/**
 * 统一 API 请求封装，完全对齐 ai_uniapp_v2/utils/request.js
 *
 * 请求路径走 /api 前缀 → server/api/[...].js 服务端代理
 *   /api/user/info → 代理到 https://api.jiefuku.com/user/info
 *
 * 自动注入（对齐 V2）：
 *   Header: { token, timestr, nonce }
 *   Body:   { token, uid, mac, base_timestamp, client:1, source, client_ios, version, version_code }
 *
 * 后端响应规范：
 *   { code: 0,       data: {...}, list: [...], msg: '...' }   // 成功
 *   { code: 1000,    data: null,  msg: '...' }                // 业务异常
 *   { code: 1009,    data: null,  msg: '...' }                // 登录失效
 */
import md5 from '~/utils/md5'

export function useApi() {
  const tokenCookie = useCookie('token', { path: '/' })
  const macCookie = useCookie('mac', { maxAge: 365 * 24 * 3600, path: '/' })
  const openIdCookie = useCookie('open_id', { path: '/' })
  const sourceCookie = useCookie('source', { path: '/' })

  // mac 缺失时自动生成
  if (import.meta.client && !macCookie.value) {
    macCookie.value = generateUUID()
  }

  function generateUUID() {
    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
      const r = (Math.random() * 16) | 0
      const v = c === 'x' ? r : (r & 0x3) | 0x8
      return v.toString(16)
    })
  }

  /**
   * 生成 nonce + timestr（对齐 V2 getNonce）
   */
  function getNonce() {
    const timeStr = Date.now().toString()
    const str = md5(timeStr)
    const nonce = str.substring(4, 14)
    return { timeStr, nonce }
  }

  /**
   * 发起请求
   */
  async function request(path, options = {}) {
    const { method = 'GET', params, body } = options

    // 走 /api 代理，对齐 V2 H5 端的 BASE_URL = '/api'
    const url = '/api' + path

    const timestamp = Math.floor(Date.now() / 1000)
    const { timeStr, nonce } = getNonce()

    // Header 签名（对齐 V2 header 注入）
    const reqHeaders = {
      'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8',
      timestr: timeStr,
      nonce,
    }
    const token = tokenCookie.value
    if (token) reqHeaders.token = token

    // Body 公共参数（对齐 V2 data 注入）
    const commonParams = {
      token: token || '',
      uid: openIdCookie.value || '',
      mac: macCookie.value || '',
      base_timestamp: timestamp,
      client: 1,
      source: sourceCookie.value || '',
      client_ios: 0,
      version: '1.0.0',
      version_code: 1,
    }

    const fetchOptions = {
      method,
      headers: reqHeaders,
      onResponseError({ response }) {
        console.error('[useApi] HTTP Error', response.status, url)
      },
    }

    if (method === 'GET') {
      // GET: 参数拼接到 URL
      const allParams = { ...commonParams, ...(params || {}) }
      // 去除空字符串
      Object.keys(allParams).forEach((k) => {
        if (allParams[k] === '') delete allParams[k]
      })
      const queryStr = new URLSearchParams(allParams).toString()
      fetchOptions.query = allParams
      // GET 请求通过 server proxy 时，参数在 query 里
      const finalUrl = url + (queryStr ? '?' + queryStr : '')
      const result = await $fetch(finalUrl, fetchOptions)
      return handleResult(result)
    } else {
      // POST: body 为 x-www-form-urlencoded
      const postBody = { ...commonParams, ...(body || {}) }
      // 去除空字符串
      Object.keys(postBody).forEach((k) => {
        if (postBody[k] === '') delete postBody[k]
      })
      fetchOptions.body = new URLSearchParams(postBody).toString()

      const result = await $fetch(url, fetchOptions)
      return handleResult(result)
    }
  }

  /**
   * 统一处理响应
   */
  function handleResult(result) {
    if (result.code === 1009) {
      // 登录失效 → 触发登录弹窗
      if (import.meta.client) {
        const { logout } = useUser()
        logout()
        const showLogin = useState('showLogin', () => false)
        showLogin.value = true
      }
      const err = new Error(result.msg || '登录已失效，请重新登录')
      err.code = 1009
      throw err
    }

    if (result.code !== 0) {
      const err = new Error(result.msg || '请求失败')
      err.code = result.code || 1000
      throw err
    }

    return result
  }

  return {
    /** GET 请求 */
    get: (path, params) => request(path, { method: 'GET', params }),
    /** POST 请求 (x-www-form-urlencoded) */
    post: (path, body) => request(path, { method: 'POST', body }),
    /** 通用请求 */
    request,
  }
}