import 'package:auth/auth.dart';
import 'package:firebase_messaging/firebase_messaging.dart';
import 'package:flutter/material.dart';
import 'package:flutter_localizations/flutter_localizations.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:legacy_theme/legacy_theme.dart';
import 'package:sf_app_platform/core/app_version_check/app_update_gate.dart';
import 'package:sf_app_platform/core/app_version_check/app_version_check.dart';
import 'package:sf_app_platform/core/config/app_mode.dart';
import 'package:sf_app_platform/navigation/app_router.dart';
import 'package:navigation/navigation.dart';
import 'package:sf_app_platform/providers/app_state_provider.dart';
import 'package:sf_app_platform/providers/permissions/permissions_provider.dart';
import 'package:sf_app_platform/providers/legacy_heartbeat_service.dart';
import 'package:sf_app_platform/providers/wallet_heartbeat_service.dart';
import 'package:get_it/get_it.dart';
import 'package:sf_infrastructure/sf_infrastructure.dart';
import 'package:sf_shared/sf_shared.dart';
import 'package:sf_tracking/sf_tracking.dart';
import 'package:sf_localizations/sf_localizations.dart';
import 'package:utils/utils.dart';
import 'package:fonts/fonts.dart';
import 'package:videocall_sdk/videocall_sdk.dart';

class SaveFamilyApp extends ConsumerStatefulWidget {
  const SaveFamilyApp({super.key});

  @override
  SaveFamilyAppState createState() => SaveFamilyAppState();
}

class SaveFamilyAppState extends ConsumerState<SaveFamilyApp>
    with WidgetsBindingObserver {
  WalletHeartbeatService? _walletHeartbeat;
  LegacyHeartbeatService? _legacyHeartbeat;
  SfRouterListener? _trackingRouterListener;
  WebSocketService? _webSocket;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);

    _trackingRouterListener = SfRouterListener(
      listenable: appRouter.routerDelegate,
      currentScreenName: () {
        final config = appRouter.routerDelegate.currentConfiguration;
        if (config.matches.isEmpty) return null;
        return config.last.route.name;
      },
      tracking: sfTracking,
    );

    if (isPaymentMode) {
      _walletHeartbeat = WalletHeartbeatService(
        repository: ref.read(treezorRepositoryProvider),
        sessionLocal: SessionLocalDatasourceImpl(),
        onError: () => appRouter.go(AppRoutes.scaTreezor),
      );
    }

    if (isLegacyMode) {
      _legacyHeartbeat = LegacyHeartbeatService(
        ref: ref,
        onUnauthorized: () {
          clearSessionData();
          appRouter.go(AppRoutes.legacyLogin);
        },
      );
      _webSocket = GetIt.I<WebSocketService>();
      appRouter.routerDelegate.addListener(_onRouteChanged);
    }

    onBeforeSessionCleared = () {
      _walletHeartbeat?.stop();
      _legacyHeartbeat?.stop();
      _webSocket?.disconnect();
      GetIt.I<VideocallClient>().logout();
      FirebaseMessaging.instance.deleteToken().catchError((Object e) {
        debugPrint('[FCM] deleteToken on logout failed: $e');
      });
    };
  }

  void _onRouteChanged() {
    final heartbeat = _legacyHeartbeat;
    if (heartbeat == null) return;

    final location = appRouter.routerDelegate.currentConfiguration.uri.path;
    if (location.startsWith(AppRoutes.legacyDashboard)) {
      heartbeat.start();
      _webSocket?.connect();
    } else {
      heartbeat.stop();
      _webSocket?.disconnect();
    }
  }

  @override
  void dispose() {
    if (isLegacyMode) {
      appRouter.routerDelegate.removeListener(_onRouteChanged);
    }
    _trackingRouterListener?.dispose();
    _walletHeartbeat?.stop();
    _legacyHeartbeat?.stop();
    _webSocket?.disconnect();
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    debugPrint('State: $state');
    ref.read(appLifecycleStateProvider.notifier).setState(state);
    if (state == AppLifecycleState.resumed) {
      _walletHeartbeat?.start();
      if (isLegacyMode) {
        _onRouteChanged();
      }
      ref.read(permissionsProvider.notifier).checkPermissions();
      ref.read(appVersionCheckProvider.notifier).refresh();
    } else if (state == AppLifecycleState.paused) {
      _walletHeartbeat?.stop();
      _legacyHeartbeat?.stop();
      _webSocket?.disconnect();
    }
    super.didChangeAppLifecycleState(state);
  }

  @override
  Widget build(BuildContext context) {
    SizeUtils.init(context: context);
    ref.watch(pushTokenRefreshListenerProvider);

    // Theme wiring:
    // - Legacy mode: new `legacy_theme` package (Material 3 + light/dark/system).
    // - Payment mode: unchanged behaviour (seed-based ColorScheme, light only).
    final ThemeData lightTheme;
    final ThemeData? darkTheme;
    final ThemeMode themeMode;
    if (isLegacyMode) {
      final legacyThemeState = ref.watch(legacyThemeNotifierProvider);
      lightTheme = LegacyAppTheme.light;
      darkTheme = LegacyAppTheme.dark;
      themeMode = legacyThemeState.themeMode;
    } else {
      lightTheme = ThemeData(
        fontFamily: AppFonts.stolzl,
        colorScheme: ColorScheme.fromSeed(seedColor: const Color(0xFF329E95)),
      );
      darkTheme = null;
      themeMode = ThemeMode.light;
    }

    return AppUpdateGate(
      child: MaterialApp.router(
        title: 'SaveFamily',
        theme: lightTheme,
        darkTheme: darkTheme,
        themeMode: themeMode,
        routerConfig: appRouter,
        debugShowCheckedModeBanner: false,
        localizationsDelegates: [
          SFLocalizations.delegate,
          GlobalMaterialLocalizations.delegate,
          GlobalCupertinoLocalizations.delegate,
          GlobalWidgetsLocalizations.delegate,
        ],
        supportedLocales: [for (final lang in supportedLanguages) Locale(lang)],
        localeResolutionCallback: (locale, supportedLocales) {
          if (locale == null) return supportedLocales.first;
          for (var supportedLocale in supportedLocales) {
            if (supportedLocale.languageCode == locale.languageCode) {
              return supportedLocale;
            }
          }
          return supportedLocales.first;
        },
      ),
    );
  }
}