protected function setThemeConstants()
    {
        $this->parsedHeaders = $this->headers($this->dirPath.'/style.css', $this->headers);

        // Theme text domain.
        $textdomain = (isset($this->parsedHeaders['text_domain']) && ! empty($this->parsedHeaders['text_domain']))
            ? $this->parsedHeaders['text_domain']
            : 'themosis_theme';

        defined('THEME_TD') ? THEME_TD : define('THEME_TD', $textdomain);
    }