON (toDbJson)
+    required Map<String, File> imageFiles,
+    required String baseFileName, // Base name for zip files
+  }) async {
+    debugPrint("Manually queuing FTP tasks for skipped attempt (Module: $moduleName).");
+    final ftpConfigs = await _dbHelper.loadFtpConfigs() ?? [];
+    if (ftpConfigs.isEmpty) {
+      debugPrint("Cannot queue skipped FTP tasks: No FTP configurations found.");
+      return;
+    }
+
+    // 1. Create Data ZIP (in temp directory)
+    final dataZip = await _zippingService.createDataZip(
+      // Adapt jsonDataMap based on module if needed, using dataJson
+      jsonDataMap: {'db.json': jsonEncode(dataJson)}, // Default, adjust per module if needed
+      baseFileName: baseFileName,
+      destinationDir: null, // Save to temp dir
+    );
+
+    // 2. Create Image ZIP (in temp directory)
+    File? imageZip;
+    if (imageFiles.isNotEmpty) {
+      imageZip = await _zippingService.createImageZip(
+        imageFiles: imageFiles.values.toList(),
+        baseFileName: baseFileName,
+        destinationDir: null, // Save to temp dir
+      );
+    }
+
+    // 3. Queue uploads for each config
+    for (final config in ftpConfigs) {
+      final configId = config['ftp_config_id'];
+      if (configId != null) {
+        // Queue data zip upload
+        if (dataZip != null) {
+          await _retryService.addFtpToQueue(
+              localFilePath: dataZip.path,
+              remotePath: '/${p.basename(dataZip.path)}',
+              ftpConfigId: configId
+          );
+          debugPrint("Queued skipped data ZIP upload for FTP config ID $configId");
+        }
+        // Queue image zip upload
+        if (imageZip != null) {
+          await _retryService.addFtpToQueue(
+              localFilePath: imageZip.path,
+              remotePath: '/${p.basename(imageZip.path)}',
+              ftpConfigId: configId
+          );
+          debugPrint("Queued skipped image ZIP upload for FTP config ID $configId");
+        }
+      }
+    }
+    // Temporary ZIP files will be cleaned up by OS eventually, or handled by retry logic upon success/failure.
+  }
+
 }

pubspec.lock

@@ -854,6 +854,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.5.5"
+  sqflite_common_ffi:
+    dependency: "direct main"
+    description:
+      name: sqflite_common_ffi
+      sha256: "9faa2fedc5385ef238ce772589f7718c24cdddd27419b609bb9c6f703ea27988"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.6"
   sqflite_darwin:
     dependency: transitive
     description:
@@ -870,6 +878,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.4.0"
+  sqlite3:
+    dependency: transitive
+    description:
+      name: sqlite3
+      sha256: f18fd9a72d7a1ad2920db61368f2a69368f1cc9b56b8233e9d83b47b0a8435aa
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.9.3"
   stack_trace:
     dependency: transitive
     description:

pubspec.yaml

@@ -23,6 +23,7 @@ dependencies:
   # --- Local Storage & Offline Capabilities ---
   shared_preferences: ^2.2.3
   sqflite: ^2.3.3
+  sqflite_common_ffi: ^2.3.3
   path_provider: ^2.1.3
   path: ^1.8.3 # Explicitly added for path manipulation
   connectivity_plus: ^6.0.1
@@ -73,4 +74,4 @@ flutter:
 flutter_launcher_icons:
   android: true
   ios: true
-  image_path: "assets/icon_2_512x512.png"
+  image_path: "assets/icon_3_512x512.png"