// lib/services/ftp_service.dart

import 'dart:io';
import 'package:flutter/foundation.dart';
import 'package:ftpconnect/ftpconnect.dart';
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';
// --- ADDED: Import for the local database helper ---
import 'package:environment_monitoring_app/services/api_service.dart';

class FtpService {
  final ServerConfigService _serverConfigService = ServerConfigService();
  // --- REMOVED: This creates an infinite loop with RetryService ---
  // final RetryService _retryService = RetryService();
  final DatabaseHelper _dbHelper = DatabaseHelper(); // --- ADDED: Instance of DatabaseHelper to get all configs ---

  /// Uploads a single file to the active server's FTP.
  ///
  /// [fileToUpload] The local file to be uploaded.
  /// [remotePath] The destination path on the FTP server (e.g., '/uploads/images/').
  /// Returns a map with 'success' and 'message' keys.
  // --- MODIFIED: Method now attempts to upload to multiple servers ---
  Future<Map<String, dynamic>> uploadFile(File fileToUpload, String remotePath) async {
    final configs = await _dbHelper.loadFtpConfigs() ?? []; // Get all FTP configs
    final latestConfigs = configs.take(2).toList(); // Limit to the two latest configs

    if (latestConfigs.isEmpty) {
      return {'success': false, 'message': 'FTP credentials are not configured or selected.'};
    }

    // Loop through each of the two latest configurations and attempt to upload
    for (final configMap in latestConfigs) {
      final config = configMap['config_json']; // The data is nested under this key
      final ftpHost = config?['ftp_host'] as String?;
      final ftpUser = config?['ftp_user'] as String?;
      final ftpPass = config?['ftp_pass'] as String?;
      final ftpPort = config?['ftp_port'] as int? ?? 21;

      if (ftpHost == null || ftpUser == null || ftpPass == null) {
        debugPrint('FTP: Configuration is incomplete. Skipping to next server if available.');
        continue;
      }

      final ftpConnect = FTPConnect(
        ftpHost,
        user: ftpUser,
        pass: ftpPass,
        port: ftpPort,
        showLog: kDebugMode, // Show logs only in debug mode
        timeout: 60, // --- MODIFIED: Set the timeout to 60 seconds ---
      );

      try {
        debugPrint('FTP: Connecting to $ftpHost...');
        await ftpConnect.connect();

        debugPrint('FTP: Uploading file ${fileToUpload.path} to $remotePath...');
        bool res = await ftpConnect.uploadFileWithRetry(
          fileToUpload,
          pRemoteName: remotePath,
          pRetryCount: 3, // --- MODIFIED: Retry three times on failure ---
        );

        await ftpConnect.disconnect(); // Disconnect immediately upon success
        if (res) {
          debugPrint('FTP upload to $ftpHost succeeded.');
          return {'success': true, 'message': 'File uploaded successfully via FTP.'};
        } else {
          debugPrint('FTP upload to $ftpHost failed after retries. Trying next server.');
          continue; // Move to the next configuration in the loop
        }
      } catch (e) {
        debugPrint('FTP upload to $ftpHost failed with an exception. Trying next server. Error: $e');
        try {
          // Attempt to disconnect even if an error occurred during connect/upload
          await ftpConnect.disconnect();
        } catch (_) {
          // Ignore errors during disconnect
        }
        continue; // Move to the next configuration in the loop
      }
    }

    // If the loop completes and no server was successful, queue for manual retry.
    final retryService = RetryService();
    debugPrint('All FTP upload attempts failed. Queueing for manual retry.');
    await retryService.addFtpToQueue(
        localFilePath: fileToUpload.path,
        remotePath: remotePath
    );
    return {'success': false, 'message': 'All FTP upload attempts failed and have been queued for manual retry.'};
  }
}