import axios, { type InternalAxiosRequestConfig } from 'axios'
import { showToast } from 'vant'
import { portalAuthApi } from './portalAuth'

export class BizError extends Error {
  code?: number
  constructor(message: string, code?: number) {
    super(message)
    this.code = code
    this.name = 'BizError'
  }
}

/**
 * FastAPI 以 @router.get("/") + prefix 注册的集合根须带尾斜杠，否则 307 会丢 Authorization。
 * 发票夹路由是无尾斜杠的 /invoices、/invoice-ledgers、/invoice-wallets，切勿追加 `/`。
 * 与 web-admin/src/utils/http/bx.ts 保持一致。
 */
const BX_COLLECTION_ROOT =
  /^\/(reimburses|advances|payments|workflows|expense-items)$/

function normalizeBxUrl(url?: string): string | undefined {
  if (!url || url.endsWith('/')) return url
  return BX_COLLECTION_ROOT.test(url) ? `${url}/` : url
}

const bxClient = axios.create({
  baseURL: import.meta.env.VITE_API_URL || '/api',
  timeout: 0,
  headers: { 'Content-Type': 'application/json' },
})

let refreshing: Promise<boolean> | null = null

async function tryRefresh(): Promise<boolean> {
  const rt = localStorage.getItem('refreshToken')
  if (!rt) return false
  try {
    const res: any = await portalAuthApi.refreshToken(rt)
    const token = res?.data?.token
    const refreshToken = res?.data?.refreshToken
    if (!token) return false
    localStorage.setItem('accessToken', token)
    if (refreshToken) localStorage.setItem('refreshToken', refreshToken)
    return true
  } catch {
    return false
  }
}

bxClient.interceptors.request.use((config: InternalAxiosRequestConfig) => {
  if (config.url) config.url = normalizeBxUrl(config.url)
  if (config.data instanceof FormData) {
    delete (config.headers as any)['Content-Type']
  }
  const token = localStorage.getItem('accessToken')
  if (token) config.headers.Authorization = `Bearer ${token}`
  return config
})

bxClient.interceptors.response.use(
  (res) => {
    if (res.config.responseType === 'blob') return res.data
    const body = res.data
    if (body?.code !== undefined && body.code !== 0) {
      showToast(body.msg || '请求失败')
      return Promise.reject(new BizError(body.msg || '请求失败', body.code))
    }
    return body
  },
  async (err) => {
    const original = err.config
    if (err.response?.status === 401 && original && !(original as any)._retry) {
      ;(original as any)._retry = true
      if (!refreshing) {
        refreshing = tryRefresh().finally(() => {
          refreshing = null
        })
      }
      const ok = await refreshing
      if (ok) {
        original.headers = original.headers || {}
        original.headers.Authorization = `Bearer ${localStorage.getItem('accessToken')}`
        return bxClient.request(original)
      }
      localStorage.removeItem('accessToken')
      localStorage.removeItem('refreshToken')
      showToast('登录已过期，请重新登录')
      if (window.location.pathname !== '/login') {
        window.location.href = '/login'
      }
    } else if (err.response?.status !== 401) {
      const msg =
        err.response?.data?.msg || err.response?.data?.detail || err.message || '网络异常'
      showToast(msg)
    }
    return Promise.reject(err)
  },
)

export default bxClient