<template>
  <transition v-if="loading" name="fade">
    <div class="loading-mask">
      <div class="loading-spinner">
        <svg viewBox="25 25 50 50" class="circular">
          <circle cx="50" cy="50" r="20" fill="none" class="path" />
        </svg>
        <p class="loading-text">
          <slot>加载中...</slot>
        </p>
      </div>
    </div>
  </transition>
</template>

<script>
export default {
  props: {
    loading: {
      type: Boolean,
      default: false
    }
  }
}
</script>

<style lang="scss">
.loading-mask {
  position: absolute;
  z-index: 10000;
  background-color: hsla(0,0%,100%,.9);
  margin: 0;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  transition: opacity .3s;
  .loading-spinner {
    top: 50%;
    margin-top: -21px;
    width: 100%;
    text-align: center;
    position: absolute;
    .circular {
      display: inline-block;
      width: 42px;
      height: 42px;
      animation: loading-rotate 2s linear infinite;
    }
    .path {
      animation: loading-dash 1.5s ease-in-out infinite;
      stroke-dasharray: 90,150;
      stroke-dashoffset: 0;
      stroke-width: 2;
      stroke: #20a0ff;
      stroke-linecap: round
    }
    .loading-text {
      color: #20a0ff;
      margin: 10px 0;
      font-size: 14px;
    }
  }
}
@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
  }
}
</style>
