rmtPocketWatcher/flutter_app/lib/services/notification_service.dart

import 'package:flutter_local_notifications/flutter_local_notifications.dart';
import 'package:flutter/foundation.dart';

class NotificationService {
  static final NotificationService _instance = NotificationService._internal();
  factory NotificationService() => _instance;
  NotificationService._internal();

  final FlutterLocalNotificationsPlugin _notifications = FlutterLocalNotificationsPlugin();
  bool _initialized = false;

  Future<void> initialize() async {
    if (_initialized) return;

    try {
      // Android initialization
      const AndroidInitializationSettings androidSettings = AndroidInitializationSettings('@mipmap/ic_launcher');
      
      // iOS initialization
      const DarwinInitializationSettings iosSettings = DarwinInitializationSettings(
        requestAlertPermission: true,
        requestBadgePermission: true,
        requestSoundPermission: true,
      );

      // Linux/Windows initialization
      const LinuxInitializationSettings linuxSettings = LinuxInitializationSettings(
        defaultActionName: 'Open rmtPocketWatcher',
      );

      const InitializationSettings settings = InitializationSettings(
        android: androidSettings,
        iOS: iosSettings,
        linux: linuxSettings,
      );

      await _notifications.initialize(
        settings,
        onDidReceiveNotificationResponse: _onNotificationTapped,
      );

      _initialized = true;
      
      if (kDebugMode) {
        print('NotificationService initialized successfully');
      }
    } catch (e) {
      if (kDebugMode) {
        print('Failed to initialize notifications: $e');
      }
      // Don't throw - allow app to continue without notifications
    }
  }

  void _onNotificationTapped(NotificationResponse response) {
    // Handle notification tap if needed
    if (kDebugMode) {
      print('Notification tapped: ${response.payload}');
    }
  }

  Future<void> showPriceAlert({
    required String title,
    required String body,
    required double auecAmount,
    required double price,
    required String seller,
  }) async {
    if (!_initialized) await initialize();
    if (!_initialized) return; // Skip if initialization failed

    try {
      // Android notification details
      const AndroidNotificationDetails androidDetails = AndroidNotificationDetails(
        'price_alerts',
        'Price Alerts',
        channelDescription: 'Notifications for AUEC price alerts from rmtPocketWatcher',
        importance: Importance.high,
        priority: Priority.high,
        sound: RawResourceAndroidNotificationSound('notifcation'),
        icon: '@mipmap/ic_launcher',
        largeIcon: DrawableResourceAndroidBitmap('@mipmap/ic_launcher'),
        enableVibration: true,
        enableLights: true,
        showWhen: true,
      );

      // iOS notification details
      const DarwinNotificationDetails iosDetails = DarwinNotificationDetails(
        sound: 'notifcation.mp3', // iOS looks in main bundle, not assets
        presentAlert: true,
        presentBadge: true,
        presentSound: true,
        badgeNumber: 1,
        subtitle: 'Lambda Banking Conglomerate',
        threadIdentifier: 'price_alerts',
      );

      // Linux/Windows notification details
      final LinuxNotificationDetails linuxDetails = LinuxNotificationDetails(
        icon: AssetsLinuxIcon('assets/logo.png'),
        sound: AssetsLinuxSound('assets/notifcation.mp3'),
        category: LinuxNotificationCategory.imReceived,
        urgency: LinuxNotificationUrgency.critical,
      );

      final NotificationDetails details = NotificationDetails(
        android: androidDetails,
        iOS: iosDetails,
        linux: linuxDetails,
      );

      final int notificationId = DateTime.now().millisecondsSinceEpoch.remainder(100000);
      
      await _notifications.show(
        notificationId,
        title,
        body,
        details,
        payload: 'price_alert:$seller:$auecAmount:$price',
      );

      if (kDebugMode) {
        print('Price alert notification sent: $title - $body');
      }
    } catch (e) {
      if (kDebugMode) {
        print('Failed to show notification: $e');
      }
    }
  }

  Future<void> requestPermissions() async {
    if (!_initialized) await initialize();

    // Request permissions for iOS
    await _notifications
        .resolvePlatformSpecificImplementation<IOSFlutterLocalNotificationsPlugin>()
        ?.requestPermissions(
          alert: true,
          badge: true,
          sound: true,
        );

    // Request permissions for Android 13+
    await _notifications
        .resolvePlatformSpecificImplementation<AndroidFlutterLocalNotificationsPlugin>()
        ?.requestNotificationsPermission();
  }
}