<template>
  <div class="detail-book">
    <div v-if="list.length > 0">
      <div
        class="book-page"
        v-for="(node, i) in list"
        :key="i"
        :class="{ active: i === activePage, flipped: i < activePage }"
      >
        <div
          class="article-title"
          @click="handlePageChange(i, true)"
          v-if="node.imagesVo[0]"
        >
          <div
            class="img"
            :style="`background-image: url('${
              node.imagesVo[0] && node.imagesVo[0].url
            }')`"
          ></div>
          <p>
            <span class="title">{{ node.title }}</span>
            <span class="seq">{{ node.unit }}</span>
          </p>
        </div>
        <div
          class="article-big-title"
          v-else
          @click="handlePageChange(i, true)"
        >
          <p>
            <span class="seq">{{ node.unit }}</span>
            <span class="title">{{ node.title }}</span>
          </p>
        </div>
        <div class="book-cover" v-if="i === 0" @click="handlePageChange(i)">
          <div class="img" :style="`background-image: url('${img}')`"></div>
          <p>
            <span>{{ title }}</span>
          </p>
        </div>
        <div class="article-content" v-else @click="handlePageChange(i)">
          <div class="content-detail" v-html="list[i - 1].intro"></div>
        </div>
      </div>
      <div class="book-page">
        <div class="article-content">
          <div
            class="content-detail"
            v-html="list[list.length - 1].intro"
          ></div>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
export default {
  props: {
    data: {
      type: Array,
      default: () => [],
    },
    title: {
      type: String,
      default: "",
    },
    img: {
      type: String,
      default: "",
    },
  },
  data() {
    return {
      activePage: 0,
    };
  },
  computed: {
    list() {
      let arr = this.data;

      return this.transformTree2List(arr);
    },
  },
  methods: {
    handlePageChange(index, flag) {
      if (flag) {
        this.activePage = index;
      } else {
        this.activePage = index + 1;
      }
    },
    transformTree2List(arr) {
      let list = [];
      let loopTree = (data) => {
        data.forEach((n) => {
          list.push(n);
          if (n.children && n.children.length > 0) {
            loopTree(n.children);
          }
        });
      };

      loopTree(arr);
      return list;
    },
  },
};
</script>

<style lang="scss" scoped>
.detail-book {
  position: relative;
  width: 100%;
  height: 100%;
  min-height: 800px;
  perspective: 1000px;
  > div {
    // position: absolute;
    position: absolute;
    // width: 800px;
    width: 48%;
    height: 600px;
    top: 50%;
    left: 50%;
    transform: translate(0%, -50%);
    transform-style: preserve-3d;
    /* &:first-child,
    &:last-child {
      box-shadow: 0px -5px 0 2px #8f712fdb;
    } */
  }
  .book-page {
    position: absolute;
    // width: 800px;
    width: 100%;
    height: 100%;
    transition: all 1.5s;
    transform-style: preserve-3d;
    transform-origin: 0 0;
    border-left: 2px solid #8f712fdb;
    box-shadow: 6px 6px 0 2px #8f712fdb;
    &.active {
      z-index: 1;
    }
    &.flipped {
      //   z-index: 1;
      transform: rotateY(-180deg);
    }
    > div {
      position: absolute;
      width: 100%;
      height: 100%;
      box-sizing: border-box;
      backface-visibility: hidden;
      background-color: #bfa277;
    }
    .book-cover {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 30px;
      width: 100%;
      height: 100%;

      > .img {
        width: 600px;
        height: 400px;
        background-size: cover;
        background-repeat: no-repeat;
        background-position: 50% 50%;
        margin: 50px auto;
      }
      > p {
        display: flex;
        > span {
          display: block;
          text-align: center;
          font-size: 22px;
          font-weight: 600;
          font-family: "楷体";
          writing-mode: tb-rl;
          &.title {
            color: #850e0e;
            font-size: 30px;
          }
          &.seq {
            padding-bottom: 100px;
            margin-left: 20px;
          }
        }
      }
    }
    .article-title {
      @extend .book-cover;
      transform: rotateY(180deg);
      > .img {
        border-radius: 10px;
      }
    }
    .article-big-title {
      display: flex;
      justify-content: center;
      align-items: center;
      transform: rotateY(180deg);
      > p {
        font-size: 36px;
        text-align: center;
        font-family: "华文行楷";
        > span {
          display: block;
          margin: 20px;
          &.title {
            color: #fff2b3;
          }
        }
      }
    }
    .article-content {
      width: 100%;
      height: 100%;
      padding: 50px 100px;
      line-height: 1.8;
      color: #333;
      font-weight: 600;
      font-family: "仿宋";
      text-indent: 32px;
      overflow: auto;
    }
  }
}
</style>
