import 'dart:async';
import 'package:flutter/services.dart';
import 'package:get/get.dart';
import 'package:permission_handler/permission_handler.dart';
import '../../core/utils/logger.dart';
import 'dart:io';

/// 蓝牙设备信息
class BluetoothDevice {
  final String name;
  final String address;
  final String type;

  BluetoothDevice({
    required this.name, 
    required this.address, 
    required this.type
  });

  factory BluetoothDevice.fromMap(Map<dynamic, dynamic> map) {
    return BluetoothDevice(
      name: map['name'] ?? '未知设备',
      address: map['address'] ?? '',
      type: map['type'] ?? 'unknown',
    );
  }

  @override
  String toString() => 'BluetoothDevice(name: $name, address: $address, type: $type)';
}

/// 经典蓝牙服务
/// 负责经典蓝牙设备的连接状态管理
class ClassicBluetoothService extends GetxService {
  static ClassicBluetoothService get to => Get.find<ClassicBluetoothService>();

  // 通道名称
  final _methodChannel = const MethodChannel('com.yunqiinnovation.classic_bluetooth/methods');
  final _eventChannel = const EventChannel('com.yunqiinnovation.classic_bluetooth/events');

  /// 当前连接的设备
  final currentDevice = Rx<BluetoothDevice?>(null);

  /// 已连接耳机设备列表
  final connectedDevices = <BluetoothDevice>[].obs;

  /// 蓝牙事件监听
  StreamSubscription? _eventSubscription;

  /// 蓝牙开关状态
  final bluetoothState = 'unknown'.obs;

  /// 蓝牙是否可用
  bool get isBluetoothEnabled => bluetoothState.value == 'on';

  /// 服务是否已初始化
  bool _isInitialized = false;

  /// 初始化蓝牙服务
  Future<bool> initialize() async {
    if (_isInitialized) {
      Logger.info('蓝牙服务已经初始化，跳过');
      return true;
    }

    try {
      Logger.info('正在初始化蓝牙服务...');

      // 检查蓝牙是否启用
      final bool isEnabled = await _methodChannel.invokeMethod<bool>('isBluetoothEnabled') ?? false;
      bluetoothState.value = isEnabled ? 'on' : 'off';
      Logger.info('初始蓝牙状态: ${bluetoothState.value}');

      // 设置事件监听
      _setupEventListener();

      _isInitialized = true;
      Logger.info('蓝牙服务初始化成功');
      
      // 如果蓝牙已启用，自动获取已连接设备
      if (isEnabled) {
        await refreshConnectedDevices();
      }
      
      return true;
    } catch (e) {
      Logger.error('初始化蓝牙服务失败: $e');
      return false;
    }
  }

  /// 设置事件监听
  void _setupEventListener() {
    _eventSubscription?.cancel();
    _eventSubscription = _eventChannel.receiveBroadcastStream().listen((event) {
      if (event is Map) {
        Logger.info('收到蓝牙事件: $event');
        
        // 根据事件类型处理
        final type = event['type'] as String?;
        if (type == 'stateChanged') {
          final state = event['state'] as String?;
          if (state != null) {
            _handleBluetoothStateChange(state);
          }
        } else if (type == 'deviceConnected') {
          final deviceMap = event['device'] as Map?;
          if (deviceMap != null) {
            _handleDeviceConnected(deviceMap);
          }
        } else if (type == 'deviceDisconnected') {
          final deviceMap = event['device'] as Map?;
          if (deviceMap != null) {
            _handleDeviceDisconnected(deviceMap);
          }
        }
      }
    }, onError: (e) {
      Logger.error('蓝牙事件监听错误: $e');
    });
  }


  /// 刷新已连接的蓝牙设备
  Future<bool> refreshConnectedDevices() async {
    // 确保服务已初始化
    if (!_isInitialized && !(await initialize())) {
      return false;
    }

    // 如果蓝牙未启用，无法获取设备
    if (!isBluetoothEnabled) {
      Logger.info('蓝牙未启用，无法获取设备');
      return false;
    }

    try {
      // 获取已连接的设备
      final devices = await getConnectedDevices();

      // 更新设备列表
      connectedDevices.value = devices;

      // 如果列表不为空且当前无选定设备，选择第一个
      if (devices.isNotEmpty && currentDevice.value == null) {
        currentDevice.value = devices.first;
      }

      return devices.isNotEmpty;
    } catch (e) {
      Logger.error('刷新已连接设备失败: $e');
      return false;
    }
  }

  /// 获取已连接的蓝牙设备
  Future<List<BluetoothDevice>> getConnectedDevices() async {
    try {
      // 确保服务已初始化
      if (!_isInitialized && !(await initialize())) {
        return [];
      }

      final result = await _methodChannel.invokeMethod('getConnectedDevices');

      if (result is List) {
        return result.map((device) => BluetoothDevice.fromMap(device)).toList();
      }

      return [];
    } catch (e) {
      Logger.error('获取已连接设备失败: $e');
      return [];
    }
  }

  /// 检查蓝牙是否已开启
  Future<bool> checkBluetoothEnabled() async {
    try {
      return await _methodChannel.invokeMethod<bool>('isBluetoothEnabled') ?? false;
    } catch (e) {
      Logger.error('检查蓝牙状态失败: $e');
      return false;
    }
  }

  /// 处理设备连接事件
  void _handleDeviceConnected(Map deviceMap) {
    final device = BluetoothDevice.fromMap(deviceMap);

    // 更新设备列表
    if (!connectedDevices.any((d) => d.address == device.address)) {
      connectedDevices.add(device);
    }

    // 更新当前设备
    currentDevice.value = device;

    Logger.info('设备已连接: ${device.name}');
  }

  /// 处理设备断开事件
  void _handleDeviceDisconnected(Map deviceMap) {
    final address = deviceMap['address'] as String?;

    if (address != null) {
      // 更新设备列表
      connectedDevices.removeWhere((d) => d.address == address);

      // 如果是当前设备，清除当前设备
      if (currentDevice.value?.address == address) {
        currentDevice.value = connectedDevices.isEmpty ? null : connectedDevices.first;
        Logger.info('当前设备已断开连接');
      }
    }
  }

  /// 处理蓝牙状态变化
  void _handleBluetoothStateChange(String state) {
    Logger.info('蓝牙状态变化: $state');

    // 更新蓝牙状态
    bluetoothState.value = state;

    if (state == 'off') {
      // 蓝牙关闭，清空设备信息
      connectedDevices.clear();
      currentDevice.value = null;
    } else if (state == 'on') {
      // 蓝牙重新开启，延迟一小段时间后刷新设备
      Future.delayed(const Duration(milliseconds: 1000), () {
        refreshConnectedDevices();
      });
    }
  }

  @override
  void onClose() {
    // 取消事件监听
    _eventSubscription?.cancel();
    super.onClose();
  }
}