protected function getContentRange($header)
    {
        if (preg_match('/(?P<unit>[\w]+)\s+(?P<first>\d+)-(?P<last>\d+)\/(?P<length>\d+|\*)/', $header, $matches)) {
            $return = [];

            $return['unit'] = $matches['unit'];
            $return['first'] = (int) $matches['first'];
            $return['last'] = (int) $matches['last'];
            $return['length'] = is_numeric($matches['length']) ? (int) $matches['length'] : '*';

            return $return;
        }

        return false;
    }