export default class MoveService {
  constructor(DOM) {
    if ((navigator.userAgent.match(/(phone|pad|pod|iPhone|iPod|ios|iPad|Android|Mobile|BlackBerry|IEMobile|MQQBrowser|JUC|Fennec|wOSBrowser|BrowserNG|WebOS|Symbian|Windows Phone)/i))) {
      this.DviceType = true
    } else {
      this.DviceType = false
    }
    this.movedom = null
    this.w = document.body.clientWidth
    this.h = document.body.clientHeight
    this.PX = 0
    this.PY = 0
    this.domw = 0
    this.domh = 0
    this.on(DOM)
  }

  /**
       * 移动
       */
  mousemove(event) {
    const e = event || window.event
    const x = this.DviceType ? e.touches[0].clientX : e.clientX
    const y = this.DviceType ? e.touches[0].clientY : e.clientY
    const mx = x - this.PX
    const my = y - this.PY
    const outx = this.w - this.domw
    const outy = this.h - this.domh
    this.movedom.style.left = `${mx}px`
    this.movedom.style.top = `${my}px`
    if (mx >= outx) {
      this.movedom.style.left = `${outx}px`
    }
    if (my >= outy) {
      this.movedom.style.top = `${outy}px`
    }
    if (mx <= 0) {
      this.movedom.style.left = '0px'
    }
    if (my <= 0) {
      this.movedom.style.top = '0px'
    }
  }

  /**
       * 鼠标按下
       */
  mousedown(event) {
    // 获取点击DOM
    const e = event || window.event
    if (this.DviceType) {
      this.PX = e.touches[0].clientX - this.movedom.offsetLeft
      this.PY = e.touches[0].clientY - this.movedom.offsetTop
      this.movedom.ontouchmove = this.mousemove.bind(this)
      this.movedom.ontouchend = this.mouseup.bind(this)
    } else {
      this.PX = e.clientX - this.movedom.offsetLeft
      this.PY = e.clientY - this.movedom.offsetTop
      this.movedom.onmousemove = this.mousemove.bind(this)
      this.movedom.onmouseup = this.mouseup.bind(this)
    }
  }

  /**
       * 鼠标松开
       */
  mouseup() {
    this.off()
  }

  /**
       * 监听鼠标
       * @param dom dom元素
       */
  on(dom) {
    this.movedom = dom
    try {
      if (this.DviceType) {
        this.movedom.ontouchstart = this.mousedown.bind(this)
      } else {
        this.movedom.onmousedown = this.mousedown.bind(this)
      }
      this.domw = parseInt(window.getComputedStyle(this.movedom).width)
      this.domh = parseInt(window.getComputedStyle(this.movedom).height)
    } catch (error) {
      console.warn('dom 获取失败')
    }
  }

  /**
       * 移除监听
       */
  off() {
    this.movedom.onmousemove = null
    this.movedom.onmouseup = null
    this.movedom.ontouchmove = null
    this.movedom.ontouchend = null
  }
}