/**
 * 地磅（db）模块 HTTP 客户端
 * 协议：直接 JSON 响应（与原 simple-dibang-xiaoshou 一致，非门户 code/data 信封）
 */
import axios, { type AxiosRequestConfig, type InternalAxiosRequestConfig } from 'axios'
import { ElMessage } from 'element-plus'
import { useUserStore } from '@/store/modules/user'
import { fetchRefreshToken } from '@/api/auth'

type RetryableConfig = InternalAxiosRequestConfig & {
  _retry?: boolean
  /** 为 false 时不弹出全局错误提示（由调用方自行处理） */
  showErrorMessage?: boolean
}

/** 地磅集合根路径（后端 @router.get("/") 注册，须带尾斜杠，否则 307 重定向会丢 Authorization） */
const DB_COLLECTION_ROOT = /^\/(plans|inventory|weighing)$/

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

const dbAxios = axios.create({
  baseURL: '/api',
  timeout: 60000,
  headers: { 'Content-Type': 'application/json' }
})

let isRefreshing = false
let pendingRequests: Array<{
  resolve: (token: string) => void
  reject: (error: unknown) => void
}> = []

function subscribeTokenRefresh(
  resolve: (token: string) => void,
  reject: (error: unknown) => void
) {
  pendingRequests.push({ resolve, reject })
}

function onRefreshed(newToken: string) {
  pendingRequests.forEach(({ resolve }) => resolve(newToken))
  pendingRequests = []
}

function onRefreshFailed(error: unknown) {
  pendingRequests.forEach(({ reject }) => reject(error))
  pendingRequests = []
}

/** 从 localStorage 兜底读取 accessToken（兼容 Pinia persist 的版本化 key） */
function readTokenFallback(): string {
  if (typeof localStorage === 'undefined') return ''
  try {
    for (const k of Object.keys(localStorage)) {
      if (!k.startsWith('sys-') || !k.includes('-user')) continue
      const raw = localStorage.getItem(k)
      if (!raw) continue
      const parsed = JSON.parse(raw) as { accessToken?: unknown }
      const token = parsed?.accessToken
      if (typeof token === 'string' && token.trim()) return token.trim()
    }
  } catch {
    // ignore
  }
  return ''
}

dbAxios.interceptors.request.use(async (config: InternalAxiosRequestConfig) => {
  if (config.url) {
    config.url = normalizeDbUrl(config.url)
  }
  const store = useUserStore()
  let token = store.accessToken as unknown as string
  if (!token) {
    token = readTokenFallback()
  }
  if (token) {
    if (typeof config.headers.set === 'function') {
      config.headers.set('Authorization', `Bearer ${token}`)
    } else {
      config.headers.Authorization = `Bearer ${token}`
    }
  }
  return config
})

dbAxios.interceptors.response.use(
  (res) => res.data,
  async (err) => {
    const status = err.response?.status
    const config = err.config as RetryableConfig | undefined

    if (status === 401 && config && !config._retry) {
      const userStore = useUserStore()
      const storedRefreshToken = userStore.refreshToken

      if (storedRefreshToken) {
        if (isRefreshing) {
          return new Promise((resolve, reject) => {
            subscribeTokenRefresh(
              (newToken: string) => {
                if (typeof config.headers.set === 'function') {
                  config.headers.set('Authorization', `Bearer ${newToken}`)
                } else {
                  config.headers.Authorization = `Bearer ${newToken}`
                }
                config._retry = true
                resolve(dbAxios.request(config))
              },
              (refreshError: unknown) => reject(refreshError)
            )
          })
        }

        isRefreshing = true
        config._retry = true
        try {
          const result = await fetchRefreshToken(storedRefreshToken)
          userStore.setToken(result.token, result.refreshToken)
          onRefreshed(result.token)
          if (typeof config.headers.set === 'function') {
            config.headers.set('Authorization', `Bearer ${result.token}`)
          } else {
            config.headers.Authorization = `Bearer ${result.token}`
          }
          return dbAxios.request(config)
        } catch (refreshError) {
          onRefreshFailed(refreshError)
          await userStore.logOut()
          return Promise.reject(refreshError)
        } finally {
          isRefreshing = false
        }
      }

      await userStore.logOut()
      return Promise.reject(err)
    }

    const showErrorMessage = config?.showErrorMessage !== false
    if (showErrorMessage) {
      const detail = err.response?.data?.detail
      const message =
        typeof detail === 'string'
          ? detail
          : Array.isArray(detail)
            ? detail.map((x: { msg?: string }) => x.msg).filter(Boolean).join('；')
            : err.response?.data?.msg
      ElMessage.error(message || err.message || '网络异常')
    }
    return Promise.reject(err)
  }
)

function request<T = unknown>(config: AxiosRequestConfig) {
  return dbAxios.request<any, T>(config)
}

const dbRequest = {
  get<T = unknown>(url: string, config?: AxiosRequestConfig) {
    return request<T>({ ...config, url, method: 'GET' })
  },
  post<T = unknown>(url: string, data?: unknown, config?: AxiosRequestConfig) {
    return request<T>({ ...config, url, method: 'POST', data })
  },
  put<T = unknown>(url: string, data?: unknown, config?: AxiosRequestConfig) {
    return request<T>({ ...config, url, method: 'PUT', data })
  },
  patch<T = unknown>(url: string, data?: unknown, config?: AxiosRequestConfig) {
    return request<T>({ ...config, url, method: 'PATCH', data })
  },
  delete<T = unknown>(url: string, config?: AxiosRequestConfig) {
    return request<T>({ ...config, url, method: 'DELETE' })
  }
}

export default dbRequest