import axios from 'axios'
import { useAuthStore } from '@/stores/auth'
import { Message } from '@/components/ui'

const AUTH_ERROR_CODE = 401
const SESSION_REPLACED_CODE = 40101

const http = axios.create({
  baseURL: import.meta.env.VITE_API_BASE_URL || '/api',
  timeout: 15000,
  headers: {
    Accept: 'application/json',
    'Content-Type': 'application/json',
  },
})

let redirectingToLogin = false

function redirectToLogin(reason) {
  const currentPath = window.location.pathname.replace(/\/+$/, '') || '/'
  if (currentPath === '/login' || redirectingToLogin) return

  redirectingToLogin = true
  const redirect = `${window.location.pathname}${window.location.search}${window.location.hash}`
  const query = new URLSearchParams({ redirect })
  if (reason) query.set('reason', reason)
  window.location.assign(`/login?${query.toString()}`)
}

function isAuthenticationError(code) {
  return code === AUTH_ERROR_CODE || code === SESSION_REPLACED_CODE
}

function handleUnauthorized(code) {
  const authStore = useAuthStore()
  authStore.clearSession()
  redirectToLogin(code === SESSION_REPLACED_CODE ? 'session-replaced' : 'expired')
}

// 请求拦截器：注入 Bearer token（调用时读取 store，保证 pinia 已激活）
http.interceptors.request.use((config) => {
  const authStore = useAuthStore()
  if (authStore.loginInfo.token) {
    config.headers.Authorization = `Bearer ${authStore.loginInfo.token}`
  }
  return config
})

// 响应拦截器：统一按 ApiResult 结构处理
http.interceptors.response.use(
  (response) => {
    const payload = response.data

    // 文件下载（导出等）：blob 响应没有 code 字段，原样透传响应本身，
    // 调用方才能读到 headers（Content-Disposition 里的文件名、content-type 用于区分错误 JSON）
    if (typeof Blob !== 'undefined' && payload instanceof Blob) {
      return response
    }

    // 无 code 字段时按成功透传
    if (payload?.code === undefined) {
      return {
        success: true,
        code: 0,
        message: '',
        data: payload,
      }
    }

    payload.success = payload.code === 0

    if (payload.success) return response

    if (isAuthenticationError(payload.code)) handleUnauthorized(payload.code)

    const err = new Error(payload.message || '请求失败')
    err.code = payload.code
    err.data = payload.data
    err.success = payload.success
    throw err
  },
  (error) => {
    const status = error.response?.status
    const payload = error.response?.data

    // 仅鉴权类错误（401 / 40101）才清会话并跳登录页；
    // 网络异常（无 status）、服务器 5xx 等普通错误不应把用户登出
    const errorCode = payload?.code ?? status ?? 0
    if (isAuthenticationError(errorCode)) handleUnauthorized(errorCode)

    const message =
      payload?.message ||
      (error.code === 'ECONNABORTED' ? '请求超时，请稍后重试' : '网络异常，请检查服务是否正常')

    const requestError = new Error(message)
    requestError.code = payload?.code ?? status ?? -1
    requestError.data = payload?.data
    requestError.success = false

    // 服务端不可达（无 status）/ 5xx 属全局性问题，统一弹 Message 提示；
    // 4xx 等业务错误由调用方自行决定提示方式。
    // 打 toasted 标记：登录、上传/删除等已有自身 Message 的调用方据此去重，避免重复弹窗
    if (!status || status >= 500) {
      Message.error(message)
      requestError.toasted = true
    }

    throw requestError
  },
)

export function post(path, data, config) {
  return http.post(path, data, config).then((r) => r.data)
}

export function put(path, data, config) {
  return http.put(path, data, config).then((r) => r.data)
}

export function get(path, params, config) {
  return http.get(path, { params, ...config }).then((r) => r.data)
}

export default http