diff --git a/lib/auth_provider.dart b/lib/auth_provider.dart
index 73575ba..1c0247b 100644
--- a/lib/auth_provider.dart
+++ b/lib/auth_provider.dart
@@ -1,27 +1,22 @@
+// lib/auth_provider.dart
+
+import 'package:flutter/foundation.dart'; // Import for compute function
 import 'package:flutter/material.dart';
 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:environment_monitoring_app/services/api_service.dart';
-// --- ADDED: Import for the service that manages active server configurations ---
 import 'package:environment_monitoring_app/services/server_config_service.dart';
-// --- ADDED: Import for the new service that manages the retry queue ---
 import 'package:environment_monitoring_app/services/retry_service.dart';
 
-
-/// A comprehensive provider to manage user authentication, session state,
-/// and cached master data for offline use.
 class AuthProvider with ChangeNotifier {
-  // FIX: Change to late final and remove direct instantiation.
   late final ApiService _apiService;
   late final DatabaseHelper _dbHelper;
-  // --- ADDED: Instance of the ServerConfigService to set the initial URL ---
   late final ServerConfigService _serverConfigService;
-  // --- ADDED: Instance of the RetryService to manage pending tasks ---
   late final RetryService _retryService;
 
-
   // --- Session & Profile State ---
   String? _jwtToken;
   String? _userEmail;
@@ -30,6 +25,9 @@ class AuthProvider with ChangeNotifier {
   String? get userEmail => _userEmail;
   Map<String, dynamic>? get profileData => _profileData;
 
+  // --- ADDED: Temporary password cache for auto-relogin ---
+  String? _tempOfflinePassword;
+
   // --- App State ---
   bool _isLoading = true;
   bool _isFirstLogin = true;
@@ -55,12 +53,9 @@ class AuthProvider with ChangeNotifier {
   List<Map<String, dynamic>>? _parameterLimits;
   List<Map<String, dynamic>>? _apiConfigs;
   List<Map<String, dynamic>>? _ftpConfigs;
-  // --- ADDED: State variable for the list of documents ---
   List<Map<String, dynamic>>? _documents;
-  // --- ADDED: State variable for the list of tasks pending manual retry ---
   List<Map<String, dynamic>>? _pendingRetries;
 
-
   // --- Getters for UI access ---
   List<Map<String, dynamic>>? get allUsers => _allUsers;
   List<Map<String, dynamic>>? get tarballStations => _tarballStations;
@@ -78,12 +73,9 @@ class AuthProvider with ChangeNotifier {
   List<Map<String, dynamic>>? get parameterLimits => _parameterLimits;
   List<Map<String, dynamic>>? get apiConfigs => _apiConfigs;
   List<Map<String, dynamic>>? get ftpConfigs => _ftpConfigs;
-  // --- ADDED: Getter for the list of documents ---
   List<Map<String, dynamic>>? get documents => _documents;
-  // --- ADDED: Getter for the list of tasks pending manual retry ---
   List<Map<String, dynamic>>? get pendingRetries => _pendingRetries;
 
-
   // --- SharedPreferences Keys ---
   static const String tokenKey = 'jwt_token';
   static const String userEmailKey = 'user_email';
@@ -91,7 +83,6 @@ class AuthProvider with ChangeNotifier {
   static const String lastSyncTimestampKey = 'last_sync_timestamp';
   static const String isFirstLoginKey = 'is_first_login';
 
-  // FIX: Constructor now accepts dependencies.
   AuthProvider({
     required ApiService apiService,
     required DatabaseHelper dbHelper,
@@ -105,7 +96,6 @@ class AuthProvider with ChangeNotifier {
     _loadSessionAndSyncData();
   }
 
-  /// Loads the user session from storage and then triggers a data sync.
   Future<void> _loadSessionAndSyncData() async {
     _isLoading = true;
     notifyListeners();
@@ -115,36 +105,32 @@ class AuthProvider with ChangeNotifier {
     _userEmail = prefs.getString(userEmailKey);
     _isFirstLogin = prefs.getBool(isFirstLoginKey) ?? true;
 
-    // --- MODIFIED: Logic to insert a default URL on the first ever run ---
-    // Check if there is an active API configuration.
     final activeApiConfig = await _serverConfigService.getActiveApiConfig();
     if (activeApiConfig == null) {
-      // If no config is set (which will be true on the very first launch),
-      // we programmatically create and set a default one.
       debugPrint("AuthProvider: No active API config found. Setting default bootstrap URL.");
       final initialConfig = {
         'api_config_id': 0,
         'config_name': 'Default Server',
-        'api_url': 'https://dev14.pstw.com.my/v1',
+        'api_url': 'https://mms-apiv4.pstw.com.my/v1',
       };
-      // Save this default config as the active one.
       await _serverConfigService.setActiveApiConfig(initialConfig);
     }
-    // --- END OF MODIFICATION ---
 
-    // MODIFIED: Switched to getting a string for the ISO8601 timestamp
     final lastSyncString = prefs.getString(lastSyncTimestampKey);
     if (lastSyncString != null) {
-      _lastSyncTimestamp = DateTime.parse(lastSyncString);
+      try {
+        _lastSyncTimestamp = DateTime.parse(lastSyncString);
+      } catch (e) {
+        debugPrint("Error parsing last sync timestamp: $e");
+        prefs.remove(lastSyncTimestampKey);
+      }
     }
 
-    // Always load from local DB first for instant startup
     await _loadDataFromCache();
 
     if (_jwtToken != null) {
-      debugPrint('AuthProvider: Session loaded. Triggering online sync.');
-      // Don't await here to allow the UI to build instantly with cached data
-      syncAllData();
+      debugPrint('AuthProvider: Session loaded.');
+      // Sync logic moved to checkAndTransitionToOnlineSession to handle transitions correctly
     } else {
       debugPrint('AuthProvider: No active session. App is in offline mode.');
     }
@@ -153,40 +139,127 @@ class AuthProvider with ChangeNotifier {
     notifyListeners();
   }
 
-  /// The main function to sync all app data using the delta-sync strategy.
+  /// Checks if the session is offline and attempts to transition to an online session by performing a silent re-login.
+  /// Returns true if a successful transition occurred.
+  Future<bool> checkAndTransitionToOnlineSession() async {
+    // Condition 1: Check connectivity
+    final connectivityResult = await Connectivity().checkConnectivity();
+    if (connectivityResult.contains(ConnectivityResult.none)) {
+      debugPrint("AuthProvider: No internet connection. Skipping transition check.");
+      return false;
+    }
+
+    // Condition 2: Check if currently in an offline session state
+    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.
+      if(_jwtToken != null) {
+        debugPrint("AuthProvider: Session is already online. Triggering standard sync.");
+        syncAllData();
+      }
+      return false;
+    }
+
+    // Condition 3: Check if we have the temporary password to attempt re-login.
+    if (_tempOfflinePassword == null || _userEmail == null) {
+      debugPrint("AuthProvider: In offline session, but no temporary password available for auto-relogin. Manual login required.");
+      return false;
+    }
+
+    debugPrint("AuthProvider: Internet detected in offline session. Attempting silent re-login for $_userEmail...");
+
+    try {
+      final result = await _apiService.login(_userEmail!, _tempOfflinePassword!);
+
+      if (result['success'] == true) {
+        debugPrint("AuthProvider: Silent re-login successful. Transitioning to online session.");
+        final String token = result['data']['token'];
+        final Map<String, dynamic> profile = result['data']['profile'];
+
+        // Use existing login method to set up session and trigger sync.
+        // Re-pass the password to ensure credentials are fully cached after transition.
+        await login(token, profile, _tempOfflinePassword!);
+
+        // Clear temporary password after successful transition
+        _tempOfflinePassword = null;
+        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.
+        debugPrint("AuthProvider: Silent re-login failed: ${result['message']}");
+        return false;
+      }
+    } catch (e) {
+      debugPrint("AuthProvider: Silent re-login exception: $e");
+      return false;
+    }
+  }
+
+  /// 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 {
+    final connectivityResult = await Connectivity().checkConnectivity();
+    if (connectivityResult.contains(ConnectivityResult.none)) {
+      debugPrint("AuthProvider: No internet for silent relogin.");
+      return false;
+    }
+
+    if (_tempOfflinePassword == null || _userEmail == null) {
+      debugPrint("AuthProvider: No cached credentials for silent relogin.");
+      return false;
+    }
+
+    debugPrint("AuthProvider: Session may be expired. Attempting silent re-login for $_userEmail...");
+    try {
+      final result = await _apiService.login(_userEmail!, _tempOfflinePassword!);
+      if (result['success'] == true) {
+        debugPrint("AuthProvider: Silent re-login successful.");
+        final String token = result['data']['token'];
+        final Map<String, dynamic> profile = result['data']['profile'];
+        await login(token, profile, _tempOfflinePassword!);
+        return true;
+      } else {
+        debugPrint("AuthProvider: Silent re-login failed: ${result['message']}");
+        return false;
+      }
+    } catch (e) {
+      debugPrint("AuthProvider: Silent re-login exception: $e");
+      return false;
+    }
+  }
+
   Future<void> syncAllData({bool forceRefresh = false}) async {
     final connectivityResult = await Connectivity().checkConnectivity();
-    if (connectivityResult == ConnectivityResult.none) {
+    if (connectivityResult.contains(ConnectivityResult.none)) {
       debugPrint("AuthProvider: Device is OFFLINE. Skipping sync.");
       return;
     }
 
+    // Prevent sync attempts if token is an offline placeholder
+    if (_jwtToken == null || _jwtToken!.startsWith("offline-session-")) {
+      debugPrint("AuthProvider: Skipping sync, session is offline or null.");
+      return;
+    }
+
     debugPrint("AuthProvider: Device is ONLINE. Starting delta sync.");
     final prefs = await SharedPreferences.getInstance();
-
-    // If 'forceRefresh' is true, sync all data by passing a null timestamp.
     final String? lastSync = forceRefresh ? null : prefs.getString(lastSyncTimestampKey);
-
-    // Record the time BEFORE the sync starts. This will be our new timestamp on success.
-    // Use UTC for consistency across timezones.
     final newSyncTimestamp = DateTime.now().toUtc().toIso8601String();
 
     final result = await _apiService.syncAllData(lastSyncTimestamp: lastSync);
 
     if (result['success']) {
       debugPrint("AuthProvider: Delta sync successful. Updating last sync timestamp.");
-      // On success, save the new timestamp for the next run.
       await prefs.setString(lastSyncTimestampKey, newSyncTimestamp);
       _lastSyncTimestamp = DateTime.parse(newSyncTimestamp);
 
-      // --- ADDED: After the first successful sync, set isFirstLogin to false ---
       if (_isFirstLogin) {
         await setIsFirstLogin(false);
         debugPrint("AuthProvider: First successful sync complete. isFirstLogin flag set to false.");
       }
-      // --- END ---
 
-      // After updating the DB, reload data from the cache into memory to update the UI.
       await _loadDataFromCache();
       notifyListeners();
     } else {
@@ -194,22 +267,31 @@ class AuthProvider with ChangeNotifier {
     }
   }
 
-  /// A dedicated method to refresh only the profile.
   Future<void> refreshProfile() async {
+    final connectivityResult = await Connectivity().checkConnectivity();
+    if (connectivityResult.contains(ConnectivityResult.none)) {
+      debugPrint("AuthProvider: Device is OFFLINE. Skipping profile refresh.");
+      return;
+    }
+    if (_jwtToken == null || _jwtToken!.startsWith("offline-session-")) {
+      debugPrint("AuthProvider: Skipping profile refresh, session is offline or null.");
+      return;
+    }
+
     final result = await _apiService.refreshProfile();
     if (result['success']) {
-      _profileData = result['data'];
-      // Persist the updated profile data
-      await _dbHelper.saveProfile(_profileData!);
-      final prefs = await SharedPreferences.getInstance();
-      await prefs.setString(profileDataKey, jsonEncode(_profileData));
-      notifyListeners();
+      await setProfileData(result['data']);
     }
   }
 
-  /// Loads all master data from the local cache using DatabaseHelper.
   Future<void> _loadDataFromCache() async {
-    _profileData = await _dbHelper.loadProfile();
+    final prefs = await SharedPreferences.getInstance();
+    final profileJson = prefs.getString(profileDataKey);
+    if (profileJson != null) {
+      _profileData = jsonDecode(profileJson);
+    } else {
+      _profileData = await _dbHelper.loadProfile();
+    }
     _allUsers = await _dbHelper.loadUsers();
     _tarballStations = await _dbHelper.loadTarballStations();
     _manualStations = await _dbHelper.loadManualStations();
@@ -222,49 +304,116 @@ class AuthProvider with ChangeNotifier {
     _airClients = await _dbHelper.loadAirClients();
     _airManualStations = await _dbHelper.loadAirManualStations();
     _states = await _dbHelper.loadStates();
-    // ADDED: Load new data types from the local database
     _appSettings = await _dbHelper.loadAppSettings();
     _parameterLimits = await _dbHelper.loadParameterLimits();
-    // --- ADDED: Load documents from the local database cache ---
     _documents = await _dbHelper.loadDocuments();
     _apiConfigs = await _dbHelper.loadApiConfigs();
     _ftpConfigs = await _dbHelper.loadFtpConfigs();
-    // --- ADDED: Load pending retry tasks from the database ---
     _pendingRetries = await _retryService.getPendingTasks();
     debugPrint("AuthProvider: All master data loaded from local DB cache.");
   }
 
-  // --- ADDED: A public method to allow the UI to refresh the pending tasks list ---
-  /// Refreshes the list of pending retry tasks from the local database.
   Future<void> refreshPendingTasks() async {
     _pendingRetries = await _retryService.getPendingTasks();
     notifyListeners();
   }
 
-  // --- Methods for UI interaction ---
-
-  /// Handles the login process, saving session data and triggering a full data sync.
-  Future<void> login(String token, Map<String, dynamic> profile) async {
+  Future<void> login(String token, Map<String, dynamic> profile, String password) async {
     _jwtToken = token;
     _userEmail = profile['email'];
-    _profileData = profile;
+    // --- MODIFIED: Cache password on successful ONLINE login ---
+    _tempOfflinePassword = 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(profile));
-    await _dbHelper.saveProfile(profile);
+    await prefs.setString(profileDataKey, jsonEncode(_profileData));
+    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");
+    }
 
     debugPrint('AuthProvider: Login successful. Session and profile persisted.');
-    // Perform a full refresh on login to ensure data is pristine.
     await syncAllData(forceRefresh: true);
   }
 
+  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) {
+        debugPrint("AuthProvider DEBUG: Offline login failed for $email because NO HASH was found in local storage.");
+        return false;
+      }
+
+      // 2. Verify the provided password against the stored hash.
+      debugPrint("AuthProvider: Verifying password against stored hash...");
+      final bool passwordMatches = await compute(verifyPassword, CheckPasswordParams(password, storedHash));
+
+      if (passwordMatches) {
+        debugPrint("AuthProvider: Offline password verification successful.");
+        // 3. Load profile data from local storage.
+        final Map<String, dynamic>? cachedProfile = await _dbHelper.loadProfileByEmail(email);
+        if (cachedProfile == null) {
+          debugPrint("AuthProvider DEBUG: Offline login failed because profile data was missing, even though password matched.");
+          return false;
+        }
+
+        // 4. Initialize session state from cached profile data.
+        _jwtToken = "offline-session-${DateTime.now().millisecondsSinceEpoch}";
+        _userEmail = email;
+
+        // --- MODIFIED: Cache the password on successful OFFLINE login ---
+        _tempOfflinePassword = password;
+
+        final Map<String, dynamic> profileWithToken = Map.from(cachedProfile);
+        profileWithToken['token'] = _jwtToken;
+        _profileData = profileWithToken;
+
+        final prefs = await SharedPreferences.getInstance();
+        await prefs.setString(tokenKey, _jwtToken!);
+        await prefs.setString(userEmailKey, _userEmail!);
+        await prefs.setString(profileDataKey, jsonEncode(_profileData));
+
+        await _loadDataFromCache();
+        notifyListeners();
+        return true;
+      } else {
+        debugPrint("AuthProvider DEBUG: Offline login failed because password did not match stored hash (Hash Mismatch).");
+        return false;
+      }
+    } catch (e) {
+      debugPrint("AuthProvider DEBUG: An unexpected error occurred during offline login process: $e");
+      return false;
+    }
+  }
+
   Future<void> setProfileData(Map<String, dynamic> data) async {
+    final String? existingToken = _profileData?['token'];
     _profileData = data;
+    if (_profileData != null && existingToken != null) {
+      _profileData!['token'] = existingToken;
+    }
+
     final prefs = await SharedPreferences.getInstance();
-    await prefs.setString(profileDataKey, jsonEncode(data));
-    await _dbHelper.saveProfile(data); // Also save to local DB
+    await prefs.setString(profileDataKey, jsonEncode(_profileData));
+    await _dbHelper.saveProfile(_profileData!); // Also save to local DB
     notifyListeners();
   }
 
@@ -282,6 +431,9 @@ class AuthProvider with ChangeNotifier {
     _profileData = null;
     _lastSyncTimestamp = null;
     _isFirstLogin = true;
+    // --- MODIFIED: Clear temp password on logout ---
+    _tempOfflinePassword = null;
+
     _allUsers = null;
     _tarballStations = null;
     _manualStations = null;
@@ -294,18 +446,14 @@ class AuthProvider with ChangeNotifier {
     _airClients = null;
     _airManualStations = null;
     _states = null;
-    // ADDED: Clear new data on logout
     _appSettings = null;
     _parameterLimits = null;
-    // --- ADDED: Clear documents list on logout ---
     _documents = null;
     _apiConfigs = null;
     _ftpConfigs = null;
-    // --- ADDED: Clear pending retry tasks on logout ---
     _pendingRetries = null;
 
     final prefs = await SharedPreferences.getInstance();
-    // MODIFIED: Removed keys individually for safer logout
     await prefs.remove(tokenKey);
     await prefs.remove(userEmailKey);
     await prefs.remove(profileDataKey);
@@ -319,4 +467,18 @@ class AuthProvider with ChangeNotifier {
   Future<Map<String, dynamic>> resetPassword(String email) {
     return _apiService.post('auth/forgot-password', {'email': email});
   }
+}
+
+class CheckPasswordParams {
+  final String password;
+  final String hash;
+  CheckPasswordParams(this.password, this.hash);
+}
+
+String hashPassword(String password) {
+  return BCrypt.hashpw(password, BCrypt.gensalt());
+}
+
+bool verifyPassword(CheckPasswordParams params) {
+  return BCrypt.checkpw(params.password, params.hash);
 }
\ No newline at end of file
diff --git a/lib/collapsible_sidebar.dart b/lib/collapsible_sidebar.dart
index 1296def..9827e35 100644
--- a/lib/collapsible_sidebar.dart
+++ b/lib/collapsible_sidebar.dart
@@ -43,117 +43,91 @@ class _CollapsibleSidebarState extends State<CollapsibleSidebar> {
   @override
   void initState() {
     super.initState();
+    // --- MODIFIED: Menu items now match the home pages ---
     _menuItems = [
+      // ====== AIR ======
       SidebarItem(
-        // Reverted to IconData for the top-level 'Air' category
         icon: Icons.cloud,
         label: "Air",
         isParent: true,
         children: [
-          // Added Manual sub-category for Air
           SidebarItem(
-            icon: Icons.handshake, // Example icon for Manual
+            icon: Icons.handshake,
             label: "Manual",
             isParent: true,
             children: [
-              SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/air/manual/dashboard'),
-              SidebarItem(icon: Icons.edit_note, label: "Manual Sampling", route: '/air/manual/manual-sampling'),
-              SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/air/manual/report'),
+              SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/air/manual/info'),
+              SidebarItem(icon: Icons.construction, label: "Installation", route: '/air/manual/installation'),
+              SidebarItem(icon: Icons.inventory_2, label: "Collection", route: '/air/manual/collection'),
               SidebarItem(icon: Icons.article, label: "Data Log", route: '/air/manual/data-log'),
-              SidebarItem(icon: Icons.image, label: "Image Request", route: '/air/manual/image-request'),
             ],
           ),
           SidebarItem(
               icon: Icons.trending_up, label: "Continuous", isParent: true, children: [
-            SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/air/continuous/dashboard'),
-            SidebarItem(icon: Icons.info, label: "Overview", route: '/air/continuous/overview'),
-            SidebarItem(icon: Icons.input, label: "Entry", route: '/air/continuous/entry'),
-            SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/air/continuous/report'),
+            SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/air/continuous/info'),
           ]),
           SidebarItem(
               icon: Icons.search, label: "Investigative", isParent: true, children: [
-            SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/air/investigative/dashboard'),
-            SidebarItem(icon: Icons.info, label: "Overview", route: '/air/investigative/overview'),
-            SidebarItem(icon: Icons.input, label: "Entry", route: '/air/investigative/entry'),
-            SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/air/investigative/report'),
+            SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/air/investigative/info'),
           ]),
         ],
       ),
+      // ====== RIVER ======
       SidebarItem(
-        // Reverted to IconData for the top-level 'River' category
         icon: Icons.water,
         label: "River",
         isParent: true,
         children: [
-          // Added Manual sub-category for River
           SidebarItem(
-            icon: Icons.handshake, // Example icon for Manual
+            icon: Icons.handshake,
             label: "Manual",
             isParent: true,
             children: [
-              SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/river/manual/dashboard'),
+              SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/river/manual/info'),
               SidebarItem(icon: Icons.pin_drop, label: "In-Situ Sampling", route: '/river/manual/in-situ'),
-              SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/river/manual/report'),
               SidebarItem(icon: Icons.date_range, label: "Triennial Sampling", route: '/river/manual/triennial'),
               SidebarItem(icon: Icons.article, label: "Data Log", route: '/river/manual/data-log'),
-              SidebarItem(icon: Icons.image, label: "Image Request", route: '/river/manual/image-request'),
             ],
           ),
           SidebarItem(
               icon: Icons.trending_up, label: "Continuous", isParent: true, children: [
-            SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/river/continuous/dashboard'),
-            SidebarItem(icon: Icons.info, label: "Overview", route: '/river/continuous/overview'),
-            SidebarItem(icon: Icons.input, label: "Entry", route: '/river/continuous/entry'),
-            SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/river/continuous/report'),
+            SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/river/continuous/info'),
           ]),
           SidebarItem(
               icon: Icons.search, label: "Investigative", isParent: true, children: [
-            SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/river/investigative/dashboard'),
-            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'),
+            SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/river/investigative/info'),
           ]),
         ],
       ),
+      // ====== MARINE ======
       SidebarItem(
-        // Reverted to IconData for the top-level 'Marine' category
         icon: Icons.sailing,
         label: "Marine",
         isParent: true,
         children: [
-          // Added Manual sub-category for Marine
           SidebarItem(
-            icon: Icons.handshake, // Example icon for Manual
+            icon: Icons.handshake,
             label: "Manual",
             isParent: true,
             children: [
-              SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/marine/manual/dashboard'),
               SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/marine/manual/info'),
               SidebarItem(icon: Icons.assignment, label: "Pre-Sampling", route: '/marine/manual/pre-sampling'),
               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.receipt_long, label: "Report", route: '/marine/manual/report'),
               SidebarItem(icon: Icons.article, label: "Data Log", route: '/marine/manual/data-log'),
-              SidebarItem(icon: Icons.image, label: "Image Request", route: '/marine/manual/image-request'),
             ],
           ),
           SidebarItem(
               icon: Icons.trending_up, label: "Continuous", isParent: true, children: [
-            SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/marine/continuous/dashboard'),
-            SidebarItem(icon: Icons.info, label: "Overview", route: '/marine/continuous/overview'),
-            SidebarItem(icon: Icons.input, label: "Entry", route: '/marine/continuous/entry'),
-            SidebarItem(icon: Icons.receipt_long, label: "Report", route: '/marine/continuous/report'),
+            SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/marine/continuous/info'),
           ]),
           SidebarItem(
               icon: Icons.search, label: "Investigative", isParent: true, children: [
-            SidebarItem(icon: Icons.dashboard, label: "Dashboard", route: '/marine/investigative/dashboard'),
-            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'),
+            SidebarItem(icon: Icons.description, label: "Info Centre Document", route: '/marine/investigative/info'),
           ]),
         ],
       ),
-      // Added Settings menu item
+      // ====== SETTINGS ======
       SidebarItem(icon: Icons.settings, label: "Settings", route: '/settings'),
     ];
   }
@@ -202,8 +176,7 @@ class _CollapsibleSidebarState extends State<CollapsibleSidebar> {
   Widget _buildExpandableNavItem(SidebarItem item) {
     if (item.children == null || item.children!.isEmpty) {
       // This case handles a top-level item that is NOT a parent,
-      // but if you have such an item, it should probably go through _buildNavItem directly.
-      // For this structure, all top-level items are parents.
+      // like the "Settings" item.
       return _buildNavItem(item.icon, item.label, item.route ?? '', isTopLevel: true, imagePath: item.imagePath);
     }
 
@@ -298,4 +271,4 @@ class _CollapsibleSidebarState extends State<CollapsibleSidebar> {
       ),
     );
   }
-}
+}
\ No newline at end of file
diff --git a/lib/main.dart b/lib/main.dart
index 8fc6e00..0bac92e 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -124,24 +124,63 @@ void main() async {
 }
 
 void setupServices(TelegramService telegramService) {
+  // Initial alert processing on startup (delayed)
   Future.delayed(const Duration(seconds: 5), () {
     debugPrint("[Main] Performing initial alert queue processing on app start.");
     telegramService.processAlertQueue();
   });
 
-  Connectivity().onConnectivityChanged.listen((List<ConnectivityResult> results) {
-    if (results.contains(ConnectivityResult.mobile) || results.contains(ConnectivityResult.wifi)) {
-      debugPrint("[Main] Internet connection detected. Triggering alert queue processing.");
-      telegramService.processAlertQueue();
-    } else {
-      debugPrint("[Main] Internet connection lost.");
-    }
-  });
+  // Connectivity listener moved to RootApp to access AuthProvider context.
 }
 
-class RootApp extends StatelessWidget {
+// --- START: MODIFIED RootApp ---
+class RootApp extends StatefulWidget {
   const RootApp({super.key});
 
+  @override
+  State<RootApp> createState() => _RootAppState();
+}
+
+class _RootAppState extends State<RootApp> {
+
+  @override
+  void initState() {
+    super.initState();
+    _initializeConnectivityListener();
+    _performInitialSessionCheck();
+  }
+
+  /// Initial check when app loads to see if we need to transition from offline to online.
+  void _performInitialSessionCheck() async {
+    // Wait a moment for providers to be fully available.
+    await Future.delayed(const Duration(milliseconds: 100));
+    if (mounted) {
+      Provider.of<AuthProvider>(context, listen: false).checkAndTransitionToOnlineSession();
+    }
+  }
+
+  /// Listens for connectivity changes to trigger auto-relogin or queue processing.
+  void _initializeConnectivityListener() {
+    Connectivity().onConnectivityChanged.listen((List<ConnectivityResult> results) {
+      if (!results.contains(ConnectivityResult.none)) {
+        debugPrint("[Main] Internet connection detected.");
+        if (mounted) {
+          // Access services from provider context
+          final authProvider = Provider.of<AuthProvider>(context, listen: false);
+          final telegramService = Provider.of<TelegramService>(context, listen: false);
+
+          // Attempt to auto-relogin if necessary
+          authProvider.checkAndTransitionToOnlineSession();
+
+          // Process alert queue
+          telegramService.processAlertQueue();
+        }
+      } else {
+        debugPrint("[Main] Internet connection lost.");
+      }
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     return Consumer<AuthProvider>(
@@ -241,7 +280,7 @@ class RootApp extends StatelessWidget {
             '/marine/manual/in-situ': (context) => marineManualInSituSampling.MarineInSituSampling(),
             '/marine/manual/tarball': (context) => const TarballSamplingStep1(),
             '/marine/manual/report': (context) => marineManualReport.MarineManualReport(),
-            '/marine/manual/data-log': (context) => marineManualDataStatusLog.MarineManualDataStatusLog(),
+            //'/marine/manual/data-log': (context) => marineManualDataStatusLog.MarineManualDataStatusLog(), // This is handled in onGenerateRoute
             '/marine/manual/image-request': (context) => marineManualImageRequest.MarineManualImageRequest(),
 
