<?php
/**
 * GridTV — proxy.php
 * Playlists .m3u8 : fetch + réécriture URLs
 * Segments .ts    : streaming chunk par chunk (pas de buffering)
 */

$url = $_GET['url'] ?? '';
if (empty($url) || !preg_match('#^https?://#i', $url)) {
    http_response_code(400); die('Invalid URL');
}

$base = preg_replace('#[^/]*(\?.*)?$#', '', $url);
$path = parse_url($url, PHP_URL_PATH) ?? '';
$is_segment = preg_match('#\.(ts|aac|mp4|m4s|fmp4)(\?|$)#i', $path);

$headers = [
    'User-Agent: ' . ($_SERVER['HTTP_USER_AGENT'] ?? 'Mozilla/5.0'),
    'Accept: */*',
];

header('Access-Control-Allow-Origin: *');
header('Cache-Control: no-cache');

if ($is_segment) {
    // Streaming direct chunk par chunk — pas de buffering mémoire
    $opts = stream_context_create(['http' => [
        'method'          => 'GET',
        'header'          => implode("\r\n", $headers),
        'follow_location' => 1,
        'timeout'         => 30,
    ]]);

    $handle = @fopen($url, 'rb', false, $opts);
    if (!$handle) { http_response_code(502); die('Cannot open stream'); }

    // Récupérer le Content-Type de la réponse
    $ct = 'video/MP2T';
    foreach (($http_response_header ?? []) as $h) {
        if (preg_match('/^Content-Type:\s*(.+)/i', $h, $m)) { $ct = trim($m[1]); break; }
    }

    header('Content-Type: ' . $ct);
    header('X-Accel-Buffering: no');

    // Désactiver le buffering PHP
    if (ob_get_level()) ob_end_clean();
    
    while (!feof($handle)) {
        $chunk = fread($handle, 65536); // 64KB par chunk
        if ($chunk === false || $chunk === '') break;
        echo $chunk;
        flush();
    }
    fclose($handle);

} else {
    // Playlist .m3u8 — fetch complet puis réécriture
    $opts = stream_context_create(['http' => [
        'method'          => 'GET',
        'header'          => implode("\r\n", $headers),
        'follow_location' => 1,
        'timeout'         => 15,
        'ignore_errors'   => true,
    ]]);

    $body = @file_get_contents($url, false, $opts);
    if ($body === false) { http_response_code(502); die('Cannot reach upstream'); }

    $status_line = $http_response_header[0] ?? 'HTTP/1.1 200 OK';
    preg_match('#HTTP/\S+\s+(\d+)#', $status_line, $sm);
    if ((int)($sm[1] ?? 200) >= 400) { http_response_code((int)$sm[1]); die('Upstream error'); }

    header('Content-Type: application/vnd.apple.mpegurl');

    $proxy_base = (isset($_SERVER['HTTPS']) ? 'https' : 'http')
                . '://' . $_SERVER['HTTP_HOST']
                . strtok($_SERVER['REQUEST_URI'], '?')
                . '?url=';

    $lines = explode("\n", $body);
    $out   = [];
    foreach ($lines as $line) {
        $line = rtrim($line);
        if ($line === '' || $line[0] === '#') {
            $line = preg_replace_callback('/URI="([^"]+)"/', function($m) use ($base, $proxy_base) {
                $seg = strpos($m[1], 'http') === 0 ? $m[1] : $base . $m[1];
                return 'URI="' . $proxy_base . urlencode($seg) . '"';
            }, $line);
            $out[] = $line;
        } else {
            $seg = strpos($line, 'http') === 0 ? $line : $base . $line;
            $out[] = $proxy_base . urlencode($seg);
        }
    }
    echo implode("\n", $out);
}