import 'dart:async';
import 'dart:typed_data';

import 'package:flutter/services.dart';

/// 设备类，代表一个BLE设备
class BleDevice {
  final String id;
  final String name;
  final int rssi;

  BleDevice({required this.id, required this.name, required this.rssi});

  factory BleDevice.fromJson(Map<String, dynamic> json) {
    return BleDevice(
      id: json['id'] as String,
      name: json['name'] as String? ?? 'Unknown Device',
      rssi: json['rssi'] as int? ?? 0,
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'name': name,
      'rssi': rssi,
    };
  }

  @override
  String toString() => 'BleDevice(id: $id, name: $name, rssi: $rssi)';
}

/// 连接状态
enum ConnectionState {
  disconnected,
  connecting,
  connected,
  disconnecting,
  error
}

/// 事件类型
class EventType {
  static const String audioData = 'audio_data';
  static const String connectionState = 'connection_state';
  static const String scanResult = 'scan_result';
  static const String wakeupSignal = 'wakeup_signal';
}

/// 杰理BLE插件主类
class Jieli {
  static const MethodChannel _methodChannel = MethodChannel('com.yunqiinnovation.jieli');
  static const EventChannel _eventChannel = EventChannel('com.yunqiinnovation.jieli/events');
  
  /// 扫描结果流
  static final StreamController<List<BleDevice>> _scanController = 
      StreamController<List<BleDevice>>.broadcast();
  Stream<List<BleDevice>> get scanResults => _scanController.stream;
  
  /// 连接状态变化流
  static final StreamController<ConnectionState> _connectionController = 
      StreamController<ConnectionState>.broadcast();
  Stream<ConnectionState> get connectionState => _connectionController.stream;
  
  /// 音频数据流
  static final StreamController<Uint8List> _audioController = 
      StreamController<Uint8List>.broadcast();
  Stream<Uint8List> get audioDataStream => _audioController.stream;
  
  /// 唤醒信号流
  static final StreamController<bool> _wakeupController = 
      StreamController<bool>.broadcast();
  Stream<bool> get wakeupStream => _wakeupController.stream;

  /// 事件流订阅
  StreamSubscription? _eventSubscription;

  /// 构造函数，初始化平台通道和事件监听
  Jieli() {
    _setupEventListener();
  }

  /// 设置事件监听器
  void _setupEventListener() {
    _eventSubscription = _eventChannel.receiveBroadcastStream().listen(_handleEvent);
  }

  /// 处理来自原生平台的事件
  void _handleEvent(dynamic event) {
    if (event is! Map<dynamic, dynamic>) return;
    
    final eventData = Map<String, dynamic>.from(event);
    final String eventType = eventData['type'] as String;
    final dynamic data = eventData['data'];
    
    switch (eventType) {
      case EventType.scanResult:
        if (data is List<dynamic>) {
          final deviceList = data
              .map((item) => BleDevice.fromJson(Map<String, dynamic>.from(item)))
              .toList();
          _scanController.add(deviceList);
        }
        break;
      case EventType.connectionState:
        if (data is int && data >= 0 && data < ConnectionState.values.length) {
          _connectionController.add(ConnectionState.values[data]);
        }
        break;
      case EventType.audioData:
        if (data is Uint8List) {
          _audioController.add(data);
        }
        break;
      case EventType.wakeupSignal:
        if (data is bool) {
          _wakeupController.add(data);
        }
        break;
    }
  }

  /// 开始扫描BLE设备
  Future<bool> startScan({int scanTimeout = 10000}) async {
    final result = await _methodChannel.invokeMethod<bool>(
      'startScan',
      {'scanTimeout': scanTimeout},
    );
    return result ?? false;
  }

  /// 停止扫描BLE设备
  Future<bool> stopScan() async {
    final result = await _methodChannel.invokeMethod<bool>('stopScan');
    return result ?? false;
  }

  /// 连接到指定设备
  Future<bool> connect(String deviceId) async {
    final result = await _methodChannel.invokeMethod<bool>(
      'connect',
      {'deviceId': deviceId},
    );
    return result ?? false;
  }

  /// 断开连接
  Future<bool> disconnect() async {
    final result = await _methodChannel.invokeMethod<bool>('disconnect');
    return result ?? false;
  }

  /// 发送开始录音命令
  Future<bool> sendStartRecordingCommand() async {
    final result = await _methodChannel.invokeMethod<bool>('sendStartRecordingCommand');
    return result ?? false;
  }

  /// 发送停止录音命令
  Future<bool> sendStopRecordingCommand() async {
    final result = await _methodChannel.invokeMethod<bool>('sendStopRecordingCommand');
    return result ?? false;
  }

  /// 关闭插件，释放资源
  Future<void> dispose() async {
    await stopScan();
    await disconnect();
    _eventSubscription?.cancel();
    _scanController.close();
    _connectionController.close();
    _audioController.close();
    _wakeupController.close();
  }

  /// 检查蓝牙是否已启用
  Future<bool> isBluetoothEnabled() async {
    final result = await _methodChannel.invokeMethod<bool>('isBluetoothEnabled');
    return result ?? false;
  }

  /// 请求打开蓝牙
  Future<bool> requestBluetoothEnable() async {
    final result = await _methodChannel.invokeMethod<bool>('requestBluetoothEnable');
    return result ?? false;
  }
}