import http from 'http';
import https from 'https';
import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const PORT = 3000;

const MIME = {
  '.html': 'text/html',
  '.js':   'application/javascript',
  '.css':  'text/css',
  '.json': 'application/json',
};

function proxyOnvista(req, res) {
  const url = new URL(req.url, `http://localhost:${PORT}`);

  // Forward all query params as-is to onvista
  const upstream = `https://api.onvista.de/api/v1/bonds/finder/configuration_query?${url.searchParams.toString()}`;

  const options = {
    headers: {
      'User-Agent': 'Mozilla/5.0',
      'Accept': 'application/json',
    }
  };

  https.get(upstream, options, upRes => {
    let body = '';
    upRes.on('data', chunk => body += chunk);
    upRes.on('end', () => {
      res.writeHead(upRes.statusCode, {
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*',
      });
      res.end(body);
    });
  }).on('error', err => {
    res.writeHead(502, { 'Content-Type': 'application/json' });
    res.end(JSON.stringify({ error: err.message }));
  });
}

function serveStatic(req, res) {
  const filePath = path.join(__dirname, 'static', req.url === '/' ? 'index.html' : req.url);
  const ext = path.extname(filePath);

  fs.readFile(filePath, (err, data) => {
    if (err) { res.writeHead(404); res.end('Not found'); return; }
    res.writeHead(200, { 'Content-Type': MIME[ext] || 'text/plain' });
    res.end(data);
  });
}

const server = http.createServer((req, res) => {
  if (req.url.startsWith('/api/bonds')) {
    proxyOnvista(req, res);
  } else {
    serveStatic(req, res);
  }
});

server.listen(PORT, () => console.log(`Bond Sniffer running at http://localhost:${PORT}`));