import constant from './const'

export function getRouters (files) {

  let filenames = files.keys()

  let list = mapToList(filenames)

  let routerArr = getTree(list)

  return routerArr

}

function getTree (list) {

  let routers = []

  list.map((obj, index) => {

    // 当前菜单没有父菜单

    if (!hasParent(obj)) {

      let length = 0

      let routerArr = findChild(obj, obj, list, length)

      routers = routers.concat(routerArr)

      return routers

    }

  })

  return routers

}

function hasParent (node) {

  let arr = node.split('/')

  if (arr.length > 1) {

    return arr[arr.length - 2]

  } else {

    return null

  }

}

function findChild (node, path, list, length) {

  let routerArr = []

  let childrenArr = []

  let name = node

  if (endsWith(node, constant.end)) {

    node = cleanAuth(node, constant.end)

  }

  list.map((obj, index) => {

    let arr = obj.split('/')

    if (node === arr[length]) {

      if (arr.length === length + 2) {

        arr.splice(0, length + 1)

        let tempNode = arr.toString().replace(',', '/')

        childrenArr = childrenArr.concat(findChild(tempNode, obj, list, length + 1))

      }

      return childrenArr

    }

  })

  routerArr = packageRouter(name, path, routerArr, childrenArr)

  return routerArr

}

function packageRouter (name, route, routerArr, childrenArr) {

  // path = path.toLocaleLowerCase()

  // ../components 不能为第一个变量，否则会报错Cannot find module "."

  let path = constant.prefix + '/' + route

  if (endsWith(route, constant.end)) {

    let tempRoute = cleanAuth(route, constant.end)

    if (childrenArr === 'undefined' || childrenArr.length === 0) {

      routerArr.push({

        path: '/' + tempRoute,

        name: tempRoute,

        component: resolve => require([`@/${path}.vue`], resolve),

        meta: {

          requireAuth: true

        }

      })

    } else {

      routerArr.push({

        path: '/' + tempRoute,

        name: tempRoute,

        component: resolve => require([`@/${path}.vue`], resolve),

        meta: {

          requireAuth: true

        },

        children: childrenArr

      })

    }

    return routerArr

  } else {

    if (childrenArr === 'undefined' || childrenArr.length === 0) {

      routerArr.push({

        path: '/' + route,

        name: route,

        component: resolve => require([`@/${path}.vue`], resolve)

      })

    } else {

      routerArr.push({

        path: '/' + route,

        name: route,

        component: resolve => require([`@/${path}.vue`], resolve),

        children: childrenArr

      })

    }

    return routerArr

  }

}

function mapToList (filenames) {

  let list = []

  filenames.map((obj, index) => {

    obj = obj.replace(/^\.\//, '').replace(/\.(vue)$/, '')

    list.push(obj)

  })

  return list

}

// 判断当前字符串是否以str开始

// function startsWith (str) {

//   return this.slice(0, str.length) === str

// }

// 判断当前字符串是否以str结束

function endsWith (origin, str) {

  if (!judgeStrLength) {

    return false

  }

  return origin.slice(origin.length - str.length, origin.length) === str

}

function cleanAuth (origin, str) {

  if (!judgeStrLength) {

    return origin

  }

  return origin.slice(0, origin.length - str.length)

}

function judgeStrLength (origin, str) {

  return origin.length - str.length > 0

}

export default getRouters