<template>
  <div v-if="!item.hidden" class="menu-wrapper">
    <template
      v-if="
        hasOneShowingChild(item.children, item) &&
        (!onlyOneChild.children || onlyOneChild.noShowingChildren) &&
        !item.alwaysShow
      "
    >
      <app-link
        v-if="onlyOneChild.meta"
        :to="
          resolvePath(
            onlyOneChild.path +
              (onlyOneChild.meta.querys ? '?' + onlyOneChild.meta.querys : '')
          )
        "
      >
        <el-menu-item
          :index="resolvePath(onlyOneChild.path)"
          :class="{ 'submenu-title-noDropdown': !isNest }"
        >
          <icon-item
            :icon="onlyOneChild.meta.icon || (item.meta && item.meta.icon)"
            :title="onlyOneChild.meta.title"
          />
        </el-menu-item>
      </app-link>
    </template>

    <template v-else>
      <el-submenu id="subid" ref="subMenu" :index="resolvePath(item.path)">
        <template slot="title">
          <icon-item
            v-if="item.meta"
            :icon="item.meta && item.meta.icon"
            :title="item.meta.title"
          />
        </template>
        <sidebar-item
          v-for="child in item.children"
          :key="child.path"
          :is-nest="true"
          :item="child"
          :base-path="resolvePath(child.path)"
          class="nest-menu"
        />
      </el-submenu>
    </template>
  </div>
</template>

<script>
import path from "path";
import { isExternal } from "@/utils/validate";
import IconItem from "./Item.vue";
import AppLink from "./Link";

export default {
  name: "SidebarItem",
  components: { IconItem, AppLink },
  props: {
    // route object
    item: {
      type: Object,
      required: true,
    },
    isNest: {
      type: Boolean,
      default: false,
    },
    basePath: {
      type: String,
      default: "",
    },
  },
  data() {
    // To fix https://github.com/PanJiaChen/vue-admin-template/issues/237
    // TODO: refactor with render function
    this.onlyOneChild = null;
    return {};
  },
  mounted() {},
  methods: {
    hasOneShowingChild(children = [], parent) {
      const showingChildren = children.filter((item) => {
        if (item.hidden) {
          return false;
        } else {
          // Temp set(will be used if only has one showing child)
          this.onlyOneChild = item;
          return true;
        }
      });

      // When there is only one child router, the child router is displayed by default
      if (showingChildren.length === 1) {
        return true;
      }

      // Show parent if there are no child router to display
      if (showingChildren.length === 0) {
        this.onlyOneChild = { ...parent, path: "", noShowingChildren: true };
        return true;
      }

      return false;
    },
    resolvePath(routePath) {
      if (isExternal(routePath)) {
        return routePath;
      }
      if (isExternal(this.basePath)) {
        return this.basePath;
      }
      return path.resolve(this.basePath, routePath);
    },
  },
};
</script>

<style lang="scss" scoped>
.menu-wrapper {
  &:focus {
    outline: none;
  }
  a {
    text-decoration: none;
    color: inherit;
    display: inline-block;
    width: 100%;
  }
}
.el-menu--collapse .el-menu .el-submenu,
.el-menu--popup {
  min-width: 120px !important;
}
.el-menu .el-menu--popup .el-menu--popup-bottom-start ::v-deep {
  width: 1020px;
}
</style>