             // Marine Continuous
@@ -261,6 +300,7 @@ class RootApp extends StatelessWidget {
     );
   }
 }
+// --- END: MODIFIED RootApp ---
 
 class SplashScreen extends StatelessWidget {
   const SplashScreen({super.key});
@@ -273,7 +313,7 @@ class SplashScreen extends StatelessWidget {
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
             Image.asset(
-              'assets/icon4.png',
+              'assets/icon4.png', // Ensure this asset exists
               height: 360,
               width: 360,
             ),
diff --git a/lib/models/in_situ_sampling_data.dart b/lib/models/in_situ_sampling_data.dart
index 6ffd109..44c3b47 100644
--- a/lib/models/in_situ_sampling_data.dart
+++ b/lib/models/in_situ_sampling_data.dart
@@ -68,13 +68,14 @@ class InSituSamplingData {
   String? submissionMessage;
   String? reportId;
 
-  // REPAIRED: Added a constructor to accept initial values.
   InSituSamplingData({
     this.samplingDate,
     this.samplingTime,
   });
 
-  // --- ADDED: Factory constructor to create a new instance from a map ---
+  /// Creates an InSituSamplingData object from a JSON map.
+  /// This is critical for the offline retry mechanism. The keys used here MUST perfectly
+  /// match the keys used in the `toDbJson()` method to ensure data integrity.
   factory InSituSamplingData.fromJson(Map<String, dynamic> json) {
     double? doubleFromJson(dynamic value) {
       if (value is num) return value.toDouble();
@@ -88,62 +89,70 @@ class InSituSamplingData {
       return null;
     }
 
-    // Helper to create a File object from a path string
     File? fileFromPath(dynamic path) {
       return (path is String && path.isNotEmpty) ? File(path) : null;
     }
 
-    return InSituSamplingData()
-      ..firstSamplerName = json['first_sampler_name']
-      ..firstSamplerUserId = intFromJson(json['first_sampler_user_id'])
-      ..secondSampler = json['secondSampler']
-      ..samplingDate = json['man_date']
-      ..samplingTime = json['man_time']
-      ..samplingType = json['man_type']
-      ..sampleIdCode = json['man_sample_id_code']
-      ..selectedStateName = json['selectedStateName']
-      ..selectedCategoryName = json['selectedCategoryName']
-      ..selectedStation = json['selectedStation']
-      ..stationLatitude = json['stationLatitude']
-      ..stationLongitude = json['stationLongitude']
-      ..currentLatitude = json['man_current_latitude']?.toString()
-      ..currentLongitude = json['man_current_longitude']?.toString()
-      ..distanceDifferenceInKm = doubleFromJson(json['man_distance_difference'])
-      ..distanceDifferenceRemarks = json['man_distance_difference_remarks']
-      ..weather = json['man_weather']
-      ..tideLevel = json['man_tide_level']
-      ..seaCondition = json['man_sea_condition']
-      ..eventRemarks = json['man_event_remark']
-      ..labRemarks = json['man_lab_remark']
-      ..sondeId = json['man_sondeID']
-      ..dataCaptureDate = json['data_capture_date']
-      ..dataCaptureTime = json['data_capture_time']
-      ..oxygenConcentration = doubleFromJson(json['man_oxygen_conc'])
-      ..oxygenSaturation = doubleFromJson(json['man_oxygen_sat'])
-      ..ph = doubleFromJson(json['man_ph'])
-      ..salinity = doubleFromJson(json['man_salinity'])
-      ..electricalConductivity = doubleFromJson(json['man_conductivity'])
-      ..temperature = doubleFromJson(json['man_temperature'])
-      ..tds = doubleFromJson(json['man_tds'])
-      ..turbidity = doubleFromJson(json['man_turbidity'])
-      ..tss = doubleFromJson(json['man_tss'])
-      ..batteryVoltage = doubleFromJson(json['man_battery_volt'])
-      ..optionalRemark1 = json['man_optional_photo_01_remarks']
-      ..optionalRemark2 = json['man_optional_photo_02_remarks']
-      ..optionalRemark3 = json['man_optional_photo_03_remarks']
-      ..optionalRemark4 = json['man_optional_photo_04_remarks']
-      ..leftLandViewImage = fileFromPath(json['man_left_side_land_view'])
-      ..rightLandViewImage = fileFromPath(json['man_right_side_land_view'])
-      ..waterFillingImage = fileFromPath(json['man_filling_water_into_sample_bottle'])
-      ..seawaterColorImage = fileFromPath(json['man_seawater_in_clear_glass_bottle'])
-      ..phPaperImage = fileFromPath(json['man_examine_preservative_ph_paper'])
-      ..optionalImage1 = fileFromPath(json['man_optional_photo_01'])
-      ..optionalImage2 = fileFromPath(json['man_optional_photo_02'])
-      ..optionalImage3 = fileFromPath(json['man_optional_photo_03'])
-      ..optionalImage4 = fileFromPath(json['man_optional_photo_04']);
+    final data = InSituSamplingData();
+
+    // START FIX: Aligned all keys to perfectly match the toDbJson() method and added backward compatibility.
+    data.firstSamplerName = json['first_sampler_name'];
+    data.firstSamplerUserId = intFromJson(json['first_sampler_user_id']);
+    data.secondSampler = json['secondSampler'] ?? json['second_sampler'];
+    data.samplingDate = json['sampling_date'] ?? json['man_date'];
+    data.samplingTime = json['sampling_time'] ?? json['man_time'];
+    data.samplingType = json['sampling_type'];
+    data.sampleIdCode = json['sample_id_code'];
+    data.selectedStateName = json['selected_state_name'];
+    data.selectedCategoryName = json['selected_category_name'];
+    data.selectedStation = json['selectedStation'];
+    data.stationLatitude = json['station_latitude'];
+    data.stationLongitude = json['station_longitude'];
+    data.currentLatitude = json['current_latitude']?.toString();
+    data.currentLongitude = json['current_longitude']?.toString();
+    data.distanceDifferenceInKm = doubleFromJson(json['distance_difference_in_km']);
+    data.distanceDifferenceRemarks = json['distance_difference_remarks'];
+    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['man_optional_photo_01_remarks'];
+    data.optionalRemark2 = json['man_optional_photo_02_remarks'];
+    data.optionalRemark3 = json['man_optional_photo_03_remarks'];
+    data.optionalRemark4 = json['man_optional_photo_04_remarks'];
+    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']);
+    data.submissionStatus = json['submission_status'];
+    data.submissionMessage = json['submission_message'];
+    data.reportId = json['report_id']?.toString();
+
+    // Image paths are added by LocalStorageService, not toDbJson, so they are read separately.
+    data.leftLandViewImage = fileFromPath(json['man_left_side_land_view']);
+    data.rightLandViewImage = fileFromPath(json['man_right_side_land_view']);
+    data.waterFillingImage = fileFromPath(json['man_filling_water_into_sample_bottle']);
+    data.seawaterColorImage = fileFromPath(json['man_seawater_in_clear_glass_bottle']);
+    data.phPaperImage = fileFromPath(json['man_examine_preservative_ph_paper']);
+    data.optionalImage1 = fileFromPath(json['man_optional_photo_01']);
+    data.optionalImage2 = fileFromPath(json['man_optional_photo_02']);
+    data.optionalImage3 = fileFromPath(json['man_optional_photo_03']);
+    data.optionalImage4 = fileFromPath(json['man_optional_photo_04']);
+    // END FIX
+
+    return data;
   }
 
-  /// Generates a formatted Telegram alert message for successful submissions.
   String generateTelegramAlertMessage({required bool isDataOnly}) {
     final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
     final stationName = selectedStation?['man_station_name'] ?? 'N/A';
@@ -172,24 +181,32 @@ class InSituSamplingData {
     return buffer.toString();
   }
 
-  /// Converts the data model into a Map<String, String> for the API form data.
   Map<String, String> toApiFormData() {
     final Map<String, String> map = {};
 
-    // Helper to add non-null values to the map
     void add(String key, dynamic value) {
-      if (value != null && value.toString().isNotEmpty) {
-        map[key] = value.toString();
+      if (value != null) {
+        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;
+        }
       }
     }
 
-    // --- Required fields that were missing or incorrect ---
     add('station_id', selectedStation?['station_id']);
     add('man_date', samplingDate);
     add('man_time', samplingTime);
     add('first_sampler_user_id', firstSamplerUserId);
-
-    // --- Other Step 1 Data ---
     add('man_second_sampler_id', secondSampler?['user_id']);
     add('man_type', samplingType);
     add('man_sample_id_code', sampleIdCode);
@@ -197,8 +214,6 @@ class InSituSamplingData {
     add('man_current_longitude', currentLongitude);
     add('man_distance_difference', distanceDifferenceInKm);
     add('man_distance_difference_remarks', distanceDifferenceRemarks);
-
-    // --- Step 2 Data ---
     add('man_weather', weather);
     add('man_tide_level', tideLevel);
     add('man_sea_condition', seaCondition);
@@ -208,8 +223,6 @@ class InSituSamplingData {
     add('man_optional_photo_02_remarks', optionalRemark2);
     add('man_optional_photo_03_remarks', optionalRemark3);
     add('man_optional_photo_04_remarks', optionalRemark4);
-
-    // --- Step 3 Data ---
     add('man_sondeID', sondeId);
     add('data_capture_date', dataCaptureDate);
     add('data_capture_time', dataCaptureTime);
@@ -223,8 +236,6 @@ class InSituSamplingData {
     add('man_turbidity', turbidity);
     add('man_tss', tss);
     add('man_battery_volt', batteryVoltage);
-
-    // --- Human-readable fields for server-side alerts ---
     add('first_sampler_name', firstSamplerName);
     add('man_station_code', selectedStation?['man_station_code']);
     add('man_station_name', selectedStation?['man_station_name']);
@@ -232,7 +243,6 @@ class InSituSamplingData {
     return map;
   }
 
-  /// Converts the image properties into a Map<String, File?> for the multipart API request.
   Map<String, File?> toApiImageFiles() {
     return {
       'man_left_side_land_view': leftLandViewImage,
@@ -247,19 +257,20 @@ class InSituSamplingData {
     };
   }
 
-  /// Creates a single JSON object with all submission data, mimicking 'db.json'.
+  /// Creates a single JSON object with all submission data for offline storage.
+  /// The keys here are the single source of truth for the offline data format.
   Map<String, dynamic> toDbJson() {
     return {
       'first_sampler_name': firstSamplerName,
       'first_sampler_user_id': firstSamplerUserId,
-      'second_sampler': secondSampler,
+      'secondSampler': secondSampler,
       'sampling_date': samplingDate,
       'sampling_time': samplingTime,
       'sampling_type': samplingType,
       'sample_id_code': sampleIdCode,
       'selected_state_name': selectedStateName,
       'selected_category_name': selectedCategoryName,
-      'selected_station': selectedStation,
+      'selectedStation': selectedStation,
       'station_latitude': stationLatitude,
       'station_longitude': stationLongitude,
       'current_latitude': currentLatitude,
@@ -271,6 +282,10 @@ class InSituSamplingData {
       'sea_condition': seaCondition,
       'event_remarks': eventRemarks,
       'lab_remarks': labRemarks,
+      'man_optional_photo_01_remarks': optionalRemark1,
+      'man_optional_photo_02_remarks': optionalRemark2,
+      'man_optional_photo_03_remarks': optionalRemark3,
+      'man_optional_photo_04_remarks': optionalRemark4,
       'sonde_id': sondeId,
       'data_capture_date': dataCaptureDate,
       'data_capture_time': dataCaptureTime,
@@ -289,48 +304,4 @@ class InSituSamplingData {
       'report_id': reportId,
     };
   }
-
-  /// Creates a JSON object for basic form info, mimicking 'basic_form.json'.
-  Map<String, dynamic> toBasicFormJson() {
-    return {
-      'tech_name': firstSamplerName,
-      'sampler_2ndname': secondSampler?['user_name'],
-      'sample_date': samplingDate,
-      'sample_time': samplingTime,
-      'sampling_type': samplingType,
-      'sample_state': selectedStateName,
-      'station_id': selectedStation?['man_station_code'],
-      'station_latitude': stationLatitude,
-      'station_longitude': stationLongitude,
-      'latitude': currentLatitude,
-      'longitude': currentLongitude,
-      'sample_id': sampleIdCode,
-    };
-  }
-
-  /// Creates a JSON object for sensor readings, mimicking 'reading.json'.
-  Map<String, dynamic> toReadingJson() {
-    return {
-      'do_mgl': oxygenConcentration,
-      'do_sat': oxygenSaturation,
-      'ph': ph,
-      'salinity': salinity,
-      'temperature': temperature,
-      'turbidity': turbidity,
-      'tds': tds,
-      'electric_conductivity': electricalConductivity,
-      'flowrate': null, // This is not collected in marine in-situ
-      'date_sampling_reading': dataCaptureDate,
-      'time_sampling_reading': dataCaptureTime,
-    };
-  }
-
-  /// Creates a JSON object for manual info, mimicking 'manual_info.json'.
-  Map<String, dynamic> toManualInfoJson() {
-    return {
-      'weather': weather,
-      'remarks_event': eventRemarks,
-      'remarks_lab': labRemarks,
-    };
-  }
 }
\ No newline at end of file
diff --git a/lib/models/river_in_situ_sampling_data.dart b/lib/models/river_in_situ_sampling_data.dart
index 12ee4c9..6010b00 100644
--- a/lib/models/river_in_situ_sampling_data.dart
+++ b/lib/models/river_in_situ_sampling_data.dart
@@ -86,7 +86,6 @@ class RiverInSituSamplingData {
       return (path is String && path.isNotEmpty) ? File(path) : null;
     }
 
-    // FIX: Robust helper functions for parsing numerical values
     double? doubleFromJson(dynamic value) {
       if (value is num) return value.toDouble();
       if (value is String) return double.tryParse(value);
@@ -99,62 +98,63 @@ class RiverInSituSamplingData {
       return null;
     }
 
+    // --- START: MODIFIED FOR CONSISTENT SERIALIZATION ---
+    // Keys now match toMap() for reliability, with fallback to old API keys for backward compatibility.
     return RiverInSituSamplingData()
-      ..firstSamplerName = json['first_sampler_name']
-    // MODIFIED THIS LINE TO USE THE HELPER FUNCTION
-      ..firstSamplerUserId = intFromJson(json['first_sampler_user_id'])
+      ..firstSamplerName = json['firstSamplerName'] ?? json['first_sampler_name']
+      ..firstSamplerUserId = intFromJson(json['firstSamplerUserId'] ?? json['first_sampler_user_id'])
       ..secondSampler = json['secondSampler']
-      ..samplingDate = json['r_man_date']
-      ..samplingTime = json['r_man_time']
-      ..samplingType = json['r_man_type']
-      ..sampleIdCode = json['r_man_sample_id_code']
+      ..samplingDate = json['samplingDate'] ?? json['r_man_date']
+      ..samplingTime = json['samplingTime'] ?? json['r_man_time']
+      ..samplingType = json['samplingType'] ?? json['r_man_type']
+      ..sampleIdCode = json['sampleIdCode'] ?? json['r_man_sample_id_code']
       ..selectedStateName = json['selectedStateName']
       ..selectedCategoryName = json['selectedCategoryName']
       ..selectedStation = json['selectedStation']
       ..stationLatitude = json['stationLatitude']
       ..stationLongitude = json['stationLongitude']
-      ..currentLatitude = json['r_man_current_latitude']?.toString()
-      ..currentLongitude = json['r_man_current_longitude']?.toString()
-      ..distanceDifferenceInKm = doubleFromJson(json['r_man_distance_difference'])
-      ..distanceDifferenceRemarks = json['r_man_distance_difference_remarks']
-      ..weather = json['r_man_weather']
-      ..eventRemarks = json['r_man_event_remark']
-      ..labRemarks = json['r_man_lab_remark']
-      ..sondeId = json['r_man_sondeID']
-      ..dataCaptureDate = json['data_capture_date']
-      ..dataCaptureTime = json['data_capture_time']
-    // FIX: Apply doubleFromJson helper to all numerical fields
-      ..oxygenConcentration = doubleFromJson(json['r_man_oxygen_conc'])
-      ..oxygenSaturation = doubleFromJson(json['r_man_oxygen_sat'])
-      ..ph = doubleFromJson(json['r_man_ph'])
-      ..salinity = doubleFromJson(json['r_man_salinity'])
-      ..electricalConductivity = doubleFromJson(json['r_man_conductivity'])
-      ..temperature = doubleFromJson(json['r_man_temperature'])
-      ..tds = doubleFromJson(json['r_man_tds'])
-      ..turbidity = doubleFromJson(json['r_man_turbidity'])
-      ..ammonia = doubleFromJson(json['r_man_ammonia']) // MODIFIED: Replaced tss with ammonia
-      ..batteryVoltage = doubleFromJson(json['r_man_battery_volt'])
-    // END FIX
-      ..optionalRemark1 = json['r_man_optional_photo_01_remarks']
-      ..optionalRemark2 = json['r_man_optional_photo_02_remarks']
-      ..optionalRemark3 = json['r_man_optional_photo_03_remarks']
-      ..optionalRemark4 = json['r_man_optional_photo_04_remarks']
-      ..backgroundStationImage = fileFromJson(json['r_man_background_station'])
-      ..upstreamRiverImage = fileFromJson(json['r_man_upstream_river'])
-      ..downstreamRiverImage = fileFromJson(json['r_man_downstream_river'])
-      ..sampleTurbidityImage = fileFromJson(json['r_man_sample_turbidity'])
-      ..optionalImage1 = fileFromJson(json['r_man_optional_photo_01'])
-      ..optionalImage2 = fileFromJson(json['r_man_optional_photo_02'])
-      ..optionalImage3 = fileFromJson(json['r_man_optional_photo_03'])
-      ..optionalImage4 = fileFromJson(json['r_man_optional_photo_04'])
-    // ADDED: Flowrate fields from JSON
-      ..flowrateMethod = json['r_man_flowrate_method']
-    // FIX: Apply doubleFromJson helper to all new numerical flowrate fields
-      ..flowrateSurfaceDrifterHeight = doubleFromJson(json['r_man_flowrate_sd_height'])
-      ..flowrateSurfaceDrifterDistance = doubleFromJson(json['r_man_flowrate_sd_distance'])
-      ..flowrateSurfaceDrifterTimeFirst = json['r_man_flowrate_sd_time_first']
-      ..flowrateSurfaceDrifterTimeLast = json['r_man_flowrate_sd_time_last']
-      ..flowrateValue = doubleFromJson(json['r_man_flowrate_value']);
+      ..currentLatitude = (json['currentLatitude'] ?? json['r_man_current_latitude'])?.toString()
+      ..currentLongitude = (json['currentLongitude'] ?? json['r_man_current_longitude'])?.toString()
+      ..distanceDifferenceInKm = doubleFromJson(json['distanceDifferenceInKm'] ?? json['r_man_distance_difference'])
+      ..distanceDifferenceRemarks = json['distanceDifferenceRemarks'] ?? json['r_man_distance_difference_remarks']
+      ..weather = json['weather'] ?? json['r_man_weather']
+      ..eventRemarks = json['eventRemarks'] ?? json['r_man_event_remark']
+      ..labRemarks = json['labRemarks'] ?? json['r_man_lab_remark']
+      ..sondeId = json['sondeId'] ?? json['r_man_sondeID']
+      ..dataCaptureDate = json['dataCaptureDate'] ?? json['data_capture_date']
+      ..dataCaptureTime = json['dataCaptureTime'] ?? json['data_capture_time']
+      ..oxygenConcentration = doubleFromJson(json['oxygenConcentration'] ?? json['r_man_oxygen_conc'])
+      ..oxygenSaturation = doubleFromJson(json['oxygenSaturation'] ?? json['r_man_oxygen_sat'])
+      ..ph = doubleFromJson(json['ph'] ?? json['r_man_ph'])
+      ..salinity = doubleFromJson(json['salinity'] ?? json['r_man_salinity'])
+      ..electricalConductivity = doubleFromJson(json['electricalConductivity'] ?? json['r_man_conductivity'])
+      ..temperature = doubleFromJson(json['temperature'] ?? json['r_man_temperature'])
+      ..tds = doubleFromJson(json['tds'] ?? json['r_man_tds'])
+      ..turbidity = doubleFromJson(json['turbidity'] ?? json['r_man_turbidity'])
+      ..ammonia = doubleFromJson(json['ammonia'] ?? json['r_man_ammonia'])
+      ..batteryVoltage = doubleFromJson(json['batteryVoltage'] ?? json['r_man_battery_volt'])
+      ..optionalRemark1 = json['optionalRemark1'] ?? json['r_man_optional_photo_01_remarks']
+      ..optionalRemark2 = json['optionalRemark2'] ?? json['r_man_optional_photo_02_remarks']
+      ..optionalRemark3 = json['optionalRemark3'] ?? json['r_man_optional_photo_03_remarks']
+      ..optionalRemark4 = json['optionalRemark4'] ?? json['r_man_optional_photo_04_remarks']
+      ..backgroundStationImage = fileFromJson(json['backgroundStationImage'] ?? json['r_man_background_station'])
+      ..upstreamRiverImage = fileFromJson(json['upstreamRiverImage'] ?? json['r_man_upstream_river'])
+      ..downstreamRiverImage = fileFromJson(json['downstreamRiverImage'] ?? json['r_man_downstream_river'])
+      ..sampleTurbidityImage = fileFromJson(json['sampleTurbidityImage'] ?? json['r_man_sample_turbidity'])
+      ..optionalImage1 = fileFromJson(json['optionalImage1'] ?? json['r_man_optional_photo_01'])
+      ..optionalImage2 = fileFromJson(json['optionalImage2'] ?? json['r_man_optional_photo_02'])
+      ..optionalImage3 = fileFromJson(json['optionalImage3'] ?? json['r_man_optional_photo_03'])
+      ..optionalImage4 = fileFromJson(json['optionalImage4'] ?? json['r_man_optional_photo_04'])
+      ..flowrateMethod = json['flowrateMethod'] ?? json['r_man_flowrate_method']
+      ..flowrateSurfaceDrifterHeight = doubleFromJson(json['flowrateSurfaceDrifterHeight'] ?? json['r_man_flowrate_sd_height'])
+      ..flowrateSurfaceDrifterDistance = doubleFromJson(json['flowrateSurfaceDrifterDistance'] ?? json['r_man_flowrate_sd_distance'])
+      ..flowrateSurfaceDrifterTimeFirst = json['flowrateSurfaceDrifterTimeFirst'] ?? json['r_man_flowrate_sd_time_first']
+      ..flowrateSurfaceDrifterTimeLast = json['flowrateSurfaceDrifterTimeLast'] ?? json['r_man_flowrate_sd_time_last']
+      ..flowrateValue = doubleFromJson(json['flowrateValue'] ?? json['r_man_flowrate_value'])
+      ..submissionStatus = json['submissionStatus']
+      ..submissionMessage = json['submissionMessage']
+      ..reportId = json['reportId']?.toString();
+    // --- END: MODIFIED FOR CONSISTENT SERIALIZATION ---
   }
 
 
diff --git a/lib/screens/login.dart b/lib/screens/login.dart
index fad1776..c919485 100644
--- a/lib/screens/login.dart
+++ b/lib/screens/login.dart
@@ -1,6 +1,10 @@
+// lib/screens/login.dart
+
+import 'dart:async'; // Import for TimeoutException
+
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
-import 'package:connectivity_plus/connectivity_plus.dart';
+import 'package:connectivity_plus/connectivity_plus.dart'; // Keep for potential future use, though not strictly necessary for the new logic
 
 import 'package:environment_monitoring_app/services/api_service.dart';
 import 'package:environment_monitoring_app/auth_provider.dart';
@@ -17,7 +21,6 @@ class _LoginScreenState extends State<LoginScreen> {
   final _formKey = GlobalKey<FormState>();
   final TextEditingController _emailController = TextEditingController();
   final TextEditingController _passwordController = TextEditingController();
-  // FIX: Removed direct instantiation of ApiService
   bool _isLoading = false;
   String _errorMessage = '';
 
@@ -39,60 +42,75 @@ class _LoginScreenState extends State<LoginScreen> {
     });
 
     final auth = Provider.of<AuthProvider>(context, listen: false);
-    // FIX: Retrieve ApiService from the Provider tree
     final apiService = Provider.of<ApiService>(context, listen: false);
+    final String email = _emailController.text.trim();
+    final String password = _passwordController.text.trim();
 
+    // --- START: MODIFIED Internet-First Strategy with Improved Fallback ---
+    try {
+      // --- Attempt 1: Online Login ---
+      debugPrint("Login attempt: Trying online authentication...");
+      final Map<String, dynamic> result = await apiService
+          .login(email, password)
+          .timeout(const Duration(seconds: 10));
+
+      if (result['success'] == true) {
+        // --- Online Success ---
+        final String token = result['data']['token'];
+        final Map<String, dynamic> profile = result['data']['profile'];
+        await auth.login(token, profile, password);
+
+        if (auth.isFirstLogin) {
+          await auth.setIsFirstLogin(false);
+        }
 
-    // --- Offline Check for First Login ---
-    if (auth.isFirstLogin) {
-      final connectivityResult = await Connectivity().checkConnectivity();
-      if (connectivityResult == ConnectivityResult.none) {
         if (!mounted) return;
+        Navigator.of(context).pushReplacement(
+          MaterialPageRoute(builder: (context) => const HomePage()),
+        );
+      } else {
+        // --- Online Failure (API Error) ---
         setState(() {
-          _isLoading = false;
-          _errorMessage = 'An internet connection is required for the first login to sync initial data.';
+          _errorMessage = result['message'] ?? 'Invalid email or password.';
         });
         _showSnackBar(_errorMessage, isError: true);
-        return;
+      }
+    } on TimeoutException catch (_) {
+      // --- Online Failure (Timeout) ---
+      debugPrint("Login attempt: Online request timed out after 10 seconds. Triggering offline fallback.");
+      _showSnackBar("Slow connection detected. Trying offline login...", isError: true);
+      await _attemptOfflineLogin(auth, email, password);
+    } catch (e) {
+      // --- Online Failure (Other Network Error, e.g., SocketException) ---
+      debugPrint("Login attempt: Network error ($e). Triggering offline fallback immediately.");
+      _showSnackBar("Connection failed. Trying offline login...", isError: true);
+      // FIX: Removed the unreliable connectivity check. Treat all exceptions here as a reason to try offline.
+      await _attemptOfflineLogin(auth, email, password);
+    } finally {
+      if (mounted) {
+        setState(() {
+          _isLoading = false;
+        });
       }
     }
+    // --- END: MODIFIED Internet-First Strategy ---
+  }
 
-    // --- API Call ---
-    final Map<String, dynamic> result = await apiService.login( // FIX: Use retrieved instance
-      _emailController.text.trim(),
-      _passwordController.text.trim(),
-    );
+  /// Helper function to perform offline validation and update UI.
+  Future<void> _attemptOfflineLogin(AuthProvider auth, String email, String password) async {
+    final bool offlineSuccess = await auth.loginOffline(email, password);
 
