<template>
  <div class="avatar-list-wrap">
    <ul v-if="avatarList" class="avatar-list">
        <li v-for="(item, index) in avatarList" :key="index" :style="item.style">
          <ImageFormat :src="item.src"></ImageFormat>
        </li>
        <li v-if="hasMore">
          <img src="data:image/png;base64,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">
        </li>
    </ul>
  </div>
</template>

<script>
  export default {
    name: 'AvatarGroup',
    props: {
      avatars: Array,
      option: {
        type: Object,
        default() {
          return {
            srcKey: 'src',
            maxDisplayNum: 0
          };
        }
      }
    },
    data() {
      return {
        hasMore: false
      }
    },
    computed: {
      avatarList() {
        let list = [];
        let length = this.avatars.length;

        if (this.option.maxDisplayNum > 0 && this.avatars.length > this.option.maxDisplayNum) {
          length = this.option.maxDisplayNum;
          this.hasMore = true;
        }

        for (let i = 0; i < length; i++) {
          let avt = this.avatars[i];
          let src = avt;

          if (this.option.srcKey && typeof avt !== 'string') {
            src = avt[this.option.srcKey] || '';
          }

          list.push({
            src: src,
            style: `z-index: ${length - i};`
          });
        }

        return list;
      }
    }
  };
</script>

<style type="css">
  .avatar-list-wrap {
    display: inline-block;
  }
  .avatar-list {
    display: flex;

    li {
      width: 60px;
      height: 60px;
      border: 1px solid #fff;
      border-radius: 50%;
      overflow: hidden;
      margin-left: -18px;
      position: relative;

      &:first-child {
        margin-left: 0;
      }

      img {
        display: block;
        width: 100%;
        height: 100%;
      }
    }
  }
</style>