const express = require('express');
const axios = require('axios');
const NodeCache = require('node-cache');
const crypto = require('crypto');
const path = require('path');

const app = express();
const cache = new NodeCache();
let idCounter = 1;

// Serve static files (HTML, CSS, JS)
app.use(express.static(path.join(__dirname)));

// Main UI
app.get('/', (req, res) => {
  res.sendFile(path.join(__dirname, 'index.html'));
});

// Spotify Downloader UI
// Generate unique short key
function generateKey() {
  const id = idCounter++;
  const rand = crypto.randomBytes(3).toString('hex');
  return `${id}-${rand}`;
}

// Scrape via RapidAPI using provided API key
async function aio(url) {
  if (!url || !url.startsWith('https://')) throw new Error('Invalid URL');
  const apiKey = '1dda0d29d3mshc5f2aacec619c44p16f219jsn99a62a516f98';
  const { data } = await axios.post(
    'https://auto-download-all-in-one.p.rapidapi.com/v1/social/autolink',
    { url },
    {
      headers: {
        'content-type': 'application/json; charset=utf-8',
        'accept-encoding': 'gzip',
        'cache-control': 'no-cache',
        'referer': 'https://auto-download-all-in-one.p.rapidapi.com/',
        'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64)',
        'x-rapidapi-host': 'auto-download-all-in-one.p.rapidapi.com',
        'x-rapidapi-key': apiKey
      }
    }
  );
  return data;
}

/**
 * Endpoint to scrape & shorten media URLs
 * GET /proxy-url?url=<source_url>&ttlSeconds=<seconds>
 */
app.get('/proxy-url', async (req, res) => {
  const { url, ttlSeconds } = req.query;
  if (!url) return res.status(400).json({ error: 'Missing url parameter' });

  try {
    const result = await aio(url);
    if (result.data && Array.isArray(result.data.medias)) {
      result.data.medias = result.data.medias.map(media => {
        const key = generateKey();
        cache.set(key, media.url, ttlSeconds ? Number(ttlSeconds) : 0);
        return { ...media, url: `${req.protocol}://${req.get('host')}/proxy-url/d/${key}` };
      });
    }
    res.json(result);
  } catch (err) {
    console.error('Error in proxy-url:', err.message);
    res.status(500).json({ error: err.message });
  }
});

/**
 * Download proxy endpoint
 * GET /proxy-url/d/:key
 */
app.get('/proxy-url/d/:key', async (req, res) => {
  const key = req.params.key;
  const target = cache.get(key);
  if (!target) return res.status(404).send('Link expired or invalid');

  try {
    const response = await axios.get(target, { responseType: 'stream' });
    Object.entries(response.headers).forEach(([name, value]) => res.setHeader(name, value));
    response.data.pipe(res);
  } catch (err) {
    console.error('Download error:', err.message);
    res.status(502).send('Download failed');
  }
});

// Health check
app.get('/health', (req, res) => res.send('OK'));

const PORT = process.env.PORT || 7860;
app.listen(PORT, () => console.log(`AIO Downloader running on port ${PORT}`));