// index.js
Page({
  data: {
    item: 0,
    tab: 0,
    playlist: [
      {
      id: 1,
      title: '热河',
      singer: '李志',
      src: 'http://localhost/1.mp3',
      coverImgUrl: '/images/Krt.png'
      }, 
      {
      id: 2,
      title: '这个世界会好吗',
      singer: '李志',
      src: 'http://localhost/2.mp3',
      coverImgUrl: '/images/Krt.png'
      }, 
      {
      id: 3,
      title: '关于郑州的记忆',
      singer: '李志',
      src: 'http://localhost/1.mp3',
      coverImgUrl: '/images/Krt.png'
      }, 
      {
      id: 4,
      title: '妈妈',
      singer: '李志',
      src: 'http://localhost/2.mp3',
      coverImgUrl: '/images/Krt.png'
      }
    ],
    state: 'paused',
    playIndex: 0,
    play: {
      currentTime: '00:00',
      duration: '00:00',
      percent: 0,
      title: '',
      singer: '',
      coverImgUrl: '/images/Krt.png',
    }
  },
  changeItem: function(e) {
    this.setData({
      item: e.target.dataset.item,
    })
  },
  changeTab: function(e) {
    this.setData({
      tab: e.detail.current
    })
  },
  audioCtx: null,
  onReady: function() {
    this.audioCtx = wx.createInnerAudioContext()
    this.setMusic(0)
    var that = this
    this.audioCtx.onError(function() {
      console.log('播放失败：' + that.audioCtx.src)
    })
    this.audioCtx.onEnded(function() {
      that.next()
    })
    this.audioCtx.onPlay(function() {})
    this.audioCtx.onTimeUpdate(function() {
      that.setData({
        'play.duration': formatTime(that.audioCtx.duration),
        'play.currentTime': formatTime(that.audioCtx.currentTime),
        'play.percent': that.audioCtx.currentTime / that.audioCtx.duration * 100
      })
    })
    function formatTime(time) {
      var minute = Math.floor(time / 60) % 60;
      var second = Math.floor(time) % 60
      return (minute < 10 ? '0' + minute : minute) + ':' + (second < 10 ? '0' + second : second)
    }
  },
  setMusic: function(index) {
    var music = this.data.playlist[index]
    this.audioCtx.src = music.src
    this.setData({
      playIndex: index,
      'play.title': music.title,
      'play.singer': music.singer,
      'play.coverImgUrl': music.coverImgUrl,
      'play.currentTime': '00:00',
      'play.duration': '00:00',
      'play.percent': 0
    })
  },
  play: function() {
    this.audioCtx.play()
    this.setData({
      state: 'running'
    })
  },
  pause: function() {
    this.audioCtx.pause()
    this.setData({
      state: 'paused'
    })
  },
  next: function() {
    var index = this.data.playIndex >= this.data.playlist.length - 1 ? 0 : this.data.playIndex + 1
    this.setMusic(index)
    if (this.data.state === 'running') {
      this.play()
    }
  },
  sliderChange: function(e) {
    var second = e.detail.value * this.audioCtx.duration / 100
    this.audioCtx.seek(second)
  },
  change: function(e) {
    this.setMusic(e.currentTarget.dataset.index)
    this.play()
  }
})