protected function prepareConfig($contentTypeIdentifier)
    {
        if (!empty($this->config[ConfigurationConstants::CONTENT_TYPES][$contentTypeIdentifier])) {
            return $this->config[ConfigurationConstants::CONTENT_TYPES][$contentTypeIdentifier];
        }

        if (!empty($this->config['default'])) {
            return  $this->config['default'];
        }

        return array();
    }