import 'package:convex_flutter/convex_flutter.dart';

void main() {
  runApp(const MyApp());
}

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

  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
      future: ConvexClient.initialize(
        ConvexConfig(
          deploymentUrl: 'https://your-app.convex.cloud',
          clientId: 'flutter-app-1.0',
        ),
      ),
      builder: (context, snapshot) {
        if (snapshot.hasError) {
          return ErrorWidget(snapshot.error!);
        }
        return const MaterialApp(home: HomeScreen());
      },
    );
  }
}

ConvexConfig(
  deploymentUrl: 'https://your-app.convex.cloud',  // Required
  clientId: 'flutter-app',                          // Optional, defaults to 'flutter-client'
  operationTimeout: Duration(seconds: 30),          // Optional, default 30s
  healthCheckQuery: 'health:ping',                  // Optional
)

// Query returns JSON string
final result = await ConvexClient.instance.query('tasks:list', {'limit': '10'});
final decoded = jsonDecode(result);

// Mutations execute with transactional guarantees
await ConvexClient.instance.mutation(
  name: 'tasks:create',
  args: {'title': 'Buy milk', 'completed': false},
);

// Actions for side effects (external API calls, etc)
final result = await ConvexClient.instance.action(
  name: 'openai:chat',
  args: {'prompt': 'Hello'},
);

SubscriptionHandle? _subscription;

_subscription = await ConvexClient.instance.subscribe(
  name: 'messages:list',
  args: {'channelId': 'general'},
  onUpdate: (value) {
    final data = jsonDecode(value);
    setState(() => _messages = data);
  },
  onError: (message, value) {
    debugPrint('Subscription error: $message');
  },
);

// Cancel when done
_subscription?.cancel();

await ConvexClient.instance.setAuth(token: 'your-jwt-token');
await ConvexClient.instance.setAuth(token: null);  // Clear

final authHandle = await ConvexClient.instance.setAuthWithRefresh(
  fetchToken: () async {
    return await FirebaseAuth.instance.currentUser?.getIdToken();
  },
  onAuthChange: (isAuthenticated) {
    print('Auth state: $isAuthenticated');
  },
);

authHandle.dispose();  // Sign out

ConvexClient.instance.authState.listen((isAuthenticated) {
  setState(() => _isLoggedIn = isAuthenticated);
});
bool isAuthenticated = ConvexClient.instance.isAuthenticated;

ConvexClient.instance.connectionState.listen((state) {
  if (state == WebSocketConnectionState.connected) {
    print('Connected');
  }
});

WebSocketConnectionState current = ConvexClient.instance.currentConnectionState;
bool isConnected = ConvexClient.instance.isConnected;

ConvexClient.instance.lifecycleEvents.listen((event) {
  if (event == AppLifecycleEvent.resumed) {
    ConvexClient.instance.reconnect();
  }
});

ConvexClient.instance.dispose();

try {
  await ConvexClient.instance.query('slowQuery', {});
} on TimeoutException {
  print('Operation timed out');
}