/**
 * Отправляет http-запрос от имени сервера.
 *
 * @param string $method
 * @param string $url
 * @param array $options['headers'] дополнительные заголовки
 * @param string $options['body'] тело запроса
 * @return mixed
 */
function proxy_request( $method, $url, $options = array() ) {
    $method = strtoupper($method);
    $parts = @parse_url($url);

    if ($parts === false) {
        die('url malformed');
    }

    $scheme = isset($parts['scheme']) ? strtolower($parts['scheme']) : 'http';

    if ($scheme != 'http' && $scheme != 'https') {
        die('only http and https are allowed');
    }

    $protocol = $scheme == 'http' ? 'tcp' : 'ssl';
    $host = strtolower( isset($parts['host']) ? $parts['host'] : getenv('HTTP_HOST') );
    $port = isset($parts['port']) ? $parts['port'] : ($protocol == 'tcp' ? 80 : 443);
    $uri = (isset($parts['path']) ? $parts['path'] : '/') . (isset($parts['query']) ? '?' . $parts['query'] : '');
    $request = "$method $uri HTTP/1.1\r\n";
    $request .= "Host: $host\r\n";
    $headers = isset($options['headers']) ? $options['headers'] : array();

    foreach ($headers as $k => $v) {
        $request .= "$k: $v\r\n";
    }

    $request .= "Connection: close\r\n\r\n";

    if ( isset($options['body']) ) {
        $request .= $options['body'];
    }

    $fp = @fsockopen("$protocol://$host", $port, $errno, $errstr, 5);

    if (!$fp) {
        die("could not connect: $errstr ($errno)");
    }

    fwrite($fp, $request);
    $cur = fgets($fp);

    if ( !preg_match('#^HTTP/(\d+\.\d+) ([1-5]\d{2})(.*)$#', $cur, $matches) ) {
        die('bad response');
    }

    $response = array();
    $response['scheme'] = $scheme;
    $response['host'] = $host;
    $response['port'] = $port;
    $response['uri'] = $uri;
    $response['http_version'] = $matches[1];
    $response['status'] = $matches[2];
    $response['status_text'] = trim($matches[3]);
    $headers = array();

    while ( !feof($fp) ) {
        $line = rtrim( fgets($fp) );

        if ($line === '') {
            break;
        }

        list($name, $value) = explode(': ', $line, 2);
        $name = strtolower($name);

        if ($name == 'set-cookie') {
            if ( !isset($headers[$name]) ) {
                $headers[$name] = array();
            }

            $headers[$name][] = $value;
        }
        else if ( isset($headers[$name]) ) {
            $headers[$name] .= ", $value";
        }
        else {
            $headers[$name] = $value;
        }
    }

    $body = '';
    $transfer_encoding = isset($headers['transfer-encoding']) ? strtolower($headers['transfer-encoding']) : '';
    $content_length = (int) @$headers['content-length'];

    if ($transfer_encoding == 'chunked') {
        while ( !feof($fp) ) {
            $block = rtrim( fgets($fp) );
            $size = (int) base_convert($block, 16, 10);
            // fread почему-то не читает строку указанного размера
            $chunk = stream_get_contents($fp, $size);
            $body .= $chunk;
            // пропускаем \r\n
            fread($fp, 2);
        }
    }
    else if ($content_length) {
        $body = stream_get_contents($fp, $content_length);
    }
    else {
        while ( !feof($fp) ) {
            $body .= fread($fp, 4096);
        }
    }

    $content_encoding = isset($headers['content-encoding']) ? strtolower($headers['content-encoding']) : '';
    // сжатые данные
    if ($content_encoding) {
        if ($content_encoding == 'gzip') {
            $body = gzdecode($body);
        }
        else if ($content_encoding == 'deflate') {
            $body = gzinflate($body);
        }
    }

    $response['headers'] = $headers;
    $response['body'] = $body;
    return $response;
}