-    if (!mounted) return;
-
-    if (result['success'] == true) {
-      // --- Update AuthProvider ---
-      final String token = result['data']['token'];
-      // CORRECTED: The API now returns a 'profile' object on login, not 'user'.
-      final Map<String, dynamic> profile = result['data']['profile'];
-
-      // The login method in AuthProvider now handles setting the token, profile,
-      // and triggering the full data sync.
-      await auth.login(token, profile);
-
-      if (auth.isFirstLogin) {
-        await auth.setIsFirstLogin(false);
+    if (mounted) {
+      if (offlineSuccess) {
+        Navigator.of(context).pushReplacement(
+          MaterialPageRoute(builder: (context) => const HomePage()),
+        );
+      } else {
+        setState(() {
+          _errorMessage = "Offline login failed. Check credentials or connect to internet to sync.";
+        });
+        _showSnackBar(_errorMessage, isError: true);
       }
-
-      if (!mounted) return;
-
-      // Navigate to the home screen
-      Navigator.of(context).pushReplacement(
-        MaterialPageRoute(builder: (context) => const HomePage()),
-      );
-
-    } else {
-      // Login failed, show error message
-      setState(() {
-        _isLoading = false;
-        _errorMessage = result['message'] ?? 'An unknown error occurred.';
-      });
-      _showSnackBar(_errorMessage, isError: true);
     }
   }
 
diff --git a/lib/screens/marine/manual/data_status_log.dart b/lib/screens/marine/manual/data_status_log.dart
index 28b1156..8fa4afc 100644
--- a/lib/screens/marine/manual/data_status_log.dart
+++ b/lib/screens/marine/manual/data_status_log.dart
@@ -107,14 +107,22 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
     final List<SubmissionLogEntry> tempTarball = [];
 
     for (var log in inSituLogs) {
-      final String dateStr = log['samplingDate'] ?? '';
-      final String timeStr = log['samplingTime'] ?? '';
+      // START FIX: Use backward-compatible keys to read the timestamp
+      final String dateStr = log['sampling_date'] ?? log['man_date'] ?? '';
+      final String timeStr = log['sampling_time'] ?? log['man_time'] ?? '';
+      // END FIX
+
+      // --- START FIX: Prevent fallback to DateTime.now() to make errors visible ---
+      final dt = DateTime.tryParse('$dateStr $timeStr');
+      // --- END FIX ---
 
       tempManual.add(SubmissionLogEntry(
         type: 'Manual Sampling',
         title: log['selectedStation']?['man_station_name'] ?? 'Unknown Station',
         stationCode: log['selectedStation']?['man_station_code'] ?? 'N/A',
-        submissionDateTime: DateTime.tryParse('$dateStr $timeStr') ?? DateTime.now(),
+        // --- START FIX: Use the parsed date or a placeholder for invalid entries ---
+        submissionDateTime: dt ?? DateTime.fromMillisecondsSinceEpoch(0),
+        // --- END FIX ---
         reportId: log['reportId']?.toString(),
         status: log['submissionStatus'] ?? 'L1',
         message: log['submissionMessage'] ?? 'No status message.',
@@ -126,11 +134,14 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
     }
 
     for (var log in tarballLogs) {
+      final dateStr = log['sampling_date'] ?? '';
+      final timeStr = log['sampling_time'] ?? '';
+
       tempTarball.add(SubmissionLogEntry(
         type: 'Tarball Sampling',
         title: log['selectedStation']?['tbl_station_name'] ?? 'Unknown Station',
         stationCode: log['selectedStation']?['tbl_station_code'] ?? 'N/A',
-        submissionDateTime: DateTime.tryParse('${log['sampling_date']} ${log['sampling_time']}') ?? DateTime.now(),
+        submissionDateTime: DateTime.tryParse('$dateStr $timeStr') ?? DateTime.fromMillisecondsSinceEpoch(0),
         reportId: log['reportId']?.toString(),
         status: log['submissionStatus'] ?? 'L1',
         message: log['submissionMessage'] ?? 'No status message.',
@@ -172,6 +183,13 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
         (log.reportId?.toLowerCase() ?? '').contains(query);
   }
 
+  File? _createFileFromPath(String? path) {
+    if (path != null && path.isNotEmpty) {
+      return File(path);
+    }
+    return null;
+  }
+
   Future<void> _resubmitData(SubmissionLogEntry log) async {
     final logKey = log.reportId ?? log.submissionDateTime.toIso8601String();
     if (mounted) {
@@ -187,66 +205,55 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
       Map<String, dynamic> result = {};
 
       if (log.type == 'Manual Sampling') {
-        // START CHANGE: Reconstruct data object and call the new service
+        // --- START FIX: Rely on the now-robust fromJson factory for cleaner reconstruction ---
         final dataToResubmit = InSituSamplingData.fromJson(log.rawData);
-        // Re-attach File objects from paths
-        dataToResubmit.leftLandViewImage = File(log.rawData['man_left_side_land_view'] ?? '');
-        dataToResubmit.rightLandViewImage = File(log.rawData['man_right_side_land_view'] ?? '');
-        dataToResubmit.waterFillingImage = File(log.rawData['man_filling_water_into_sample_bottle'] ?? '');
-        dataToResubmit.seawaterColorImage = File(log.rawData['man_seawater_in_clear_glass_bottle'] ?? '');
-        dataToResubmit.phPaperImage = File(log.rawData['man_examine_preservative_ph_paper'] ?? '');
-        dataToResubmit.optionalImage1 = File(log.rawData['man_optional_photo_01'] ?? '');
-        dataToResubmit.optionalImage2 = File(log.rawData['man_optional_photo_02'] ?? '');
-        dataToResubmit.optionalImage3 = File(log.rawData['man_optional_photo_03'] ?? '');
-        dataToResubmit.optionalImage4 = File(log.rawData['man_optional_photo_04'] ?? '');
+        // --- END FIX ---
 
         result = await _marineInSituService.submitInSituSample(
           data: dataToResubmit,
           appSettings: appSettings,
+          context: context,
+          authProvider: authProvider,
+          logDirectory: log.rawData['logDirectory'] as String?,
         );
-        // END CHANGE
       } else if (log.type == 'Tarball Sampling') {
-        // START CHANGE: Reconstruct data object and call the new service
-        final dataToResubmit = TarballSamplingData(); // Create a fresh instance
+        final dataToResubmit = TarballSamplingData();
         final logData = log.rawData;
 
-        // Manually map fields from the raw log data to the new object
-        dataToResubmit.firstSampler = logData['firstSampler'];
-        dataToResubmit.firstSamplerUserId = logData['firstSamplerUserId'];
+        dataToResubmit.firstSampler = logData['first_sampler_name'];
+        dataToResubmit.firstSamplerUserId = int.tryParse(logData['first_sampler_user_id']?.toString() ?? '');
         dataToResubmit.secondSampler = logData['secondSampler'];
-        dataToResubmit.samplingDate = logData['samplingDate'];
-        dataToResubmit.samplingTime = logData['samplingTime'];
-        dataToResubmit.selectedStateName = logData['selectedStateName'];
-        dataToResubmit.selectedCategoryName = logData['selectedCategoryName'];
+        dataToResubmit.samplingDate = logData['sampling_date'];
+        dataToResubmit.samplingTime = logData['sampling_time'];
+        dataToResubmit.selectedStateName = logData['selectedStation']?['state_name'];
+        dataToResubmit.selectedCategoryName = logData['selectedStation']?['category_name'];
         dataToResubmit.selectedStation = logData['selectedStation'];
-        dataToResubmit.stationLatitude = logData['stationLatitude'];
-        dataToResubmit.stationLongitude = logData['stationLongitude'];
-        dataToResubmit.currentLatitude = logData['currentLatitude'];
-        dataToResubmit.currentLongitude = logData['currentLongitude'];
-        dataToResubmit.distanceDifference = logData['distanceDifference'];
-        dataToResubmit.distanceDifferenceRemarks = logData['distanceDifferenceRemarks'];
-        dataToResubmit.classificationId = logData['classificationId'];
+        dataToResubmit.stationLatitude = logData['selectedStation']?['tbl_latitude']?.toString();
+        dataToResubmit.stationLongitude = logData['selectedStation']?['tbl_longitude']?.toString();
+        dataToResubmit.currentLatitude = logData['current_latitude'];
+        dataToResubmit.currentLongitude = logData['current_longitude'];
+        dataToResubmit.distanceDifference = double.tryParse(logData['distance_difference']?.toString() ?? '');
+        dataToResubmit.distanceDifferenceRemarks = logData['distance_remarks'];
+        dataToResubmit.classificationId = int.tryParse(logData['classification_id']?.toString() ?? '');
         dataToResubmit.selectedClassification = logData['selectedClassification'];
-        dataToResubmit.optionalRemark1 = logData['optionalRemark1'];
-        dataToResubmit.optionalRemark2 = logData['optionalRemark2'];
-        dataToResubmit.optionalRemark3 = logData['optionalRemark3'];
-        dataToResubmit.optionalRemark4 = logData['optionalRemark4'];
-
-        // Re-attach File objects from paths
-        dataToResubmit.leftCoastalViewImage = File(logData['left_side_coastal_view'] ?? '');
-        dataToResubmit.rightCoastalViewImage = File(logData['right_side_coastal_view'] ?? '');
-        dataToResubmit.verticalLinesImage = File(logData['drawing_vertical_lines'] ?? '');
-        dataToResubmit.horizontalLineImage = File(logData['drawing_horizontal_line'] ?? '');
-        dataToResubmit.optionalImage1 = File(logData['optional_photo_01'] ?? '');
-        dataToResubmit.optionalImage2 = File(logData['optional_photo_02'] ?? '');
-        dataToResubmit.optionalImage3 = File(logData['optional_photo_03'] ?? '');
-        dataToResubmit.optionalImage4 = File(logData['optional_photo_04'] ?? '');
+        dataToResubmit.optionalRemark1 = logData['optional_photo_remark_01'];
+        dataToResubmit.optionalRemark2 = logData['optional_photo_remark_02'];
+        dataToResubmit.optionalRemark3 = logData['optional_photo_remark_03'];
+        dataToResubmit.optionalRemark4 = logData['optional_photo_remark_04'];
+        dataToResubmit.leftCoastalViewImage = _createFileFromPath(logData['left_side_coastal_view']);
+        dataToResubmit.rightCoastalViewImage = _createFileFromPath(logData['right_side_coastal_view']);
+        dataToResubmit.verticalLinesImage = _createFileFromPath(logData['drawing_vertical_lines']);
+        dataToResubmit.horizontalLineImage = _createFileFromPath(logData['drawing_horizontal_line']);
+        dataToResubmit.optionalImage1 = _createFileFromPath(logData['optional_photo_01']);
+        dataToResubmit.optionalImage2 = _createFileFromPath(logData['optional_photo_02']);
+        dataToResubmit.optionalImage3 = _createFileFromPath(logData['optional_photo_03']);
+        dataToResubmit.optionalImage4 = _createFileFromPath(logData['optional_photo_04']);
 
         result = await _marineTarballService.submitTarballSample(
           data: dataToResubmit,
           appSettings: appSettings,
+          context: context,
         );
-        // END CHANGE
       }
 
       if (mounted) {
@@ -341,10 +348,31 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
   }
 
   Widget _buildLogListItem(SubmissionLogEntry log) {
-    final isFailed = !log.status.startsWith('S') && !log.status.startsWith('L4');
     final logKey = log.reportId ?? log.submissionDateTime.toIso8601String();
     final isResubmitting = _isResubmitting[logKey] ?? false;
 
+    // --- START: MODIFICATION FOR GRANULAR STATUS ICONS ---
+    // Define the different states based on the detailed status code.
+    final bool isFullSuccess = log.status == 'S4';
+    final bool isPartialSuccess = log.status == 'S3' || log.status == 'L4';
+    final bool canResubmit = !isFullSuccess; // Allow resubmission for partial success or failure.
+
+    // Determine the icon and color based on the state.
+    IconData statusIcon;
+    Color statusColor;
+
+    if (isFullSuccess) {
+      statusIcon = Icons.check_circle_outline;
+      statusColor = Colors.green;
+    } else if (isPartialSuccess) {
+      statusIcon = Icons.warning_amber_rounded;
+      statusColor = Colors.orange;
+    } else {
+      statusIcon = Icons.error_outline;
+      statusColor = Colors.red;
+    }
+    // --- END: MODIFICATION FOR GRANULAR STATUS ICONS ---
+
     final titleWidget = RichText(
       text: TextSpan(
         style: Theme.of(context).textTheme.bodyLarge?.copyWith(fontWeight: FontWeight.w500),
@@ -357,17 +385,18 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
         ],
       ),
     );
-    final subtitle = '${log.serverName} - ${DateFormat('yyyy-MM-dd HH:mm').format(log.submissionDateTime)}';
+
+    final bool isDateValid = !log.submissionDateTime.isAtSameMomentAs(DateTime.fromMillisecondsSinceEpoch(0));
+    final subtitle = isDateValid
+        ? '${log.serverName} - ${DateFormat('yyyy-MM-dd HH:mm').format(log.submissionDateTime)}'
+        : '${log.serverName} - Invalid Date';
 
     return ExpansionTile(
       key: PageStorageKey(logKey),
-      leading: Icon(
-        isFailed ? Icons.error_outline : Icons.check_circle_outline,
-        color: isFailed ? Colors.red : Colors.green,
-      ),
+      leading: Icon(statusIcon, color: statusColor),
       title: titleWidget,
       subtitle: Text(subtitle),
-      trailing: isFailed
+      trailing: canResubmit
           ? (isResubmitting
           ? const SizedBox(height: 24, width: 24, child: CircularProgressIndicator(strokeWidth: 3))
           : IconButton(icon: const Icon(Icons.sync, color: Colors.blue), tooltip: 'Resubmit', onPressed: () => _resubmitData(log)))
@@ -382,9 +411,6 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
               _buildDetailRow('Server:', log.serverName),
               _buildDetailRow('Report ID:', log.reportId ?? 'N/A'),
               _buildDetailRow('Submission Type:', log.type),
-              const Divider(height: 10),
-              _buildGranularStatus('API', log.apiStatusRaw),
-              _buildGranularStatus('FTP', log.ftpStatusRaw),
             ],
           ),
         )
@@ -392,52 +418,6 @@ class _MarineManualDataStatusLogState extends State<MarineManualDataStatusLog> {
     );
   }
 
-  Widget _buildGranularStatus(String type, String? jsonStatus) {
-    if (jsonStatus == null || jsonStatus.isEmpty) {
-      return Container();
-    }
-
-    List<dynamic> statuses;
-    try {
-      statuses = jsonDecode(jsonStatus);
-    } catch (_) {
-      return _buildDetailRow('$type Status:', jsonStatus);
-    }
-
-    if (statuses.isEmpty) {
-      return Container();
-    }
-
-    return Padding(
-      padding: const EdgeInsets.only(top: 8.0),
-      child: Column(
-        crossAxisAlignment: CrossAxisAlignment.start,
-        children: [
-          Text('$type Status:', style: const TextStyle(fontWeight: FontWeight.bold)),
-          ...statuses.map((s) {
-            final serverName = s['server_name'] ?? s['config_name'] ?? 'Server N/A';
-            final status = s['status'] ?? 'N/A';
-            final bool isSuccess = status.toLowerCase().contains('success') || status.toLowerCase().contains('queued') || status.toLowerCase().contains('not_configured') || status.toLowerCase().contains('not_applicable') || status.toLowerCase().contains('not_required');
-            final IconData icon = isSuccess ? Icons.check_circle_outline : (status.toLowerCase().contains('failed') ? Icons.error_outline : Icons.sync);
-            final Color color = isSuccess ? Colors.green : (status.toLowerCase().contains('failed') ? Colors.red : Colors.grey);
-            String detailLabel = (s['type'] != null) ? '(${s['type']})' : '';
-
-            return Padding(
-              padding: const EdgeInsets.symmetric(vertical: 3.0, horizontal: 8.0),
-              child: Row(
-                children: [
-                  Icon(icon, size: 16, color: color),
-                  const SizedBox(width: 5),
-                  Expanded(child: Text('$serverName $detailLabel: $status')),
-                ],
-              ),
-            );
-          }).toList(),
-        ],
-      ),
-    );
-  }
-
   Widget _buildDetailRow(String label, String value) {
     return Padding(
       padding: const EdgeInsets.symmetric(vertical: 4.0),
diff --git a/lib/screens/marine/manual/in_situ_sampling.dart b/lib/screens/marine/manual/in_situ_sampling.dart
index be683a8..06d9dfe 100644
--- a/lib/screens/marine/manual/in_situ_sampling.dart
+++ b/lib/screens/marine/manual/in_situ_sampling.dart
@@ -6,17 +6,12 @@ import 'package:provider/provider.dart';
 import 'package:environment_monitoring_app/auth_provider.dart';
 
 import '../../../models/in_situ_sampling_data.dart';
-// START CHANGE: Import the new, consolidated MarineInSituSamplingService
 import '../../../services/marine_in_situ_sampling_service.dart';
-// END CHANGE
 import 'widgets/in_situ_step_1_sampling_info.dart';
 import 'widgets/in_situ_step_2_site_info.dart';
 import 'widgets/in_situ_step_3_data_capture.dart';
 import 'widgets/in_situ_step_4_summary.dart';
 
-/// The main screen for the In-Situ Sampling feature.
-/// This stateful widget orchestrates the multi-step process using a PageView.
-/// It manages the overall data model and the service layer for the entire workflow.
 class MarineInSituSampling extends StatefulWidget {
   const MarineInSituSampling({super.key});
 
@@ -26,11 +21,7 @@ class MarineInSituSampling extends StatefulWidget {
 
 class _MarineInSituSamplingState extends State<MarineInSituSampling> {
   final PageController _pageController = PageController();
-
   late InSituSamplingData _data;
-
-  // MODIFIED: Declare the service variable but do not instantiate it here.
-  // It will be initialized from the Provider.
   late MarineInSituSamplingService _samplingService;
 
   int _currentPage = 0;
@@ -45,28 +36,24 @@ class _MarineInSituSamplingState extends State<MarineInSituSampling> {
     );
   }
 
-  // ADDED: didChangeDependencies to safely get the service from the Provider.
-  // This is the correct lifecycle method to access inherited widgets like Provider.
   @override
   void didChangeDependencies() {
     super.didChangeDependencies();
-    // Fetch the single, global instance of the service from the Provider tree.
     _samplingService = Provider.of<MarineInSituSamplingService>(context);
   }
 
   @override
   void dispose() {
     _pageController.dispose();
-    // START FIX
-    // REMOVED: _samplingService.dispose();
-    // The service is managed by a higher-level Provider and should not be disposed of
-    // here, as other widgets might still be listening to it. This prevents the
-    // "ValueNotifier was used after being disposed" error.
+    // START FIX: Do not dispose the service here.
+    // The service is managed by the Provider at a higher level in the app. Disposing it
+    // here can cause the "deactivated widget's ancestor" error if other widgets
+    // are still listening to it during screen transitions.
+    // _samplingService.dispose();
     // END FIX
     super.dispose();
   }
 
-  /// Navigates to the next page in the form.
   void _nextPage() {
     if (_currentPage < 3) {
       _pageController.nextPage(
@@ -76,7 +63,6 @@ class _MarineInSituSamplingState extends State<MarineInSituSampling> {
     }
   }
 
-  /// Navigates to the previous page in the form.
   void _previousPage() {
     if (_currentPage > 0) {
       _pageController.previousPage(
@@ -86,25 +72,23 @@ class _MarineInSituSamplingState extends State<MarineInSituSampling> {
     }
   }
 
-  // START CHANGE: The _submitForm method is now greatly simplified.
   Future<void> _submitForm() async {
     setState(() => _isLoading = true);
 
     final authProvider = Provider.of<AuthProvider>(context, listen: false);
     final appSettings = authProvider.appSettings;
 
-    // Delegate the entire submission process to the new dedicated service.
-    // The service handles API calls, zipping, FTP queuing, logging, and alerts.
     final result = await _samplingService.submitInSituSample(
       data: _data,
       appSettings: appSettings,
+      context: context,
+      authProvider: authProvider,
     );
 
     if (!mounted) return;
 
     setState(() => _isLoading = false);
 
-    // Display the final result to the user
     final message = result['message'] ?? 'An unknown error occurred.';
     final color = (result['success'] == true) ? Colors.green : Colors.red;
     ScaffoldMessenger.of(context).showSnackBar(
@@ -113,17 +97,12 @@ class _MarineInSituSamplingState extends State<MarineInSituSampling> {
 
     Navigator.of(context).popUntil((route) => route.isFirst);
   }
-  // END CHANGE
 
 
   @override
   Widget build(BuildContext context) {
-    // START CHANGE: Provide the new MarineInSituSamplingService to all child widgets.
-    // The child widgets (Step 1, 2, 3) can now access all its methods (for location,
-    // image picking, and device connection) via Provider.
     return Provider<MarineInSituSamplingService>.value(
       value: _samplingService,
-      // END CHANGE
       child: Scaffold(
         appBar: AppBar(
           title: Text('In-Situ Sampling (${_currentPage + 1}/4)'),
@@ -143,7 +122,6 @@ class _MarineInSituSamplingState extends State<MarineInSituSampling> {
             });
           },
           children: [
-            // Each step is a separate widget, receiving the data model and navigation callbacks.
             InSituStep1SamplingInfo(data: _data, onNext: _nextPage),
             InSituStep2SiteInfo(data: _data, onNext: _nextPage),
             InSituStep3DataCapture(data: _data, onNext: _nextPage),
diff --git a/lib/screens/marine/manual/tarball_sampling.dart b/lib/screens/marine/manual/tarball_sampling.dart
index 06fbacd..a3f8b53 100644
--- a/lib/screens/marine/manual/tarball_sampling.dart
+++ b/lib/screens/marine/manual/tarball_sampling.dart
@@ -100,12 +100,13 @@ class _MarineTarballSamplingState extends State<MarineTarballSampling> {
     // ADDED: Fetch the global service instance from Provider.
     final tarballService = Provider.of<MarineTarballSamplingService>(context, listen: false);
 
-    // START CHANGE: Call the method on the new dedicated service
+    // START FIX: Pass the required `context` argument to the function call.
     final result = await tarballService.submitTarballSample(
       data: _data,
       appSettings: appSettings,
+      context: context,
     );
-    // END CHANGE
+    // END FIX
 
     if (!mounted) return;
     setState(() => _isLoading = false);
diff --git a/lib/screens/marine/manual/tarball_sampling_step2.dart b/lib/screens/marine/manual/tarball_sampling_step2.dart
index 2d73b3a..4e9de08 100644
--- a/lib/screens/marine/manual/tarball_sampling_step2.dart
+++ b/lib/screens/marine/manual/tarball_sampling_step2.dart
@@ -1,3 +1,5 @@
+// lib/screens/marine/manual/tarball_sampling_step2.dart
+
 import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
@@ -152,7 +154,13 @@ class _TarballSamplingStep2State extends State<TarballSamplingStep2> {
 
     final tempDir = await getTemporaryDirectory();
     final filePath = path.join(tempDir.path, newFileName);
-    final processedFile = await File(filePath).writeAsBytes(img.encodeJpg(originalImage));
+
+    // --- START: MODIFICATION TO FIX RACE CONDITION ---
+    // Changed from asynchronous `writeAsBytes` to synchronous `writeAsBytesSync`.
+    // This guarantees the file is fully written to disk before the function returns,
+    // preventing a 0-byte file from being copied during a fast offline save.
+    final File processedFile = File(filePath)..writeAsBytesSync(img.encodeJpg(originalImage));
+    // --- END: MODIFICATION TO FIX RACE CONDITION ---
 
     setState(() => _isPickingImage = false);
     return processedFile;
diff --git a/lib/screens/marine/manual/tarball_sampling_step3_summary.dart b/lib/screens/marine/manual/tarball_sampling_step3_summary.dart
index 7068934..7a0daa4 100644
--- a/lib/screens/marine/manual/tarball_sampling_step3_summary.dart
+++ b/lib/screens/marine/manual/tarball_sampling_step3_summary.dart
@@ -40,6 +40,7 @@ class _TarballSamplingStep3SummaryState extends State<TarballSamplingStep3Summar
     final result = await tarballService.submitTarballSample(
       data: widget.data,
       appSettings: appSettings,
+      context: context,
     );
 
     if (!mounted) return;
diff --git a/lib/screens/marine/manual/widgets/in_situ_step_3_data_capture.dart b/lib/screens/marine/manual/widgets/in_situ_step_3_data_capture.dart
index d132670..0ef79d0 100644
--- a/lib/screens/marine/manual/widgets/in_situ_step_3_data_capture.dart
+++ b/lib/screens/marine/manual/widgets/in_situ_step_3_data_capture.dart
@@ -34,7 +34,12 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
   bool _isAutoReading = false;
   StreamSubscription? _dataSubscription;
 
+  // --- START FIX: Declare service variable ---
+  late final MarineInSituSamplingService _samplingService;
+  // --- END FIX ---
+
   Map<String, double>? _previousReadingsForComparison;
+  Set<String> _outOfBoundsKeys = {};
 
   /// Maps the app's internal parameter keys to the names used in the
   /// 'param_parameter_list' column from the server.
@@ -70,6 +75,9 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
   @override
   void initState() {
     super.initState();
+    // --- START FIX: Initialize service variable safely ---
+    _samplingService = Provider.of<MarineInSituSamplingService>(context, listen: false);
+    // --- END FIX ---
     _initializeControllers();
     WidgetsBinding.instance.addObserver(this);
   }
@@ -77,6 +85,16 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
   @override
   void dispose() {
     _dataSubscription?.cancel();
+
+    // --- START FIX: Use the pre-fetched service instance ---
+    if (_samplingService.bluetoothConnectionState.value != BluetoothConnectionState.disconnected) {
+      _samplingService.disconnectFromBluetooth();
+    }
+    if (_samplingService.serialConnectionState.value != SerialConnectionState.disconnected) {
+      _samplingService.disconnectFromSerial();
+    }
+    // --- END FIX ---
+
     _disposeControllers();
     WidgetsBinding.instance.removeObserver(this);
     super.dispose();
@@ -201,13 +219,38 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
         }
       }
     } catch (e) {
-      if (mounted) _showSnackBar('Connection failed: $e', isError: true);
+      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 _toggleAutoReading(String activeType) {
     final service = context.read<MarineInSituSamplingService>();
     setState(() {
@@ -222,16 +265,26 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
 
   void _disconnect(String type) {
     final service = context.read<MarineInSituSamplingService>();
-    if (type == 'bluetooth') service.disconnectFromBluetooth(); else service.disconnectFromSerial();
+    if (type == 'bluetooth') {
+      service.disconnectFromBluetooth();
+    } else {
+      service.disconnectFromSerial();
+    }
     _dataSubscription?.cancel();
     _dataSubscription = null;
-    if (mounted) setState(() => _isAutoReading = false);
+    if (mounted) {
+      setState(() => _isAutoReading = false);
+    }
   }
 
   void _disconnectFromAll() {
     final service = context.read<MarineInSituSamplingService>();
-    if (service.bluetoothConnectionState.value != BluetoothConnectionState.disconnected) _disconnect('bluetooth');
-    if (service.serialConnectionState.value != SerialConnectionState.disconnected) _disconnect('serial');
+    if (service.bluetoothConnectionState.value != BluetoothConnectionState.disconnected) {
+      _disconnect('bluetooth');
+    }
+    if (service.serialConnectionState.value != SerialConnectionState.disconnected) {
+      _disconnect('serial');
+    }
   }
 
   void _updateTextFields(Map<String, double> readings) {
@@ -251,38 +304,29 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
   }
 
   void _validateAndProceed() {
-    debugPrint("--- Parameter Validation Triggered ---");
-
     if (_isAutoReading) {
       _showStopReadingDialog();
       return;
     }
+    if (!_formKey.currentState!.validate()) {
+      return;
+    }
     _formKey.currentState!.save();
 
     final currentReadings = _captureReadingsToMap();
-    debugPrint("Current Readings Captured: $currentReadings");
-
     final authProvider = Provider.of<AuthProvider>(context, listen: false);
-    final allLimits = authProvider.parameterLimits ?? [];
-    debugPrint("Total parameter limits loaded from AuthProvider: ${allLimits.length} rules.");
-    if (allLimits.isNotEmpty) {
-      debugPrint("Sample limit rule from AuthProvider: ${allLimits.first}");
-    }
-
-    final marineLimits = allLimits.where((limit) => limit['department_id'] == 4).toList();
-    debugPrint("Found ${marineLimits.length} rules after filtering for Marine department (ID 4).");
-
+    final marineLimits = (authProvider.parameterLimits ?? []).where((limit) => limit['department_id'] == 4).toList();
     final outOfBoundsParams = _validateParameters(currentReadings, marineLimits);
-    debugPrint("Validation check complete. Found ${outOfBoundsParams.length} out-of-bounds parameters.");
+
+    setState(() {
+      _outOfBoundsKeys = outOfBoundsParams.map((p) => _parameters.firstWhere((param) => param['label'] == p['label'])['key'] as String).toSet();
+    });
 
     if (outOfBoundsParams.isNotEmpty) {
-      debugPrint("Action: Displaying parameter limit warning dialog for: $outOfBoundsParams");
       _showParameterLimitDialog(outOfBoundsParams, currentReadings);
     } else {
-      debugPrint("Action: Validation passed or no applicable limits found. Proceeding to the next step.");
       _saveDataAndMoveOn(currentReadings);
     }
-    debugPrint("--- Parameter Validation Finished ---");
   }
 
