import 'package:didvan/models/notification_message.dart';
import 'package:didvan/services/app_home_widget/home_widget_repository.dart';
import 'package:didvan/services/app_initalizer.dart';
import 'package:didvan/services/auth/auth_api_service.dart';
import 'package:didvan/services/auth/token_storage.dart';
import 'package:didvan/services/notification/notification_service.dart';
import 'package:didvan/services/storage/storage.dart';
import 'package:firebase_messaging/firebase_messaging.dart';
import 'package:flutter/foundation.dart';

class FirebaseApi {
  static String? fcmToken;

  Future<void> initNotification() async {
    if (kIsWeb) {
      try {
        bool isSupported = await FirebaseMessaging.instance.isSupported();
        if (!isSupported) {
          if (kDebugMode) {
            print(
                "⚠️ مرورگر از نوتیفیکیشن پشتیبانی نمی‌کند. پروسه نوتیفیکیشن با موفقیت لغو شد تا از کرش جلوگیری شود.");
          }
          return;
        }
      } catch (e) {
        if (kDebugMode) print("Error checking FCM support: $e");
        return;
      }
    }

    try {
      final messaging = FirebaseMessaging.instance;

      NotificationSettings settings = await messaging.requestPermission(
        alert: true,
        announcement: true,
        badge: true,
        carPlay: false,
        criticalAlert: true,
        provisional: true,
        sound: true,
      );

      if (settings.authorizationStatus == AuthorizationStatus.authorized ||
          settings.authorizationStatus == AuthorizationStatus.provisional) {
        if (kIsWeb) {
          fcmToken = await messaging.getToken(
            vapidKey:
                "BMXHGd93t_htpS7c62ceuuLVVmia2cEDmqxp46g9Vt0B3OxNMKIqN9nupsUMtv2Vq8Yy2sQGIqgCm9FxUSKvssU",
          );
        } else {
          fcmToken = await messaging.getToken();
        }

        if (kDebugMode) {
          print("fCMToken: $fcmToken");
        }
      } else {
        if (kDebugMode) {
          print("User declined or has not accepted notification permissions");
        }
      }
    } catch (e) {
      if (kDebugMode) print("Error initializing notifications: $e");
    }

    try {
      final initMsg = await FirebaseMessaging.instance.getInitialMessage();
      if (initMsg != null) {
        if (kDebugMode)
          print("=== APP OPENED FROM NOTIFICATION (TERMINATED) ===");
        NotificationMessage data = NotificationMessage.fromJson(initMsg.data);
        HomeWidgetRepository.data = data;
      }
    } catch (e) {
      if (kDebugMode) print("Error handling initial message: $e");
    }

    FirebaseMessaging.onMessageOpenedApp.listen((initMsg) async {
      try {
        NotificationMessage data = NotificationMessage.fromJson(initMsg.data);
        HomeWidgetRepository.data = data;
        await Future.delayed(const Duration(milliseconds: 300));
        await HomeWidgetRepository.decideWhereToGoNotif();
        await StorageService.delete(
            key: 'notification${AppInitializer.createNotificationId(data)}');
      } catch (e) {
        if (kDebugMode) print("Error handling background message: $e");
      }
    });

    FirebaseMessaging.onMessage.listen((event) => handleMessage(event));

    // Push the current token to auth-service whenever it changes (Firebase
    // rotates it every few months, or after app reinstall, or after the
    // user clears app data). Without this we'd lose push delivery for
    // already-logged-in users until they explicitly logged in again.
    FirebaseMessaging.instance.onTokenRefresh.listen((newToken) async {
      fcmToken = newToken;
      await _syncTokenToServer(newToken);
    });

    // Also sync once on every cold start: covers the case where the user
    // already logged in on a previous build and the server has a stale or
    // missing token.
    if (fcmToken != null && fcmToken!.isNotEmpty) {
      await _syncTokenToServer(fcmToken!);
    }
  }

  /// Push the FCM token up to auth-service so push notifications can reach
  /// this device. Safely no-ops when the user isn't logged in (no userId
  /// yet) — we'll catch them on the next cold start once they sign in.
  Future<void> _syncTokenToServer(String token) async {
    try {
      final userId = TokenStorage.userId;
      if (userId == null || userId.isEmpty) {
        if (kDebugMode) {
          print('FCM token refresh: skipping — user not logged in yet');
        }
        return;
      }
      final result = await AuthApiService.instance.updateUser(
        id: userId,
        data: {'firebaseToken': token},
      );
      if (kDebugMode) {
        print('FCM token pushed to server: success=${result.isSuccess}');
      }
    } catch (e) {
      if (kDebugMode) print('FCM token sync failed: $e');
    }
  }

  void handleMessage(RemoteMessage? message) async {
    if (message == null) return;

    try {
      await NotificationService.showFirebaseNotification(message);
    } catch (e) {
      if (kDebugMode) print("Error showing local notification: $e");
    }
  }
}