public static function sendResponse(ResponseInterface $response)
    {
        header('HTTP/'.$response->getHttpVersion().' '.$response->getStatus().' '.$response->getStatusText());
        foreach ($response->getHeaders() as $key => $value) {
            foreach ($value as $k => $v) {
                if (0 === $k) {
                    header($key.': '.$v);
                } else {
                    header($key.': '.$v, false);
                }
            }
        }

        $body = $response->getBody();
        if (null === $body) {
            return;
        }

        if (is_callable($body)) {
            $body();

            return;
        }

        $contentLength = $response->getHeader('Content-Length');
        if (null !== $contentLength) {
            $output = fopen('php://output', 'wb');
            if (is_resource($body) && 'stream' == get_resource_type($body)) {
                if (PHP_INT_SIZE !== 4) {
                    // use the dedicated function on 64 Bit systems
                    stream_copy_to_stream($body, $output, (int) $contentLength);
                } else {
                    // workaround for 32 Bit systems to avoid stream_copy_to_stream
                    while (!feof($body)) {
                        fwrite($output, fread($body, 8192));
                    }
                }
            } else {
                fwrite($output, $body, (int) $contentLength);
            }
        } else {
            file_put_contents('php://output', $body);
        }

        if (is_resource($body)) {
            fclose($body);
        }
    }