public function getChangelog($diff = null)
    {
        if (!$diff) {
            return $this->data['changelog'];
        }

        $diffLog = [];
        foreach ((array)$this->data['changelog'] as $version => $changelog) {
            preg_match("/[\w\-\.]+/", $version, $cleanVersion);

            if (!$cleanVersion || version_compare($diff, $cleanVersion[0], '>=')) {
                continue;
            }

            $diffLog[$version] = $changelog;
        }

        return $diffLog;
    }