import Vue from 'vue';
/**
 * 插入loading
 */
const insertDom = (el) => {
  let dom = `<div class="el-loading-mask">
        <div class="el-loading-spinner">
          <svg viewBox="25 25 50 50" class="circular">
            <circle cx="50" cy="50" r="20" fill="none" class="path"> </circle>
          </svg>
          <p class="el-loading-text">拼命加載中...</p>
        </div>
      </div>`;

  //el添加相對定位
  el.classList.add('el-loading-parent--relative');

  // 插入到被綁定的元素內部
  el.insertAdjacentHTML('afterbegin', dom);
};

/**
 * 移除loading
 */
const removeDom = (el) => {
  const ds = el.getElementsByClassName('el-loading-mask')[0];
  if (ds) {
    el.removeChild(ds);
    el.classList.remove('el-loading-parent--relative');
  }
};

// 更新是否顯示
const toggleLoading = (el, binding) => {
  if (binding.value) {
    insertDom(el);
  } else {
    removeDom(el);
  }
};

Vue.directive('loading', {
  bind: function (el, binding, vnode) {
    toggleLoading(el, binding);
  },
  //所在組件的 VNode 更新時調用--比較更新前后的值
  update: function (el, binding) {
    if (binding.oldValue !== binding.value) {
      toggleLoading(el, binding);
    }
  }
});

/deep/ .el-loading-parent--relative {
  position: relative !important;
}

/deep/ .el-loading-mask {
  position: absolute;
  z-index: 2000;
  background-color: rgba(0, 0, 0, 0.8);
  margin: 0;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  transition: opacity 0.3s;

  .el-loading-spinner {
    top: 50%;
    margin-top: -21px;
    width: 100%;
    text-align: center;
    position: absolute;
  }

  .el-loading-spinner .el-loading-text {
    color: #409eff;
    margin: 3px 0;
    font-size: 14px;
  }

  .el-loading-spinner .circular {
    height: 42px;
    width: 42px;
    animation: loading-rotate 2s linear infinite;
  }

  .el-loading-spinner .path {
    animation: loading-dash 1.5s ease-in-out infinite;
    stroke-dasharray: 90, 150;
    stroke-dashoffset: 0;
    stroke-width: 2;
    stroke: #409eff;
    stroke-linecap: round;
  }

  .el-loading-spinner i {
    color: #409eff;
  }

  .el-loading-fade-enter,
  .el-loading-fade-leave-active {
    opacity: 0;
  }

  @keyframes loading-rotate {
    to {
      transform: rotate(1turn);
    }
  }

  @keyframes loading-dash {
    0% {
      stroke-dasharray: 1, 200;
      stroke-dashoffset: 0;
    }

    50% {
      stroke-dasharray: 90, 150;
      stroke-dashoffset: -40px;
    }

    to {
      stroke-dasharray: 90, 150;
      stroke-dashoffset: -120px;
    }
  }
}

@import '/static/css/loading.scss';

// 使用v-loading
import Loading from '@/utils/loading.js'
Vue.use(Loading)

<view class="details-video" v-loading="loading"></view>