protected static function parseRss(\SimpleXMLElement $xml)
    {
        if (isset($xml->item)) {
            $items = $xml->item;
        } elseif (isset($xml->channel)) {
            $items = $xml->channel->item;
        } else {
            return false;
        }

        return [
            'url' => (string) $xml->channel->link,
            'items' => self::getRssItems($items),
        ];
    }