import 'package:firebase_messaging/firebase_messaging.dart';
import 'package:flutter/foundation.dart';
import '../api/api_client.dart';

/// Handles FCM token registration and foreground message display.
class FcmService {
  static final FirebaseMessaging _messaging = FirebaseMessaging.instance;

  /// Request permission and register/refresh the FCM token with the backend.
  static Future<void> init() async {
    final settings = await _messaging.requestPermission(
      alert: true,
      badge: true,
      sound: true,
    );
    if (settings.authorizationStatus == AuthorizationStatus.denied) return;

    final token = await _messaging.getToken();
    if (token != null) {
      await _sendTokenToBackend(token);
    }

    // Re-register when token refreshes
    _messaging.onTokenRefresh.listen(_sendTokenToBackend);

    // Foreground messages — just log for now; app uses in-app bell for real-time
    FirebaseMessaging.onMessage.listen((message) {
      debugPrint('[FCM] foreground: ${message.notification?.title}');
    });
  }

  static Future<void> _sendTokenToBackend(String token) async {
    try {
      await apiDio.patch('/users/me/profile', data: {'push_token': token});
    } catch (e) {
      debugPrint('[FCM] token upload error: $e');
    }
  }

  /// Clear push token on logout so stale tokens don't receive notifications.
  static Future<void> clearToken() async {
    try {
      await apiDio.patch('/users/me/profile', data: {'push_token': null});
      await _messaging.deleteToken();
    } catch (e) {
      debugPrint('[FCM] clear token error: $e');
    }
  }
}