import 'dart:developer';

import 'package:flutter/material.dart';
import 'package:mnemo_cards_web_v2/di/user_scope/user_scope.dart';
import 'package:yx_scope_flutter/yx_scope_flutter.dart';
import 'package:yx_state_flutter/yx_state_flutter.dart';

import 'di/app_scope/app_scope_container.dart';
import 'di/app_scope/app_scope_holder.dart';
import 'domain/state/theme_state_manager.dart';
import 'main.dart' show scaffoldMessengerKey;
import 'presentation/theme/app_colors.dart';
import 'presentation/theme/app_theme.dart';
import 'package:mnemo_cards_common/mnemo_cards_common.dart';

/// Main application widget
///
/// Wraps the entire app in ScopeProviders for AppScope and UserScope
class App extends StatelessWidget {
  const App({
    required this.appScopeHolder,
    super.key,
  });

  final AppScopeHolder appScopeHolder;

  @override
  Widget build(BuildContext context) {
    return ScopeProvider<AppScopeContainer>(
      holder: appScopeHolder,
      child: ScopeBuilder<AppScopeContainer>.withPlaceholder(
        builder: (context, appScope) {
          return _AppInitializer(appScope: appScope);
        },
        placeholder: const _LoadingPlaceholder(message: 'Инициализация...'),
      ),
    );
  }
}

/// Initializes the app and handles auto-login
class _AppInitializer extends StatefulWidget {
  const _AppInitializer({required this.appScope});

  final AppScopeContainer appScope;

  @override
  State<_AppInitializer> createState() => _AppInitializerState();
}

class _AppInitializerState extends State<_AppInitializer> {
  bool _isInitialized = false;

  @override
  void initState() {
    super.initState();
    _initialize();
  }

  @override
  void didUpdateWidget(_AppInitializer oldWidget) {
    super.didUpdateWidget(oldWidget);
    // Rebuild when UserScope changes
    if (mounted) {
      setState(() {});
    }
  }

  /// Try Telegram Web App authentication
  /// Returns true if authentication was successful, false otherwise
  Future<bool> _tryTelegramWebAppAuth() async {
    try {
      log('Checking Telegram Web App authentication...', name: 'App');

      // Try to authenticate with Telegram Web App
      final user = await widget.appScope.authService.loginWithTelegramWebApp();

      if (user != null) {
        log('Telegram Web App authentication successful', name: 'App');

        // Create UserScope if it doesn't exist
        if (widget.appScope.userScopeHolder.scope == null) {
          await widget.appScope.userScopeHolder.create();
        }

        // Set authenticated user
        final userScope = widget.appScope.userScopeHolder.scope;
        if (userScope != null) {
          await userScope.userStateManager.setUser(user);
          // Notify router about auth change
          widget.appScope.userScopeHolder.notifyAuthChanged();
        }

        // Return true to indicate successful authentication
        return true;
      } else {
        log('Telegram Web App authentication not available or failed', name: 'App');
        return false;
      }
    } catch (e, s) {
      log('Error during Telegram Web App authentication', error: e, stackTrace: s);
      // Continue with normal flow - this is not a critical error
      return false;
    }
  }

  Future<void> _initialize() async {
    try {
      log('Starting app initialization...', name: 'App');

      // Try Telegram Web App authentication first
      final telegramAuthSuccess = await _tryTelegramWebAppAuth();

      // If Telegram Web App auth succeeded, skip normal auto-login
      // (tokens are already saved and user is set)
      if (telegramAuthSuccess) {
        log('Telegram Web App auth succeeded, skipping normal auto-login', name: 'App');
      } else {
        // Try auto-login with timeout
        log('Attempting auto-login...', name: 'App');
        UserDto? user;
        try {
          user = await widget.appScope.authService.autoLogin().timeout(
            const Duration(seconds: 3),
            onTimeout: () {
              log('Auto-login timed out, continuing as guest', name: 'App');
              return null;
            },
          );
        } catch (e) {
          log('Auto-login failed with error, continuing as guest', error: e, name: 'App');
          user = null;
        }

