<template>
  <HomePanel title="热门品牌" sub-title="国际经典 品质保证">
    <template v-slot:right>
      <a @click="toggle(-1)" :class="{disabled:index===0}" href="javascript:" class="iconfont icon-angle-left prev"></a>
      <a @click="toggle(1)" :class="{disabled:index===1}" href="javascript:" class="iconfont icon-angle-right next"></a>
    </template>
    <div ref="target" class="box">
      <Transition name="fade">
        <ul v-if="brands.length" class="list" :style="{transform:`translateX(${-index*1240}px)`}">
          <li v-for="item in brands" :key="item.id">
            <RouterLink to="/">
              <img :src="item.picture" alt="">
            </RouterLink>
          </li>
        </ul>
        <div v-else class="skeleton">
          <XtxSkeleton class="item" v-for="i in 5" :key="i" animated bg="#e4e4e4" width="240px" height="305px"/>
        </div>
      </Transition>
    </div>
  </HomePanel>
</template>

<script>
import { ref } from 'vue'
import HomePanel from './home-panel'
import { findBrand } from '@/api/home'
import { useLazyData } from '@/hooks'
import XtxSkeleton from '@/components/library/xtx-skeleton.vue'

export default {
  name: 'HomeBrand',
  components: {
    HomePanel,
    XtxSkeleton
  },
  setup () {
    // 获取数据
    const brands = ref([])
    findBrand(10).then(data => {
      brands.value = data.result
    })
    // 注意：useLazyData需要的是API函数，如果遇到要传参的情况，自己写函数再函数中调用API

    const {
      target,
      result
    } = useLazyData(() => findBrand(10))

    // 切换效果，前提只有 0 1 两页
    const index = ref(0)
    // 1. 点击上一页
    // 2. 点击下一页
    const toggle = (step) => {
      const newIndex = index.value + step
      if (newIndex < 0 || newIndex > 1) return
      index.value = newIndex
    }
    return {
      brands: result,
      toggle,
      index,
      target
    }
  }
}
</script>

<style scoped lang='less'>
.home-panel {
  background: #f5f5f5
}

.iconfont {
  width: 20px;
  height: 20px;
  background: #ccc;
  color: #fff;
  display: inline-block;
  text-align: center;
  margin-left: 5px;
  background: #27BA9B;

  &::before {
    font-size: 12px;
    position: relative;
    top: -2px
  }

  &.disabled {
    background: #ccc;
    cursor: not-allowed;
  }
}

.box {
  display: flex;
  width: 100%;
  height: 345px;
  overflow: hidden;
  padding-bottom: 40px;

  .list {
    width: 200%;
    display: flex;
    transition: all 1s;

    li {
      margin-right: 10px;
      width: 240px;

      &:nth-child(5n) {
        margin-right: 0;
      }

      img {
        width: 240px;
        height: 305px;
      }
    }
  }

  .skeleton {
    width: 100%;
    display: flex;

    .item {
      margin-right: 10px;

      &:nth-child(5n) {
        margin-right: 0;
      }
    }
  }
}
</style>
