import 'dart:async';

import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:miaoji_zhang/features/add/screenshot_parse_sheet.dart';
import 'package:miaoji_zhang/features/ai_mode/pages/ai_mode_page.dart';
import 'package:miaoji_zhang/features/auth/pages/login_page.dart';
import 'package:miaoji_zhang/features/auth/pages/register_page.dart';
import 'package:miaoji_zhang/features/auth/pages/splash_page.dart';
import 'package:miaoji_zhang/features/chat/chat_page.dart';
import 'package:miaoji_zhang/features/home/pages/home_page.dart';
import 'package:miaoji_zhang/features/home/pages/main_shell.dart';
import 'package:miaoji_zhang/features/home/pages/search_page.dart';
import 'package:miaoji_zhang/features/onboarding/pages/onboarding_page.dart';
import 'package:miaoji_zhang/features/settings/account_data_page.dart';
import 'package:miaoji_zhang/features/settings/appearance_page.dart';
import 'package:miaoji_zhang/features/settings/budget_page.dart';
import 'package:miaoji_zhang/features/settings/category_manage_page.dart';
import 'package:miaoji_zhang/features/settings/companion_page.dart';
import 'package:miaoji_zhang/features/settings/me_page.dart';
import 'package:miaoji_zhang/features/settings/push_settings_page.dart';
import 'package:miaoji_zhang/features/settings/recycle_bin_page.dart';
import 'package:miaoji_zhang/features/settings/recognition_batch_page.dart';
import 'package:miaoji_zhang/features/settings/legal_document_page.dart';
import 'package:miaoji_zhang/features/settings/screenshot_settings_page.dart';
import 'package:miaoji_zhang/features/settings/sync_conflicts_page.dart';
import 'package:miaoji_zhang/features/stats/report_page.dart';
import 'package:miaoji_zhang/features/stats/stats_page.dart';
import 'package:miaoji_zhang/features/add/add_page.dart';
import 'package:miaoji_zhang/shared/api/api_client.dart';
import 'package:miaoji_zhang/shared/api/auth_api.dart';
import 'package:miaoji_zhang/shared/api/config_api.dart';
import 'package:miaoji_zhang/shared/services/current_ledger_store.dart';
import 'package:miaoji_zhang/shared/services/recognition_import_service.dart';
import 'package:miaoji_zhang/shared/services/screenshot_channel.dart';
import 'package:miaoji_zhang/shared/services/sync_service.dart';
import 'package:miaoji_zhang/shared/services/session_store.dart';
import 'package:miaoji_zhang/shared/services/push_service.dart';
import 'package:miaoji_zhang/shared/theme/theme_store.dart';
import 'package:miaoji_zhang/shared/update/update_coordinator.dart';
import 'package:provider/provider.dart';
import 'package:miaoji_zhang/shared/theme/app_theme.dart';

final _rootNavigatorKey = GlobalKey<NavigatorState>();

