// pages/home/camera/index.js

import * as model from '../../../services/tf/model'

Page({

  /**
   * 页面的初始数据
   */
  data: {
    isAuth: false,
    src: '',
    fps: 0,
    predicting: false,
    cameraContext: null,
    cameraListener: null,
    lastTime: 0
  },

  /**
   * 生命周期函数--监听页面加载
   */
  onLoad(options) {
    this.setData({
      lastTime: Date.now()
    })
    this.initModel();
  },

  initModel: async function () {
    this.showLoadingToast();

    await model.load();

    this.hideLoadingToast();

    if (!model.isReady()) {
      wx.showToast({
        title: '网络连接异常',
        icon: 'none'
      });
    }
  },

  showLoadingToast: function () {
    wx.showLoading({
      title: '拼命加载模型',
    });
  },

  hideLoadingToast: function () {
    wx.hideLoading()
  },

  openCamera() {
    this.setData({
      cameraContext: wx.createCameraContext()
    })

    this.setData({
      cameraListener: this.data.cameraContext.onCameraFrame(frame => {
        this.executePredict(frame)
      })
    })
    this.data.cameraListener.start();
  },

  executePredict(frame) {
    if (!this.data.predicting && model.isReady()) {
      this.setData({
        predicting: true
      }, async () => {
        const now = Date.now()
        // model.predict(frame)
        // const predictionResults = await model.classify(frame)
        // console.log(now - this.data.lastTime);
        model.predict(frame)
        this.setData({
          predicting: false,
          fps: (1000 / (now - this.data.lastTime)).toFixed(2),
          lastTime: now
        })
      })
    }
  },

  openSetting() {
    const _this = this
    let promise = new Promise((resolve, reject) => {
      wx.showModal({
        title: '授权',
        content: '请先授权获取摄像头权限',
        success(res) {
          if (res.confirm) {
            wx.openSetting({
              success(res) {
                if (res.authSetting['scope.camera']) { // 用户打开了授权开关
                  resolve(true)
                } else { // 用户没有打开授权开关， 继续打开设置页面
                  _this.openSetting().then(res => {
                    resolve(true)
                  })
                }
              },
              fail(res) {
                console.log(res)
              }
            })
          } else if (res.cancel) {
            _this.openSetting().then(res => {
              resolve(true)
            })
          }
        }
      })
    })
    return promise;
  },

  /**
   * 生命周期函数--监听页面初次渲染完成
   */
  onReady() {
    const _this = this
    wx.getSetting({
      success: res => {
        if (res.authSetting['scope.camera']) {
          // 用户已经授权
          _this.setData({
            isAuth: true
          })
          _this.openCamera()
        } else {
          // 用户还没有授权，向用户发起授权请求
          wx.authorize({
            scope: 'scope.camera',
            success() { // 用户同意授权
              _this.setData({
                isAuth: true
              })
              _this.openCamera()
            },
            fail() { // 用户不同意授权
              _this.openSetting().then(res => {
                _this.setData({
                  isAuth: false
                })
              })
            }
          })
        }
      },
      fail: res => {
        console.log('获取用户授权信息失败')
      }
    })
  },

  /**
   * 生命周期函数--监听页面显示
   */
  onShow() {

  },

  /**
   * 生命周期函数--监听页面隐藏
   */
  onHide() {

  },

  /**
   * 生命周期函数--监听页面卸载
   */
  onUnload() {
    this.data.cameraListener.stop();
  },

  /**
   * 页面相关事件处理函数--监听用户下拉动作
   */
  onPullDownRefresh() {

  },

  /**
   * 页面上拉触底事件的处理函数
   */
  onReachBottom() {

  },

  /**
   * 用户点击右上角分享
   */
  onShareAppMessage() {

  }
})