export default {
    bind(el, binding, vnode, oldVnode) {
        const resizeEvent = new CustomEvent('drag-resize', {
            detail: '尺寸变化',
            bubbles: false
        })
        // 初始化不最大化
        el.fullscreen = false
        // 弹框可拉伸最小宽高
        const minWidth = 1100
        const minHeight = 570
        // 当前宽高
        let nowWidth = minWidth
        // eslint-disable-next-line no-unused-vars
        let nowHight = minHeight
        // 当前顶部高度
        let nowMarginTop = 0
        // 获取弹框头部（这部分可双击全屏）
        const dialogHeaderEl = el.querySelector('.el-dialog__header')
        let hasSetBodyHight = false
        // 弹窗
        const dragDom = el.querySelector('.el-dialog')
        el.style.overflow = 'initial'
        dragDom.className += ' el-drag-dialog'

        // 给弹窗加上overflow auto；不然缩小时框内的标签可能超出dialog；
        dragDom.style.overflow = 'auto'
        // 清除选择头部文字效果
        // eslint-disable-next-line no-new-func
        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)

        // 头部插入最大化最小化元素
        const maxMin = document.createElement('button')
        maxMin.className += ' el-dialog__headerbtn el-dialog__minmax'
        maxMin.style.right = '40px'
        maxMin.style.color = '#ffffff'
        maxMin.title = el.fullscreen ? '还原' : '最大化'
        maxMin.innerHTML = '<i class=' + (el.fullscreen ? '"el-icon-crop"' : '"el-icon-full-screen"') + ' onMouseOver="this.style.color=\'#409EFF\'" onMouseOut="this.style.color=\'inherit\'"></i>'
        dialogHeaderEl.insertBefore(maxMin, dialogHeaderEl.childNodes[1])
        const moveDown = (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) {
                // 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 (e) {
                document.onmousemove = null
                document.onmouseup = null
            }
        }
        dialogHeaderEl.onmousedown = moveDown
        let bodyHeight = 'auto'

        function setMaxMin() {
            if (el.fullscreen) {
                let i = maxMin.querySelector('.el-icon-crop');
                i.classList.remove('el-icon-crop');
                i.classList.add('el-icon-full-screen');
                maxMin.innerHTML = '<i class="el-icon-full-screen"></i>';
                maxMin.title = '最大化';
                dragDom.style.height = nowHight + 'px';
                dragDom.style.width = nowWidth + 'px';
                dragDom.style.marginTop = window.innerHeight * 0.07 + 'px';
                el.fullscreen = false;
                dialogHeaderEl.style.cursor = 'move';
                dialogHeaderEl.onmousedown = moveDown;
                // dragDom.querySelector('.el-dialog__body').style.height = bodyHeight;
                hasSetBodyHight = false;
            } else {
                const i = maxMin.querySelector('.el-icon-full-screen')
                i.classList.remove('el-icon-full-screen')
                i.classList.add('el-icon-crop')
                maxMin.title = '还原'
                bodyHeight = dragDom.querySelector('.el-dialog__body').offsetHeight + 'px'
                nowHight = dragDom.clientHeight
                nowWidth = dragDom.clientWidth
                nowMarginTop = dragDom.style.marginTop
                dragDom.style.left = 0
                dragDom.style.top = 0
                dragDom.style.height = window.innerHeight + 'px'
                dragDom.style.width = '100VW'
                dragDom.style.marginTop = 0
                el.fullscreen = true
                dialogHeaderEl.style.cursor = 'initial'
                dialogHeaderEl.onmousedown = null
                if (!hasSetBodyHight) {
                    const footerHeight = dragDom.querySelector('.el-dialog__footer') && dragDom.querySelector('.el-dialog__footer').offsetHeight
                    // dragDom.querySelector('.el-dialog__body').style.height =
                    //     'calc(90% - ' + (dialogHeaderEl.offsetHeight + footerHeight) + 'px)'
                    dragDom.querySelector('.el-dialog__body').style.height =
                        'calc(90% - ' + (dialogHeaderEl.offsetHeight + footerHeight) + 'px)'
                    /*          dragDom.querySelector('.el-dialog__body').style.height =
                                window.innerHeight*0.9
                                 - (dialogHeaderEl.offsetHeight + footerHeight) + 'px'*/
                    hasSetBodyHight = true
                }
            }
            el.dispatchEvent(resizeEvent)
        }

        // 点击放大缩小效果
        maxMin.onclick = setMaxMin
        // 双击头部效果
        dialogHeaderEl.ondblclick = setMaxMin
        // 拉伸
        const resizeEl = document.createElement('div')
        dragDom.appendChild(resizeEl)
        // 在弹窗右下角加上一个10-10px的控制块
        resizeEl.style.cursor = 'se-resize'
        resizeEl.style.position = 'absolute'
        resizeEl.style.height = '10px'
        resizeEl.style.width = '10px'
        resizeEl.style.right = '0px'
        resizeEl.style.bottom = '0px'
        resizeEl.style.zIndex = '99';
        // 鼠标拉伸弹窗
        resizeEl.onmousedown = (e) => {
            // 记录初始x位置
            const clientX = e.clientX
            // 鼠标按下，计算当前元素距离可视区的距离
            const disX = e.clientX - resizeEl.offsetLeft
            const disY = e.clientY - resizeEl.offsetTop
            document.onmousemove = function (e) {
                e.preventDefault() // 移动时禁用默认事件
                // 通过事件委托，计算移动的距离
                const x = e.clientX - disX + (e.clientX - clientX)// 这里 由于elementUI的dialog控制居中的，所以水平拉伸效果是双倍
                const y = e.clientY - disY
                // 比较是否小于最小宽高
                dragDom.style.width = x > minWidth ? `${x}px` : minWidth + 'px'
                dragDom.style.height = y > minHeight ? `${y}px` : minHeight + 'px'
                if (!hasSetBodyHight) {
                    const footerHeight = dragDom.querySelector('.el-dialog__footer') && dragDom.querySelector('.el-dialog__footer').offsetHeight
                    dragDom.querySelector('.el-dialog__body').style.height = 'calc(90% - ' + (dialogHeaderEl.offsetHeight + footerHeight) + 'px)'
                    hasSetBodyHight = true
                }
            }
            // 拉伸结束
            document.onmouseup = function (e) {
                document.onmousemove = null
                document.onmouseup = null
                el.dispatchEvent(resizeEvent)
            }
        }
    }
}