<template>
  <div v-if="!item.hidden">
    <template
        v-if="hasOneShowingChild(item.children,item) && (!onlyOneChild.children||onlyOneChild.noShowingChildren)&&!item.alwaysShow">
      <router-link v-if="onlyOneChild.meta" :to="resolvePath(onlyOneChild.path)">
        <el-menu-item :index="resolvePath(onlyOneChild.path)" :class="{'submenu-title-noDropdown':!isNest}">
          <el-icon class="sub-el-icon">
            <i :class="[ICON_PREFIX,onlyOneChild.meta.icon]"></i>
          </el-icon>
          <template #title> {{ onlyOneChild.meta.title }} </template>
        </el-menu-item>
      </router-link>
    </template>

    <el-sub-menu v-else ref="subMenu" :index="resolvePath(item.path)" popper-append-to-body>
      <template #title >
        <el-icon class="sub-el-icon">
          <i :class="[ICON_PREFIX,item.meta.icon]"></i>
        </el-icon>
        <span v-if="item.meta"> {{ item.meta.title }} </span>
      </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-sub-menu>
  </div>
</template>

<script>
import path from "path";
import {isExternal} from "@/utils/validate";
import { Camera } from '@element-plus/icons'
import {ICON_PREFIX} from "@/setting";

export default {
  name: "SidebarItem",
  components : {
    Camera
  },
  props: {
    // route object
    item: {
      type: Object,
      required: true
    },
    isNest: {
      type: Boolean,
      default: false
    },
    basePath: {
      type: String,
      default: ''
    }
  },
  data() {
    return {
      ICON_PREFIX,
      onlyOneChild: null
    }
  },
  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 scoped>

</style>