final router = GoRouter(
  navigatorKey: _rootNavigatorKey,
  initialLocation: '/splash',
  refreshListenable: SessionStore.instance,
  redirect: (_, state) {
    final aiOnly =
        state.matchedLocation == '/ai-mode' ||
        state.matchedLocation == '/companion';
    if (aiOnly &&
        SessionStore.instance.isAccount &&
        !SessionStore.instance.aiEnabled) {
      return '/home';
    }
    return null;
  },
  routes: [
    GoRoute(path: '/splash', builder: (_, __) => const SplashPage()),
    GoRoute(
      path: '/login',
      builder: (_, state) =>
          LoginPage(notice: state.uri.queryParameters['notice']),
    ),
    GoRoute(path: '/register', builder: (_, __) => const RegisterPage()),
    GoRoute(path: '/onboarding', builder: (_, __) => const OnboardingPage()),
    GoRoute(path: '/add', builder: (_, __) => const AddPage()),
    GoRoute(path: '/budget', builder: (_, __) => const BudgetPage()),
    GoRoute(path: '/account-data', builder: (_, __) => const AccountDataPage()),
    GoRoute(path: '/appearance', builder: (_, __) => const AppearancePage()),
    GoRoute(
      path: '/notification-settings',
      builder: (_, __) => const PushSettingsPage(),
    ),
    GoRoute(path: '/recycle-bin', builder: (_, __) => const RecycleBinPage()),
    GoRoute(
      path: '/sync-conflicts',
      builder: (_, __) => const SyncConflictsPage(),
    ),
    GoRoute(path: '/companion', builder: (_, __) => const CompanionPage()),
    GoRoute(
      path: '/categories',
      builder: (_, __) => const CategoryManagePage(),
    ),
    GoRoute(
      path: '/report',
      builder: (_, state) => ReportPage(
        initialPeriod: state.uri.queryParameters['period'],
        initialAnchor: DateTime.tryParse(
          state.uri.queryParameters['date'] ?? '',
        ),
      ),
    ),
    GoRoute(
      path: '/legal/:kind',
      builder: (_, state) => LegalDocumentPage(
        kind: LegalDocumentKind.fromKey(state.pathParameters['kind']),
      ),
    ),
    GoRoute(path: '/search', builder: (_, __) => const SearchPage()),
    GoRoute(
      path: '/screenshot-settings',
      builder: (_, __) => const ScreenshotSettingsPage(),
    ),
    GoRoute(
      path: '/recognition-batches',
      builder: (_, state) => RecognitionBatchPage(
        initialBatchId: state.uri.queryParameters['batchId'],
      ),
    ),
    StatefulShellRoute.indexedStack(
      builder: (_, __, shell) => MainShell(shell: shell),
      branches: [
        StatefulShellBranch(
          routes: [
            GoRoute(path: '/home', builder: (_, __) => const HomePage()),
          ],
        ),
        StatefulShellBranch(
          routes: [
            GoRoute(path: '/stats', builder: (_, __) => const StatsPage()),
          ],
        ),
        StatefulShellBranch(
          routes: [
            GoRoute(path: '/chat', builder: (_, __) => const ChatTabPage()),
          ],
        ),
        StatefulShellBranch(
          routes: [GoRoute(path: '/me', builder: (_, __) => const MePage())],
        ),
      ],
    ),
    GoRoute(path: '/ai-mode', builder: (_, __) => const AiModePage()),
  ],
);

class MiaoJiApp extends StatefulWidget {
  const MiaoJiApp({super.key});

  @override
  State<MiaoJiApp> createState() => _MiaoJiAppState();
}

class _MiaoJiAppState extends State<MiaoJiApp> with WidgetsBindingObserver {
  bool _showingScreenshotSheet = false;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
    UpdateCoordinator.instance.bindNavigator(_rootNavigatorKey);
    ApiClient.sessionExpired.addListener(_handleSessionExpired);
    unawaited(_bootstrap());
    ScreenshotChannel.onScreenshotReady(
      _handleScreenshotReady,
      onError: _handleScreenshotError,
    );
    ScreenshotChannel.onRecognitionAction(_handleRecognitionAction);
    PushService.instance.setOpenHandler(_handlePushOpen);
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    ApiClient.sessionExpired.removeListener(_handleSessionExpired);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      _resumeServices();
    }
  }

  Future<void> _bootstrap() async {
    await _runSafely(ScreenshotChannel.cleanupStaleScreenshots);
    if (SessionStore.instance.hasSession) {
      await _runSafely(CurrentLedgerStore.instance.loadCached);
    }
    await _runSafely(_restoreRecognitionServices);
    await _runSafely(PushService.instance.initialize);
    if (mounted) setState(() {});
    unawaited(_refreshRemoteState());
  }

  Future<void> _resumeServices() async {
    unawaited(ApiClient.instance.probe());
    await _runSafely(_restoreRecognitionServices);
    await _runSafely(PushService.instance.refresh);
    unawaited(_refreshRemoteState());
  }

