import { computed, ref } from 'vue'
import { defineStore } from 'pinia'

import { getCurrentUser, login as loginRequest, logout as logoutRequest } from '@/api/auth'
import type { AuthenticatedUser, LoginRequest, LoginResponse } from '@/types/auth'
import { clearAuthStorage, readStoredAuthSession, saveAuthSession } from '@/utils/auth-storage'

const dataScopeLabels: Record<AuthenticatedUser['dataScope'], string> = {
  ALL: '全院',
  CAMPUS: '院区',
  DEPARTMENT: '科室',
  READ_ONLY_ALL: '全院只读',
}

function getUserContext(user: AuthenticatedUser | null) {
  return user ? `${dataScopeLabels[user.dataScope]}数据范围` : '医签通用户'
}

export const useLoginStore = defineStore('login', () => {
  const storedSession = readStoredAuthSession()
  const token = ref(storedSession?.token ?? '')
  const expiresAt = ref(storedSession?.expiresAt ?? '')
  const user = ref<AuthenticatedUser | null>(storedSession?.user ?? null)
  const currentUserReady = ref(false)
  let currentUserRequest: Promise<AuthenticatedUser> | null = null

  const isLoggedIn = computed(() => Boolean(token.value))
  const userName = computed(() => user.value?.displayName || user.value?.username || '医护用户')
  const department = computed(() => getUserContext(user.value))

  function hasPermission(required: string | string[]) {
    const requiredPermissions = Array.isArray(required) ? required : [required]

    if (!requiredPermissions.length) {
      return true
    }

    const permissions = user.value?.permissions ?? []
    return requiredPermissions.every(
      (permission) => permissions.includes(permission) || permissions.includes('*'),
    )
  }

  function setSession(session: LoginResponse) {
    saveAuthSession(session)
    token.value = session.token
    expiresAt.value = session.expiresAt
    user.value = session.user
    currentUserReady.value = false
  }

  function setCurrentUser(nextUser: AuthenticatedUser) {
    user.value = nextUser

    if (token.value) {
      saveAuthSession({
        token: token.value,
        expiresAt: expiresAt.value,
        user: nextUser,
      })
    }
  }

  function clearSession() {
    clearAuthStorage()
    token.value = ''
    expiresAt.value = ''
    user.value = null
    currentUserReady.value = false
    currentUserRequest = null
  }

  async function login(payload: LoginRequest) {
    const session = await loginRequest(payload)
    setSession(session)
    return session
  }

  async function refreshCurrentUser() {
    const currentUser = await getCurrentUser()
    setCurrentUser(currentUser)
    return currentUser
  }

  async function ensureCurrentUser() {
    if (!token.value) {
      return null
    }

    if (currentUserReady.value && user.value) {
      return user.value
    }

    if (!currentUserRequest) {
      currentUserRequest = refreshCurrentUser()
        .then((currentUser) => {
          currentUserReady.value = true
          return currentUser
        })
        .catch((error: unknown) => {
          currentUserReady.value = false
          throw error
        })
        .finally(() => {
          currentUserRequest = null
        })
    }

    return currentUserRequest
  }

  async function logout() {
    try {
      await logoutRequest()
    } finally {
      clearSession()
    }
  }

  return {
    token,
    expiresAt,
    user,
    isLoggedIn,
    userName,
    department,
    login,
    refreshCurrentUser,
    ensureCurrentUser,
    hasPermission,
    logout,
    clearSession,
  }
})