import Vue from 'vue'
  import Router from 'vue-router'
  import Login from '@/views/Login'
  import Home from '@/views/Home'
  import NotFound from '@/views/404'
  import api from '@/http/api'
  import store from '@/store'
  
  Vue.use(Router)
  
  const router = new Router({
    routes: [
      {
        path: '/',
        name: '首页',
        component: Home,
        children: []
      },
      {
        path: '/login',
        name: '登录',
        component: Login
      },
      {
        path: '/404',
        name: 'notFound',
        component: NotFound
      }
    ]
  })
  
  router.beforeEach((to, from, next) => {
    // 登录界面登录成功之后，会把用户信息保存在会话
    // 存在时间为会话生命周期，页面关闭即失效。
    let userName = sessionStorage.getItem('user')
    if (to.path === '/login') {
      // 如果是访问登录界面，如果用户会话信息存在，代表已登录过，跳转到主页
      if(userName) {
        next({ path: '/' })
      } else {
        next()
      }
    } else {
      if (!userName) {
        // 如果访问非登录界面，且户会话信息不存在，代表未登录，则跳转到登录界面
        next({ path: '/login' })
      } else {
        // 加载动态菜单和路由
        addDynamicMenuAndRoutes(userName, to, from)
        next()
      }
    }
  })
  
  /**
  * 加载动态菜单和路由
  */
  function addDynamicMenuAndRoutes(userName, to, from) {
    if(store.state.app.menuRouteLoaded) {
      console.log('动态菜单和路由已经存在.')
      return
    }
    api.menu.findNavTree({'userName':userName})
    .then(res => {
      // 添加动态路由
      let dynamicRoutes = addDynamicRoutes(res.data)
      router.options.routes[0].children = router.options.routes[0].children.concat(dynamicRoutes)
      router.addRoutes(router.options.routes)
      // 保存加载状态
      store.commit('menuRouteLoaded', true)
      // 保存菜单树
      store.commit('setNavTree', res.data)
    }).then(res => {
      api.user.findPermissions({'name':userName}).then(res => {
        // 保存用户权限标识集合
        store.commit('setPerms', res.data)
      })
    })
    .catch(function(res) {
    })
  }
  
  /**
  * 添加动态(菜单)路由
  * @param {*} menuList 菜单列表
  * @param {*} routes 递归创建的动态(菜单)路由
  */
  function addDynamicRoutes (menuList = [], routes = []) {
   var temp = []
   for (var i = 0; i < menuList.length; i++) {
     if (menuList[i].children && menuList[i].children.length >= 1) {
       temp = temp.concat(menuList[i].children)
     } else if (menuList[i].url && /\S/.test(menuList[i].url)) {
        menuList[i].url = menuList[i].url.replace(/^\//, '')
        // 创建路由配置
        var route = {
          path: menuList[i].url,
          component: null,
          name: menuList[i].name,
          meta: {
            icon: menuList[i].icon,
            index: menuList[i].id
          }
        }
        try {
          // 根据菜单URL动态加载vue组件，这里要求vue组件须按照url路径存储
          // 如url="sys/user"，则组件路径应是"@/views/sys/user.vue",否则组件加载不到
          let array = menuList[i].url.split('/')
          let url = ''
          for(let i=0; i<array.length; i++) {
            url += array[i].substring(0,1).toUpperCase() + array[i].substring(1) + '/'
          }
          url = url.substring(0, url.length - 1)
          route['component'] = resolve => require([`@/views/${url}`], resolve)
        } catch (e) {}
        routes.push(route)
     }
   }
   if (temp.length >= 1) {
     addDynamicRoutes(temp, routes)
   } else {
     console.log('动态路由加载...')
     console.log(routes)
     console.log('动态路由加载完成.')
   }
   return routes
  }
  
  export default router