  Future<void> _restoreRecognitionServices() async {
    await RecognitionImportService.configureNativeContext();
    await ScreenshotChannel.ensureRecognitionKeepAlive();
    await RecognitionImportService.importAutomatic();
    unawaited(_runSafely(_importAfterAccessibilityReconnect));
  }

  Future<void> _importAfterAccessibilityReconnect() async {
    final status = await ScreenshotChannel.waitForAccessibilityConnection();
    if (status.accessibilityConnected) {
      await RecognitionImportService.importAutomatic();
    }
  }

  Future<void> _refreshRemoteState() async {
    await Future.wait([
      _runSafely(PublicConfigApi.init),
      _refreshAccountData(),
      _runSafely(SyncService.instance.run),
    ]);
    if (mounted) setState(() {});
  }

  Future<void> _refreshAccountData() async {
    final session = SessionStore.instance;
    if (!session.isAccount || session.shouldUseLocalOnly) return;
    await _runSafely(AuthApi.me);
    await _runSafely(
      () => CurrentLedgerStore.instance.ensureLoaded(force: true),
    );
  }

  Future<void> _runSafely(Future<void> Function() operation) async {
    try {
      await operation();
    } catch (_) {
      // Optional startup and refresh work is isolated from the local app shell.
    }
  }

  Future<void> _handleRecognitionAction(Map<String, dynamic> action) async {
    await Future<void>.delayed(const Duration(milliseconds: 180));
    final context = _rootNavigatorKey.currentContext;
    if (!mounted || context == null || !context.mounted) return;
    if (action['action'] == 'open_recognition_settings') {
      router.push('/screenshot-settings');
      return;
    }
    await RecognitionImportService.handleAction(context, action);
  }

  Future<void> _handlePushOpen(PushOpen open) async {
    await Future<void>.delayed(const Duration(milliseconds: 150));
    final context = _rootNavigatorKey.currentContext;
    if (!mounted || context == null || !context.mounted) return;
    if (!SessionStore.instance.isAccount && open.action == 'budget') {
      router.go('/login', extra: null);
      return;
    }
    switch (open.action) {
      case 'home':
        router.go('/home');
      case 'budget':
        router.push('/budget');
      case 'update':
        await UpdateCoordinator.instance.checkManually(context);
      case 'none':
        break;
    }
  }

  void _handleSessionExpired() {
    final context = _rootNavigatorKey.currentContext;
    if (context != null && context.mounted) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('云同步登录已过期，本地记账仍可使用；重新登录后可继续同步')),
      );
    }
  }

  void _handleScreenshotError(String message) {
    final context = _rootNavigatorKey.currentContext;
    if (!mounted || context == null || !context.mounted) return;
    ScaffoldMessenger.of(
      context,
    ).showSnackBar(SnackBar(content: Text(message)));
    if (message.contains('无障碍服务')) {
      router.push('/screenshot-settings');
    }
  }

  Future<void> _handleScreenshotReady(String path) async {
    if (_showingScreenshotSheet) return;
    await Future<void>.delayed(const Duration(milliseconds: 150));
    final context = _rootNavigatorKey.currentContext;
    if (!mounted || context == null || !context.mounted) return;

    _showingScreenshotSheet = true;
    try {
      await ScreenshotParseSheet.show(context, path);
    } finally {
      _showingScreenshotSheet = false;
    }
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: ThemeStore.instance,
      builder: (context, _) => ChangeNotifierProvider.value(
        value: CurrentLedgerStore.instance,
        child: MaterialApp.router(
          title: PublicConfigApi.appName,
          theme: AppTheme.light,
          darkTheme: AppTheme.dark,
          themeMode: ThemeStore.instance.themeMode,
          routerConfig: router,
          debugShowCheckedModeBanner: false,
        ),
      ),
    );
  }
}