// app.js
const mqtt = require('./utils/mqtt.min.js');
const { MQTT_CONFIG } = require('./utils/mqtt.config.js');

App({
  globalData: {
    mqttClient: null,
    isMQTTConnected: false,
    // 自定义导航栏相关数据
    navBarHeight: 0,      // 整个自定义导航栏总高度
    menuBottom: 0,        // 标题栏上下边距
    menuHeight: 0,        // 胶囊按钮高度
    statusBarHeight: 0    // 状态栏高度
  },

  onLaunch() {
    // 计算导航栏高度
    this.calcNavBarInfo();
    // 小程序启动时初始化MQTT连接
    this.initMQTT();
  },

  /**
   * 计算导航栏高度信息
   */
  calcNavBarInfo() {
    try {
      const systemInfo = wx.getSystemInfoSync();
      const menuButtonInfo = wx.getMenuButtonBoundingClientRect();

      // 核心计算公式
      const statusBarHeight = systemInfo.statusBarHeight;
      const menuBottom = menuButtonInfo.top - statusBarHeight;
      const navBarHeight = menuBottom * 2 + menuButtonInfo.height + statusBarHeight;

      this.globalData.statusBarHeight = statusBarHeight;
      this.globalData.navBarHeight = navBarHeight;
      this.globalData.menuBottom = menuBottom;
      this.globalData.menuHeight = menuButtonInfo.height;

      console.log('导航栏信息:', {
        statusBarHeight,
        menuBottom,
        menuHeight: menuButtonInfo.height,
        navBarHeight
      });
    } catch (error) {
      console.error('计算导航栏信息失败:', error);
      // 使用默认值
      this.globalData.statusBarHeight = 20;
      this.globalData.navBarHeight = 44;
      this.globalData.menuBottom = 4;
      this.globalData.menuHeight = 32;
    }
  },

  /**
   * 初始化MQTT连接
   */
  initMQTT() {
    const that = this;
    
    try {
      // 构建MQTT连接URL（微信小程序使用wxs协议）
      const url = `wxs://${MQTT_CONFIG.host}:${MQTT_CONFIG.port}/mqtt`;
      
      console.log('[MQTT] 正在连接服务器...', url);
      
      // 创建MQTT客户端
      const client = mqtt.connect(url, {
        clientId: MQTT_CONFIG.clientId,
        username: MQTT_CONFIG.username,
        password: MQTT_CONFIG.password,
        keepalive: MQTT_CONFIG.keepalive,
        reconnectPeriod: MQTT_CONFIG.reconnectPeriod,
        connectTimeout: MQTT_CONFIG.connectTimeout,
        will: MQTT_CONFIG.will
      });

      // 连接成功
      client.on('connect', () => {
        console.log('[MQTT] 连接成功');
        that.globalData.isMQTTConnected = true;
        that.globalData.mqttClient = client;

        // 订阅主题
        that.subscribeTopics(client);

        // 发布上线消息
        client.publish('device/status', JSON.stringify({
          device: 'SmartPetFeeder',
          status: 'online',
          timestamp: new Date().toISOString()
        }), { qos: 1, retain: true });
      });

      // 接收消息
      client.on('message', (topic, message) => {
        console.log(`[MQTT] 收到消息 - Topic: ${topic}, Message: ${message.toString()}`);
        
        // 将消息分发到各个页面
        that.handleMQTTMessage(topic, message);
      });

      // 连接断开
      client.on('disconnect', () => {
        console.log('[MQTT] 连接断开');
        that.globalData.isMQTTConnected = false;
      });

      // 错误处理
      client.on('error', (error) => {
        console.error('[MQTT] 连接错误:', error);
        that.globalData.isMQTTConnected = false;
      });

      // 重新连接
      client.on('reconnect', () => {
        console.log('[MQTT] 正在重新连接...');
      });

    } catch (error) {
      console.error('[MQTT] 初始化失败:', error);
    }
  },

  /**
   * 订阅MQTT主题
   */
  subscribeTopics(client) {
    if (!client || !client.connected) {
      console.error('[MQTT] 客户端未连接，无法订阅主题');
      return;
    }

    MQTT_CONFIG.topics.forEach(topic => {
      client.subscribe(topic, { qos: MQTT_CONFIG.qos }, (err) => {
        if (err) {
          console.error(`[MQTT] 订阅主题失败: ${topic}`, err);
        } else {
          console.log(`[MQTT] 订阅主题成功: ${topic}`);
        }
      });
    });
  },

  /**
   * 处理MQTT消息
   */
  handleMQTTMessage(topic, message) {
    // 将消息发送到当前显示的页面
    const pages = getCurrentPages();
    if (pages.length > 0) {
      const currentPage = pages[pages.length - 1];
      if (currentPage && typeof currentPage.onMQTTMessage === 'function') {
        currentPage.onMQTTMessage(topic, message);
      }
    }
  },

  /**
   * 发布MQTT消息
   */
  publishMQTT(topic, message, options = {}) {
    const client = this.globalData.mqttClient;
    
    if (!client || !client.connected) {
      console.error('[MQTT] 客户端未连接，无法发布消息');
      return false;
    }

    const defaultOptions = {
      qos: MQTT_CONFIG.qos,
      retain: false
    };

    const publishOptions = { ...defaultOptions, ...options };
    
    try {
      client.publish(topic, JSON.stringify(message), publishOptions);
      console.log(`[MQTT] 发布消息成功 - Topic: ${topic}`, message);
      return true;
    } catch (error) {
      console.error(`[MQTT] 发布消息失败 - Topic: ${topic}`, error);
      return false;
    }
  },

  /**
   * 断开MQTT连接
   */
  disconnectMQTT() {
    const client = this.globalData.mqttClient;
    
    if (client && client.connected) {
      // 发布离线消息
      client.publish('device/status', JSON.stringify({
        device: 'SmartPetFeeder',
        status: 'offline',
        timestamp: new Date().toISOString()
      }), { qos: 1, retain: true }, () => {
        client.end();
        this.globalData.isMQTTConnected = false;
        console.log('[MQTT] 已断开连接');
      });
    }
  },

  onHide() {
    // 小程序隐藏时可以选择断开连接（根据实际需求决定）
    // this.disconnectMQTT();
  },

  onError(msg) {
    console.error('[App] 错误:', msg);
  }
})