import 'ota_platform_interface.dart';
import 'dart:async';
import 'dart:typed_data';
import 'package:flutter/services.dart';
import 'package:get/get.dart';

class OtaEvent {
  static final int NOT_STARTED = -1; // 未开始
  static final int VALIDATION_FILE = 0; // 验证文件
  static final int ONUPGRADE = 1; // 升级中
  static final int START_UPGRADING = 2; // 开始升级
  static final int UPGRADE_SUCCESS = 3; // 升级成功
  static final int UPGRADE_FAILED = 4; // 升级失败
  static final int CONNECTION_DISCONNECTION = 5; // 连接断开
  static final int CONNECTION_SUCCESS = 6; // 连接成功

  /// 事件类型
  final String event;

  /// 输出升级状态
  final int? type;

  /// 输出升级进度
  final double? progress;

  /// 错误码 (仅在发生错误时有效)
  final int? code;

  /// 错误信息 (仅在发生错误时有效)
  final String? message;

  /// 构造函数
  OtaEvent({
    required this.event,
    this.type,
    this.progress,
    this.code,
    this.message,
  });

  /// 从Map构造对象
  factory OtaEvent.fromMap(Map<dynamic, dynamic> map) {
    return OtaEvent(
      event: map['event'],
      type: map['type'],
      progress: map['progress'],
      code: map['code'],
      message: map['message'],
    );
  }
}

class Ota {
  // 单例实例
  static final Ota _instance = Ota._internal();

  // 私有构造函数
  Ota._internal() {
    // 初始化时设置事件监听
    _setupEventListener();
  }

  // 公共访问点
  static Ota get instance => _instance;

  static const EventChannel _eventChannel = EventChannel(
    'com.example.ota/events',
  );
  final RxDouble progress = 0.0.obs;
  final RxInt type = OtaEvent.NOT_STARTED.obs;
  final RxBool isUpgrade = false.obs;

  /// 事件流
  Stream<OtaEvent>? _eventStream;
  bool _isEventListenerSet = false; // 防止重复监听

  /// 获取事件流
  Stream<OtaEvent> get eventStream {
    _eventStream ??= _eventChannel.receiveBroadcastStream().map((event) {
      if (event is Map) {
        return OtaEvent.fromMap(event);
      }
      throw PlatformException(code: 'INVALID_EVENT', message: '无效的事件数据');
    });
    return _eventStream!;
  }

  /// 释放资源
  void onClose() {
    onOtaClose();
    // 停止事件监听
    _eventStream = null;
    _isEventListenerSet = false;

    // 清理 Rx 对象
    progress.close();
    type.close();
    isUpgrade.value = false;
    print("Ota 对象资源已释放");
  }

  /// 内部设置事件监听（只执行一次）
  void _setupEventListener() {
    if (_isEventListenerSet) return;

    eventStream.listen((event) {
      if (event.event == 'onProgress' &&
          event.type != null &&
          event.progress != null) {
        print("flutter 收到数据${event.progress}type=${type.value}");
        progress.value = event.progress!;
        type.value = event.type!;
      }
      if (event.event == 'onStartOTA') {
        type.value = OtaEvent.START_UPGRADING;
        isUpgrade.value = true; // 开始升级
      }
      if (event.event == 'onStopOTA') {
        type.value = OtaEvent.UPGRADE_SUCCESS;
        isUpgrade.value = false;
      }
      if (event.event == 'onError' &&
          event.code != null &&
          event.message != null) {
        print("flutter onError${event.code}type=${event.message}");
        type.value = OtaEvent.UPGRADE_FAILED;
        isUpgrade.value = false;
      }
      if (event.event == 'NOCONNECTION') {
        type.value = OtaEvent.CONNECTION_DISCONNECTION;
        isUpgrade.value = false;
      }
      if (event.event == 'CONNECTION_SUCCESS') {
        type.value = OtaEvent.CONNECTION_SUCCESS;
      }
    });

    _isEventListenerSet = true;
  }

  Future<String?> searchDevices(String? filePath) {
    return OtaPlatform.instance.searchDevices(filePath);
  }

  Future<String?> onOtaClose() {
    return OtaPlatform.instance.onOtaClose();
  }
}