import Vue from "vue";

// 自定义元素实现弹框拖拽[重点]
Vue.directive("draw", {
  inserted: function (el, binding, vNode) {
    el.setAttribute("style", "position: fixed; z-index: 9999");
  },

  bind: function (el, bindding, vNode) {
    el.setAttribute("draggable", true);

    let left, top, width, height;

    el._dragstart = function (event) {
      event.stopPropagation();

      left = event.clientX - el.offsetLeft;

      top = event.clientY - el.offsetTop;

      width = el.offsetWidth;

      height = el.offsetHeight;
    };

    el._checkPosition = function () {
      // 防止被拖出边界

      const width = el.offsetWidth;

      const height = el.offsetHeight;

      let left = Math.min(el.offsetLeft, document.body.clientWidth - width);

      left = Math.max(0, left);

      let top = Math.min(el.offsetTop, document.body.clientHeight - height);

      top = Math.max(0, top);

      el.style.left = left + "px";

      el.style.top = top + "px";

      el.style.width = width + "px";

      el.style.height = height + "px";
    };

    el._dragEnd = function (event) {
      event.stopPropagation();

      left = event.clientX - left;

      top = event.clientY - top;

      el.style.left = left + "px";

      el.style.top = top + "px";

      el.style.width = width + "px";

      el.style.height = height + "px";

      el._checkPosition();
    };

    el._documentAllowDraop = function (event) {
      event.preventDefault();
    };

    document.body.addEventListener("dragover", el._documentAllowDraop);

    el.addEventListener("dragstart", el._dragstart);

    el.addEventListener("dragend", el._dragEnd);

    window.addEventListener("resize", el._checkPosition);
  },

  unbind: function (el, bindding, vNode) {
    document.body.removeEventListener("dragover", el._documentAllowDraop);

    el.removeEventListener("dragstart", el._dragstart);

    el.removeEventListener("dragend", el._dragEnd);

    window.removeEventListener("resize", el._checkPosition);

    delete el._documentAllowDraop;

    delete el._dragstart;

    delete el._dragEnd;

    delete el._checkPosition;
  },
});

// v-dialogDrag: 弹窗拖拽

Vue.directive("dialogDrag", {
  bind(el, binding, vnode, oldVnode) {
    const dialogHeaderEl = el.querySelector(".el-dialog__header");

    const dragDom = el.querySelector(".el-dialog");

    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);

    dialogHeaderEl.onmousedown = (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;
      };
    };
  },
});

// v-dialogDragWidth: 弹窗宽度拖大 拖小

Vue.directive("dialogDragWidth", {
  bind(el, binding, vnode, oldVnode) {
    const dragDom = binding.value.$el.querySelector(".el-dialog");

    el.onmousedown = (e) => {
      // 鼠标按下，计算当前元素距离可视区的距离

      const disX = e.clientX - el.offsetLeft;

      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 l = e.clientX - disX;

        dragDom.style.width = `${l}px`;
      };

      document.onmouseup = function (e) {
        document.onmousemove = null;

        document.onmouseup = null;
      };
    };
  },
});