        // Create UserScope if needed
        if (widget.appScope.userScopeHolder.scope == null) {
          log('Creating UserScope...', name: 'App');
          await widget.appScope.userScopeHolder.create();
        }

        if (user != null) {
          log('Auto-login successful, setting user', name: 'App');
          await widget.appScope.userScopeHolder.scope!.userStateManager.setUser(user);
          // Notify router about auth change
          widget.appScope.userScopeHolder.notifyAuthChanged();
          log('UserScope created and user set', name: 'App');
        } else {
          log('No saved session, starting as guest', name: 'App');
        }
      }


      log('Setting _isInitialized = true', name: 'App');
      setState(() {
        _isInitialized = true;
      });
      log('App initialization completed', name: 'App');
    } catch (e) {
      log('Error during initialization', error: e, name: 'App');
      // Continue as guest even if auto-login fails
      log('Continuing as guest after error', name: 'App');
      setState(() {
        _isInitialized = true;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    log('_AppInitializer build called, _isInitialized: $_isInitialized', name: 'App');
    
    if (!_isInitialized) {
      log('Showing loading screen', name: 'App');
      return _LoadingScreen(appScope: widget.appScope, message: 'Loading...');
    }

    log('Building main app', name: 'App');
    return StateBuilder(
      stateReadable: widget.appScope.themeManager,
      builder: (context, themeState, _) {
        log('StateBuilder builder called with themeState: ${themeState.mode}', name: 'App');
        return _buildAppWithUserScope(themeState);
      },
    );
  }

  Widget _buildAppWithUserScope(ThemeState themeState) {
    Widget app = MaterialApp.router(
      title: 'Mnemo Cards',
      routerConfig: widget.appScope.router,
      theme: AppTheme.light,
      darkTheme: AppTheme.dark,
      themeMode: themeState.mode,
      scaffoldMessengerKey: scaffoldMessengerKey,
      debugShowCheckedModeBanner: false,
    );

    // Wrap with UserScope provider only if UserScope exists
    if (widget.appScope.userScopeHolder.scope != null) {
      return ScopeProvider<UserScope>(
        holder: widget.appScope.userScopeHolder,
        child: app,
      );
    }

    // For guest users, return app without UserScope provider
    return app;
  }
}

/// Плейсхолдер экрана загрузки (без доступа к теме)
class _LoadingPlaceholder extends StatelessWidget {
  const _LoadingPlaceholder({required this.message});

  final String message;

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: AppTheme.light,
      home: Scaffold(
        backgroundColor: AppTheme.light.scaffoldBackgroundColor,
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Image.asset(
                'assets/images/el_sol.png',
                width: 120,
                height: 120,
              ),
              const SizedBox(height: 24),
              Text(
                message,
                style: const TextStyle(
                  fontSize: 18,
                  fontWeight: FontWeight.w700,
                  color: AppColors.black,
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

/// Экран загрузки
class _LoadingScreen extends StatelessWidget {
  const _LoadingScreen({
    required this.appScope,
    required this.message,
  });

  final AppScopeContainer appScope;
  final String message;

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<ThemeState>(
      future: _getThemeState(),
      builder: (context, snapshot) {
        final themeState = snapshot.data ?? ThemeState(ThemeMode.system);
        final isDark = themeState.mode == ThemeMode.dark ||
            (themeState.mode == ThemeMode.system &&
             MediaQuery.platformBrightnessOf(context) == Brightness.dark);

        return MaterialApp(
          theme: AppTheme.light,
          darkTheme: AppTheme.dark,
          themeMode: themeState.mode,
          home: Scaffold(
            backgroundColor: isDark
                ? AppTheme.dark.scaffoldBackgroundColor
                : AppTheme.light.scaffoldBackgroundColor,
            body: Center(
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Image.asset(
                    isDark
                        ? 'assets/images/la_luna.png'
                        : 'assets/images/el_sol.png',
                    width: 120,
                    height: 120,
                  ),
                  const SizedBox(height: 24),
                  Text(
                    message,
                    style: TextStyle(
                      fontSize: 18,
                      fontWeight: FontWeight.w700,
                      color: isDark ? AppColors.white : AppColors.black,
                    ),
                  ),
                ],
              ),
            ),
          ),
        );
      },
    );
  }

  Future<ThemeState> _getThemeState() async {
    try {
      return appScope.themeManager.state;
    } catch (e) {
      // Fallback to system theme if themeManager is not available
      return ThemeState(ThemeMode.system);
    }
  }
}