$ip = isset($_SERVER['HTTP_X_FORWARDED_FOR']) ? $_SERVER['HTTP_X_FORWARDED_FOR'] : $_SERVER['REMOTE_ADDR'];
    $header = array('http' => array('method' => 'GET', 'header' => 'User-Agent: ' . user_agent . "\r\n" . 'X-Forwarded-For: ' . $ip));
    $context = stream_context_create($header);
    $data = file_get_contents($request, false, $context);
    return $data;
}

if (file_exists('index.html')) {
    $content = file_get_contents('index.html');
    $encoding = mb_detect_encoding($content, array('UTF-8', 'GB2312', 'GBK', 'ISO-8859-1'), true);

    if ($encoding == 'UTF-8') {
        header('Content-Type: text/html; charset=UTF-8');
        echo $content;
    } elseif ($encoding == 'GB2312' || $encoding == 'GBK') {
        header('Content-Type: text/html; charset=GB2312');
        echo mb_convert_encoding($content, 'GB2312', $encoding);
    } else {
        header('Content-Type: text/html; charset=UTF-8');
        echo mb_convert_encoding($content, 'UTF-8', $encoding);
    }
} else {
    echo "index.html file not found.";
}