import 'dart:async';
import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter_dotenv/flutter_dotenv.dart';
import 'package:mobile_monitoring/core/firebase_options.dart';
import 'package:mobile_monitoring/core/constants/strings.dart';
import 'package:mobile_monitoring/core/theme/app_theme.dart';
import 'package:mobile_monitoring/ui/pages/splash_screen.dart';
import 'package:mobile_monitoring/ui/pages/login.dart';
import 'package:mobile_monitoring/ui/pages/home.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await dotenv.load(fileName: '.env');
  FlutterError.onError = (details) {
    FlutterError.presentError(details);
    debugPrint('FlutterError: ${details.exceptionAsString()}');
    debugPrint(details.stack?.toString());
  };

  await runZonedGuarded(
    () async {
      await Firebase.initializeApp(
        options: DefaultFirebaseOptions.currentPlatform,
      );
      // Disable reCAPTCHA for development
      FirebaseAuth.instance.setSettings(
        appVerificationDisabledForTesting: true,
      );
      runApp(const MyApp());
    },
    (error, stack) {
      debugPrint('Zoned error: $error');
      debugPrint(stack.toString());
    },
  );
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: AppStrings.appName,
      debugShowCheckedModeBanner: false,
      theme: AppTheme.lightTheme,
      navigatorObservers: [LoggingNavigatorObserver()],
      home: const SplashScreen(
        duration: Duration(seconds: 3),
        nextPage: AuthWrapper(),
      ),
      onGenerateRoute: (settings) {
        switch (settings.name) {
          case '/home':
            return MaterialPageRoute(
              builder: (context) => const HomePage(),
              settings: settings,
            );
          default:
            return null;
        }
      },
    );
  }
}

class LoggingNavigatorObserver extends NavigatorObserver {
  LoggingNavigatorObserver();

  @override
  void didPush(Route route, Route? previousRoute) {
    debugPrint('NAV push: ${route.settings.name ?? route.runtimeType}');
    super.didPush(route, previousRoute);
  }

  @override
  void didPop(Route route, Route? previousRoute) {
    debugPrint('NAV pop: ${route.settings.name ?? route.runtimeType}');
    super.didPop(route, previousRoute);
  }

  @override
  void didReplace({Route? newRoute, Route? oldRoute}) {
    debugPrint(
      'NAV replace: ${oldRoute?.settings.name ?? oldRoute?.runtimeType} -> ${newRoute?.settings.name ?? newRoute?.runtimeType}',
    );
    super.didReplace(newRoute: newRoute, oldRoute: oldRoute);
  }
}

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

  @override
  State<AuthWrapper> createState() => _AuthWrapperState();
}

class _AuthWrapperState extends State<AuthWrapper> {
  @override
  Widget build(BuildContext context) {
    return StreamBuilder<User?>(
      stream: FirebaseAuth.instance.authStateChanges(),
      builder: (context, snapshot) {
        // Show loading while checking auth state
        if (snapshot.connectionState == ConnectionState.waiting) {
          return const Scaffold(
            body: Center(child: CircularProgressIndicator()),
          );
        }

        // If user is logged in, show home page
        if (snapshot.hasData) {
          return const HomePage();
        }

        // If user is not logged in, show login page
        return const LoginPage();
      },
    );
  }
}