public function setText($text = '', $clear = false)
    {
        if (true===$clear) {
            $this->clear('text');
        }
        if ('auto'==$text) {
            if (!empty($this->html)) {
                $html_content = preg_replace("/.*<body[^>]*>|<\/body>.*/si", "", $this->html);
                $this->text .= Helper::formatText(Helper::html2text($html_content));
            }
        } else {
            $this->text .= Helper::formatText($text);
        }
        return $this;
    }