const express = require('express');
const proxy = require('express-http-proxy');
const app = express();

const targetUrl = 'https://api.openai.com';
const openaiKey = process.env.OPENAI_KEY;
const port = 7860;
const baseUrl = getExternalUrl(process.env.SPACE_ID);

let requestDetails = [];
let ipRequestCounts = {};

app.use('/api', (req, res, next) => {
  const ip = req.headers['x-forwarded-for'] || req.connection.remoteAddress;
  const currentCount = ipRequestCounts[ip] || 0;

  if (currentCount >= 2) {
    return res.status(429).send('You have reached your request limit of 10 messages. Please contact support for more details.');
  }

  ipRequestCounts[ip] = currentCount + 1;
  const timestamp = new Date().toISOString();
  const requestData = {
    requestNumber: ipRequestCounts[ip],
    ip: ip,
    timestamp: timestamp,
    text: req.method + ' ' + req.url
  };
  requestDetails.push(requestData);
  console.log(`Request ${requestData.requestNumber} from IP ${requestData.ip} on ${requestData.timestamp}`);

  next();
}, proxy(targetUrl, {
  proxyReqOptDecorator: (proxyReqOpts, srcReq) => {
    proxyReqOpts.headers['Authorization'] = 'Bearer ' + openaiKey;
    return proxyReqOpts;
  },
  userResDecorator: (proxyRes, proxyResData, userReq, userRes) => {
    if (proxyRes.statusCode === 429) {
      // Return a custom message for the 429 error from the proxy attempt
      return Buffer.from('Request limit reached on the proxied service. Please try again later.');
    }
    return proxyResData;  // Return original data if response is not 429
  }
}));

app.get("/", (req, res) => {
  let requestsInfo = requestDetails.map(detail =>
    `Request ${detail.requestNumber} from IP ${detail.ip} on ${detail.timestamp}`).join('<br>');
  res.send(`This is your OpenAI Reverse Proxy URL: ${baseUrl}.<br><br>${requestsInfo}`);
});

function getExternalUrl(spaceId) {
  const [username, spacename] = spaceId.split("/");
  return `https://${username}-${spacename.replace(/_/g, "-")}.hf.space/api/v1`;
}

app.listen(port, () => {
  console.log(`Reverse proxy server running on ${baseUrl}.`);
});