// moveDialog.js代码
// v-dialogDrag: 弹窗拖拽+水平方向伸缩
import Vue from 'vue'
export default Vue.directive('dialogDrag', {

  bind (el) {
    // 弹框可拉伸最小宽高
    // console.log(el)
    const minWidth = 50
    const minHeight = 50
    // 初始非全屏
    let isFullScreen = false
    // 当前宽高
    let nowWidth = 0
    // eslint-disable-next-line no-unused-vars
    let nowHight = 0
    // 当前顶部高度
    let nowMarginTop = 20
    // 获取弹框头部（这部分可双击全屏）
    const dialogHeaderEl = el.querySelector('.el-dialog__header')
    // console.log(dialogHeaderEl)
    // 弹窗
    const dragDom = el.querySelector('.el-dialog')
    // 给弹窗加上overflow auto；不然缩小时框内的标签可能超出dialog；
    console.log(dragDom)
    dragDom.style.overflow = 'auto'
    // 清除选择头部文字效果
    // dialogHeaderEl.onselectstart = new Function("return false");
    // 头部加上可拖动cursor
    dialogHeaderEl.style.cursor = 'move'
    //

    // 获取原有属性 ie dom元素.currentStyle 火狐谷歌 window.getComputedStyle(dom元素, null);
    const sty = dragDom.currentStyle || window.getComputedStyle(dragDom, null)
    const moveDown = (e) => {
      console.log(e)
      // 鼠标按下，计算当前元素距离可视区的距离
      const disX = e.clientX - dialogHeaderEl.offsetLeft
      const disY = e.clientY - dialogHeaderEl.offsetTop
      // 获取到的值带px 正则匹配替换
      let styL, styT
      // 注意在ie中 第一次获取到的值为组件自带50% 移动之后赋值为px
      if (sty.left.includes('%')) {
        styL = +document.body.clientWidth * (+sty.left.replace(/%/g, '') / 100)
        styT = +document.body.clientHeight * (+sty.top.replace(/%/g, '') / 100)
      } else {
        styL = +sty.left.replace(/\px/g, '')
        styT = +sty.top.replace(/\px/g, '')
      };
      document.onmousemove = function (e) {
        console.log(e)
        // 通过事件委托，计算移动的距离
        const l = e.clientX - disX
        const t = e.clientY - disY
        // 移动当前元素
        dragDom.style.left = `${l + styL}px`
        dragDom.style.top = `${t + styT}px`
        // 将此时的位置传出去
        // binding.value({x:e.pageX,y:e.pageY})
      }
      document.onmouseup = function () {
        document.onmousemove = null
        document.onmouseup = null
      }
    }
    dialogHeaderEl.onmousedown = moveDown
    // 双击头部全屏效果
    dialogHeaderEl.ondblclick = () => {
      if (isFullScreen === false) {
        nowHight = dragDom.clientHeight
        nowWidth = dragDom.clientWidth
        nowMarginTop = dragDom.style.marginTop
        dragDom.style.left = 0
        dragDom.style.top = 0
        dragDom.style.height = '100VH'
        dragDom.style.width = '100VW'
        dragDom.style.marginTop = 0
        isFullScreen = true
        dialogHeaderEl.style.cursor = 'initial'
        dialogHeaderEl.onmousedown = null
      } else {
        dragDom.style.height = 'auto'
        dragDom.style.width = nowWidth + 'px'
        dragDom.style.marginTop = nowMarginTop
        isFullScreen = false
        dialogHeaderEl.style.cursor = 'move'
        dialogHeaderEl.onmousedown = moveDown
      }
    }
    dragDom.onmousemove = function (e) {
      if (e.clientX > dragDom.offsetLeft + dragDom.clientWidth - 10 || dragDom.offsetLeft + 10 > e.clientX) {
        dragDom.style.cursor = 'w-resize'
      } else if (el.scrollTop + e.clientY > dragDom.offsetTop + dragDom.clientHeight - 10) {
        dragDom.style.cursor = 's-resize'
      } else {
        dragDom.style.cursor = 'default'
        dragDom.onmousedown = null
      }
      dragDom.onmousedown = (e) => {
        const clientX = e.clientX
        const clientY = e.clientY
        const elW = dragDom.clientWidth
        const elH = dragDom.clientHeight
        const EloffsetLeft = dragDom.offsetLeft
        const EloffsetTop = dragDom.offsetTop
        // dragDom.style.userSelect = 'none'
        const ELscrollTop = el.scrollTop
        // 判断点击的位置是不是为头部
        if (clientX > EloffsetLeft && clientX < EloffsetLeft + elW && clientY > EloffsetTop && clientY < EloffsetTop + 100) {
          // 如果是头部在此就不做任何动作，以上有绑定dialogHeaderEl.onmousedown = moveDown;
        } else {
          document.onmousemove = function (e) {
            e.preventDefault() // 移动时禁用默认事件
            // 左侧鼠标拖拽位置
            if (clientX > EloffsetLeft && clientX < EloffsetLeft + 10) {
              // 往左拖拽
              if (clientX > e.clientX) {
                dragDom.style.width = elW + (clientX - e.clientX) * 2 + 'px'
              }
              // 往右拖拽
              if (clientX < e.clientX) {
                if (dragDom.clientWidth < minWidth) {
                } else {
                  dragDom.style.width = elW - (e.clientX - clientX) * 2 + 'px'
                }
              }
            }
            // 右侧鼠标拖拽位置
            if (clientX > EloffsetLeft + elW - 10 && clientX < EloffsetLeft + elW) {
              // 往左拖拽
              if (clientX > e.clientX) {
                if (dragDom.clientWidth < minWidth) {
                } else {
                  dragDom.style.width = elW - (clientX - e.clientX) * 2 + 'px'
                }
              }
              // 往右拖拽
              if (clientX < e.clientX) {
                dragDom.style.width = elW + (e.clientX - clientX) * 2 + 'px'
              }
            }
            // 底部鼠标拖拽位置
            if (ELscrollTop + clientY > EloffsetTop + elH - 20 && ELscrollTop + clientY < EloffsetTop + elH) {
              // 往上拖拽
              if (clientY > e.clientY) {
                if (dragDom.clientHeight < minHeight) {

                } else {
                  dragDom.style.height = elH - (clientY - e.clientY) * 2 + 'px'
                }
              }
              // 往下拖拽
              if (clientY < e.clientY) {
                dragDom.style.height = elH + (e.clientY - clientY) * 2 + 'px'
              }
            }
          }
          // 拉伸结束
          document.onmouseup = function () {
            document.onmousemove = null
            document.onmouseup = null
          }
        }
      }
    }
  }

})

import directives from '@/utils/directives'   (main.js)

  directives: {
    drag(el) {
      //div的拖拽
      el.onmousedown = function (e) {
        var x = e.pageX - el.offsetLeft;
        var y = e.pageY - el.offsetTop;
        document.onmousemove = function (e) {
          el.style.left = e.pageX - x + "px";
          el.style.top = e.pageY - y + "px";
        };
        // 鼠标抬起事件
        document.onmouseup = function () {
          document.onmousemove = document.onmouseup = null;
        };
      };
    },
  },