<template>
    <div v-if="!item.hidden" >
      <!-- 最后一级菜单 -->
      <el-menu-item
        v-if="isHaveOneChild(item.children,item) && (!onlyOneChild.children||onlyOneChild.noShowingChildren)"
        :index="resolvePath(onlyOneChild.path)"
      >
        <IconFont :icon="onlyOneChild.meta.icon||(item.meta&&item.meta.icon)" class="menu-drawer-icon" size="18px"/>
        <span slot="title">{{onlyOneChild.meta.title}} </span>
      </el-menu-item>

      <!-- 此菜单下还有子菜单 -->
      <el-submenu
        v-else
        :popper-append-to-body="false"
        :index="resolvePath(item.path)"
      >
        <template slot="title">
           <IconFont :icon="item.meta && item.meta.icon" class="menu-drawer-icon" size="18px"/>
          <span>{{item.meta.title}}</span>
        </template>
        <!-- 递归 -->
        <sidebar-item
          v-for="(child,number) in item.children"
          :key="number"
          :item="child"
          :basePath="resolvePath(child.path)"
        />
      </el-submenu>
    </div>
</template>

<script>
import path from 'path'
export default {
  name: "SidebarItem", //使用场景:允许组件模板递归地调用自身
  props: {
    "item":{
      type: Object,
      required: true
    },
    "basePath":{
      type: String,
      default: ''
    }
  },
  data() {
    this.onlyOneChild = null
    return {
      // onlyOneChild: null
    };
  },
  methods: {
    isHaveOneChild(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){
        // console.log('studyGit-basePath',this.basePath)
        // console.log('studyGit-routePath',routePath)
        // console.log('studyGit-后的路径',path.resolve(this.basePath, routePath))
         return path.resolve(this.basePath, routePath);
     }
  }
};
</script>