   Map<String, double> _captureReadingsToMap() {
@@ -352,11 +396,12 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
       return;
     }
 
-    if (_previousReadingsForComparison != null) {
-      setState(() {
+    setState(() {
+      _outOfBoundsKeys.clear();
+      if (_previousReadingsForComparison != null) {
         _previousReadingsForComparison = null;
-      });
-    }
+      }
+    });
 
     widget.onNext();
   }
@@ -431,10 +476,12 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
           if (activeConnection != null)
             _buildConnectionCard(type: activeConnection['type'], connectionState: activeConnection['state'], deviceName: activeConnection['name']),
           const SizedBox(height: 24),
+          // START FIX: Restored ValueListenableBuilder to listen for Sonde ID updates.
           ValueListenableBuilder<String?>(
             valueListenable: service.sondeId,
             builder: (context, sondeId, child) {
               final newSondeId = sondeId ?? '';
+              // Use a post-frame callback to safely update the controller after the build.
               WidgetsBinding.instance.addPostFrameCallback((_) {
                 if (mounted && _sondeIdController.text != newSondeId) {
                   _sondeIdController.text = newSondeId;
@@ -444,12 +491,13 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
               return TextFormField(
                 controller: _sondeIdController,
                 decoration: const InputDecoration(labelText: 'Sonde ID *', hintText: 'Connect device or enter manually'),
-                validator: (v) => v!.isEmpty ? 'Sonde ID is required' : null,
+                validator: (v) => v == null || v.isEmpty ? 'Sonde ID is required' : null,
                 onChanged: (value) => widget.data.sondeId = value,
                 onSaved: (v) => widget.data.sondeId = v,
               );
             },
           ),
+          // END FIX
           const SizedBox(height: 16),
           Row(
             children: [
@@ -470,6 +518,7 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
                 label: param['label'] as String,
                 unit: param['unit'] as String,
                 controller: param['controller'] as TextEditingController,
+                isOutOfBounds: _outOfBoundsKeys.contains(param['key']),
               );
             }).toList(),
           ),
@@ -490,10 +539,10 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
 
     return Card(
       margin: const EdgeInsets.only(top: 24.0),
-      color: Theme.of(context).cardColor, // Adapts to theme's card color
+      color: Theme.of(context).cardColor,
       child: Padding(
         padding: const EdgeInsets.all(16.0),
-        child: DefaultTextStyle( // Ensure text adapts to theme
+        child: DefaultTextStyle(
           style: TextStyle(color: Theme.of(context).textTheme.bodyLarge?.color),
           child: Column(
             crossAxisAlignment: CrossAxisAlignment.start,
@@ -529,6 +578,7 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
                     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: [
@@ -536,15 +586,20 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
                         Padding(
                           padding: const EdgeInsets.all(8.0),
                           child: Text(
-                            previousValue == -999.0 ? '-.--' : previousValue!.toStringAsFixed(2),
+                            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(2),
-                            style: TextStyle(color: isDarkTheme ? Colors.green.shade200 : Colors.green.shade700, fontWeight: FontWeight.bold),
+                            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
+                            ),
                           ),
                         ),
                       ],
@@ -569,7 +624,7 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
           title: const Text('Parameter Limit Warning'),
           content: SingleChildScrollView(
             child: DefaultTextStyle(
-              style: TextStyle(color: Theme.of(context).textTheme.bodyMedium?.color), // Make sure text is visible
+              style: TextStyle(color: Theme.of(context).textTheme.bodyMedium?.color),
               child: Column(
                 mainAxisSize: MainAxisSize.min,
                 crossAxisAlignment: CrossAxisAlignment.start,
@@ -600,12 +655,12 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
                       ...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(1) ?? 'N/A'} - ${p['upper_limit']?.toStringAsFixed(1) ?? 'N/A'}')),
+                          Padding(padding: const EdgeInsets.all(6.0), child: Text('${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(2),
-                              style: const TextStyle(color: Colors.redAccent, fontWeight: FontWeight.bold), // Highlight the out-of-bounds value
+                              p['value'].toStringAsFixed(5),
+                              style: const TextStyle(color: Colors.redAccent, fontWeight: FontWeight.bold),
                             ),
                           ),
                         ],
@@ -641,10 +696,15 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
     );
   }
 
-  Widget _buildParameterListItem({required IconData icon, required String label, required String unit, required TextEditingController controller}) {
+  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(
@@ -654,7 +714,7 @@ class _InSituStep3DataCaptureState extends State<InSituStep3DataCapture> with Wi
           displayValue,
           style: Theme.of(context).textTheme.titleMedium?.copyWith(
               fontWeight: FontWeight.bold,
-              color: isMissing ? Colors.grey : Theme.of(context).colorScheme.primary),
+              color: valueColor),
         ),
       ),
     );
diff --git a/lib/screens/marine/manual/widgets/in_situ_step_4_summary.dart b/lib/screens/marine/manual/widgets/in_situ_step_4_summary.dart
index 671cebd..fbffc91 100644
--- a/lib/screens/marine/manual/widgets/in_situ_step_4_summary.dart
+++ b/lib/screens/marine/manual/widgets/in_situ_step_4_summary.dart
@@ -2,7 +2,9 @@
 
 import 'dart:io';
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
 
+import '../../../../auth_provider.dart';
 import '../../../../models/in_situ_sampling_data.dart';
 
 class InSituStep4Summary extends StatelessWidget {
@@ -17,8 +19,72 @@ class InSituStep4Summary extends StatelessWidget {
     required this.isLoading,
   });
 
+  // --- START: MODIFICATION FOR HIGHLIGHTING ---
+  // Added helper logic to re-validate parameters on the summary screen.
+
+  /// Maps the app's internal parameter keys to the names used in the database.
+  static const 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',
+  };
+
+  /// Re-validates the final parameters against the defined limits.
+  Set<String> _getOutOfBoundsKeys(BuildContext context) {
+    final authProvider = Provider.of<AuthProvider>(context, listen: false);
+    final marineLimits = (authProvider.parameterLimits ?? []).where((limit) => limit['department_id'] == 4).toList();
+    final Set<String> invalidKeys = {};
+
+    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,
+      'tss': data.tss, '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 = marineLimits.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: MODIFICATION FOR HIGHLIGHTING ---
+
   @override
   Widget build(BuildContext context) {
+    // --- START: MODIFICATION FOR HIGHLIGHTING ---
+    // Get the set of out-of-bounds keys before building the list.
+    final outOfBoundsKeys = _getOutOfBoundsKeys(context);
+    // --- END: MODIFICATION FOR HIGHLIGHTING ---
+
     return ListView(
       padding: const EdgeInsets.all(16.0),
       children: [
@@ -91,16 +157,18 @@ class InSituStep4Summary extends StatelessWidget {
             _buildDetailRow("Sonde ID:", data.sondeId),
             _buildDetailRow("Capture Time:", "${data.dataCaptureDate} ${data.dataCaptureTime}"),
             const Divider(height: 20),
-            _buildParameterListItem(context, icon: Icons.air, label: "Oxygen Conc.", unit: "mg/L", value: data.oxygenConcentration?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.percent, label: "Oxygen Sat.", unit: "%", value: data.oxygenSaturation?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.science_outlined, label: "pH", unit: "", value: data.ph?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.waves, label: "Salinity", unit: "ppt", value: data.salinity?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.flash_on, label: "Conductivity", unit: "µS/cm", value: data.electricalConductivity?.toStringAsFixed(0)),
-            _buildParameterListItem(context, icon: Icons.thermostat, label: "Temperature", unit: "°C", value: data.temperature?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.grain, label: "TDS", unit: "mg/L", value: data.tds?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.opacity, label: "Turbidity", unit: "NTU", value: data.turbidity?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.filter_alt_outlined, label: "TSS", unit: "mg/L", value: data.tss?.toStringAsFixed(2)),
-            _buildParameterListItem(context, icon: Icons.battery_charging_full, label: "Battery", unit: "V", value: data.batteryVoltage?.toStringAsFixed(2)),
+            // --- START: MODIFICATION FOR 5 DECIMALS & HIGHLIGHTING ---
+            _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.filter_alt_outlined, label: "TSS", unit: "mg/L", value: data.tss, isOutOfBounds: outOfBoundsKeys.contains('tss')),
+            _buildParameterListItem(context, icon: Icons.battery_charging_full, label: "Battery", unit: "V", value: data.batteryVoltage, isOutOfBounds: outOfBoundsKeys.contains('batteryVoltage')),
+            // --- END: MODIFICATION ---
           ],
         ),
 
@@ -169,11 +237,19 @@ class InSituStep4Summary extends StatelessWidget {
     );
   }
 
-  Widget _buildParameterListItem(BuildContext context, {required IconData icon, required String label, required String unit, required String? value}) {
-    // REPAIRED: Only check if the value is null. It will now display numerical
-    // values like -999.00 instead of converting them to 'N/A'.
-    final bool isMissing = value == null;
-    final String displayValue = isMissing ? 'N/A' : '$value ${unit}'.trim();
+  // --- START: MODIFICATION FOR 5 DECIMALS & HIGHLIGHTING ---
+  Widget _buildParameterListItem(BuildContext context, {required IconData icon, required String label, required String unit, required double? value, bool isOutOfBounds = false}) {
+    final bool isMissing = value == null || value == -999.0;
+    // Format the value to 5 decimal places if it's a valid number.
+    final String displayValue = isMissing ? 'N/A' : '${value.toStringAsFixed(5)} ${unit}'.trim();
+
+    // START CHANGE: Use theme-aware color for normal values
+    // 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
+        : (isMissing ? Colors.grey : defaultTextColor ?? Colors.black);
+    // END CHANGE
 
     return ListTile(
       dense: true,
@@ -183,12 +259,13 @@ class InSituStep4Summary extends StatelessWidget {
       trailing: Text(
         displayValue,
         style: Theme.of(context).textTheme.bodyLarge?.copyWith(
-          color: isMissing ? Colors.grey : null,
-          fontWeight: isMissing ? null : FontWeight.bold,
+          color: valueColor,
+          fontWeight: isOutOfBounds ? FontWeight.bold : null,
         ),
       ),
     );
   }
+  // --- END: MODIFICATION ---
 
   /// A reusable widget to display an attached image or a placeholder.
   Widget _buildImageCard(String title, File? image, {String? remark}) {
diff --git a/lib/screens/river/manual/data_status_log.dart b/lib/screens/river/manual/data_status_log.dart
index 3f4c1b3..8ca64b6 100644
--- a/lib/screens/river/manual/data_status_log.dart
+++ b/lib/screens/river/manual/data_status_log.dart
@@ -80,12 +80,10 @@ class _RiverManualDataStatusLogState extends State<RiverManualDataStatusLog> {
     final riverLogs = await _localStorageService.getAllRiverInSituLogs();
     final List<SubmissionLogEntry> tempLogs = [];
 
-    if (riverLogs != null) {
-      for (var log in riverLogs) {
-        final entry = _createLogEntry(log);
-        if (entry != null) {
-          tempLogs.add(entry);
-        }
+    for (var log in riverLogs) {
+      final entry = _createLogEntry(log);
+      if (entry != null) {
+        tempLogs.add(entry);
       }
     }
 
@@ -99,33 +97,25 @@ class _RiverManualDataStatusLogState extends State<RiverManualDataStatusLog> {
     }
   }
 
+  // --- START: MODIFIED TO FIX NULL SAFETY ERRORS ---
   SubmissionLogEntry? _createLogEntry(Map<String, dynamic> log) {
-    String? type;
-    String? title;
-    String? stationCode;
+    final String type = log['samplingType'] ?? 'In-Situ Sampling';
+    final String title = log['selectedStation']?['sampling_river'] ?? 'Unknown River';
+    final String stationCode = log['selectedStation']?['sampling_station_code'] ?? 'N/A';
     DateTime submissionDateTime = DateTime.now();
-    String? dateStr;
-    String? timeStr;
+    final String? dateStr = log['samplingDate'] ?? log['r_man_date'];
+    final String? timeStr = log['samplingTime'] ?? log['r_man_time'];
 
-    if (log.containsKey('samplingType')) {
-      type = log['samplingType'] ?? 'In-Situ Sampling';
-      title = log['selectedStation']?['sampling_river'] ?? 'Unknown River';
-      stationCode = log['selectedStation']?['sampling_station_code'] ?? 'N/A';
-      dateStr = log['r_man_date'] ?? log['samplingDate'] ?? '';
-      timeStr = log['r_man_time'] ?? log['samplingTime'] ?? '';
-    } else {
-      return null;
-    }
-
-    // FIX: Safely parse date and time by providing default values
     try {
-      final String fullDateString = '$dateStr ${timeStr!.length == 5 ? timeStr + ':00' : timeStr}';
-      submissionDateTime = DateTime.tryParse(fullDateString) ?? DateTime.now();
+      if (dateStr != null && timeStr != null && dateStr.isNotEmpty && timeStr.isNotEmpty) {
+        final String fullDateString = '$dateStr ${timeStr.length == 5 ? "$timeStr:00" : timeStr}';
+        submissionDateTime = DateTime.tryParse(fullDateString) ?? DateTime.now();
+      }
     } catch (_) {
       submissionDateTime = DateTime.now();
     }
+    // --- END: MODIFIED TO FIX NULL SAFETY ERRORS ---
 
-    // FIX: Safely handle apiStatusRaw and ftpStatusRaw to prevent null access
     String? apiStatusRaw;
     if (log['api_status'] != null) {
       apiStatusRaw = log['api_status'] is String ? log['api_status'] : jsonEncode(log['api_status']);
@@ -137,9 +127,9 @@ class _RiverManualDataStatusLogState extends State<RiverManualDataStatusLog> {
     }
 
     return SubmissionLogEntry(
-      type: type!,
-      title: title!,
-      stationCode: stationCode!,
+      type: type,
+      title: title,
+      stationCode: stationCode,
       submissionDateTime: submissionDateTime,
       reportId: log['reportId']?.toString(),
       status: log['submissionStatus'] ?? 'L1',
@@ -178,34 +168,24 @@ class _RiverManualDataStatusLogState extends State<RiverManualDataStatusLog> {
     try {
       final authProvider = Provider.of<AuthProvider>(context, listen: false);
       final appSettings = authProvider.appSettings;
-      final logData = log.rawData;
 
-      final dataToResubmit = RiverInSituSamplingData.fromJson(logData);
-      final Map<String, File?> imageFiles = {};
-      dataToResubmit.toApiImageFiles().keys.forEach((key) {
-        final imagePath = logData[key];
-        if (imagePath is String && imagePath.isNotEmpty) {
-          imageFiles[key] = File(imagePath);
-        }
-      });
-      final result = await _apiService.river.submitInSituSample(
-        formData: dataToResubmit.toApiFormData(),
-        imageFiles: imageFiles,
+      final dataToResubmit = RiverInSituSamplingData.fromJson(log.rawData);
+
+      final result = await _riverInSituService.submitData(
+        data: dataToResubmit,
         appSettings: appSettings,
+        authProvider: authProvider,
+        logDirectory: log.rawData['logDirectory'], // Pass the log directory for updating
       );
 
-      final updatedLogData = log.rawData;
-      updatedLogData['submissionStatus'] = result['status'];
-      updatedLogData['submissionMessage'] = result['message'];
-      updatedLogData['reportId'] = result['reportId']?.toString() ?? updatedLogData['reportId'];
-      updatedLogData['api_status'] = jsonEncode(result['api_status']);
-      updatedLogData['ftp_status'] = jsonEncode(result['ftp_status']);
-
-      await _localStorageService.updateRiverInSituLog(updatedLogData);
-
       if (mounted) {
+        final message = result['message'] ?? 'Resubmission process completed.';
+        final isSuccess = result['success'] as bool? ?? false;
         ScaffoldMessenger.of(context).showSnackBar(
-          const SnackBar(content: Text('Resubmission successful!')),
+          SnackBar(
+            content: Text(message),
+            backgroundColor: isSuccess ? Colors.green : Colors.orange,
+          ),
         );
       }
     } catch (e) {
@@ -371,7 +351,7 @@ class _RiverManualDataStatusLogState extends State<RiverManualDataStatusLog> {
     try {
       statuses = jsonDecode(jsonStatus);
     } catch (_) {
-      return _buildDetailRow('$type Status:', jsonStatus!);
+      return _buildDetailRow('$type Status:', jsonStatus);
     }
 
     if (statuses.isEmpty) {
@@ -385,11 +365,11 @@ class _RiverManualDataStatusLogState extends State<RiverManualDataStatusLog> {
         children: [
           Text('$type Status:', style: const TextStyle(fontWeight: FontWeight.bold)),
           ...statuses.map((s) {
-            final serverName = s['server_name'] ?? 'Server N/A';
-            final status = s['status'] ?? 'N/A';
-            final bool isSuccess = status.toLowerCase().contains('success') || status.toLowerCase().contains('queued') || status.toLowerCase().contains('not_configured') || status.toLowerCase().contains('not_applicable') || status.toLowerCase().contains('not_required');
-            final IconData icon = isSuccess ? Icons.check_circle_outline : (status.toLowerCase().contains('failed') ? Icons.error_outline : Icons.sync);
-            final Color color = isSuccess ? Colors.green : (status.toLowerCase().contains('failed') ? Colors.red : Colors.grey);
+            final serverName = s['server_name'] ?? s['config_name'] ?? 'Server N/A';
+            final status = s['message'] ?? 'N/A';
+            final bool isSuccess = s['success'] as bool? ?? false;
+            final IconData icon = isSuccess ? Icons.check_circle_outline : Icons.error_outline;
+            final Color color = isSuccess ? Colors.green : Colors.red;
             String detailLabel = (s['type'] != null) ? '(${s['type']})' : '';
 
             return Padding(
@@ -421,4 +401,4 @@ class _RiverManualDataStatusLogState extends State<RiverManualDataStatusLog> {
       ),
     );
   }
-}
+}
\ No newline at end of file
diff --git a/lib/screens/river/manual/in_situ_sampling.dart b/lib/screens/river/manual/in_situ_sampling.dart
index 638a742..62c045d 100644
--- a/lib/screens/river/manual/in_situ_sampling.dart
+++ b/lib/screens/river/manual/in_situ_sampling.dart
@@ -43,9 +43,6 @@ class _RiverInSituSamplingScreenState extends State<RiverInSituSamplingScreen> {
   int _currentPage = 0;
   bool _isLoading = false;
 
-  // FIX: Removed the late variable, it will be fetched from context directly.
-  // late RiverInSituSamplingService _samplingService;
-
   @override
   void initState() {
     super.initState();
@@ -53,7 +50,6 @@ class _RiverInSituSamplingScreenState extends State<RiverInSituSamplingScreen> {
       samplingDate: DateFormat('yyyy-MM-dd').format(DateTime.now()),
       samplingTime: DateFormat('HH:mm:ss').format(DateTime.now()),
     );
-    // FIX: Removed the problematic post-frame callback initialization.
   }
 
   @override
@@ -83,30 +79,26 @@ class _RiverInSituSamplingScreenState extends State<RiverInSituSamplingScreen> {
   Future<void> _submitForm() async {
     setState(() => _isLoading = true);
 
-    // FIX: Get the sampling service directly from the context here.
     final samplingService = Provider.of<RiverInSituSamplingService>(context, listen: false);
     final authProvider = Provider.of<AuthProvider>(context, listen: false);
     final appSettings = authProvider.appSettings;
 
-    final result = await samplingService.submitData(_data, appSettings);
-
-    _data.submissionStatus = result['status'];
-    _data.submissionMessage = result['message'];
-    _data.reportId = result['reportId']?.toString();
-
-    final activeApiConfig = await _serverConfigService.getActiveApiConfig();
-    final serverName = activeApiConfig?['config_name'] as String? ?? 'Default';
-    await _localStorageService.saveRiverInSituSamplingData(_data, serverName: serverName);
+    // --- START: MODIFIED SUBMISSION LOGIC ---
+    // The service call is updated to the new signature (no context).
+    // The service now handles all local saving, so the manual save call is removed.
+    final result = await samplingService.submitData(
+      data: _data,
+      appSettings: appSettings,
+      authProvider: authProvider,
+    );
 
     if (!mounted) return;
 
     setState(() => _isLoading = false);
 
-    final message = _data.submissionMessage ?? 'An unknown error occurred.';
+    final message = result['message'] ?? 'An unknown error occurred.';
     final highLevelStatus = result['status'] as String? ?? 'L1';
-
-    final bool isSuccess = highLevelStatus.startsWith('S') || highLevelStatus.startsWith('L4');
-
+    final bool isSuccess = highLevelStatus.startsWith('S') || highLevelStatus.startsWith('L4') || highLevelStatus == 'Queued';
     final color = isSuccess ? Colors.green : Colors.red;
 
     ScaffoldMessenger.of(context).showSnackBar(
@@ -114,13 +106,11 @@ class _RiverInSituSamplingScreenState extends State<RiverInSituSamplingScreen> {
     );
 
     Navigator.of(context).popUntil((route) => route.isFirst);
+    // --- END: MODIFIED SUBMISSION LOGIC ---
   }
 
   @override
   Widget build(BuildContext context) {
-    // FIX: The Provider.value wrapper is removed. The service is already
-    // available in the widget tree from a higher-level provider, and child
-    // widgets can access it using Provider.of or context.read.
     return Scaffold(
       appBar: AppBar(
         title: Text('In-Situ Sampling (${_currentPage + 1}/5)'),
diff --git a/lib/screens/settings.dart b/lib/screens/settings.dart
index 5a68189..3f792fa 100644
--- a/lib/screens/settings.dart
+++ b/lib/screens/settings.dart
@@ -136,6 +136,67 @@ class _SettingsScreenState extends State<SettingsScreen> {
       final apiConfigsWithPrefs = await _preferencesService.getAllApiConfigsWithModulePreferences(moduleKey);
       final ftpConfigsWithPrefs = await _preferencesService.getAllFtpConfigsWithModulePreferences(moduleKey);
 
+      // START MODIFICATION: Apply default settings for submission preferences
+      // This logic checks if the main toggle for a submission type is on but no
+      // specific destination is checked. If so, it applies a default selection.
+      // This ensures a default configuration without overriding saved user choices.
+
+      // Check if any API config is already enabled from preferences.
+      final bool isAnyApiConfigEnabled = apiConfigsWithPrefs.any((c) => c['is_enabled'] == true);
+
+      // If the main API toggle is on but no specific API is selected, apply the default.
+      if (prefs['is_api_enabled'] == true && !isAnyApiConfigEnabled) {
+        final pstwHqApi = apiConfigsWithPrefs.firstWhere((c) => c['config_name'] == 'pstw_hq', orElse: () => {});
+        if (pstwHqApi.isNotEmpty) {
+          pstwHqApi['is_enabled'] = true;
+        }
+      }
+
+      // Check if any FTP config is already enabled from preferences.
+      final bool isAnyFtpConfigEnabled = ftpConfigsWithPrefs.any((c) => c['is_enabled'] == true);
+
+      // If the main FTP toggle is on but no specific FTP is selected, apply the defaults for the module.
+      if (prefs['is_ftp_enabled'] == true && !isAnyFtpConfigEnabled) {
+        switch (moduleKey) {
+          case 'marine_tarball':
+            for (var config in ftpConfigsWithPrefs) {
+              if (config['config_name'] == 'pstw_marine_tarball' || config['config_name'] == 'tes_marine_tarball') {
+                config['is_enabled'] = true;
+              }
+            }
+            break;
+          case 'marine_in_situ':
+            for (var config in ftpConfigsWithPrefs) {
+              if (config['config_name'] == 'pstw_marine_manual' || config['config_name'] == 'tes_marine_manual') {
+                config['is_enabled'] = true;
+              }
+            }
+            break;
+          case 'river_in_situ':
+            for (var config in ftpConfigsWithPrefs) {
+              if (config['config_name'] == 'pstw_river_manual' || config['config_name'] == 'tes_river_manual') {
+                config['is_enabled'] = true;
+              }
+            }
+            break;
+          case 'air_collection':
+            for (var config in ftpConfigsWithPrefs) {
+              if (config['config_name'] == 'pstw_air_collect' || config['config_name'] == 'tes_air_collect') {
+                config['is_enabled'] = true;
+              }
+            }
+            break;
+          case 'air_installation':
+            for (var config in ftpConfigsWithPrefs) {
+              if (config['config_name'] == 'pstw_air_install' || config['config_name'] == 'tes_air_install') {
+                config['is_enabled'] = true;
+              }
+            }
+            break;
+        }
+      }
+      // END MODIFICATION
+
       _moduleSettings[moduleKey] = _ModuleSettings(
         isApiEnabled: prefs['is_api_enabled'],
         isFtpEnabled: prefs['is_ftp_enabled'],
diff --git a/lib/services/air_sampling_service.dart b/lib/services/air_sampling_service.dart
index 452bd1c..538da3c 100644
--- a/lib/services/air_sampling_service.dart
+++ b/lib/services/air_sampling_service.dart
@@ -1,6 +1,7 @@
 // lib/services/air_sampling_service.dart
 
 import 'dart:io';
+import 'dart:async'; // Added for TimeoutException
 import 'package:flutter/foundation.dart';
 import 'package:image_picker/image_picker.dart';
 import 'package:path_provider/path_provider.dart';
@@ -16,15 +17,12 @@ import 'local_storage_service.dart';
 import 'telegram_service.dart';
 import 'server_config_service.dart';
 import 'zipping_service.dart';
-// START CHANGE: Import the new common submission services
 import 'submission_api_service.dart';
 import 'submission_ftp_service.dart';
-// END CHANGE
-
+import 'retry_service.dart'; // Added for queuing failed tasks
 
 /// A dedicated service for handling all business logic for the Air Manual Sampling feature.
 class AirSamplingService {
-  // START CHANGE: Instantiate new services and remove ApiService
   final DatabaseHelper _dbHelper;
   final TelegramService _telegramService;
   final SubmissionApiService _submissionApiService = SubmissionApiService();
@@ -32,9 +30,8 @@ class AirSamplingService {
   final ServerConfigService _serverConfigService = ServerConfigService();
   final ZippingService _zippingService = ZippingService();
   final LocalStorageService _localStorageService = LocalStorageService();
-  // END CHANGE
+  final RetryService _retryService = RetryService(); // Added
 
