const http = require('http');
const httpProxy = require('http-proxy');
const fs = require('fs');
const path = require('path');

const APP_URL = process.env.MAIN_URL || "http://localhost:3000";
const UPLOAD_DIR = process.env.UPLOAD_DIRECTORY || "/app/uploads";

// -------------------------------------------------------------------
// DÉTECTION DYNAMIQUE DU DOSSIER STATIC (Vérifié pour Hugging Face)
// -------------------------------------------------------------------
const possiblePaths = [
    path.join(__dirname, 'app', 'static'),
    path.join(__dirname, 'static'),
    '/app/app/static',
    '/app/static'
];

let foundPath = '';
for (const p of possiblePaths) {
    try {
        if (fs.existsSync(p) && fs.readdirSync(p).includes('terms.html')) {
            foundPath = p;
            break;
        }
    } catch (e) {
        // Dossier non accessible ou n'existe pas
    }
}

const STATIC_DIR = foundPath || possiblePaths[0];

// -------------------------------------------------------------------
// MVEMBA SYSTEM CONFIGURATION: PROXY v5.2.1 (Fix Double Declaration)
// -------------------------------------------------------------------
const proxyOptions = { ws: true, xfwd: true, cookieDomainRewrite: "", secure: false, changeOrigin: true };
const backendProxy = httpProxy.createProxyServer({ target: 'http://127.0.0.1:4000', ...proxyOptions });
const frontendProxy = httpProxy.createProxyServer({ target: 'http://127.0.0.1:4200', ...proxyOptions });

const errorHandler = (err, req, res) => {
    console.error(`[ERROR] ${new Date().toISOString()} : ${err.message}`);
    if (!res.headersSent) {
        res.writeHead(500, { 'Content-Type': 'text/plain' });
        res.end('MVEMBA_SYSTEM: Service temporarily unavailable.');
    }
};

backendProxy.on('error', errorHandler);
frontendProxy.on('error', errorHandler);

const setCacheHeaders = (res, ext) => {
    const oneDay = 24 * 60 * 60;
    if (['.mp4', '.webm', '.mov'].includes(ext)) {
        res.setHeader('Cache-Control', `public, max-age=${oneDay}`);
    } else {
        res.setHeader('Cache-Control', 'no-cache');
    }
};

const serveStaticFile = (res, filePath, contentType = 'text/html') => {
    if (fs.existsSync(filePath) && fs.statSync(filePath).isFile()) {
        res.writeHead(200, { 'Content-Type': contentType });
        fs.createReadStream(filePath).pipe(res);
    } else {
        console.error(`[404] File not found at: ${filePath}`);
        res.writeHead(404);
        res.end('File not found');
    }
};

// -------------------------------------------------------------------
// HTTP SERVER
// -------------------------------------------------------------------
const server = http.createServer((req, res) => {

    // TikTok Domain Verification
    if (req.url === '/tiktokPNM40yS7EF2dkzSNfJclFifdnpalsOMm.txt') {
        res.writeHead(200, { 'Content-Type': 'text/plain' });
        res.end('tiktok-developers-site-verification=PNM40yS7EF2dkzSNfJclFifdnpalsOMm');
        return;
    }

    // Static pages
    if (req.url === '/privacy') return serveStaticFile(res, path.join(STATIC_DIR, 'privacy.html'));
    if (req.url === '/terms') return serveStaticFile(res, path.join(STATIC_DIR, 'terms.html'));
    if (req.url === '/deletion') return serveStaticFile(res, path.join(STATIC_DIR, 'deletion.html'));

    req.headers['x-forwarded-proto'] = 'https';
    req.headers['x-forwarded-port'] = '443';
    if (req.headers.host) req.headers['x-forwarded-host'] = req.headers.host;

    if (req.url.startsWith('/uploads/')) {
        const filePath = path.join(UPLOAD_DIR, decodeURIComponent(req.url.replace('/uploads/', '')));
        if (fs.existsSync(filePath) && fs.statSync(filePath).isFile()) {
            setCacheHeaders(res, path.extname(filePath));
            fs.createReadStream(filePath).pipe(res);
            return;
        } else {
            res.writeHead(404);
            res.end('File not found');
            return;
        }
    }

    if (req.url.startsWith('/api') || req.url.startsWith('/public') || req.url.startsWith('/webhooks') || req.url.startsWith('/v1')) {
        if (req.url.startsWith('/api')) req.url = req.url.replace(/^\/api/, '') || '/';
        backendProxy.web(req, res);
    } else {
        frontendProxy.web(req, res);
    }
});

server.on('upgrade', (req, socket, head) => {
    if (req.url.startsWith('/api') || req.url.startsWith('/socket.io')) {
        if (req.url.startsWith('/api')) req.url = req.url.replace(/^\/api/, '') || '/';
        backendProxy.ws(req, socket, head);
    } else {
        frontendProxy.ws(req, socket, head);
    }
});

server.listen(3000, () => {
    console.log('------------------------------------------------------------');
    console.log('[STATUS] MVEMBA SECURE PROXY ENGINE v5.2.1 DEPLOYED');
    if (foundPath) {
        console.log(`[SUCCESS] Static files matched at: ${STATIC_DIR}`);
    } else {
        console.log(`[WARNING] Static directory not confirmed, using: ${STATIC_DIR}`);
    }
    console.log(`[TARGET] ${APP_URL}`);
    console.log('------------------------------------------------------------');
});