<template>
  <el-menu
    :default-active="activeMenu"
    mode="horizontal"
    @select="handleSelect"
    class="topmenu-container"
  >
    <template v-for="(item, index) in topMenus">
      <el-menu-item :style="{'--theme': theme}" :index="item.path" :key="index" v-if="index < visibleNumber"
        ><svg-icon :icon-class="item.meta.icon" />
        {{ item.meta.title }}</el-menu-item
      >
    </template>

    <el-submenu :style="{'--theme': theme}" index="more" v-if="topMenus.length > visibleNumber">
      <template slot="title">更多菜单</template>
      <template v-for="(item, index) in topMenus">
        <el-menu-item
          :index="item.path"
          :key="index"
          v-if="index >= visibleNumber"
          ><svg-icon :icon-class="item.meta.icon" />
          {{ item.meta.title }}</el-menu-item
        >
      </template>
    </el-submenu>
  </el-menu>
</template>

<script>
import { constantRoutes } from '@/router'

export default {
  data() {
    return {
      visibleNumber: 12,
      isFrist: false,
      currentIndex: undefined
    }
  },
  computed: {
    theme() {
      return this.$store.state.settings.theme
    },
    topMenus() {
      const topMenus = []
      this.routers.map((menu) => {
        if (menu.hidden !== true) {
          if (menu.path === '/') {
            topMenus.push(menu.children[0])
          } else {
            topMenus.push(menu)
          }
        }
      })
      return topMenus
    },
    routers() {
      return this.$store.state.permission.topbarRouters
    },
    childrenMenus() {
      var childrenMenus = []
      this.routers.map((router) => {
        for (var item in router.children) {
          if (router.children[item].parentPath === undefined) {
            if (router.path === '/') {
              router.children[item].path = '/redirect/' + router.children[item].path
            } else {
              if (!this.ishttp(router.children[item].path)) {
                router.children[item].path = router.path + '/' + router.children[item].path
              }
            }
            router.children[item].parentPath = router.path
          }
          childrenMenus.push(router.children[item])
        }
      })
      return constantRoutes.concat(childrenMenus)
    },
    activeMenu() {
      const path = this.$route.path
      let activePath = this.defaultRouter()
      if (path.lastIndexOf('/') > 0) {
        const tmpPath = path.substring(1, path.length)
        activePath = '/' + tmpPath.substring(0, tmpPath.indexOf('/'))
      } else if (path === '/index' || path === '') {
        if (!this.isFrist) {
          this.isFrist = true
        } else {
          activePath = 'index'
        }
      }
      var routes = this.activeRoutes(activePath)
      if (routes.length === 0) {
        activePath = this.currentIndex || this.defaultRouter()
        this.activeRoutes(activePath)
      }
      return activePath
    }
  },
  beforeMount() {
    window.addEventListener('resize', this.setVisibleNumber)
  },
  beforeDestroy() {
    window.removeEventListener('resize', this.setVisibleNumber)
  },
  mounted() {
    this.setVisibleNumber()
  },
  methods: {
    setVisibleNumber() {
      const width = document.body.getBoundingClientRect().width / 3
      this.visibleNumber = parseInt(width / 85)
    },
    defaultRouter() {
      let router
      Object.keys(this.routers).some((key) => {
        if (!this.routers[key].hidden) {
          router = this.routers[key].path
          return true
        }
      })
      return router
    },
    handleSelect(key) {
      this.currentIndex = key
      if (this.ishttp(key)) {
        window.open(key, '_blank')
      } else if (key.indexOf('/redirect') !== -1) {
        this.$router.push({ path: key.replace('/redirect', '') })
      } else {
        this.activeRoutes(key)
      }
    },
    activeRoutes(key) {
      var routes = []
      if (this.childrenMenus && this.childrenMenus.length > 0) {
        this.childrenMenus.map((item) => {
          if (key === item.parentPath || (key === 'index' && item.path === '')) {
            routes.push(item)
          }
        })
      }
      if (routes.length > 0) {
        this.$store.commit('SET_SIDEBAR_ROUTERS', routes)
      }
      return routes
    },
    ishttp(url) {
      return url.indexOf('http://') !== -1 || url.indexOf('https://') !== -1
    }
  }
}
</script>

<style lang="scss">
@import '~@/assets/styles/admin-menu.scss';

.topmenu-container.el-menu--horizontal {
  border-bottom: none !important;

  & > .el-menu-item {
    float: left;
    height: $admin-top-height !important;
    line-height: $admin-top-height !important;
    color: $admin-top-text !important;
    font-size: 14px;
    font-weight: 500;
    padding: 0 18px !important;
    margin: 0 !important;
    border-bottom: 2px solid transparent !important;
    background: transparent !important;

    &:hover {
      color: $admin-top-active !important;
      background: transparent !important;
    }

    &.is-active {
      color: $admin-top-active !important;
      border-bottom: 2px solid $admin-top-active !important;
      background: transparent !important;
    }

    .svg-icon {
      margin-right: 6px;
      font-size: 16px;
    }
  }

  & > .el-submenu {
    .el-submenu__title {
      height: $admin-top-height !important;
      line-height: $admin-top-height !important;
      color: $admin-top-text !important;
      font-size: 14px;
      font-weight: 500;
      padding: 0 18px !important;
      margin: 0 !important;
      border-bottom: 2px solid transparent !important;
      background: transparent !important;

      &:hover {
        color: $admin-top-active !important;
        background: transparent !important;
      }

      .svg-icon {
        margin-right: 6px;
        font-size: 16px;
      }
    }

    &.is-active .el-submenu__title {
      color: $admin-top-active !important;
      border-bottom: 2px solid $admin-top-active !important;
    }
  }
}
</style>
