import Vue from 'vue'
import Router from 'vue-router'
import store from '@/store'

Vue.use(Router)
const router = new Router()
// 全局前置守卫
router.beforeEach( async (to, from, next) => {
 let userRoutes = store.state.global.userRoutes //userRoutes 当前用户拥有的权限
 if (userRoutes.length && !userRoutes.filter(item => item.path == to.path).length) {
  next(from.path)
  return
 }
 next()
})
export default router

//state.js
export default {
 // 全部路由
 allRoutes: [
  //登录页面
  {
   path: '/demo',
   name: 'demo',
   component: () => import('@/views/demo')
  },
  {
   path: '*',
   redirect: '/demo'
  },
  //主页面
  {
   path: '/',
   component: () => import('@/views'),
  },
  {
   path: '/home',
   name: 'home',
   component: () => import('@/views/home')
  }
 ],
 // 用户匹配的路由,要用addRoutes添加到route
 userRoutes: [],
 // 渲染用户菜单
 userMenus: []
}

数据返回时格式
menu = [
 {id: 1, name: '首页', path: '/home', parentId: 0},
 {id: 2, name: '系统设置', path: '', parentId: 0},
 {id: 3, name: '角色配置', path: '/roles', parentId: 2},
 {id: 4, name: '用户配置', path: '/users', parentId: 2}
]
需要处理成
menu = [
 {id: 1, name: '首页', path: '/home', parentId: 0},
 {id: 2, name: '系统设置', path: '', parentId: 0, 
   child: [
     {id: 3, name: '角色配置', path: '/roles', parentId: 2},
     {id: 4, name: '用户配置', path: '/users', parentId: 2}
    ]
  },
]

//actions.js

// 获取当前用户权限
 getMenu: async ({ state, commit, dispatch }) => {
  //请求当前用户所拥有的权限
  let result = await axios('/api/menu/find')
  if (result.data.code > 0) {
   let userRoutes = result.data.result
   userRoutes.forEach(item => {
    item.child = []
    state.allRoutes.forEach(res => {
     if (item.path == res.path) {
      item.component = res.component
     }
    })
   })
   let oneArr = [], anotherArr = []  //oneArr 一级路由 anotherArr 其他级别路由
   oneArr = userRoutes.filter(item => !item.parentId)
   anotherArr = userRoutes.filter(item => item.parentId)
   anotherArr.forEach(item => {
    oneArr.forEach(obj => {
     if (item.parentId == obj.id) { //如果匹配 说明找到父级，直接push到父级的child里面
      if (!obj.child.filter(k => k.id == item.id).length) {
       obj.child.push(item)
      }
     } else {  //如果没有，说明本级路由没有找到，去下一级别路由找父级 路由级别：1级路由，2级路由，3级路由......
      dispatch('recurrArr', {arr: oneArr, items: item})
     }
    })
   })
   commit('setState', {state: 'userRoutes', value: userRoutes})
   commit('setState', {state: 'userMenus', value: oneArr})
   return {code: 1, data: userRoutes}  //处理完成后返回 oneArr是递归处理后嵌套的，userRoutes是获取到component来渲染route的
  } else {
   return {code: 0}
  }
 },
 // 递归找自己的parentId
 recurrArr: ({dispatch}, {arr, items}) => {
  if (!arr) {
   return
  }
  for(let i = 0; i < arr.length; i ++ ){
   let item = arr[i]
   if (item.id == items.parentId) {
    if (!item.child.filter(k => items.id == k.id).length) {
     item.child.push(items)
    }
    break;
   } else {
    dispatch('recurrArr', {arr: item.child, items: items})
   }
  }
 }

// 登录
 login: async ({ commit, dispatch}, params) => {
  let result = await axios('/api/login', {params})
  if(result.data.code > 0) {
   // 登录成功以后 获取当前用户权限路由
   let userRoutes = await dispatch('getMenu')
   if (userRoutes.code > 0) {
    // 把请求回来的路由动态添加到 route 里
    router.addRoutes(userRoutes.data)
    // 添加完成后，现在可以跳转到首页了~
    router.push('/home')
   }
   return {code: 1, data: result.data}
  } else {
   console.log(result.data.msg)
   return {code: 0}
  }
 },

axios.interceptors.response.use(
 response => {
  if (response.status === 200) {
   // 身份验证失败 
   if(response.data.code === -1) {
    // 执行退出登录
    store.dispatch('global/loginOut')
   } else {
    // 如果请求头里有token
    let token = response.headers.token
    if(token) {
     localStorage.setItem('token', token)
     axios.defaults.headers.token = token
    }
   }
   return Promise.resolve(response)
  } else {
   return Promise.reject(response)
  }
 }
)

 // 退出登录
 loginOut: async ({ state }) => {
  // 退出登录清空 token 和 headers 里面的 token
  localStorage.removeItem('token')
  delete axios.defaults.headers.token
  // 退出登录要动态添加 登录页面 和 * 重定向页面
  let errRoutes = state.allRoutes.filter(item => item.path == '*')
  errRoutes.push(state.allRoutes.filter(res => errRoutes[0].redirect == res.path)[0])
  router.addRoutes(errRoutes);
  router.currentRoute.path !== '/demo' "/demo") : null
 
  let result = await axios('/api/loginOut', {params: {userId: state.userId}})
  if(result.data.code !== 1) {
   console.log('退出登录接口异常')
  }
 },