import 'dart:async';

import 'package:flutter/widgets.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:supabase_flutter/supabase_flutter.dart';

import '../../features/auth/presentation/screens/forgot_password_screen.dart';
import '../../features/auth/presentation/screens/login_screen.dart';
import '../../features/auth/presentation/screens/signup_screen.dart';
import '../../features/admin/presentation/screens/admin_screen.dart';
import '../../features/discover/presentation/pages/discover_page.dart';
import '../../features/feed/presentation/screens/feed_screen.dart';
import '../../features/feed/presentation/screens/upload_post_screen.dart';
import '../../features/music/presentation/pages/music_page.dart';
import '../../features/profile/presentation/pages/profile_page.dart';
import '../../features/splash/presentation/pages/splash_page.dart';
import '../../features/theme_preview/presentation/pages/riotz_theme_preview_page.dart';
import '../supabase/supabase_providers.dart';
import 'app_routes.dart';

final appRouterProvider = Provider<GoRouter>((ref) {
  final client = ref.watch(supabaseProvider);
  final authStateStream = client.auth.onAuthStateChange;

  return GoRouter(
    initialLocation: AppRoutes.splash,
    refreshListenable: GoRouterRefreshStream(authStateStream),
    routes: [
      GoRoute(
        path: AppRoutes.splash,
        builder: (context, state) => const SplashPage(),
      ),
      GoRoute(
        path: AppRoutes.login,
        builder: (context, state) => const LoginScreen(),
      ),
      GoRoute(
        path: AppRoutes.signup,
        builder: (context, state) => const SignupScreen(),
      ),
      GoRoute(
        path: AppRoutes.forgotPassword,
        builder: (context, state) => const ForgotPasswordScreen(),
      ),
      GoRoute(
        path: AppRoutes.home,
        builder: (context, state) => const FeedScreen(),
      ),
      GoRoute(
        path: AppRoutes.uploadPost,
        builder: (context, state) => const UploadPostScreen(),
      ),
      GoRoute(
        path: AppRoutes.profile,
        builder: (context, state) => const ProfilePage(),
      ),
      GoRoute(
        path: AppRoutes.music,
        builder: (context, state) => const MusicPage(),
      ),
      GoRoute(
        path: AppRoutes.discover,
        builder: (context, state) => const DiscoverPage(),
      ),
      GoRoute(
        path: AppRoutes.admin,
        builder: (context, state) => const AdminScreen(),
      ),
      GoRoute(
        path: AppRoutes.themePreview,
        builder: (context, state) => const RiotzThemePreviewPage(),
      ),
    ],
    redirect: (context, state) {
      final isLoggedIn = client.auth.currentUser != null;
      final isSplash = state.matchedLocation == AppRoutes.splash;
      final isAuthRoute = state.matchedLocation == AppRoutes.login ||
          state.matchedLocation == AppRoutes.signup ||
          state.matchedLocation == AppRoutes.forgotPassword;

      if (!isLoggedIn && !isSplash && !isAuthRoute) {
        return AppRoutes.login;
      }

      if (isLoggedIn && (isSplash || isAuthRoute)) {
        return AppRoutes.home;
      }

      return null;
    },
  );
});

class GoRouterRefreshStream extends ChangeNotifier {
  GoRouterRefreshStream(Stream<AuthState> stream) {
    _subscription = stream.asBroadcastStream().listen((_) => notifyListeners());
  }

  late final StreamSubscription<AuthState> _subscription;

  @override
  void dispose() {
    _subscription.cancel();
    super.dispose();
  }
}