import 'dart:async';

import 'package:gifunavi/model/destination.dart';
import 'package:gifunavi/utils/database_helper.dart';

class DatabaseService {
  // Private constructor
  DatabaseService._privateConstructor();

  // Static instance
  static final DatabaseService _instance =
      DatabaseService._privateConstructor();

  // Factory constructor to return the instance
  factory DatabaseService() {
    return _instance;
  }

  // StreamController for updates
  final StreamController<List<Destination>> _dbUpdateController =
      StreamController<List<Destination>>.broadcast();

  // Getter for the stream
  Stream<List<Destination>> get destinationUpdatesStream =>
      _dbUpdateController.stream;

  // Method to fetch destinations
  Future<List<Destination>> fetchDestinations() async {
    // Your database fetch logic here
    List<Destination> destinations = await _fetchFromDb();
    _dbUpdateController.add(destinations);
    return destinations;
  }

  // Method to update the database and emit an update through the stream
  Future<void> updateDatabase() async {
    // Your update logic here

    // After updating, fetch the updated list and add it to the stream
    fetchDestinations();
  }

  // Method to fetch data from the database (placeholder)
  Future<List<Destination>> _fetchFromDb() async {
    // Simulate fetching data with a delay
    DatabaseHelper db = DatabaseHelper.instance;
    List<Destination> destinations = await db.getDestinations();
    return destinations; // Replace with your actual fetch operation
  }

  // Dispose method to close the stream controller
  void dispose() {
    _dbUpdateController.close();
  }
}