<template>
  <div class="Breadcrumb">
    <i
      class="el-icon-d-arrow-left fl"
      :class="{ cor: isShow }"
      @click="back_arrow"
    ></i>
    <el-breadcrumb class="app-breadcrumb" separator="/">
      <transition-group name="breadcrumb">
        <el-breadcrumb-item v-for="(item, index) in levelList" :key="item.path">
          <span
            v-if="item.redirect === 'noRedirect' || index > 0"
            class="no-redirect"
            >{{ item.meta.title }}</span
          >
          <a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
        </el-breadcrumb-item>
      </transition-group>
    </el-breadcrumb>
  </div>
</template>

<script>
import pathToRegexp from "path-to-regexp";

export default {
  name: "Breadcrumb",
  data() {
    return {
      levelList: null,
      isShow: false,
      backOtions: null,
      backUrl: "",
    };
  },
  watch: {
    $route(route) {
      // if you go to the redirect page, do not update the breadcrumbs
      if (route.path.startsWith("/redirect/")) {
        this.isShow = false;
        return;
      }
      this.getBreadcrumb();
    },
  },
  created() {
    this.getBreadcrumb();
  },
  methods: {
    getBreadcrumb() {
      // only show routes with meta.title
      let matched = this.$route.matched.filter(
        (item) => item.meta && item.meta.title
      );
      const first = matched[0];

      if (!this.isDashboard(first)) {
        matched = [
          { path: "/welcome/dashboard", meta: { title: "首页" } },
        ].concat(matched);
      }

      this.levelList = matched.filter(
        (item) => item.meta && item.meta.title && item.meta.breadcrumb !== false
      );
      const { preModel } = this.$route.query;
      if (preModel) {
        let model = JSON.parse(preModel);
        this.isShow = true;
        const { options, router } = model;
        this.backOtions = options;
        this.backUrl = router;
      } else {
        this.isShow = false;
      }
    },
    isDashboard(route) {
      const name = route && route.name;
      if (!name) {
        return false;
      }
      return (
        name.trim().toLocaleLowerCase() === "Dashboard".toLocaleLowerCase()
      );
    },
    pathCompile(path) {
      const { params } = this.$route;
      var toPath = pathToRegexp.compile(path);
      return toPath(params);
    },
    back_arrow() {
      if (!this.isShow) {
        return;
      }
      window.vm.$router.push({
        path: this.backUrl,
        query: {
          back: JSON.stringify(this.backOtions),
        },
      });
    },
    handleLink(item) {
      const { redirect, path } = item;
      if (redirect) {
        window.vm.$router.push(redirect);
        return;
      }
      window.vm.$router.push(this.pathCompile(path));
    },
  },
};
</script>

<style lang="scss" scoped>
.Breadcrumb {
  .el-icon-d-arrow-left {
    display: inline-block;
    font-size: 14px;
    line-height: 50px;
    margin: 0 8px 0 1px;
    color: transparent;
    &.cor {
      color: #000;
      &:hover {
        cursor: pointer;
      }
    }
  }
  .app-breadcrumb.el-breadcrumb {
    display: inline-block;
    font-size: 14px;
    line-height: 50px;

    .no-redirect {
      color: #97a8be;
      cursor: text;
    }
  }
}
</style>