-  // MODIFIED: Constructor no longer needs ApiService
   AirSamplingService(this._dbHelper, this._telegramService);
 
   // This helper method remains unchanged as it's for local saving logic
@@ -118,149 +115,199 @@ class AirSamplingService {
     return File(filePath)..writeAsBytesSync(img.encodeJpg(originalImage));
   }
 
-  // --- REFACTORED submitInstallation method ---
+  // --- REFACTORED submitInstallation method with granular error handling ---
   Future<Map<String, dynamic>> submitInstallation(AirInstallationData data, List<Map<String, dynamic>>? appSettings) async {
     const String moduleName = 'air_installation';
     final activeConfig = await _serverConfigService.getActiveApiConfig();
     final serverName = activeConfig?['config_name'] as String? ?? 'Default';
 
-    // --- 1. API SUBMISSION (DATA) ---
-    debugPrint("Step 1: Delegating Installation Data submission to SubmissionApiService...");
-    final dataResult = await _submissionApiService.submitPost(
-      moduleName: moduleName,
-      endpoint: 'air/manual/installation',
-      body: data.toJsonForApi(),
-    );
-
-    if (dataResult['success'] != true) {
-      await _logAndSave(data: data, status: 'L1', message: dataResult['message']!, apiResults: [dataResult], ftpStatuses: [], serverName: serverName, type: 'Installation');
-      return {'status': 'L1', 'message': dataResult['message']};
-    }
-
-    final recordId = dataResult['data']?['air_man_id']?.toString();
-    if (recordId == null) {
-      await _logAndSave(data: data, status: 'L1', message: 'API Error: Missing record ID.', apiResults: [dataResult], ftpStatuses: [], serverName: serverName, type: 'Installation');
-      return {'status': 'L1', 'message': 'API Error: Missing record ID.'};
-    }
-    data.airManId = int.tryParse(recordId);
-
-    // --- 2. API SUBMISSION (IMAGES) ---
-    debugPrint("Step 2: Delegating Installation Image submission to SubmissionApiService...");
+    bool anyApiSuccess = false;
+    Map<String, dynamic> apiDataResult = {};
+    Map<String, dynamic> apiImageResult = {};
     final imageFiles = data.getImagesForUpload();
-    final imageResult = await _submissionApiService.submitMultipart(
-      moduleName: moduleName,
-      endpoint: 'air/manual/installation-images',
-      fields: {'air_man_id': recordId},
-      files: imageFiles,
-    );
-    final bool apiImagesSuccess = imageResult['success'] == true;
 
-    // --- 3. FTP SUBMISSION ---
-    debugPrint("Step 3: Delegating Installation FTP submission to SubmissionFtpService...");
-    final stationCode = data.stationID ?? 'UNKNOWN';
-    final samplingDateTime = "${data.installationDate}_${data.installationTime}".replaceAll(':', '-').replaceAll(' ', '_');
-    final baseFileName = "${stationCode}_INSTALLATION_${samplingDateTime}";
+    // Step 1: Attempt API Submission
+    try {
+      apiDataResult = await _submissionApiService.submitPost(
+        moduleName: moduleName,
+        endpoint: 'air/manual/installation',
+        body: data.toJsonForApi(),
+      );
 
-    // Zip and submit data
-    final dataZip = await _zippingService.createDataZip(jsonDataMap: {'db.json': jsonEncode(data.toDbJson())}, baseFileName: baseFileName);
+      if (apiDataResult['success'] == true) {
+        final recordId = apiDataResult['data']?['air_man_id']?.toString();
+        if (recordId != null) {
+          data.airManId = int.tryParse(recordId);
+          apiImageResult = await _submissionApiService.submitMultipart(
+            moduleName: moduleName,
+            endpoint: 'air/manual/installation-images',
+            fields: {'air_man_id': recordId},
+            files: imageFiles,
+          );
+          anyApiSuccess = apiImageResult['success'] == true;
+        } else {
+          anyApiSuccess = false;
+          apiDataResult['message'] = 'API Error: Missing record ID.';
+        }
+      }
+    } on SocketException catch (e) {
+      final errorMessage = "API submission failed with network error: $e";
+      debugPrint(errorMessage);
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': errorMessage};
+      await _retryService.addApiToQueue(endpoint: 'air/manual/installation', method: 'POST', body: data.toJsonForApi());
+    } on TimeoutException catch (e) {
+      final errorMessage = "API submission timed out: $e";
+      debugPrint(errorMessage);
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': errorMessage};
+      await _retryService.addApiToQueue(endpoint: 'air/manual/installation', method: 'POST', body: data.toJsonForApi());
+    }
+
+    // Step 2: Attempt FTP Submission
     Map<String, dynamic> ftpDataResult = {'statuses': []};
-    if (dataZip != null) {
-      ftpDataResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: dataZip, remotePath: '/air/data/${path.basename(dataZip.path)}');
-    }
-
-    // Zip and submit images
-    final imageZip = await _zippingService.createImageZip(imageFiles: imageFiles.values.toList(), baseFileName: baseFileName);
     Map<String, dynamic> ftpImageResult = {'statuses': []};
-    if (imageZip != null) {
-      ftpImageResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: imageZip, remotePath: '/air/images/${path.basename(imageZip.path)}');
+    bool anyFtpSuccess = false;
+    try {
+      final stationCode = data.stationID ?? 'UNKNOWN';
+      final samplingDateTime = "${data.installationDate}_${data.installationTime}".replaceAll(':', '-').replaceAll(' ', '_');
+      final baseFileName = "${stationCode}_INSTALLATION_${samplingDateTime}";
+
+      final dataZip = await _zippingService.createDataZip(jsonDataMap: {'db.json': jsonEncode(data.toDbJson())}, baseFileName: baseFileName);
+      if (dataZip != null) {
+        ftpDataResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: dataZip, remotePath: '/air/data/${path.basename(dataZip.path)}');
+      }
+
+      final imageZip = await _zippingService.createImageZip(imageFiles: imageFiles.values.toList(), baseFileName: baseFileName);
+      if (imageZip != null) {
+        ftpImageResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: imageZip, remotePath: '/air/images/${path.basename(imageZip.path)}');
+      }
+      anyFtpSuccess = !(ftpDataResult['statuses'] as List).any((s) => s['success'] == false) && !(ftpImageResult['statuses'] as List).any((s) => s['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;
     }
 
-    final bool ftpSuccess = (ftpDataResult['success'] == true && ftpImageResult['success'] == true);
-
-    // --- 4. DETERMINE FINAL STATUS, LOG, AND ALERT ---
+    // Step 3: Determine Final Status
     String finalStatus;
     String finalMessage;
-    if (apiImagesSuccess) {
-      finalStatus = ftpSuccess ? 'S4' : 'S2';
-      finalMessage = ftpSuccess ? 'Data and files submitted successfully.' : 'Data submitted to API. FTP upload failed or was queued.';
+    if (anyApiSuccess && anyFtpSuccess) {
+      finalStatus = 'S4';
+      finalMessage = 'Data and files submitted successfully.';
+    } else if (anyApiSuccess && !anyFtpSuccess) {
+      finalStatus = 'S3';
+      finalMessage = 'Data submitted to API, but FTP upload failed and was queued.';
+    } else if (!anyApiSuccess && anyFtpSuccess) {
+      finalStatus = 'L4';
+      finalMessage = 'API submission failed, but files were sent via FTP.';
     } else {
-      finalStatus = ftpSuccess ? 'L2_FTP_ONLY' : 'L2_PENDING_IMAGES';
-      finalMessage = ftpSuccess ? 'API image upload failed, but files were sent via FTP.' : 'Data submitted, but API image and FTP uploads failed.';
+      finalStatus = 'L1';
+      finalMessage = 'Both API and FTP submissions failed and were queued.';
     }
 
-    await _logAndSave(data: data, status: finalStatus, message: finalMessage, apiResults: [dataResult, imageResult], ftpStatuses: [...ftpDataResult['statuses'], ...ftpImageResult['statuses']], serverName: serverName, type: 'Installation');
-    _handleInstallationSuccessAlert(data, appSettings, isDataOnly: !apiImagesSuccess);
+    await _logAndSave(data: data, status: finalStatus, message: finalMessage, apiResults: [apiDataResult, apiImageResult], ftpStatuses: [...ftpDataResult['statuses'], ...ftpImageResult['statuses']], serverName: serverName, type: 'Installation');
+    if (anyApiSuccess || anyFtpSuccess) {
+      _handleInstallationSuccessAlert(data, appSettings, isDataOnly: imageFiles.isEmpty);
+    }
 
     return {'status': finalStatus, 'message': finalMessage};
   }
 
-  // --- REFACTORED submitCollection method ---
+  // --- REFACTORED submitCollection method with granular error handling ---
   Future<Map<String, dynamic>> submitCollection(AirCollectionData data, AirInstallationData installationData, List<Map<String, dynamic>>? appSettings) async {
     const String moduleName = 'air_collection';
     final activeConfig = await _serverConfigService.getActiveApiConfig();
     final serverName = activeConfig?['config_name'] as String? ?? 'Default';
 
-    // --- 1. API SUBMISSION (DATA) ---
-    debugPrint("Step 1: Delegating Collection Data submission to SubmissionApiService...");
-    data.airManId = installationData.airManId; // Ensure collection is linked to installation
-    final dataResult = await _submissionApiService.submitPost(
-      moduleName: moduleName,
-      endpoint: 'air/manual/collection',
-      body: data.toJson(),
-    );
-
-    if (dataResult['success'] != true) {
-      await _logAndSave(data: data, installationData: installationData, status: 'L3', message: dataResult['message']!, apiResults: [dataResult], ftpStatuses: [], serverName: serverName, type: 'Collection');
-      return {'status': 'L3', 'message': dataResult['message']};
-    }
-
-    // --- 2. API SUBMISSION (IMAGES) ---
-    debugPrint("Step 2: Delegating Collection Image submission to SubmissionApiService...");
+    bool anyApiSuccess = false;
+    Map<String, dynamic> apiDataResult = {};
+    Map<String, dynamic> apiImageResult = {};
     final imageFiles = data.getImagesForUpload();
-    final imageResult = await _submissionApiService.submitMultipart(
-      moduleName: moduleName,
-      endpoint: 'air/manual/collection-images',
-      fields: {'air_man_id': data.airManId.toString()},
-      files: imageFiles,
-    );
-    final bool apiImagesSuccess = imageResult['success'] == true;
 
-    // --- 3. FTP SUBMISSION ---
-    debugPrint("Step 3: Delegating Collection FTP submission to SubmissionFtpService...");
-    final stationCode = installationData.stationID ?? 'UNKNOWN';
-    final samplingDateTime = "${data.collectionDate}_${data.collectionTime}".replaceAll(':', '-').replaceAll(' ', '_');
-    final baseFileName = "${stationCode}_COLLECTION_${samplingDateTime}";
+    // Step 1: Attempt API Submission
+    try {
+      data.airManId = installationData.airManId;
+      apiDataResult = await _submissionApiService.submitPost(
+        moduleName: moduleName,
+        endpoint: 'air/manual/collection',
+        body: data.toJson(),
+      );
 
-    // Zip and submit data (includes both installation and collection data)
-    final combinedJson = jsonEncode({"installation": installationData.toDbJson(), "collection": data.toMap()});
-    final dataZip = await _zippingService.createDataZip(jsonDataMap: {'db.json': combinedJson}, baseFileName: baseFileName);
+      if (apiDataResult['success'] == true) {
+        apiImageResult = await _submissionApiService.submitMultipart(
+          moduleName: moduleName,
+          endpoint: 'air/manual/collection-images',
+          fields: {'air_man_id': data.airManId.toString()},
+          files: imageFiles,
+        );
+        anyApiSuccess = apiImageResult['success'] == true;
+      }
+    } on SocketException catch (e) {
+      final errorMessage = "API submission failed with network error: $e";
+      debugPrint(errorMessage);
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': errorMessage};
+      await _retryService.addApiToQueue(endpoint: 'air/manual/collection', method: 'POST', body: data.toJson());
+    } on TimeoutException catch (e) {
+      final errorMessage = "API submission timed out: $e";
+      debugPrint(errorMessage);
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': errorMessage};
+      await _retryService.addApiToQueue(endpoint: 'air/manual/collection', method: 'POST', body: data.toJson());
+    }
+
+    // Step 2: Attempt FTP Submission
     Map<String, dynamic> ftpDataResult = {'statuses': []};
-    if (dataZip != null) {
-      ftpDataResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: dataZip, remotePath: '/air/data/${path.basename(dataZip.path)}');
-    }
-
-    // Zip and submit images
-    final imageZip = await _zippingService.createImageZip(imageFiles: imageFiles.values.toList(), baseFileName: baseFileName);
     Map<String, dynamic> ftpImageResult = {'statuses': []};
-    if (imageZip != null) {
-      ftpImageResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: imageZip, remotePath: '/air/images/${path.basename(imageZip.path)}');
+    bool anyFtpSuccess = false;
+    try {
+      final stationCode = installationData.stationID ?? 'UNKNOWN';
+      final samplingDateTime = "${data.collectionDate}_${data.collectionTime}".replaceAll(':', '-').replaceAll(' ', '_');
+      final baseFileName = "${stationCode}_COLLECTION_${samplingDateTime}";
+
+      final combinedJson = jsonEncode({"installation": installationData.toDbJson(), "collection": data.toMap()});
+      final dataZip = await _zippingService.createDataZip(jsonDataMap: {'db.json': combinedJson}, baseFileName: baseFileName);
+      if (dataZip != null) {
+        ftpDataResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: dataZip, remotePath: '/air/data/${path.basename(dataZip.path)}');
+      }
+
+      final imageZip = await _zippingService.createImageZip(imageFiles: imageFiles.values.toList(), baseFileName: baseFileName);
+      if (imageZip != null) {
+        ftpImageResult = await _submissionFtpService.submit(moduleName: moduleName, fileToUpload: imageZip, remotePath: '/air/images/${path.basename(imageZip.path)}');
+      }
+      anyFtpSuccess = !(ftpDataResult['statuses'] as List).any((s) => s['success'] == false) && !(ftpImageResult['statuses'] as List).any((s) => s['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;
     }
 
-    final bool ftpSuccess = (ftpDataResult['success'] == true && ftpImageResult['success'] == true);
-
-    // --- 4. DETERMINE FINAL STATUS, LOG, AND ALERT ---
+    // Step 3: Determine Final Status
     String finalStatus;
     String finalMessage;
-    if (apiImagesSuccess) {
-      finalStatus = ftpSuccess ? 'S4_API_FTP' : 'S3';
-      finalMessage = ftpSuccess ? 'Data and files submitted successfully.' : 'Data submitted to API. FTP upload failed or was queued.';
+    if (anyApiSuccess && anyFtpSuccess) {
+      finalStatus = 'S4';
+      finalMessage = 'Data and files submitted successfully.';
+    } else if (anyApiSuccess && !anyFtpSuccess) {
+      finalStatus = 'S3';
+      finalMessage = 'Data submitted to API, but FTP upload failed and was queued.';
+    } else if (!anyApiSuccess && anyFtpSuccess) {
+      finalStatus = 'L4';
+      finalMessage = 'API submission failed, but files were sent via FTP.';
     } else {
-      finalStatus = ftpSuccess ? 'L4_FTP_ONLY' : 'L4_PENDING_IMAGES';
-      finalMessage = ftpSuccess ? 'API image upload failed, but files were sent via FTP.' : 'Data submitted, but API image and FTP uploads failed.';
+      finalStatus = 'L1';
+      finalMessage = 'Both API and FTP submissions failed and were queued.';
     }
 
-    await _logAndSave(data: data, installationData: installationData, status: finalStatus, message: finalMessage, apiResults: [dataResult, imageResult], ftpStatuses: [...ftpDataResult['statuses'], ...ftpImageResult['statuses']], serverName: serverName, type: 'Collection');
-    _handleCollectionSuccessAlert(data, installationData, appSettings, isDataOnly: !apiImagesSuccess);
+    await _logAndSave(data: data, installationData: installationData, status: finalStatus, message: finalMessage, apiResults: [apiDataResult, apiImageResult], ftpStatuses: [...ftpDataResult['statuses'], ...ftpImageResult['statuses']], serverName: serverName, type: 'Collection');
+    if(anyApiSuccess || anyFtpSuccess) {
+      _handleCollectionSuccessAlert(data, installationData, appSettings, isDataOnly: imageFiles.isEmpty);
+    }
 
     return {'status': finalStatus, 'message': finalMessage};
   }
@@ -303,7 +350,7 @@ class AirSamplingService {
       'status': status,
       'message': message,
       'report_id': (data.airManId ?? installationData?.airManId)?.toString(),
-      'created_at': DateTime.now(),
+      'created_at': DateTime.now().toIso8601String(),
       'form_data': jsonEncode(formData),
       'image_data': jsonEncode(imagePaths),
       'server_name': serverName,
diff --git a/lib/services/api_service.dart b/lib/services/api_service.dart
index 191289b..080d9ed 100644
--- a/lib/services/api_service.dart
+++ b/lib/services/api_service.dart
@@ -16,41 +16,31 @@ import 'package:environment_monitoring_app/models/tarball_data.dart';
 import 'package:environment_monitoring_app/models/air_collection_data.dart';
 import 'package:environment_monitoring_app/models/air_installation_data.dart';
 import 'package:environment_monitoring_app/models/river_in_situ_sampling_data.dart';
-// START CHANGE: Added import for ServerConfigService to get the base URL
 import 'package:environment_monitoring_app/services/server_config_service.dart';
-// END CHANGE
 
 // =======================================================================
 // Part 1: Unified API Service
 // =======================================================================
 
-/// A unified service that consolidates all API interactions for the application.
-// ... (ApiService class definition remains the same)
-
 class ApiService {
   final BaseApiService _baseService = BaseApiService();
   final DatabaseHelper dbHelper = DatabaseHelper();
-  // START CHANGE: Added ServerConfigService to provide the base URL for API calls
   final ServerConfigService _serverConfigService = ServerConfigService();
-  // END CHANGE
 
   late final MarineApiService marine;
   late final RiverApiService river;
   late final AirApiService air;
 
-  static const String imageBaseUrl = 'https://dev14.pstw.com.my/';
+  static const String imageBaseUrl = 'https://mms-apiv4.pstw.com.my/';
 
   ApiService({required TelegramService telegramService}) {
-    // START CHANGE: Pass the ServerConfigService to the sub-services
     marine = MarineApiService(_baseService, telegramService, _serverConfigService);
     river = RiverApiService(_baseService, telegramService, _serverConfigService);
     air = AirApiService(_baseService, telegramService, _serverConfigService);
-    // END CHANGE
   }
 
-  // --- Core API Methods (Unchanged) ---
+  // --- Core API Methods ---
 
-  // START CHANGE: Update all calls to _baseService to pass the required baseUrl
   Future<Map<String, dynamic>> login(String email, String password) async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.post(baseUrl, 'auth/login', {'email': email, 'password': password});
@@ -92,6 +82,7 @@ class ApiService {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'profile');
   }
+
   Future<Map<String, dynamic>> getAllUsers() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'users');
@@ -101,20 +92,22 @@ class ApiService {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'departments');
   }
+
   Future<Map<String, dynamic>> getAllCompanies() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'companies');
   }
+
   Future<Map<String, dynamic>> getAllPositions() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'positions');
   }
+
   Future<Map<String, dynamic>> getAllStates() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'states');
   }
 
-
   Future<Map<String, dynamic>> sendTelegramAlert({
     required String chatId,
     required String message,
@@ -147,10 +140,8 @@ class ApiService {
         baseUrl: baseUrl,
         endpoint: 'profile/upload-picture',
         fields: {},
-        files: {'profile_picture': imageFile}
-    );
+        files: {'profile_picture': imageFile});
   }
-  // END CHANGE
 
   Future<Map<String, dynamic>> refreshProfile() async {
     debugPrint('ApiService: Refreshing profile data from server...');
@@ -166,47 +157,151 @@ class ApiService {
 
   /// Helper method to make a delta-sync API call.
   Future<Map<String, dynamic>> _fetchDelta(String endpoint, String? lastSyncTimestamp) async {
-    // START CHANGE: Get baseUrl and pass it to the get method
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     String url = endpoint;
     if (lastSyncTimestamp != null) {
-      // Append the 'since' parameter to the URL for delta requests
       url += '?since=$lastSyncTimestamp';
     }
     return _baseService.get(baseUrl, url);
-    // END CHANGE
   }
 
   /// Orchestrates a full DELTA sync from the server to the local database.
   Future<Map<String, dynamic>> syncAllData({String? lastSyncTimestamp}) async {
     debugPrint('ApiService: Starting DELTA data sync. Since: $lastSyncTimestamp');
     try {
-      // Defines all data types to sync, their endpoints, and their DB handlers.
       final syncTasks = {
-        'profile': {'endpoint': 'profile', 'handler': (d, id) async { if (d.isNotEmpty) await dbHelper.saveProfile(d.first); }},
-        'allUsers': {'endpoint': 'users', 'handler': (d, id) async { await dbHelper.upsertUsers(d); await dbHelper.deleteUsers(id); }},
-        // --- ADDED: New sync task for documents ---
-        'documents': {'endpoint': 'documents', 'handler': (d, id) async { await dbHelper.upsertDocuments(d); await dbHelper.deleteDocuments(id); }},
-        // --- END ADDED ---
-        'tarballStations': {'endpoint': 'marine/tarball/stations', 'handler': (d, id) async { await dbHelper.upsertTarballStations(d); await dbHelper.deleteTarballStations(id); }},
-        'manualStations': {'endpoint': 'marine/manual/stations', 'handler': (d, id) async { await dbHelper.upsertManualStations(d); await dbHelper.deleteManualStations(id); }},
-        'tarballClassifications': {'endpoint': 'marine/tarball/classifications', 'handler': (d, id) async { await dbHelper.upsertTarballClassifications(d); await dbHelper.deleteTarballClassifications(id); }},
-        'riverManualStations': {'endpoint': 'river/manual-stations', 'handler': (d, id) async { await dbHelper.upsertRiverManualStations(d); await dbHelper.deleteRiverManualStations(id); }},
-        'riverTriennialStations': {'endpoint': 'river/triennial-stations', 'handler': (d, id) async { await dbHelper.upsertRiverTriennialStations(d); await dbHelper.deleteRiverTriennialStations(id); }},
-        'departments': {'endpoint': 'departments', 'handler': (d, id) async { await dbHelper.upsertDepartments(d); await dbHelper.deleteDepartments(id); }},
-        'companies': {'endpoint': 'companies', 'handler': (d, id) async { await dbHelper.upsertCompanies(d); await dbHelper.deleteCompanies(id); }},
-        'positions': {'endpoint': 'positions', 'handler': (d, id) async { await dbHelper.upsertPositions(d); await dbHelper.deletePositions(id); }},
-        'airManualStations': {'endpoint': 'air/manual-stations', 'handler': (d, id) async { await dbHelper.upsertAirManualStations(d); await dbHelper.deleteAirManualStations(id); }},
-        'airClients': {'endpoint': 'air/clients', 'handler': (d, id) async { await dbHelper.upsertAirClients(d); await dbHelper.deleteAirClients(id); }},
-        'states': {'endpoint': 'states', 'handler': (d, id) async { await dbHelper.upsertStates(d); await dbHelper.deleteStates(id); }},
-        'appSettings': {'endpoint': 'settings', 'handler': (d, id) async { await dbHelper.upsertAppSettings(d); await dbHelper.deleteAppSettings(id); }},
-        'parameterLimits': {'endpoint': 'parameter-limits', 'handler': (d, id) async { await dbHelper.upsertParameterLimits(d); await dbHelper.deleteParameterLimits(id); }},
-        'apiConfigs': {'endpoint': 'api-configs', 'handler': (d, id) async { await dbHelper.upsertApiConfigs(d); await dbHelper.deleteApiConfigs(id); }},
-        'ftpConfigs': {'endpoint': 'ftp-configs', 'handler': (d, id) async { await dbHelper.upsertFtpConfigs(d); await dbHelper.deleteFtpConfigs(id); }},
+        'profile': {
+          'endpoint': 'profile',
+          'handler': (d, id) async {
+            if (d.isNotEmpty) await dbHelper.saveProfile(d.first);
+          }
+        },
+        'allUsers': {
+          'endpoint': 'users',
+          'handler': (d, id) async {
+            // START CHANGE: Use custom upsert method for users
+            await dbHelper.upsertUsers(d);
+            await dbHelper.deleteUsers(id);
+            // END CHANGE
+          }
+        },
+        'documents': {
+          'endpoint': 'documents',
+          'handler': (d, id) async {
+            await dbHelper.upsertDocuments(d);
+            await dbHelper.deleteDocuments(id);
+          }
+        },
+        'tarballStations': {
+          'endpoint': 'marine/tarball/stations',
+          'handler': (d, id) async {
+            await dbHelper.upsertTarballStations(d);
+            await dbHelper.deleteTarballStations(id);
+          }
+        },
+        'manualStations': {
+          'endpoint': 'marine/manual/stations',
+          'handler': (d, id) async {
+            await dbHelper.upsertManualStations(d);
+            await dbHelper.deleteManualStations(id);
+          }
+        },
+        'tarballClassifications': {
+          'endpoint': 'marine/tarball/classifications',
+          'handler': (d, id) async {
+            await dbHelper.upsertTarballClassifications(d);
+            await dbHelper.deleteTarballClassifications(id);
+          }
+        },
+        'riverManualStations': {
+          'endpoint': 'river/manual-stations',
+          'handler': (d, id) async {
+            await dbHelper.upsertRiverManualStations(d);
+            await dbHelper.deleteRiverManualStations(id);
+          }
+        },
+        'riverTriennialStations': {
+          'endpoint': 'river/triennial-stations',
+          'handler': (d, id) async {
+            await dbHelper.upsertRiverTriennialStations(d);
+            await dbHelper.deleteRiverTriennialStations(id);
+          }
+        },
+        'departments': {
+          'endpoint': 'departments',
+          'handler': (d, id) async {
+            await dbHelper.upsertDepartments(d);
+            await dbHelper.deleteDepartments(id);
+          }
+        },
+        'companies': {
+          'endpoint': 'companies',
+          'handler': (d, id) async {
+            await dbHelper.upsertCompanies(d);
+            await dbHelper.deleteCompanies(id);
+          }
+        },
+        'positions': {
+          'endpoint': 'positions',
+          'handler': (d, id) async {
+            await dbHelper.upsertPositions(d);
+            await dbHelper.deletePositions(id);
+          }
+        },
+        'airManualStations': {
+          'endpoint': 'air/manual-stations',
+          'handler': (d, id) async {
+            await dbHelper.upsertAirManualStations(d);
+            await dbHelper.deleteAirManualStations(id);
+          }
+        },
+        'airClients': {
+          'endpoint': 'air/clients',
+          'handler': (d, id) async {
+            await dbHelper.upsertAirClients(d);
+            await dbHelper.deleteAirClients(id);
+          }
+        },
+        'states': {
+          'endpoint': 'states',
+          'handler': (d, id) async {
+            await dbHelper.upsertStates(d);
+            await dbHelper.deleteStates(id);
+          }
+        },
+        'appSettings': {
+          'endpoint': 'settings',
+          'handler': (d, id) async {
+            await dbHelper.upsertAppSettings(d);
+            await dbHelper.deleteAppSettings(id);
+          }
+        },
+        'parameterLimits': {
+          'endpoint': 'parameter-limits',
+          'handler': (d, id) async {
+            await dbHelper.upsertParameterLimits(d);
+            await dbHelper.deleteParameterLimits(id);
+          }
+        },
+        'apiConfigs': {
+          'endpoint': 'api-configs',
+          'handler': (d, id) async {
+            await dbHelper.upsertApiConfigs(d);
+            await dbHelper.deleteApiConfigs(id);
+          }
+        },
+        'ftpConfigs': {
+          'endpoint': 'ftp-configs',
+          'handler': (d, id) async {
+            await dbHelper.upsertFtpConfigs(d);
+            await dbHelper.deleteFtpConfigs(id);
+          }
+        },
       };
 
