import 'dart:async';
import 'package:web_socket_channel/web_socket_channel.dart';

class WebSocketService {
  static final WebSocketService _instance = WebSocketService._();

  factory WebSocketService() => _instance;

  WebSocketService._();

  WebSocketChannel? _channel;

  final _messageController = StreamController<String>.broadcast();
  final _errorController = StreamController<Object>.broadcast();

  Stream<String> get messages => _messageController.stream;

  Stream<Object> get errors => _errorController.stream;

  bool get isConnected => _channel != null;

  void connect(String url) {
    if (_channel != null) return;

    _channel = WebSocketChannel.connect(Uri.parse(url));

    _channel!.stream.listen(
      (message) => _messageController.add(message.toString()),
      onError: (error) => _errorController.add(error),
      onDone: () => _errorController.add('WebSocket closed'),
    );
  }

  void send(String message) {
    if (_channel == null) {
      _errorController.add('WebSocket not connected');
      return;
    }
    _channel!.sink.add(message);
  }

  void disconnect() {
    _channel?.sink.close();
    _channel = null;
  }
}