import auth from '@/plugins/auth'
import router, { constantRoutes, dynamicRoutes } from '@/router'
import { getRouters } from '@/api/menu'
import Layout from '@/layout/index'
import ParentView from '@/components/ParentView'
import InnerLink from '@/layout/components/InnerLink'

// 匹配views里面所有的.vue文件
const modules = import.meta.glob('./../../views/**/*.vue')

const usePermissionStore = defineStore(
  'permission',
  {
    state: () => ({
      routes: [],
      addRoutes: [],
      defaultRoutes: [],
      topbarRouters: [],
      sidebarRouters: []
    }),
    actions: {
      setRoutes(routes) {
        this.addRoutes = routes
        this.routes = constantRoutes.concat(routes)
      },
      setDefaultRoutes(routes) {
        this.defaultRoutes = constantRoutes.concat(routes)
      },
      setTopbarRoutes(routes) {
        this.topbarRouters = routes
      },
      setSidebarRouters(routes) {
        this.sidebarRouters = routes
      },
      generateRoutes(roles) {
        return new Promise(resolve => {
          // 向后端请求路由数据
          getRouters().then(res => {
            // 三份数据各自深拷贝后分别构建，normalizeRouteNames 是确定性的，
            // 因此三处得到的 name 完全一致，页签缓存不会对不上。
            const sdata = normalizeRouteNames(JSON.parse(JSON.stringify(res.data)))
            const rdata = normalizeRouteNames(JSON.parse(JSON.stringify(res.data)))
            const defaultData = normalizeRouteNames(JSON.parse(JSON.stringify(res.data)))
            const sidebarRoutes = filterAsyncRouter(sdata)
            const rewriteRoutes = filterAsyncRouter(rdata, false, true)
            const defaultRoutes = filterAsyncRouter(defaultData)
            const asyncRoutes = filterDynamicRoutes(dynamicRoutes)
            asyncRoutes.forEach(route => { router.addRoute(route) })
            this.setRoutes(rewriteRoutes)
            this.setSidebarRouters(constantRoutes.concat(sidebarRoutes))
            this.setDefaultRoutes(sidebarRoutes)
            this.setTopbarRoutes(defaultRoutes)
            resolve(rewriteRoutes)
          })
        })
      }
    }
  })

const isContainerRoute = (route) =>
  route.component === 'Layout' || route.component === 'ParentView' || route.component === 'InnerLink'

/**
 * 修正后端菜单里的路由重名。
 *
 * 两种情况 vue-router 4 会因重名丢路由或直接报错：
 * 1. 父容器与后代页面同名（如 /standardMaterial 容器与其下的标准物质清单页都叫
 *    StandardMaterial）——vue-router 3 允许，vue-router 4 抛
 *    "A route named X has been added as a child of a route with the same name"；
 * 2. 两个不同菜单项取了同一个 name（如两个「报告结果」都叫 ReportResults）——
 *    addRoute 时后者会把前者挤掉，被挤掉的那条路径就点不开了。
 *
 * 处理策略：先保留第一次出现的 name，后续重名一律加数字后缀。容器与后代叶子重名
 * 时优先改容器名（页面 name 与组件 name 一致，是页签缓存的键，尽量不动）。
 */
function normalizeRouteNames(routes) {
  const leafNames = new Set()
  const collectLeafNames = (list) => {
    list.forEach(route => {
      if (route.name && !isContainerRoute(route)) leafNames.add(route.name)
      if (route.children && route.children.length) collectLeafNames(route.children)
    })
  }
  collectLeafNames(routes)

  const used = new Set()
  const walk = (list) => {
    list.forEach(route => {
      if (route.name) {
        const conflict = used.has(route.name) ||
          (isContainerRoute(route) && leafNames.has(route.name))
        if (conflict) {
          let suffix = 2
          while (leafNames.has(`${route.name}${suffix}`) || used.has(`${route.name}${suffix}`)) suffix++
          route.name = `${route.name}${suffix}`
        }
        used.add(route.name)
      }
      if (route.children && route.children.length) walk(route.children)
    })
  }
  walk(routes)
  return routes
}

// 遍历后台传来的路由字符串，转换为组件对象
function filterAsyncRouter(asyncRouterMap, lastRouter = false, type = false) {
  return asyncRouterMap.filter(route => {
    if (type && route.children) {
      route.children = filterChildren(route.children)
    }
    if (route.component) {
      // Layout ParentView 组件特殊处理
      if (route.component === 'Layout') {
        route.component = Layout
      } else if (route.component === 'ParentView') {
        route.component = ParentView
      } else if (route.component === 'InnerLink') {
        route.component = InnerLink
      } else {
        route.component = loadView(route.component)
      }
    }
    if (route.children != null && route.children && route.children.length) {
      route.children = filterAsyncRouter(route.children, route, type)
    } else {
      delete route['children']
      delete route['redirect']
    }
    return true
  })
}

function filterChildren(childrenMap, lastRouter = false) {
  var children = []
  childrenMap.forEach(el => {
    el.path = lastRouter ? lastRouter.path + '/' + el.path : el.path
    if (el.children && el.children.length && el.component === 'ParentView') {
      children = children.concat(filterChildren(el.children, el))
    } else {
      children.push(el)
    }
  })
  return children
}

// 动态路由遍历，验证是否具备权限
export function filterDynamicRoutes(routes) {
  const res = []
  routes.forEach(route => {
    if (route.permissions) {
      if (auth.hasPermiOr(route.permissions)) {
        res.push(route)
      }
    } else if (route.roles) {
      if (auth.hasRoleOr(route.roles)) {
        res.push(route)
      }
    }
  })
  return res
}

export const loadView = (view) => {
  let res
  for (const path in modules) {
    const dir = path.split('views/')[1].split('.vue')[0]
    if (dir === view || dir === `${view}/index`) {
      res = () => modules[path]()
    }
  }
  return res
}

export default usePermissionStore