       // Fetch all deltas in parallel
-      final fetchFutures = syncTasks.map((key, value) => MapEntry(key, _fetchDelta(value['endpoint'] as String, lastSyncTimestamp)));
+      final fetchFutures = syncTasks.map((key, value) =>
+          MapEntry(key, _fetchDelta(value['endpoint'] as String, lastSyncTimestamp)));
       final results = await Future.wait(fetchFutures.values);
       final resultData = Map.fromIterables(fetchFutures.keys, results);
 
@@ -216,7 +311,6 @@ class ApiService {
         final result = entry.value;
 
         if (result['success'] == true && result['data'] != null) {
-          // The profile endpoint has a different structure, handle it separately.
           if (key == 'profile') {
             await (syncTasks[key]!['handler'] as Function)([result['data']], []);
           } else {
@@ -231,7 +325,6 @@ class ApiService {
 
       debugPrint('ApiService: Delta sync complete.');
       return {'success': true, 'message': 'Delta sync successful.'};
-
     } catch (e) {
       debugPrint('ApiService: Delta data sync failed: $e');
       return {'success': false, 'message': 'Data sync failed: $e'};
@@ -246,16 +339,15 @@ class ApiService {
 class AirApiService {
   final BaseApiService _baseService;
   final TelegramService? _telegramService;
-  // START CHANGE: Add ServerConfigService dependency
   final ServerConfigService _serverConfigService;
-  AirApiService(this._baseService, this._telegramService, this._serverConfigService);
-  // END CHANGE
 
-  // START CHANGE: Update all calls to _baseService to pass the required baseUrl
+  AirApiService(this._baseService, this._telegramService, this._serverConfigService);
+
   Future<Map<String, dynamic>> getManualStations() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'air/manual-stations');
   }
+
   Future<Map<String, dynamic>> getClients() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'air/clients');
@@ -296,27 +388,25 @@ class AirApiService {
       files: files,
     );
   }
-// END CHANGE
 }
 
-
 class MarineApiService {
   final BaseApiService _baseService;
   final TelegramService _telegramService;
-  // START CHANGE: Add ServerConfigService dependency
   final ServerConfigService _serverConfigService;
-  MarineApiService(this._baseService, this._telegramService, this._serverConfigService);
-  // END CHANGE
 
-  // START CHANGE: Update all calls to _baseService to pass the required baseUrl
+  MarineApiService(this._baseService, this._telegramService, this._serverConfigService);
+
   Future<Map<String, dynamic>> getTarballStations() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'marine/tarball/stations');
   }
+
   Future<Map<String, dynamic>> getManualStations() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'marine/manual/stations');
   }
+
   Future<Map<String, dynamic>> getTarballClassifications() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'marine/tarball/classifications');
@@ -398,7 +488,8 @@ class MarineApiService {
     };
   }
 
-  Future<void> _handleInSituSuccessAlert(InSituSamplingData data, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly}) async {
+  Future<void> _handleInSituSuccessAlert(InSituSamplingData data,
+      List<Map<String, dynamic>>? appSettings, {required bool isDataOnly}) async {
     try {
       final message = data.generateTelegramAlertMessage(isDataOnly: isDataOnly);
       final bool wasSent = await _telegramService.sendAlertImmediately('marine_in_situ', message, appSettings);
@@ -417,31 +508,40 @@ class MarineApiService {
   }) async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     final dataResult = await _baseService.post(baseUrl, 'marine/tarball/sample', formData);
-    if (dataResult['success'] != true) return {'status': 'L1', 'success': false, 'message': 'Failed to submit data: ${dataResult['message']}'};
+    if (dataResult['success'] != true)
+      return {'status': 'L1', 'success': false, 'message': 'Failed to submit data: ${dataResult['message']}'};
 
     final recordId = dataResult['data']?['autoid'];
     if (recordId == null) return {'status': 'L2', 'success': false, 'message': 'Data submitted, but failed to get a record ID.'};
 
     final filesToUpload = <String, File>{};
-    imageFiles.forEach((key, value) { if (value != null) filesToUpload[key] = value; });
+    imageFiles.forEach((key, value) {
+      if (value != null) filesToUpload[key] = value;
+    });
 
     if (filesToUpload.isEmpty) {
       _handleTarballSuccessAlert(formData, appSettings, isDataOnly: true);
       return {'status': 'L3', 'success': true, 'message': 'Data submitted successfully.', 'reportId': recordId};
     }
 
-    final imageResult = await _baseService.postMultipart(baseUrl: baseUrl, endpoint: 'marine/tarball/images', fields: {'autoid': recordId.toString()}, files: filesToUpload);
+    final imageResult = await _baseService.postMultipart(
+        baseUrl: baseUrl, endpoint: 'marine/tarball/images', fields: {'autoid': recordId.toString()}, files: filesToUpload);
     if (imageResult['success'] != true) {
       _handleTarballSuccessAlert(formData, appSettings, isDataOnly: true);
-      return {'status': 'L2', 'success': false, 'message': 'Data submitted, but image upload failed: ${imageResult['message']}', 'reportId': recordId};
+      return {
+        'status': 'L2',
+        'success': false,
+        'message': 'Data submitted, but image upload failed: ${imageResult['message']}',
+        'reportId': recordId
+      };
     }
 
     _handleTarballSuccessAlert(formData, appSettings, isDataOnly: false);
     return {'status': 'L3', 'success': true, 'message': 'Data and images submitted successfully.', 'reportId': recordId};
   }
-  // END CHANGE
 
-  Future<void> _handleTarballSuccessAlert(Map<String, String> formData, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly}) async {
+  Future<void> _handleTarballSuccessAlert(
+      Map<String, String> formData, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly}) async {
     debugPrint("Triggering Telegram alert logic...");
     try {
       final message = _generateTarballAlertMessage(formData, isDataOnly: isDataOnly);
@@ -489,16 +589,15 @@ class MarineApiService {
 class RiverApiService {
   final BaseApiService _baseService;
   final TelegramService _telegramService;
-  // START CHANGE: Add ServerConfigService dependency
   final ServerConfigService _serverConfigService;
-  RiverApiService(this._baseService, this._telegramService, this._serverConfigService);
-  // END CHANGE
 
-  // START CHANGE: Update all calls to _baseService to pass the required baseUrl
+  RiverApiService(this._baseService, this._telegramService, this._serverConfigService);
+
   Future<Map<String, dynamic>> getManualStations() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'river/manual-stations');
   }
+
   Future<Map<String, dynamic>> getTriennialStations() async {
     final baseUrl = await _serverConfigService.getActiveApiUrl();
     return _baseService.get(baseUrl, 'river/triennial-stations');
@@ -570,9 +669,9 @@ class RiverApiService {
       'reportId': recordId.toString()
     };
   }
-  // END CHANGE
 
-  Future<void> _handleInSituSuccessAlert(Map<String, String> formData, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly}) async {
+  Future<void> _handleInSituSuccessAlert(
+      Map<String, String> formData, List<Map<String, dynamic>>? appSettings, {required bool isDataOnly}) async {
     try {
       final submissionType = isDataOnly ? "(Data Only)" : "(Data & Images)";
       final stationName = formData['r_man_station_name'] ?? 'N/A';
@@ -622,8 +721,7 @@ class RiverApiService {
 class DatabaseHelper {
   static Database? _database;
   static const String _dbName = 'app_data.db';
-  // --- ADDED: Incremented DB version for the new table ---
-  static const int _dbVersion = 20;
+  static const int _dbVersion = 21;
 
   static const String _profileTable = 'user_profile';
   static const String _usersTable = 'all_users';
@@ -645,14 +743,12 @@ class DatabaseHelper {
   static const String _ftpConfigsTable = 'ftp_configurations';
   static const String _retryQueueTable = 'retry_queue';
   static const String _submissionLogTable = 'submission_log';
-  // --- ADDED: New table name for documents ---
   static const String _documentsTable = 'documents';
 
   static const String _modulePreferencesTable = 'module_preferences';
   static const String _moduleApiLinksTable = 'module_api_links';
   static const String _moduleFtpLinksTable = 'module_ftp_links';
 
-
   Future<Database> get database async {
     if (_database != null) return _database!;
     _database = await _initDB();
@@ -666,7 +762,14 @@ class DatabaseHelper {
 
   Future _onCreate(Database db, int version) async {
     await db.execute('CREATE TABLE $_profileTable(user_id INTEGER PRIMARY KEY, profile_json TEXT)');
-    await db.execute('CREATE TABLE $_usersTable(user_id INTEGER PRIMARY KEY, user_json TEXT)');
+    await db.execute('''
+      CREATE TABLE $_usersTable(
+        user_id INTEGER PRIMARY KEY,
+        email TEXT UNIQUE,
+        password_hash TEXT,
+        user_json TEXT
+      )
+    ''');
     await db.execute('CREATE TABLE $_tarballStationsTable(station_id INTEGER PRIMARY KEY, station_json TEXT)');
     await db.execute('CREATE TABLE $_manualStationsTable(station_id INTEGER PRIMARY KEY, station_json TEXT)');
     await db.execute('CREATE TABLE $_riverManualStationsTable(station_id INTEGER PRIMARY KEY, station_json TEXT)');
@@ -693,7 +796,6 @@ class DatabaseHelper {
         status TEXT NOT NULL
       )
     ''');
-    // FIX: Updated CREATE TABLE statement for _submissionLogTable to include api_status and ftp_status
     await db.execute('''
       CREATE TABLE $_submissionLogTable (
         submission_id TEXT PRIMARY KEY,
@@ -710,8 +812,6 @@ class DatabaseHelper {
         ftp_status TEXT
       )
     ''');
-
-    // START CHANGE: Added CREATE TABLE statements for the new tables.
     await db.execute('''
       CREATE TABLE $_modulePreferencesTable (
         module_name TEXT PRIMARY KEY,
@@ -735,9 +835,6 @@ class DatabaseHelper {
         is_enabled INTEGER NOT NULL DEFAULT 1
       )
     ''');
-    // END CHANGE
-
-    // --- ADDED: Create the documents table on initial creation ---
     await db.execute('CREATE TABLE $_documentsTable(id INTEGER PRIMARY KEY, document_json TEXT)');
   }
 
@@ -770,7 +867,6 @@ class DatabaseHelper {
       ''');
     }
     if (oldVersion < 18) {
-      // FIX: Updated UPGRADE TABLE statement for _submissionLogTable to include api_status and ftp_status
       await db.execute('''
         CREATE TABLE IF NOT EXISTS $_submissionLogTable (
           submission_id TEXT PRIMARY KEY,
@@ -786,18 +882,11 @@ class DatabaseHelper {
         )
       ''');
     }
-
-    // Add columns if upgrading from < 18 or if columns were manually dropped (for testing)
-    // NOTE: In a real migration, you'd check if the columns exist first.
     if (oldVersion < 19) {
       try {
         await db.execute("ALTER TABLE $_submissionLogTable ADD COLUMN api_status TEXT");
         await db.execute("ALTER TABLE $_submissionLogTable ADD COLUMN ftp_status TEXT");
-      } catch (_) {
-        // Ignore if columns already exist during a complex migration path
-      }
-
-      // START CHANGE: Add upgrade path for the new preference tables.
+      } catch (_) {}
       await db.execute('''
         CREATE TABLE IF NOT EXISTS $_modulePreferencesTable (
           module_name TEXT PRIMARY KEY,
@@ -821,12 +910,23 @@ class DatabaseHelper {
           is_enabled INTEGER NOT NULL DEFAULT 1
         )
       ''');
-      // END CHANGE
     }
-    // --- ADDED: Upgrade path for the new documents table ---
     if (oldVersion < 20) {
       await db.execute('CREATE TABLE IF NOT EXISTS $_documentsTable(id INTEGER PRIMARY KEY, document_json TEXT)');
     }
+
+    if (oldVersion < 21) {
+      try {
+        await db.execute("ALTER TABLE $_usersTable ADD COLUMN email TEXT");
+      } catch (e) {
+        debugPrint("Upgrade warning: Failed to add email column to users table (may already exist): $e");
+      }
+      try {
+        await db.execute("ALTER TABLE $_usersTable ADD COLUMN password_hash TEXT");
+      } catch (e) {
+        debugPrint("Upgrade warning: Failed to add password_hash column to users table (may already exist): $e");
+      }
+    }
   }
 
   /// Performs an "upsert": inserts new records or replaces existing ones.
@@ -869,43 +969,140 @@ class DatabaseHelper {
 
   Future<void> saveProfile(Map<String, dynamic> profile) async {
     final db = await database;
-    await db.insert(_profileTable, {'user_id': profile['user_id'], 'profile_json': jsonEncode(profile)}, conflictAlgorithm: ConflictAlgorithm.replace);
+    await db.insert(_profileTable, {'user_id': profile['user_id'], 'profile_json': jsonEncode(profile)},
+        conflictAlgorithm: ConflictAlgorithm.replace);
   }
+
   Future<Map<String, dynamic>?> loadProfile() async {
     final db = await database;
     final List<Map<String, dynamic>> maps = await db.query(_profileTable);
-    if(maps.isNotEmpty) return jsonDecode(maps.first['profile_json']);
+    if (maps.isNotEmpty) return jsonDecode(maps.first['profile_json']);
     return null;
   }
 
-  // --- Upsert/Delete/Load methods for all data types ---
+  // --- START: Offline Authentication and User Upsert Methods ---
+
+  /// Retrieves a user's profile JSON from the users table by email.
+  Future<Map<String, dynamic>?> loadProfileByEmail(String email) async {
+    final db = await database;
+    final List<Map<String, dynamic>> maps = await db.query(
+      _usersTable,
+      columns: ['user_json'],
+      where: 'email = ?',
+      whereArgs: [email],
+    );
+    if (maps.isNotEmpty) {
+      try {
+        return jsonDecode(maps.first['user_json']) as Map<String, dynamic>;
+      } catch (e) {
+        debugPrint("Error decoding profile for email $email: $e");
+        return null;
+      }
+    }
+    return null;
+  }
+
+  /// Inserts or replaces a user's profile and credentials.
+  /// This ensures the record exists when caching credentials during login.
+  Future<void> upsertUserWithCredentials({
+    required Map<String, dynamic> profile,
+    required String passwordHash,
+  }) async {
+    final db = await database;
+    await db.insert(
+      _usersTable,
+      {
+        'user_id': profile['user_id'],
+        'email': profile['email'],
+        'password_hash': passwordHash,
+        'user_json': jsonEncode(profile)
+      },
+      conflictAlgorithm: ConflictAlgorithm.replace,
+    );
+    debugPrint("Upserted user credentials for ${profile['email']}");
+  }
+
+  /// Retrieves the stored password hash for a user by email.
+  Future<String?> getUserPasswordHashByEmail(String email) async {
+    final db = await database;
+    final List<Map<String, dynamic>> result = await db.query(
+      _usersTable,
+      columns: ['password_hash'],
+      where: 'email = ?',
+      whereArgs: [email],
+    );
+    if (result.isNotEmpty && result.first['password_hash'] != null) {
+      return result.first['password_hash'] as String;
+    }
+    return null;
+  }
+
+  // --- START: Custom upsert method for user sync to prevent hash overwrite ---
+  /// Upserts user data from sync without overwriting the local password hash.
+  Future<void> upsertUsers(List<Map<String, dynamic>> data) async {
+    if (data.isEmpty) return;
+    final db = await database;
+    for (var item in data) {
+      final updateData = {
+        //'email': item['email'],
+        'user_json': jsonEncode(item),
+      };
+
+      // Try to update existing record first, preserving other columns like password_hash
+      int count = await db.update(
+        _usersTable,
+        updateData,
+        where: 'user_id = ?',
+        whereArgs: [item['user_id']],
+      );
+
+      // If no record was updated (count == 0), insert a new record.
+      if (count == 0) {
+        await db.insert(
+          _usersTable,
+          {
+            'user_id': item['user_id'],
+            'email': item['email'],
+            'user_json': jsonEncode(item),
+            // password_hash will be null for a new user until they log in on this device.
+          },
+          conflictAlgorithm: ConflictAlgorithm.ignore,
+        );
+      }
+    }
+    debugPrint("Upserted ${data.length} user items in custom upsert method.");
+  }
+  // --- END: Custom upsert method ---
 
-  Future<void> upsertUsers(List<Map<String, dynamic>> data) => _upsertData(_usersTable, 'user_id', data, 'user');
   Future<void> deleteUsers(List<dynamic> ids) => _deleteData(_usersTable, 'user_id', ids);
   Future<List<Map<String, dynamic>>?> loadUsers() => _loadData(_usersTable, 'user');
 
-  // --- ADDED: Handlers for the new documents table ---
   Future<void> upsertDocuments(List<Map<String, dynamic>> data) => _upsertData(_documentsTable, 'id', data, 'document');
   Future<void> deleteDocuments(List<dynamic> ids) => _deleteData(_documentsTable, 'id', ids);
   Future<List<Map<String, dynamic>>?> loadDocuments() => _loadData(_documentsTable, 'document');
 
-  Future<void> upsertTarballStations(List<Map<String, dynamic>> data) => _upsertData(_tarballStationsTable, 'station_id', data, 'station');
+  Future<void> upsertTarballStations(List<Map<String, dynamic>> data) =>
+      _upsertData(_tarballStationsTable, 'station_id', data, 'station');
   Future<void> deleteTarballStations(List<dynamic> ids) => _deleteData(_tarballStationsTable, 'station_id', ids);
   Future<List<Map<String, dynamic>>?> loadTarballStations() => _loadData(_tarballStationsTable, 'station');
 
-  Future<void> upsertManualStations(List<Map<String, dynamic>> data) => _upsertData(_manualStationsTable, 'station_id', data, 'station');
+  Future<void> upsertManualStations(List<Map<String, dynamic>> data) =>
+      _upsertData(_manualStationsTable, 'station_id', data, 'station');
   Future<void> deleteManualStations(List<dynamic> ids) => _deleteData(_manualStationsTable, 'station_id', ids);
   Future<List<Map<String, dynamic>>?> loadManualStations() => _loadData(_manualStationsTable, 'station');
 
-  Future<void> upsertRiverManualStations(List<Map<String, dynamic>> data) => _upsertData(_riverManualStationsTable, 'station_id', data, 'station');
+  Future<void> upsertRiverManualStations(List<Map<String, dynamic>> data) =>
+      _upsertData(_riverManualStationsTable, 'station_id', data, 'station');
   Future<void> deleteRiverManualStations(List<dynamic> ids) => _deleteData(_riverManualStationsTable, 'station_id', ids);
   Future<List<Map<String, dynamic>>?> loadRiverManualStations() => _loadData(_riverManualStationsTable, 'station');
 
-  Future<void> upsertRiverTriennialStations(List<Map<String, dynamic>> data) => _upsertData(_riverTriennialStationsTable, 'station_id', data, 'station');
+  Future<void> upsertRiverTriennialStations(List<Map<String, dynamic>> data) =>
+      _upsertData(_riverTriennialStationsTable, 'station_id', data, 'station');
   Future<void> deleteRiverTriennialStations(List<dynamic> ids) => _deleteData(_riverTriennialStationsTable, 'station_id', ids);
   Future<List<Map<String, dynamic>>?> loadRiverTriennialStations() => _loadData(_riverTriennialStationsTable, 'station');
 
-  Future<void> upsertTarballClassifications(List<Map<String, dynamic>> data) => _upsertData(_tarballClassificationsTable, 'classification_id', data, 'classification');
+  Future<void> upsertTarballClassifications(List<Map<String, dynamic>> data) =>
+      _upsertData(_tarballClassificationsTable, 'classification_id', data, 'classification');
   Future<void> deleteTarballClassifications(List<dynamic> ids) => _deleteData(_tarballClassificationsTable, 'classification_id', ids);
   Future<List<Map<String, dynamic>>?> loadTarballClassifications() => _loadData(_tarballClassificationsTable, 'classification');
 
@@ -921,7 +1118,8 @@ class DatabaseHelper {
   Future<void> deletePositions(List<dynamic> ids) => _deleteData(_positionsTable, 'position_id', ids);
   Future<List<Map<String, dynamic>>?> loadPositions() => _loadData(_positionsTable, 'position');
 
-  Future<void> upsertAirManualStations(List<Map<String, dynamic>> data) => _upsertData(_airManualStationsTable, 'station_id', data, 'station');
+  Future<void> upsertAirManualStations(List<Map<String, dynamic>> data) =>
+      _upsertData(_airManualStationsTable, 'station_id', data, 'station');
   Future<void> deleteAirManualStations(List<dynamic> ids) => _deleteData(_airManualStationsTable, 'station_id', ids);
   Future<List<Map<String, dynamic>>?> loadAirManualStations() => _loadData(_airManualStationsTable, 'station');
 
@@ -941,7 +1139,6 @@ class DatabaseHelper {
   Future<void> deleteParameterLimits(List<dynamic> ids) => _deleteData(_parameterLimitsTable, 'param_autoid', ids);
   Future<List<Map<String, dynamic>>?> loadParameterLimits() => _loadData(_parameterLimitsTable, 'limit');
 
-  // --- ADDED: Methods for independent API and FTP configurations ---
   Future<void> upsertApiConfigs(List<Map<String, dynamic>> data) => _upsertData(_apiConfigsTable, 'api_config_id', data, 'config');
   Future<void> deleteApiConfigs(List<dynamic> ids) => _deleteData(_apiConfigsTable, 'api_config_id', ids);
   Future<List<Map<String, dynamic>>?> loadApiConfigs() => _loadData(_apiConfigsTable, 'config');
@@ -950,7 +1147,6 @@ class DatabaseHelper {
   Future<void> deleteFtpConfigs(List<dynamic> ids) => _deleteData(_ftpConfigsTable, 'ftp_config_id', ids);
   Future<List<Map<String, dynamic>>?> loadFtpConfigs() => _loadData(_ftpConfigsTable, 'config');
 
-  // --- ADDED: Methods for the new retry queue ---
   Future<int> queueFailedRequest(Map<String, dynamic> data) async {
     final db = await database;
     return await db.insert(_retryQueueTable, data, conflictAlgorithm: ConflictAlgorithm.replace);
@@ -972,10 +1168,6 @@ class DatabaseHelper {
     await db.delete(_retryQueueTable, where: 'id = ?', whereArgs: [id]);
   }
 
-  // --- ADDED: Methods for the centralized submission log ---
-
-  /// Saves a new submission log entry to the central database table.
-  // FIX: Updated signature to accept api_status and ftp_status
   Future<void> saveSubmissionLog(Map<String, dynamic> data) async {
     final db = await database;
     await db.insert(
@@ -985,7 +1177,6 @@ class DatabaseHelper {
     );
   }
 
-  /// Retrieves all submission log entries, optionally filtered by module.
   Future<List<Map<String, dynamic>>?> loadSubmissionLogs({String? module}) async {
     final db = await database;
     List<Map<String, dynamic>> maps;
@@ -1008,9 +1199,6 @@ class DatabaseHelper {
     return null;
   }
 
-  // START CHANGE: Added helper methods for the new preference tables.
-
-  /// Saves or updates a module's master submission preferences.
   Future<void> saveModulePreference({
     required String moduleName,
     required bool isApiEnabled,
@@ -1028,7 +1216,6 @@ class DatabaseHelper {
     );
   }
 
-  /// Retrieves a module's master submission preferences.
   Future<Map<String, dynamic>?> getModulePreference(String moduleName) async {
     final db = await database;
     final result = await db.query(
@@ -1044,16 +1231,13 @@ class DatabaseHelper {
         'is_ftp_enabled': (row['is_ftp_enabled'] as int) == 1,
       };
     }
-    return null; // Return null if no specific preference is set
+    return null;
   }
 
-  /// Saves the complete set of API links for a specific module, replacing any old ones.
   Future<void> saveApiLinksForModule(String moduleName, List<Map<String, dynamic>> links) async {
     final db = await database;
     await db.transaction((txn) async {
-      // First, delete all existing links for this module
       await txn.delete(_moduleApiLinksTable, where: 'module_name = ?', whereArgs: [moduleName]);
-      // Then, insert all the new links
       for (final link in links) {
         await txn.insert(_moduleApiLinksTable, {
           'module_name': moduleName,
@@ -1064,7 +1248,6 @@ class DatabaseHelper {
     });
   }
 
-  /// Saves the complete set of FTP links for a specific module, replacing any old ones.
   Future<void> saveFtpLinksForModule(String moduleName, List<Map<String, dynamic>> links) async {
     final db = await database;
     await db.transaction((txn) async {
@@ -1079,7 +1262,6 @@ class DatabaseHelper {
     });
   }
 
-  /// Retrieves all API links for a specific module, regardless of enabled status.
   Future<List<Map<String, dynamic>>> getAllApiLinksForModule(String moduleName) async {
     final db = await database;
     final result = await db.query(_moduleApiLinksTable, where: 'module_name = ?', whereArgs: [moduleName]);
@@ -1089,7 +1271,6 @@ class DatabaseHelper {
     }).toList();
   }
 
-  /// Retrieves all FTP links for a specific module, regardless of enabled status.
   Future<List<Map<String, dynamic>>> getAllFtpLinksForModule(String moduleName) async {
     final db = await database;
     final result = await db.query(_moduleFtpLinksTable, where: 'module_name = ?', whereArgs: [moduleName]);
@@ -1098,6 +1279,4 @@ class DatabaseHelper {
       'is_enabled': (row['is_enabled'] as int) == 1,
     }).toList();
   }
-
-// END CHANGE
 }
\ No newline at end of file
diff --git a/lib/services/base_api_service.dart b/lib/services/base_api_service.dart
index 4077e3c..ea8bcec 100644
--- a/lib/services/base_api_service.dart
+++ b/lib/services/base_api_service.dart
@@ -1,7 +1,9 @@
 // lib/services/base_api_service.dart
 
 import 'dart:convert';
-import 'dart:io';
+import 'dart:io'; // Import for SocketException check
+import 'dart:async'; // Import for TimeoutException check
+
 import 'package:flutter/foundation.dart';
 import 'package:http/http.dart' as http;
 import 'package:shared_preferences/shared_preferences.dart';
@@ -34,9 +36,15 @@ class BaseApiService {
       final response = await http.get(url, headers: await _getJsonHeaders())
           .timeout(const Duration(seconds: 60));
       return _handleResponse(response);
+    } on SocketException catch (e) {
+      debugPrint('BaseApiService GET network error: $e');
+      rethrow; // Re-throw network-related exceptions to be caught by higher-level logic (e.g., login screen)
+    } on TimeoutException catch (e) {
+      debugPrint('BaseApiService GET timeout error: $e');
+      rethrow; // Re-throw timeout exceptions
     } catch (e) {
-      debugPrint('GET request to $baseUrl failed: $e');
-      return {'success': false, 'message': 'Network error or timeout: $e'};
+      debugPrint('GET request to $baseUrl failed with general error: $e');
+      return {'success': false, 'message': 'An unexpected error occurred: $e'};
     }
   }
 
@@ -49,10 +57,16 @@ class BaseApiService {
         url,
         headers: await _getJsonHeaders(),
         body: jsonEncode(body),
-      ).timeout(const Duration(seconds: 60));
+      ).timeout(const Duration(seconds: 60)); // Note: login.dart applies its own shorter timeout over this.
       return _handleResponse(response);
+    } on SocketException catch (e) {
+      debugPrint('BaseApiService POST network error: $e');
+      rethrow; // Re-throw network-related exceptions to be caught by higher-level logic (e.g., login screen)
+    } on TimeoutException catch (e) {
+      debugPrint('BaseApiService POST timeout error: $e');
+      rethrow; // Re-throw timeout exceptions
     } catch (e) {
-      debugPrint('POST to $baseUrl failed. Error: $e');
+      debugPrint('POST to $baseUrl failed with general error: $e');
       return {'success': false, 'message': 'API connection failed: $e'};
     }
   }
@@ -92,6 +106,12 @@ class BaseApiService {
       final responseBody = await streamedResponse.stream.bytesToString();
       return _handleResponse(http.Response(responseBody, streamedResponse.statusCode));
 
