import 'dart:async';

import 'package:event_bus/event_bus.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter_mm_core/im_core/model/model_conversation.dart';
import 'package:flutter_mm_core/im_core/model/model_message.dart';

import 'im_ad/im_ad_item.dart';
import 'im_ad/im_ad_manager.dart';
import 'im_ad/im_ad_provider.dart';
import 'model/im_message_resp.dart';

typedef EventCallback<T> = void Function(T event);

class ImMsgProvider with ChangeNotifier {
  static final ImMsgProvider _ins = ImMsgProvider._();

  factory ImMsgProvider() => _ins;

  ImMsgProvider._();
  int _unReadCount = 0;
  bool get hasUnreadCount => _unReadCount > 0;

  ModelConversationListResult? _curConversation;

  void setUnReadStatus(ModelConversationListResult resp) {
    _curConversation = resp;
    _unReadCount = resp.totalUnreadCount;
    int adUnReadCount = 0;
    int adMaxCount = resp.conversations.length ~/ 3 + 1;
    List<ImAdItem> adList = ImAdProvider().getAdList(ImAdManager.kPosListFeedNative);
    for (int i = 0; i < adMaxCount && i < adList.length; i++) {
      ImAdItem adItem = adList[i];
      if (ImAdProvider().isUnreadAd(adItem.id)) {
        adUnReadCount++;
      }
    }
    _unReadCount += adUnReadCount;
    notifyListeners();
  }

  //广告数据刷新,我的消息红点状态也要同步更新
  void unReadStatusUpdateByAds() {
    setUnReadStatus(_curConversation ?? ModelConversationListResult());
  }

  void setUnReadStatusFromAd() {
    setUnReadStatus(_curConversation ?? ModelConversationListResult());
  }
}

class IMMsgEvent {
  final ModelMessage? model;
  final bool isSuccess;

  IMMessageModel? get msgModel {
    if (model == null) return null;
    IMMessageModel convtModel = IMMessageModel.convertModel(model!);
    return convtModel;
  }

  IMMsgEvent(this.model, this.isSuccess);
}

class ImEventBus {
  //保存单例
  static final ImEventBus _instance = ImEventBus._internal();

  //工厂构造函数
  factory ImEventBus() => _instance;

  //初始化eventBus
  late EventBus _eventBus;

  ImEventBus._internal() {
    // 初始化
    _eventBus = EventBus();
  }

  /// 开启eventbus订阅
  StreamSubscription on<T>(EventCallback<T> callback) {
    StreamSubscription stream = _eventBus.on<T>().listen((event) {
      callback(event);
    });
    return stream;
  }

  /// 发送消息
  void emit(event) {
    _eventBus.fire(event);
  }

  /// 移除stream
  void off(StreamSubscription steam) {
    steam.cancel();
  }
}

var imEventBus = ImEventBus._instance;