const superagent = require("superagent");

// Global cache for FastGPT Token
let cachedFastgptToken = null;

async function checkTokenValid(conf, token) {
   if (!token) return false;
   try {
      const res = await superagent
         .get(`${conf.fastGpt.apiUrl}/api/core/plugin/admin/tool/list`)
         .set({
            token,
         });
      return res?.status === 200;
   } catch (error) {
      const status = Number(error?.status || error?.response?.status || 0);
      const code = Number(error?.response?.body?.code || 0);
      // FastGPT token 失效时：HTTP 500 + body.code=403
      if (status === 500 && code === 403) return false;
      // 其他异常也按无效处理，触发刷新，确保返回可用 token
      return false;
   }
}

/**
 * Get FastGPT Token with caching
 * @param {Object} conf - Configuration object containing FastGPT credentials and API URL
 * @param {Boolean} forceRefresh - Whether to force refresh the token (default: false)
 * @param {Number} status - Interface status code (default: 200)
 * @returns {Promise<String>} - FastGPT Token
 */
async function getFastGptToken(conf, forceRefresh = false, status = 200) {
   // 缓存存在时，先探活，只有有效才返回缓存
   if (cachedFastgptToken && !forceRefresh && status != 403) {
      const valid = await checkTokenValid(conf, cachedFastgptToken);
      if (valid) return cachedFastgptToken;
   }

   try {
      let loginParams = {
         username: conf.fastGpt.username,
         password: conf.fastGpt.password,
         code: "",
      };

      const preLoginRes = await superagent
         .get(`${conf.fastGpt.apiUrl}/api/support/user/account/preLogin`)
         .query({
            username: conf.fastGpt.username,
         });

      if (
         preLoginRes.body &&
         preLoginRes.body.data &&
         preLoginRes.body.code === 200
      ) {
         loginParams.code = preLoginRes.body.data.code;
      }

      const res = await superagent
         .post(
            `${conf.fastGpt.apiUrl}/api/support/user/account/loginByPassword`
         )
         .send(loginParams);

      if (res.body && res.body.data && res.body.data.token) {
         cachedFastgptToken = res.body.data.token;
         console.log("FastGPT token refreshed successfully", Date.now());
         return cachedFastgptToken;
      }

      throw new Error("Failed to get FastGPT token");
   } catch (error) {
      console.error("Error getting FastGPT token:", error);
      throw error;
   }
}

module.exports = {
   getFastGptToken,
};