+    } on SocketException catch (e) {
+      debugPrint('BaseApiService Multipart network error: $e');
+      rethrow; // Re-throw network-related exceptions
+    } on TimeoutException catch (e) {
+      debugPrint('BaseApiService Multipart timeout error: $e');
+      rethrow; // Re-throw timeout exceptions
     } catch (e, s) {
       debugPrint('Multipart upload to $baseUrl failed. Error: $e');
       debugPrint('Stack trace: $s');
@@ -102,14 +122,26 @@ class BaseApiService {
   Map<String, dynamic> _handleResponse(http.Response response) {
     debugPrint('Handling response. Status: ${response.statusCode}, Body: ${response.body}');
     try {
+      // Try to parse the response body as JSON.
       final Map<String, dynamic> responseData = jsonDecode(response.body);
+
       if (response.statusCode >= 200 && response.statusCode < 300) {
-        if (responseData['status'] == 'success' || responseData['success'] == true) {
-          return {'success': true, 'data': responseData['data'], 'message': responseData['message']};
-        } else {
-          return {'success': false, 'message': responseData['message'] ?? 'An unknown API error occurred.'};
+        // Successful API call (2xx status code)
+        // Check application-level success flag if one exists in your API standard.
+        // Assuming your API returns {'status': 'success', 'data': ...} or {'success': true, 'data': ...}
+        if (responseData.containsKey('success') && responseData['success'] == false) {
+          return {'success': false, 'message': responseData['message'] ?? 'API indicated failure.'};
         }
+        // If no explicit failure flag, or if success=true, return success.
+        // Adjust logic based on your API's specific response structure.
+        return {
+          'success': true,
+          'data': responseData['data'], // Assumes data is nested under 'data' key
+          'message': responseData['message'] ?? 'Success'
+        };
       } else {
+        // API returned an error code (4xx, 5xx).
+        // Return the error message provided by the server.
         return {'success': false, 'message': responseData['message'] ?? 'Server error: ${response.statusCode}'};
       }
     } catch (e) {
diff --git a/lib/services/local_storage_service.dart b/lib/services/local_storage_service.dart
index ed68806..89c6e2d 100644
--- a/lib/services/local_storage_service.dart
+++ b/lib/services/local_storage_service.dart
@@ -120,11 +120,6 @@ class LocalStorageService {
         if (serializableData.containsKey(key) && serializableData[key] is File) {
           final newPath = await copyImageToLocal(serializableData[key]);
           serializableData['${key}Path'] = newPath; // Creates 'imageFrontPath', etc.
-          // Note: DO NOT remove the original key here if it holds a File object.
-          // The copy is needed for local storage/DB logging, but the File object must stay
-          // on the key if other process calls `toMap()` again.
-          // However, based on the previous logic, we rely on the caller passing a map
-          // that separates File objects from paths for DB logging.
         }
       }
 
@@ -142,8 +137,6 @@ class LocalStorageService {
         serializableData['collectionData'] = collectionMap;
       }
 
-      // CRITICAL FIX: Ensure the JSON data only contains serializable (non-File) objects
-      // We must strip the File objects before encoding, as they have now been copied.
       final Map<String, dynamic> finalData = Map.from(serializableData);
 
       // Recursive helper to remove File objects before JSON encoding
@@ -154,12 +147,7 @@ class LocalStorageService {
         });
       }
 
-      // Since the caller (_toMapForLocalSave) only passes a map with File objects on the image keys,
-      // and paths on the *Path keys*, simply removing the File keys and encoding is sufficient.
-      finalData.removeWhere((key, value) => value is File);
-      if (finalData.containsKey('collectionData') && finalData['collectionData'] is Map) {
-        cleanMap(finalData['collectionData'] as Map<String, dynamic>);
-      }
+      cleanMap(finalData);
 
 
       final jsonFile = File(p.join(eventDir.path, 'data.json'));
@@ -243,13 +231,25 @@ class LocalStorageService {
       jsonData['serverConfigName'] = serverName;
       jsonData['selectedStation'] = data.selectedStation;
 
+      jsonData['selectedClassification'] = data.selectedClassification;
+      jsonData['secondSampler'] = data.secondSampler;
+
       final imageFiles = data.toImageFiles();
       for (var entry in imageFiles.entries) {
         final File? imageFile = entry.value;
-        if (imageFile != null) {
-          final String originalFileName = p.basename(imageFile.path);
-          final File newFile = await imageFile.copy(p.join(eventDir.path, originalFileName));
-          jsonData[entry.key] = newFile.path;
+        if (imageFile != null && imageFile.path.isNotEmpty) {
+          try {
+            if (p.dirname(imageFile.path) == eventDir.path) {
+              jsonData[entry.key] = imageFile.path;
+            } else {
+              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 image file ${imageFile.path}: $e");
+            jsonData[entry.key] = null;
+          }
         }
       }
 
@@ -319,7 +319,6 @@ class LocalStorageService {
   // Part 4: Marine In-Situ Specific Methods (LOGGING RESTORED)
   // =======================================================================
 
-  // --- MODIFIED: Removed leading underscore to make the method public ---
   Future<Directory?> getInSituBaseDir({required String serverName}) async {
     final mmsv4Dir = await _getPublicMMSV4Directory(serverName: serverName);
     if (mmsv4Dir == null) return null;
@@ -348,17 +347,31 @@ class LocalStorageService {
         await eventDir.create(recursive: true);
       }
 
-      final Map<String, dynamic> jsonData = { ...data.toApiFormData(), 'submissionStatus': data.submissionStatus, 'submissionMessage': data.submissionMessage, 'reportId': data.reportId };
+      // --- START FIX: Explicitly include the final status and message ---
+      // This ensures the status calculated in the service layer is saved correctly.
+      final Map<String, dynamic> jsonData = data.toDbJson();
+      jsonData['submissionStatus'] = data.submissionStatus;
+      jsonData['submissionMessage'] = data.submissionMessage;
+      // --- END FIX ---
+
       jsonData['serverConfigName'] = serverName;
-      jsonData['selectedStation'] = data.selectedStation;
 
       final imageFiles = data.toApiImageFiles();
       for (var entry in imageFiles.entries) {
         final File? imageFile = entry.value;
-        if (imageFile != null) {
-          final String originalFileName = p.basename(imageFile.path);
-          final File newFile = await imageFile.copy(p.join(eventDir.path, originalFileName));
-          jsonData[entry.key] = newFile.path;
+        if (imageFile != null && imageFile.path.isNotEmpty) {
+          try {
+            if (p.dirname(imageFile.path) == eventDir.path) {
+              jsonData[entry.key] = imageFile.path;
+            } else {
+              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 In-Situ image file ${imageFile.path}: $e");
+            jsonData[entry.key] = null;
+          }
         }
       }
 
@@ -462,19 +475,26 @@ class LocalStorageService {
         await eventDir.create(recursive: true);
       }
 
-      final Map<String, dynamic> jsonData = { ...data.toApiFormData(), 'submissionStatus': data.submissionStatus, 'submissionMessage': data.submissionMessage, 'reportId': data.reportId };
+      // --- START: MODIFIED TO USE toMap() FOR COMPLETE DATA SERIALIZATION ---
+      final Map<String, dynamic> jsonData = data.toMap();
       jsonData['serverConfigName'] = serverName;
-      jsonData['selectedStation'] = data.selectedStation;
 
       final imageFiles = data.toApiImageFiles();
       for (var entry in imageFiles.entries) {
         final File? imageFile = entry.value;
         if (imageFile != null) {
           final String originalFileName = p.basename(imageFile.path);
-          final File newFile = await imageFile.copy(p.join(eventDir.path, originalFileName));
-          jsonData[entry.key] = newFile.path;
+          if (p.dirname(imageFile.path) == eventDir.path) {
+            // If file is already in the correct directory, just store the path
+            jsonData[entry.key] = imageFile.path;
+          } else {
+            // Otherwise, copy it to the permanent directory
+            final File newFile = await imageFile.copy(p.join(eventDir.path, originalFileName));
+            jsonData[entry.key] = newFile.path;
+          }
         }
       }
+      // --- END: MODIFIED TO USE toMap() FOR COMPLETE DATA SERIALIZATION ---
 
       final jsonFile = File(p.join(eventDir.path, 'data.json'));
       await jsonFile.writeAsString(jsonEncode(jsonData));
diff --git a/lib/services/marine_in_situ_sampling_service.dart b/lib/services/marine_in_situ_sampling_service.dart
index 3009c87..89c27b4 100644
--- a/lib/services/marine_in_situ_sampling_service.dart
+++ b/lib/services/marine_in_situ_sampling_service.dart
@@ -2,18 +2,21 @@
 
 import 'dart:async';
 import 'dart:io';
+import 'dart:convert';
 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 path;
+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:connectivity_plus/connectivity_plus.dart';
+import 'package:provider/provider.dart';
 
+import '../auth_provider.dart';
 import 'location_service.dart';
 import '../models/in_situ_sampling_data.dart';
 import '../bluetooth/bluetooth_manager.dart';
@@ -25,6 +28,7 @@ import 'api_service.dart';
 import 'submission_api_service.dart';
 import 'submission_ftp_service.dart';
 import 'telegram_service.dart';
+import 'retry_service.dart';
 
 
 /// A dedicated service to handle all business logic for the Marine In-Situ Sampling feature.
@@ -42,10 +46,9 @@ class MarineInSituSamplingService {
   final LocalStorageService _localStorageService = LocalStorageService();
   final ServerConfigService _serverConfigService = ServerConfigService();
   final DatabaseHelper _dbHelper = DatabaseHelper();
-  // MODIFIED: Declare the service, but do not initialize it here.
+  final RetryService _retryService = RetryService();
   final TelegramService _telegramService;
 
-  // ADDED: A constructor to accept the global TelegramService instance.
   MarineInSituSamplingService(this._telegramService);
 
   static const platform = MethodChannel('com.example.environment_monitoring_app/usb');
@@ -83,7 +86,7 @@ class MarineInSituSamplingService {
     final stationCode = data.selectedStation?['man_station_code'] ?? 'NA';
     final fileTimestamp = "${data.samplingDate}-${data.samplingTime}".replaceAll(':', '-');
     final newFileName = "${stationCode}_${fileTimestamp}_${imageInfo.replaceAll(' ', '')}.jpg";
-    final filePath = path.join(tempDir.path, newFileName);
+    final filePath = p.join(tempDir.path, newFileName);
 
     return File(filePath)..writeAsBytesSync(img.encodeJpg(originalImage));
   }
@@ -158,59 +161,206 @@ class MarineInSituSamplingService {
     _serialManager.dispose();
   }
 
-  // --- Data Submission ---
   Future<Map<String, dynamic>> submitInSituSample({
     required InSituSamplingData data,
     required List<Map<String, dynamic>>? appSettings,
+    required AuthProvider authProvider,
+    BuildContext? context,
+    String? logDirectory,
   }) async {
     const String moduleName = 'marine_in_situ';
-    final serverName = (await _serverConfigService.getActiveApiConfig())?['config_name'] as String? ?? 'Default';
 
+    final connectivityResult = await Connectivity().checkConnectivity();
+    bool isOnline = connectivityResult != 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...");
+      final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
+      if (transitionSuccess) {
+        isOfflineSession = false;
+      } else {
+        isOnline = false;
+      }
+    }
+
+    if (isOnline && !isOfflineSession) {
+      debugPrint("Proceeding with direct ONLINE In-Situ submission...");
+      return await _performOnlineSubmission(
+        data: data,
+        appSettings: appSettings,
+        moduleName: moduleName,
+        authProvider: authProvider,
+        logDirectory: logDirectory,
+      );
+    } else {
+      debugPrint("Proceeding with OFFLINE In-Situ queuing mechanism...");
+      return await _performOfflineQueuing(
+        data: data,
+        moduleName: moduleName,
+      );
+    }
+  }
+
+  Future<Map<String, dynamic>> _performOnlineSubmission({
+    required InSituSamplingData 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>();
 
-    // START CHANGE: Implement the correct two-step submission process.
-    // Step 1A: Submit form data as JSON.
-    debugPrint("Step 1A: Submitting In-Situ form data...");
-    final apiDataResult = await _submissionApiService.submitPost(
-      moduleName: moduleName,
-      endpoint: 'marine/manual/sample',
-      body: data.toApiFormData(),
+    bool anyApiSuccess = false;
+    Map<String, dynamic> apiDataResult = {};
+    Map<String, dynamic> apiImageResult = {};
+
+    try {
+      apiDataResult = await _submissionApiService.submitPost(
+        moduleName: moduleName,
+        endpoint: 'marine/manual/sample',
+        body: data.toApiFormData(),
+      );
+
+      if (apiDataResult['success'] == false &&
+          (apiDataResult['message'] as String?)?.contains('Unauthorized') == true) {
+        debugPrint("API submission failed with Unauthorized. Attempting silent relogin...");
+        final bool reloginSuccess = await authProvider.attemptSilentRelogin();
+
+        if (reloginSuccess) {
+          debugPrint("Silent relogin successful. Retrying data submission...");
+          apiDataResult = await _submissionApiService.submitPost(
+            moduleName: moduleName,
+            endpoint: 'marine/manual/sample',
+            body: data.toApiFormData(),
+          );
+        }
+      }
+
+      if (apiDataResult['success'] == true) {
+        anyApiSuccess = true;
+        data.reportId = apiDataResult['data']?['man_id']?.toString();
+
+        if (data.reportId != null) {
+          if (finalImageFiles.isNotEmpty) {
+            apiImageResult = await _submissionApiService.submitMultipart(
+              moduleName: moduleName,
+              endpoint: 'marine/manual/images',
+              fields: {'man_id': data.reportId!},
+              files: finalImageFiles,
+            );
+            if (apiImageResult['success'] != true) {
+              anyApiSuccess = false;
+            }
+          }
+        } else {
+          anyApiSuccess = false;
+          apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
+        }
+      }
+    } on SocketException catch (e) {
+      final errorMessage = "API submission failed with network error: $e";
+      debugPrint(errorMessage);
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': errorMessage};
+      await _retryService.addApiToQueue(endpoint: 'marine/manual/sample', method: 'POST', body: data.toApiFormData());
+      if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        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());
+    }
+
+    Map<String, dynamic> ftpResults = {'statuses': []};
+    bool anyFtpSuccess = false;
+    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");
+      anyFtpSuccess = false;
+    }
+
+    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.';
+      finalStatus = 'S3';
+    } else if (!anyApiSuccess && anyFtpSuccess) {
+      finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
+      finalStatus = 'L4';
+    } else {
+      finalMessage = 'All submission attempts failed and have been queued for retry.';
+      finalStatus = 'L1';
+    }
+
+    await _logAndSave(
+      data: data,
+      status: finalStatus,
+      message: finalMessage,
+      apiResults: [apiDataResult, apiImageResult],
+      ftpStatuses: ftpResults['statuses'],
+      serverName: serverName,
+      finalImageFiles: finalImageFiles,
+      logDirectory: logDirectory,
     );
 
-    // If the initial data submission fails, log and exit early.
-    if (apiDataResult['success'] != true) {
-      data.submissionStatus = 'L1';
-      data.submissionMessage = apiDataResult['message'] ?? 'Failed to submit form data.';
-      await _logAndSave(data: data, apiResults: [apiDataResult], ftpStatuses: [], serverName: serverName, finalImageFiles: finalImageFiles);
-      return {'success': false, 'message': data.submissionMessage};
+    if (overallSuccess) {
+      _handleInSituSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty);
     }
 
-    final reportId = apiDataResult['data']?['man_id']?.toString();
-    if (reportId == null) {
-      data.submissionStatus = 'L1';
-      data.submissionMessage = 'API Error: Missing man_id in response.';
-      await _logAndSave(data: data, apiResults: [apiDataResult], ftpStatuses: [], serverName: serverName, finalImageFiles: finalImageFiles);
-      return {'success': false, 'message': data.submissionMessage};
-    }
-    data.reportId = reportId;
+    return {'success': overallSuccess, 'message': finalMessage, 'reportId': data.reportId};
+  }
 
-    // Step 1B: Submit images as multipart/form-data.
-    debugPrint("Step 1B: Submitting In-Situ images...");
-    Map<String, dynamic> apiImageResult = {'success': true, 'message': 'No images to upload.'};
-    if (finalImageFiles.isNotEmpty) {
-      apiImageResult = await _submissionApiService.submitMultipart(
-        moduleName: moduleName,
-        endpoint: 'marine/manual/images', // Assumed endpoint for uploadManualImages
-        fields: {'man_id': reportId},
-        files: finalImageFiles,
-      );
-    }
-    final bool apiSuccess = apiImageResult['success'] == true;
-    // END CHANGE
+  Future<Map<String, dynamic>> _performOfflineQueuing({
+    required InSituSamplingData data,
+    required String moduleName,
+  }) async {
+    final serverConfig = await _serverConfigService.getActiveApiConfig();
+    final serverName = serverConfig?['config_name'] as String? ?? 'Default';
 
-    // Step 2: FTP Submission
+    // Set initial status before first save
+    data.submissionStatus = 'L1';
+    data.submissionMessage = 'Submission queued due to being offline.';
+
+    final String? localLogPath = await _localStorageService.saveInSituSamplingData(data, serverName: serverName);
+
+    if (localLogPath == null) {
+      const message = "Failed to save submission to local device storage.";
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {});
+      return {'success': false, 'message': message};
+    }
+
+    await _retryService.queueTask(
+      type: 'insitu_submission',
+      payload: {
+        'module': moduleName,
+        'localLogPath': localLogPath,
+        'serverConfig': serverConfig,
+      },
+    );
+
+    // No need to save again, initial save already has the L1 status.
+    const successMessage = "No internet connection. Submission has been saved and queued for upload.";
+    return {'success': true, 'message': successMessage};
+  }
+
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(InSituSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
     final stationCode = data.selectedStation?['man_station_code'] ?? 'NA';
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
     final baseFileName = '${stationCode}_$fileTimestamp';
@@ -220,77 +370,86 @@ class MarineInSituSamplingService {
       module: 'marine',
       subModule: 'marine_in_situ_sampling',
     );
-
-    final Directory? localSubmissionDir = logDirectory != null ? Directory(path.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
     if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
       await localSubmissionDir.create(recursive: true);
     }
 
     final dataZip = await _zippingService.createDataZip(
-        jsonDataMap: {'db.json': jsonEncode(data.toDbJson())},
-        baseFileName: baseFileName,
-        destinationDir: localSubmissionDir);
+      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: '/${path.basename(dataZip.path)}');
+        moduleName: moduleName,
+        fileToUpload: dataZip,
+        remotePath: '/${p.basename(dataZip.path)}',
+      );
     }
 
     final imageZip = await _zippingService.createImageZip(
-        imageFiles: finalImageFiles.values.toList(),
-        baseFileName: baseFileName,
-        destinationDir: localSubmissionDir);
+      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: '/${path.basename(imageZip.path)}');
-    }
-    final bool ftpSuccess = (ftpDataResult['success'] == true && ftpImageResult['success'] == true);
-
-    // Step 3: Finalize and Log
-    String finalStatus;
-    String finalMessage;
-    if (apiSuccess) {
-      finalStatus = ftpSuccess ? 'S4' : 'S3';
-      finalMessage = ftpSuccess ? 'Data submitted successfully.' : 'Data sent to API. FTP upload failed/queued.';
-    } else {
-      finalStatus = ftpSuccess ? 'L4' : 'L1';
-      finalMessage = ftpSuccess ? 'API failed, but files sent to FTP.' : 'All submission attempts failed.';
+        moduleName: moduleName,
+        fileToUpload: imageZip,
+        remotePath: '/${p.basename(imageZip.path)}',
+      );
     }
 
-    data.submissionStatus = finalStatus;
-    data.submissionMessage = finalMessage;
-
-    await _logAndSave(
-      data: data,
-      apiResults: [apiDataResult, apiImageResult], // Log both API steps
-      ftpStatuses: [...ftpDataResult['statuses'], ...ftpImageResult['statuses']],
-      serverName: serverName,
-      finalImageFiles: finalImageFiles,
-    );
-
-    if (apiSuccess || ftpSuccess) {
-      _handleInSituSuccessAlert(data, appSettings, isDataOnly: !apiSuccess);
-    }
-
-    return {'success': apiSuccess || ftpSuccess, 'message': finalMessage};
+    return {
+      'statuses': <Map<String, dynamic>>[
+        ...(ftpDataResult['statuses'] as List),
+        ...(ftpImageResult['statuses'] as List),
+      ],
+    };
   }
 
-  // Helper function to centralize logging and local saving.
   Future<void> _logAndSave({
     required InSituSamplingData 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,
+    String? logDirectory,
   }) async {
+    data.submissionStatus = status;
+    data.submissionMessage = message;
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
 
-    await _localStorageService.saveInSituSamplingData(data, serverName: serverName);
+    if (logDirectory != null) {
+      final Map<String, dynamic> updatedLogData = data.toDbJson();
+
+      // --- START FIX: Explicitly add final status and message to the update map ---
+      updatedLogData['submissionStatus'] = status;
+      updatedLogData['submissionMessage'] = message;
+      // --- END FIX ---
+
+      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;
+        }
+      });
+
+      await _localStorageService.updateInSituLog(updatedLogData);
+    } else {
+      await _localStorageService.saveInSituSamplingData(data, serverName: serverName);
+    }
+
 
     final logData = {
       'submission_id': data.reportId ?? fileTimestamp,
diff --git a/lib/services/marine_tarball_sampling_service.dart b/lib/services/marine_tarball_sampling_service.dart
index 095a78e..82d682f 100644
--- a/lib/services/marine_tarball_sampling_service.dart
+++ b/lib/services/marine_tarball_sampling_service.dart
@@ -2,8 +2,12 @@
 
 import 'dart:io';
 import 'dart:convert';
+import 'dart:async'; // Added for TimeoutException
 import 'package:flutter/foundation.dart';
 import 'package:path/path.dart' as p;
+import 'package:connectivity_plus/connectivity_plus.dart';
+import 'package:provider/provider.dart';
+import 'package:flutter/material.dart';
 
 import 'package:environment_monitoring_app/models/tarball_data.dart';
 import 'package:environment_monitoring_app/services/local_storage_service.dart';
@@ -13,6 +17,8 @@ import 'package:environment_monitoring_app/services/api_service.dart';
 import 'package:environment_monitoring_app/services/submission_api_service.dart';
 import 'package:environment_monitoring_app/services/submission_ftp_service.dart';
 import 'package:environment_monitoring_app/services/telegram_service.dart';
+import 'package:environment_monitoring_app/services/retry_service.dart';
+import 'package:environment_monitoring_app/auth_provider.dart';
 
 /// A dedicated service to handle all business logic for the Marine Tarball Sampling feature.
 class MarineTarballSamplingService {
@@ -22,57 +28,210 @@ class MarineTarballSamplingService {
   final LocalStorageService _localStorageService = LocalStorageService();
   final ServerConfigService _serverConfigService = ServerConfigService();
   final DatabaseHelper _dbHelper = DatabaseHelper();
-  // MODIFIED: Declare the service, but do not initialize it here.
+  final RetryService _retryService = RetryService();
   final TelegramService _telegramService;
 
-  // ADDED: A constructor to accept the global TelegramService instance.
   MarineTarballSamplingService(this._telegramService);
 
   Future<Map<String, dynamic>> submitTarballSample({
     required TarballSamplingData data,
     required List<Map<String, dynamic>>? appSettings,
+    required BuildContext context,
   }) async {
     const String moduleName = 'marine_tarball';
+    final authProvider = Provider.of<AuthProvider>(context, listen: false);
+
+    final connectivityResult = await Connectivity().checkConnectivity();
+    bool isOnline = connectivityResult != ConnectivityResult.none;
+    bool isOfflineSession = authProvider.isLoggedIn && (authProvider.profileData?['token']?.startsWith("offline-session-") ?? false);
+
+    if (isOnline && isOfflineSession) {
+      debugPrint("Submission initiated online during an offline session. Attempting auto-relogin...");
+      final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
+      if (transitionSuccess) {
+        isOfflineSession = false;
+      } else {
+        isOnline = false;
+      }
+    }
+
+    if (isOnline && !isOfflineSession) {
+      debugPrint("Proceeding with direct ONLINE submission...");
+      return await _performOnlineSubmission(
+        data: data,
+        appSettings: appSettings,
+        moduleName: moduleName,
+        authProvider: authProvider,
+      );
+    } else {
+      debugPrint("Proceeding with OFFLINE queuing mechanism...");
+      return await _performOfflineQueuing(
+        data: data,
+        moduleName: moduleName,
+      );
+    }
+  }
+
+  Future<Map<String, dynamic>> _performOnlineSubmission({
+    required TarballSamplingData data,
+    required List<Map<String, dynamic>>? appSettings,
+    required String moduleName,
+    required AuthProvider authProvider,
+  }) async {
     final serverName = (await _serverConfigService.getActiveApiConfig())?['config_name'] as String? ?? 'Default';
+    final imageFiles = data.toImageFiles()..removeWhere((key, value) => value == null);
+    final finalImageFiles = imageFiles.cast<String, File>();
 
-    final imageFilesWithNulls = data.toImageFiles();
-    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 = {};
 
-    // START CHANGE: Revert to the correct two-step API submission process
-    // --- Step 1A: API Data Submission ---
-    debugPrint("Step 1A: Submitting Tarball form data...");
-    final apiDataResult = await _submissionApiService.submitPost(
-      moduleName: moduleName,
-      endpoint: 'marine/tarball/sample',
-      body: data.toFormData(),
-    );
+    // --- START: MODIFICATION FOR GRANULAR ERROR HANDLING ---
+    // Step 1: Attempt API Submission in its own try-catch block.
+    try {
+      apiDataResult = await _submissionApiService.submitPost(
+        moduleName: moduleName,
+        endpoint: 'marine/tarball/sample',
+        body: data.toFormData(),
+      );
 
-    if (apiDataResult['success'] != true) {
-      // If the initial data submission fails, log and exit early.
-      await _logAndSave(data: data, status: 'L1', message: apiDataResult['message']!, apiResults: [apiDataResult], ftpStatuses: [], serverName: serverName, finalImageFiles: finalImageFiles);
-      return {'success': false, 'message': apiDataResult['message']};
+      if (apiDataResult['success'] == false &&
+          (apiDataResult['message'] as String?)?.contains('Unauthorized') == true) {
+        debugPrint("API submission failed with Unauthorized. Attempting silent relogin...");
+        final bool reloginSuccess = await authProvider.attemptSilentRelogin();
+
+        if (reloginSuccess) {
+          debugPrint("Silent relogin successful. Retrying data submission...");
+          apiDataResult = await _submissionApiService.submitPost(
+            moduleName: moduleName,
+            endpoint: 'marine/tarball/sample',
+            body: data.toFormData(),
+          );
+        }
+      }
+
+      if (apiDataResult['success'] == true) {
+        anyApiSuccess = true;
+        data.reportId = apiDataResult['data']?['autoid']?.toString();
+
+        if (data.reportId != null) {
+          apiImageResult = await _submissionApiService.submitMultipart(
+            moduleName: moduleName,
+            endpoint: 'marine/tarball/images',
+            fields: {'autoid': data.reportId!},
+            files: finalImageFiles,
+          );
+          if (apiImageResult['success'] != true) {
+            anyApiSuccess = false; // Downgrade success if images fail
+          }
+        } else {
+          anyApiSuccess = false;
+          apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
+        }
+      }
+    } on SocketException catch (e) {
+      final errorMessage = "API submission failed with network error: $e";
+      debugPrint(errorMessage);
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': errorMessage};
+      // Manually queue the failed API tasks since the service might not have been able to
+      await _retryService.addApiToQueue(endpoint: 'marine/tarball/sample', method: 'POST', body: data.toFormData());
+      if(finalImageFiles.isNotEmpty && data.reportId != null) {
+        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());
     }
 
