const express = require('express');
const morgan = require('morgan');
const { createProxyMiddleware } = require('http-proxy-middleware');

const app = express();

// Configuration
const PORT = process.env.PORT || 3001;
const API_SERVICE_URL = process.env.VITE_API_PROXY_TARGET;
const API_KEY = process.env.VITE_API_KEY;

if (!API_SERVICE_URL) {
  throw new Error('VITE_API_PROXY_TARGET environment variable is not set.');
}
if (!API_KEY) {
  throw new Error('VITE_API_KEY environment variable is not set.');
}

// Logging
app.use(morgan('dev'));

// Proxy middleware
app.use('/api', createProxyMiddleware({
  target: API_SERVICE_URL,
  changeOrigin: true,
  pathRewrite: {
    '^/api': '', // remove /api prefix when forwarding to the target
  },
  onProxyReq: (proxyReq, req, res) => {
    // Add the API key to the request header
    proxyReq.setHeader('X-API-KEY', API_KEY);
  },
  onError: (err, req, res) => {
    console.error('Proxy error:', err);
    res.status(500).send('Proxy error');
  }
}));

app.listen(PORT, () => {
  console.log(`BFF server listening on port ${PORT}`);
});