<template>
  <div ref="wrapper">
    <slot></slot>
  </div>
</template>

<script type="text/ecmascript-6">
  import BScroll from 'better-scroll'

  export default {
    props: {
      probeType: {
        type: Number,
        default: 1
      },
      click: {
        type: Boolean,
        default: true
      },
      listenScroll: {
        type: Boolean,
        default: false
      },
      data: {
        type: Array,
        default: null
      },
      pullup: {
        type: Boolean,
        default: false
      },
      pulldown: {
        type: Boolean,
        default: false
      },
      beforeScroll: {
        type: Boolean,
        default: false
      },
      refreshDelay: {
        type: Number,
        default: 20
      },
      bounce: {
        type: Boolean,
        default: true
      }
    },
    mounted() {
      setTimeout(() => {
        this._initScroll()
      }, 20)
    },
    methods: {
      _initScroll() {
        if (!this.$refs.wrapper) {
          return
        }
        this.scroll = new BScroll(this.$refs.wrapper, {
          probeType: this.probeType,
          click: this.click,
          bounce:this.bounce
        })

        if (this.listenScroll) {
          let me = this
          this.scroll.on('scroll', (pos) => {
            me.$emit('scroll', pos)
          })
        }

        if (this.pullup) {
          this.scroll.on('scrollEnd', () => {
            if (this.scroll.y <= (this.scroll.maxScrollY + 10)) {
              // 滚动到底部
              this.$emit('pullup')
            }
          })
        }
        if (this.pulldown) {
          this.scroll.on('touchend', (pos) => {
            // 下拉动作
            if (pos.y > 50) {
              this.$emit('pulldown')
            }
          })
        }
        if (this.beforeScroll) {
          this.scroll.on('beforeScrollStart', () => {
            this.$emit('beforeScroll')
          })
        }
        // if (this.pos) {
        //   // this.$emit('beforeScroll')
        //   this.scroll.scrollTo(this.pos.x,this.pos.y)
        // }
      },
      disable() {
        this.scroll && this.scroll.disable()
      },
      enable() {
        this.scroll && this.scroll.enable()
      },
      refresh() {
        this.scroll && this.scroll.refresh()
      },
      scrollTo(x,y,time) {
        this.scroll && this.scroll.scrollTo(x,y,time)
      },
      scrollToElement(el,time){
        this.scroll && this.scroll.scrollToElement(el,time)
      },
      scrollToElement() {
        this.scroll && this.scroll.scrollToElement.apply(this.scroll, arguments)
      }
    },
    watch: {
      data() {
        setTimeout(() => {
          this.refresh()
        }, this.refreshDelay)
      }
    }
  }
</script>

<style scoped >

</style>