-    final recordId = apiDataResult['data']?['autoid']?.toString();
-    if (recordId == null) {
-      await _logAndSave(data: data, status: 'L1', message: 'API Error: Missing record ID.', apiResults: [apiDataResult], ftpStatuses: [], serverName: serverName, finalImageFiles: finalImageFiles);
-      return {'success': false, 'message': 'API Error: Missing record ID.'};
+    // Step 2: Attempt FTP Submission in its own try-catch block.
+    // This code will now run even if the API submission above failed.
+    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;
+      // Note: The underlying SubmissionFtpService already queues failed uploads,
+      // so we just need to catch the error to prevent a crash.
+    } on TimeoutException catch (e) {
+      debugPrint("FTP submission timed out: $e");
+      anyFtpSuccess = false;
     }
-    data.reportId = recordId;
+    // --- END: MODIFICATION FOR GRANULAR ERROR HANDLING ---
 
-    // --- Step 1B: API Image Submission ---
-    debugPrint("Step 1B: Submitting Tarball images...");
-    final apiImageResult = await _submissionApiService.submitMultipart(
-      moduleName: moduleName,
-      endpoint: 'marine/tarball/images',
-      fields: {'autoid': recordId},
-      files: finalImageFiles,
+    // Step 3: Determine final status based on the outcomes of the independent steps.
+    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.';
+      finalStatus = 'S3';
+    } else if (!anyApiSuccess && anyFtpSuccess) {
+      finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
+      finalStatus = 'L4';
+    } else {
+      finalMessage = 'All submission attempts failed and have been queued for retry.';
+      finalStatus = 'L1';
+    }
+
+    await _logAndSave(
+      data: data,
+      status: finalStatus,
+      message: finalMessage,
+      apiResults: [apiDataResult, apiImageResult],
+      ftpStatuses: ftpResults['statuses'],
+      serverName: serverName,
+      finalImageFiles: finalImageFiles,
     );
-    final bool apiSuccess = apiImageResult['success'] == true;
-    // END CHANGE
 
-    // --- Step 2: FTP Submission ---
+    if (overallSuccess) {
+      _handleTarballSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty);
+    }
+
+    return {'success': overallSuccess, 'message': finalMessage, 'reportId': data.reportId};
+  }
+
+  Future<Map<String, dynamic>> _performOfflineQueuing({
+    required TarballSamplingData data,
+    required String moduleName,
+  }) async {
+    final serverConfig = await _serverConfigService.getActiveApiConfig();
+    final serverName = serverConfig?['config_name'] as String? ?? 'Default';
+
+    final String? localLogPath = await _localStorageService.saveTarballSamplingData(data, serverName: serverName);
+
+    if (localLogPath == null) {
+      const message = "Failed to save submission to local device storage.";
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {});
+      return {'success': false, 'message': message};
+    }
+
+    await _retryService.queueTask(
+      type: 'tarball_submission',
+      payload: {
+        'module': moduleName,
+        'localLogPath': localLogPath,
+        'serverConfig': serverConfig,
+      },
+    );
+
+    const successMessage = "No internet connection. Submission has been saved and queued for upload.";
+    await _logAndSave(data: data, status: 'Queued', message: successMessage, apiResults: [], ftpStatuses: [], serverName: serverName, finalImageFiles: {});
+
+    return {'success': true, 'message': successMessage};
+  }
+
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(TarballSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
     final stationCode = data.selectedStation?['tbl_station_code'] ?? 'NA';
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
     final baseFileName = '${stationCode}_$fileTimestamp';
@@ -82,7 +241,6 @@ class MarineTarballSamplingService {
       module: 'marine',
       subModule: 'marine_tarball_sampling',
     );
-
     final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
     if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
       await localSubmissionDir.create(recursive: true);
@@ -93,7 +251,6 @@ class MarineTarballSamplingService {
       baseFileName: baseFileName,
       destinationDir: localSubmissionDir,
     );
-
     Map<String, dynamic> ftpDataResult = {'success': true, 'statuses': []};
     if (dataZip != null) {
       ftpDataResult = await _submissionFtpService.submit(
@@ -104,11 +261,10 @@ class MarineTarballSamplingService {
     }
 
     final imageZip = await _zippingService.createImageZip(
-      imageFiles: finalImageFiles.values.toList(),
+      imageFiles: imageFiles.values.toList(),
       baseFileName: baseFileName,
       destinationDir: localSubmissionDir,
     );
-
     Map<String, dynamic> ftpImageResult = {'success': true, 'statuses': []};
     if (imageZip != null) {
       ftpImageResult = await _submissionFtpService.submit(
@@ -117,37 +273,15 @@ class MarineTarballSamplingService {
         remotePath: '/${p.basename(imageZip.path)}',
       );
     }
-    final bool ftpSuccess = (ftpDataResult['success'] == true && ftpImageResult['success'] == true);
 
-    // --- Step 3: Finalize and Log ---
-    String finalStatus;
-    String finalMessage;
-    if (apiSuccess) {
-      finalStatus = ftpSuccess ? 'S4' : 'S3';
-      finalMessage = ftpSuccess ? 'Data submitted successfully.' : 'Data sent to API. FTP upload failed/queued.';
-    } else {
-      finalStatus = ftpSuccess ? 'L4' : 'L1';
-      finalMessage = ftpSuccess ? 'API failed, but files sent to FTP.' : 'All submission attempts failed.';
-    }
-
-    await _logAndSave(
-        data: data,
-        status: finalStatus,
-        message: finalMessage,
-        apiResults: [apiDataResult, apiImageResult], // Log results from both API steps
-        ftpStatuses: [...ftpDataResult['statuses'], ...ftpImageResult['statuses']],
-        serverName: serverName,
-        finalImageFiles: finalImageFiles
-    );
-
-    if (apiSuccess || ftpSuccess) {
-      _handleTarballSuccessAlert(data, appSettings, isDataOnly: !apiSuccess);
-    }
-
-    return {'success': apiSuccess || ftpSuccess, 'message': finalMessage, 'reportId': data.reportId};
+    return {
+      'statuses': <Map<String, dynamic>>[
+        ...(ftpDataResult['statuses'] as List),
+        ...(ftpImageResult['statuses'] as List),
+      ],
+    };
   }
 
-  // Added a helper to reduce code duplication in the main submit method
   Future<void> _logAndSave({
     required TarballSamplingData data,
     required String status,
diff --git a/lib/services/retry_service.dart b/lib/services/retry_service.dart
index 05c2c79..1d14b00 100644
--- a/lib/services/retry_service.dart
+++ b/lib/services/retry_service.dart
@@ -3,42 +3,74 @@
 import 'dart:convert';
 import 'dart:io';
 import 'package:flutter/foundation.dart';
+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/services/api_service.dart';
 import 'package:environment_monitoring_app/services/base_api_service.dart';
 import 'package:environment_monitoring_app/services/ftp_service.dart';
-// START CHANGE: Added imports to get server configurations
 import 'package:environment_monitoring_app/services/server_config_service.dart';
-// END CHANGE
+import 'package:environment_monitoring_app/auth_provider.dart';
 
-/// A dedicated service to manage the queue of failed API and FTP requests
-/// for manual resubmission.
+/// A dedicated service to manage the queue of failed API, FTP, and complex submission tasks.
 class RetryService {
-  // Use singleton instances to avoid re-creating services unnecessarily.
   final DatabaseHelper _dbHelper = DatabaseHelper();
   final BaseApiService _baseApiService = BaseApiService();
   final FtpService _ftpService = FtpService();
-  // START CHANGE: Add instance of ServerConfigService
   final ServerConfigService _serverConfigService = ServerConfigService();
-  // END CHANGE
+
+  // --- START: MODIFICATION FOR HANDLING COMPLEX TASKS ---
+  // These services will be provided after the RetryService is created.
+  MarineInSituSamplingService? _marineInSituService;
+  RiverInSituSamplingService? _riverInSituService; // ADDED
+  AuthProvider? _authProvider;
+
+  // Call this method from your main app setup to provide the necessary services.
+  void initialize({
+    required MarineInSituSamplingService marineInSituService,
+    required RiverInSituSamplingService riverInSituService, // ADDED
+    required AuthProvider authProvider,
+  }) {
+    _marineInSituService = marineInSituService;
+    _riverInSituService = riverInSituService; // ADDED
+    _authProvider = authProvider;
+  }
+  // --- END: MODIFICATION FOR HANDLING COMPLEX TASKS ---
+
+
+  /// Adds a generic, complex task to the queue, to be handled by a background processor.
+  Future<void> queueTask({
+    required String type,
+    required Map<String, dynamic> payload,
+  }) async {
+    await _dbHelper.queueFailedRequest({
+      'type': type,
+      'endpoint_or_path': 'N/A',
+      'payload': jsonEncode(payload),
+      'timestamp': DateTime.now().toIso8601String(),
+      'status': 'pending',
+    });
+    debugPrint("Task of type '$type' has been queued for background processing.");
+  }
 
   /// Adds a failed API request to the local database queue.
   Future<void> addApiToQueue({
     required String endpoint,
-    required String method, // e.g., 'POST' or 'POST_MULTIPART'
+    required String method,
     Map<String, dynamic>? body,
     Map<String, String>? fields,
     Map<String, File>? files,
   }) async {
-    // We must convert File objects to their string paths before saving to JSON.
     final serializableFiles = files?.map((key, value) => MapEntry(key, value.path));
-
     final payload = {
       'method': method,
       'body': body,
       'fields': fields,
       'files': serializableFiles,
     };
-
     await _dbHelper.queueFailedRequest({
       'type': 'api',
       'endpoint_or_path': endpoint,
@@ -83,11 +115,68 @@ class RetryService {
     final payload = jsonDecode(task['payload'] as String);
 
     try {
-      if (task['type'] == 'api') {
+      if (_authProvider == null) {
+        debugPrint("RetryService has not been initialized. Cannot process task.");
+        return false;
+      }
+
+      if (task['type'] == 'insitu_submission') {
+        debugPrint("Retrying complex task 'insitu_submission' with ID $taskId.");
+        if (_marineInSituService == 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
+          return false;
+        }
+
+        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);
+
+        final result = await _marineInSituService!.submitInSituSample(
+          data: dataToResubmit,
+          appSettings: _authProvider!.appSettings,
+          authProvider: _authProvider!,
+          logDirectory: logDirectoryPath,
+        );
+        success = result['success'];
+
+        // --- START: ADDED LOGIC FOR RIVER IN-SITU SUBMISSION ---
+      } else if (task['type'] == '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
+          return false;
+        }
+
+        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,
+          appSettings: _authProvider!.appSettings,
+          authProvider: _authProvider!,
+          logDirectory: logDirectoryPath,
+        );
+        success = result['success'];
+        // --- END: ADDED LOGIC FOR RIVER IN-SITU SUBMISSION ---
+
+      } else if (task['type'] == 'api') {
         final endpoint = task['endpoint_or_path'] as String;
         final method = payload['method'] as String;
-
-        // START CHANGE: Fetch the current active base URL to perform the retry
         final baseUrl = await _serverConfigService.getActiveApiUrl();
         debugPrint("Retrying API task $taskId: $method to $baseUrl/$endpoint");
         Map<String, dynamic> result;
@@ -96,42 +185,31 @@ class RetryService {
           final Map<String, String> fields = Map<String, String>.from(payload['fields'] ?? {});
           final Map<String, File> files = (payload['files'] as Map<String, dynamic>?)
               ?.map((key, value) => MapEntry(key, File(value as String))) ?? {};
-
           result = await _baseApiService.postMultipart(baseUrl: baseUrl, endpoint: endpoint, fields: fields, files: files);
-        } else { // Assume 'POST'
+        } else {
           final Map<String, dynamic> body = Map<String, dynamic>.from(payload['body'] ?? {});
           result = await _baseApiService.post(baseUrl, endpoint, body);
         }
-        // END CHANGE
-
         success = result['success'];
 
       } else if (task['type'] == '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");
 
         if (await localFile.exists()) {
-          // START CHANGE: On retry, attempt to upload to ALL available FTP servers.
           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
-            );
+            final result = await _ftpService.uploadFile(config: config, fileToUpload: localFile, remotePath: remotePath);
             if (result['success']) {
               success = true;
-              break; // Stop on the first successful upload
+              break;
             }
           }
-          // END CHANGE
         } else {
           debugPrint("Retry failed for FTP task $taskId: Source file no longer exists at ${localFile.path}");
           success = false;
diff --git a/lib/services/river_in_situ_sampling_service.dart b/lib/services/river_in_situ_sampling_service.dart
index 6036e0c..81bd692 100644
--- a/lib/services/river_in_situ_sampling_service.dart
+++ b/lib/services/river_in_situ_sampling_service.dart
@@ -6,7 +6,7 @@ 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 path;
+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';
@@ -14,7 +14,10 @@ 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';
 
+import '../auth_provider.dart';
 import 'location_service.dart';
 import '../models/river_in_situ_sampling_data.dart';
 import '../bluetooth/bluetooth_manager.dart';
@@ -26,6 +29,7 @@ import 'zipping_service.dart';
 import 'submission_api_service.dart';
 import 'submission_ftp_service.dart';
 import 'telegram_service.dart';
+import 'retry_service.dart';
 
 
 class RiverInSituSamplingService {
@@ -38,6 +42,7 @@ class RiverInSituSamplingService {
   final LocalStorageService _localStorageService = LocalStorageService();
   final ServerConfigService _serverConfigService = ServerConfigService();
   final ZippingService _zippingService = ZippingService();
+  final RetryService _retryService = RetryService();
   final TelegramService _telegramService;
   final ImagePicker _picker = ImagePicker();
 
@@ -81,7 +86,7 @@ class RiverInSituSamplingService {
       final finalStationCode = stationCode ?? 'NA';
       final fileTimestamp = "${data.samplingDate}-${data.samplingTime}".replaceAll(':', '-');
       final newFileName = "${finalStationCode}_${fileTimestamp}_${imageInfo.replaceAll(' ', '')}.jpg";
-      final filePath = path.join(tempDir.path, newFileName);
+      final filePath = p.join(tempDir.path, newFileName);
 
       return File(filePath)..writeAsBytesSync(img.encodeJpg(originalImage));
 
@@ -154,44 +159,207 @@ class RiverInSituSamplingService {
     _serialManager.dispose();
   }
 
-  Future<Map<String, dynamic>> submitData(RiverInSituSamplingData data, List<Map<String, dynamic>>? appSettings) async {
+  Future<Map<String, dynamic>> submitData({
+    required RiverInSituSamplingData data,
+    required List<Map<String, dynamic>>? appSettings,
+    required AuthProvider authProvider,
+    String? logDirectory,
+  }) async {
     const String moduleName = 'river_in_situ';
-    final serverName = (await _serverConfigService.getActiveApiConfig())?['config_name'] as String? ?? 'Default';
 
+    final connectivityResult = await Connectivity().checkConnectivity();
+    bool isOnline = connectivityResult != 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...");
+      final bool transitionSuccess = await authProvider.checkAndTransitionToOnlineSession();
+      if (transitionSuccess) {
+        isOfflineSession = false;
+      } else {
+        isOnline = false;
+      }
+    }
+
+    if (isOnline && !isOfflineSession) {
+      debugPrint("Proceeding with direct ONLINE River In-Situ submission...");
+      return await _performOnlineSubmission(
+        data: data,
+        appSettings: appSettings,
+        moduleName: moduleName,
+        authProvider: authProvider,
+        logDirectory: logDirectory,
+      );
+    } else {
+      debugPrint("Proceeding with OFFLINE River In-Situ queuing mechanism...");
+      return await _performOfflineQueuing(
+        data: data,
+        moduleName: moduleName,
+      );
+    }
+  }
+
+  Future<Map<String, dynamic>> _performOnlineSubmission({
+    required RiverInSituSamplingData 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>();
 
-    final dataResult = await _submissionApiService.submitPost(
-      moduleName: moduleName,
-      endpoint: 'river/manual/sample',
-      body: data.toApiFormData(),
+    bool anyApiSuccess = false;
+    Map<String, dynamic> apiDataResult = {};
+    Map<String, dynamic> apiImageResult = {};
+
+    try {
+      apiDataResult = await _submissionApiService.submitPost(
+        moduleName: moduleName,
+        endpoint: 'river/manual/sample',
+        body: data.toApiFormData(),
+      );
+
+      if (apiDataResult['success'] == false &&
+          (apiDataResult['message'] as String?)?.contains('Unauthorized') == true) {
+        debugPrint("API submission failed with Unauthorized. Attempting silent relogin...");
+        final bool reloginSuccess = await authProvider.attemptSilentRelogin();
+
+        if (reloginSuccess) {
+          debugPrint("Silent relogin successful. Retrying data submission...");
+          apiDataResult = await _submissionApiService.submitPost(
+            moduleName: moduleName,
+            endpoint: 'river/manual/sample',
+            body: data.toApiFormData(),
+          );
+        }
+      }
+
+      if (apiDataResult['success'] == true) {
+        anyApiSuccess = true;
+        data.reportId = apiDataResult['data']?['r_man_id']?.toString();
+
+        if (data.reportId != null) {
+          if (finalImageFiles.isNotEmpty) {
+            apiImageResult = await _submissionApiService.submitMultipart(
+              moduleName: moduleName,
+              endpoint: 'river/manual/images',
+              fields: {'r_man_id': data.reportId!},
+              files: finalImageFiles,
+            );
+            if (apiImageResult['success'] != true) {
+              anyApiSuccess = false;
+            }
+          }
+        } else {
+          anyApiSuccess = false;
+          apiDataResult['message'] = 'API Error: Submission succeeded but did not return a record ID.';
+        }
+      }
+    } on SocketException catch (e) {
+      final errorMessage = "API submission failed with network error: $e";
+      debugPrint(errorMessage);
+      anyApiSuccess = false;
+      apiDataResult = {'success': false, 'message': errorMessage};
+      await _retryService.addApiToQueue(endpoint: 'river/manual/sample', method: 'POST', body: data.toApiFormData());
+      if (finalImageFiles.isNotEmpty && data.reportId != null) {
+        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());
+    }
+
+    Map<String, dynamic> ftpResults = {'statuses': []};
+    bool anyFtpSuccess = false;
+    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");
+      anyFtpSuccess = false;
+    }
+
+    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.';
+      finalStatus = 'S3';
+    } else if (!anyApiSuccess && anyFtpSuccess) {
+      finalMessage = 'API submission failed and was queued, but files were sent to FTP successfully.';
+      finalStatus = 'L4';
+    } else {
+      finalMessage = 'All submission attempts failed and have been queued for retry.';
+      finalStatus = 'L1';
+    }
+
+    await _logAndSave(
+      data: data,
+      status: finalStatus,
+      message: finalMessage,
+      apiResults: [apiDataResult, apiImageResult],
+      ftpStatuses: ftpResults['statuses'],
+      serverName: serverName,
+      logDirectory: logDirectory,
     );
 
-    if (dataResult['success'] != true) {
-      await _logAndSave(data: data, status: 'L1', message: dataResult['message']!, apiResults: [dataResult], ftpStatuses: [], serverName: serverName);
-      // FIX: Also return the status code for the UI
-      return {'status': 'L1', 'success': false, 'message': dataResult['message']};
+    if (overallSuccess) {
+      _handleSuccessAlert(data, appSettings, isDataOnly: finalImageFiles.isEmpty);
     }
 
-    final recordId = dataResult['data']?['r_man_id']?.toString();
-    if (recordId == null) {
-      await _logAndSave(data: data, status: 'L1', message: 'API Error: Missing record ID.', apiResults: [dataResult], ftpStatuses: [], serverName: serverName);
-      return {'status': 'L1', 'success': false, 'message': 'API Error: Missing record ID.'};
-    }
-    data.reportId = recordId;
+    return {
+      'status': finalStatus,
+      'success': overallSuccess,
+      'message': finalMessage,
+      'reportId': data.reportId
+    };
+  }
 
-    Map<String, dynamic> imageResult = {'success': true, 'message': 'No images to upload.'};
-    if (finalImageFiles.isNotEmpty) {
-      imageResult = await _submissionApiService.submitMultipart(
-        moduleName: moduleName,
-        endpoint: 'river/manual/images',
-        fields: {'r_man_id': recordId},
-        files: finalImageFiles,
-      );
-    }
-    final bool apiSuccess = imageResult['success'] == true;
+  Future<Map<String, dynamic>> _performOfflineQueuing({
+    required RiverInSituSamplingData data,
+    required String moduleName,
+  }) async {
+    final serverConfig = await _serverConfigService.getActiveApiConfig();
+    final serverName = serverConfig?['config_name'] as String? ?? 'Default';
 
+    data.submissionStatus = 'L1';
+    data.submissionMessage = 'Submission queued due to being offline.';
+
+    final String? localLogPath = await _localStorageService.saveRiverInSituSamplingData(data, serverName: serverName);
+
+    if (localLogPath == null) {
+      const message = "Failed to save submission to local device storage.";
+      await _logAndSave(data: data, status: 'Error', message: message, apiResults: [], ftpStatuses: [], serverName: serverName);
+      return {'status': 'Error', 'success': false, 'message': message};
+    }
+
+    await _retryService.queueTask(
+      type: 'river_insitu_submission',
+      payload: {
+        'module': moduleName,
+        'localLogPath': p.join(localLogPath, 'data.json'),
+        'serverConfig': serverConfig,
+      },
+    );
+
+    const successMessage = "No internet connection. Submission has been saved and queued for upload.";
+    return {'status': 'Queued', 'success': true, 'message': successMessage};
+  }
+
+  Future<Map<String, dynamic>> _generateAndUploadFtpFiles(RiverInSituSamplingData data, Map<String, File> imageFiles, String serverName, String moduleName) async {
     final stationCode = data.selectedStation?['sampling_station_code'] ?? 'UNKNOWN';
     final fileTimestamp = "${data.samplingDate}_${data.samplingTime}".replaceAll(':', '-').replaceAll(' ', '_');
     final baseFileName = "${stationCode}_$fileTimestamp";
@@ -202,7 +370,7 @@ class RiverInSituSamplingService {
       subModule: 'river_in_situ_sampling',
     );
 
-    final Directory? localSubmissionDir = logDirectory != null ? Directory(path.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
+    final Directory? localSubmissionDir = logDirectory != null ? Directory(p.join(logDirectory.path, data.reportId ?? baseFileName)) : null;
     if (localSubmissionDir != null && !await localSubmissionDir.exists()) {
       await localSubmissionDir.create(recursive: true);
     }
@@ -215,50 +383,25 @@ class RiverInSituSamplingService {
     Map<String, dynamic> ftpDataResult = {'success': true, 'statuses': []};
     if (dataZip != null) {
       ftpDataResult = await _submissionFtpService.submit(
-          moduleName: moduleName, fileToUpload: dataZip, remotePath: '/${path.basename(dataZip.path)}');
+          moduleName: moduleName, fileToUpload: dataZip, remotePath: '/${p.basename(dataZip.path)}');
     }
 
     final imageZip = await _zippingService.createImageZip(
-      imageFiles: finalImageFiles.values.toList(),
+      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: '/${path.basename(imageZip.path)}');
-    }
-    final bool ftpSuccess = (ftpDataResult['success'] == true && ftpImageResult['success'] == true);
-
-    String finalStatus;
-    String finalMessage;
-    if (apiSuccess) {
-      finalStatus = ftpSuccess ? 'S4' : 'S3';
-      finalMessage = ftpSuccess ? 'Data submitted successfully.' : 'Data sent to API. FTP upload failed/queued.';
-    } else {
-      finalStatus = ftpSuccess ? 'L4' : 'L1';
-      finalMessage = ftpSuccess ? 'API failed, but files sent to FTP.' : 'All submission attempts failed.';
+          moduleName: moduleName, fileToUpload: imageZip, remotePath: '/${p.basename(imageZip.path)}');
     }
 
-    await _logAndSave(
-        data: data,
-        status: finalStatus,
-        message: finalMessage,
-        apiResults: [dataResult, imageResult],
-        ftpStatuses: [...ftpDataResult['statuses'], ...ftpImageResult['statuses']],
-        serverName: serverName
-    );
-
-    if (apiSuccess || ftpSuccess) {
-      _handleSuccessAlert(data, appSettings, isDataOnly: !apiSuccess);
-    }
-
-    // FIX: Add the 'status' and 'reportId' keys to the return map for the UI.
     return {
-      'status': finalStatus,
-      'success': apiSuccess || ftpSuccess,
-      'message': finalMessage,
-      'reportId': data.reportId
+      'statuses': <Map<String, dynamic>>[
+        ...(ftpDataResult['statuses'] as List),
+        ...(ftpImageResult['statuses'] as List),
+      ],
     };
   }
 
@@ -269,10 +412,29 @@ class RiverInSituSamplingService {
     required List<Map<String, dynamic>> apiResults,
     required List<Map<String, dynamic>> ftpStatuses,
     required String serverName,
+    String? logDirectory,
   }) async {
     data.submissionStatus = status;
     data.submissionMessage = message;
-    await _localStorageService.saveRiverInSituSamplingData(data, serverName: serverName);
+
+    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);
+
+      final imageFilePaths = data.toApiImageFiles();
+      imageFilePaths.forEach((key, file) {
+        if (file != null) {
+          updatedLogData[key] = file.path;
+        }
+      });
+
+      await _localStorageService.updateRiverInSituLog(updatedLogData);
+    } else {
+      await _localStorageService.saveRiverInSituSamplingData(data, serverName: serverName);
+    }
 
     final imagePaths = data.toApiImageFiles().values.whereType<File>().map((f) => f.path).toList();
     final logData = {
diff --git a/pubspec.lock b/pubspec.lock
index 7a087ce..de95eb6 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -25,6 +25,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.13.0"
+  bcrypt:
+    dependency: "direct main"
+    description:
+      name: bcrypt
+      sha256: "9dc3f234d5935a76917a6056613e1a6d9b53f7fa56f98e24cd49b8969307764b"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.3"
   boolean_selector:
     dependency: transitive
     description:
diff --git a/pubspec.yaml b/pubspec.yaml
index a46043b..14ea1e6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -17,6 +17,9 @@ dependencies:
   http: ^1.2.1
   intl: ^0.18.1
 
+  # --- ADDED: For secure password hashing ---
+  bcrypt: ^1.1.3
+
   # --- Local Storage & Offline Capabilities ---
   shared_preferences: ^2.2.3
   sqflite: ^2.3.3
@@ -29,7 +32,6 @@ dependencies:
   flutter_svg: ^2.0.9
   google_fonts: ^6.1.0
   dropdown_search: ^5.0.6 # For searchable dropdowns in forms
-  # --- ADDED: For opening document URLs ---
   url_launcher: ^6.2.6
   flutter_pdfview: ^1.3.2
   dio: ^5.4.3+1
@@ -46,13 +48,10 @@ dependencies:
 
   # --- Added for In-Situ Sampling Module ---
   simple_barcode_scanner: ^0.3.0 # For scanning sample IDs
-  #flutter_blue_classic: ^0.0.3     # For Bluetooth sonde connection
-
   flutter_bluetooth_serial:
     git:
       url: https://github.com/PSTPSYCO/flutter_bluetooth_serial.git
       ref: my-edits
-
   usb_serial: ^0.5.2               # For USB Serial sonde connection