public function getCssClass()
    {
        $class = self::CLASS_DEFAULT;

        if ($this->userView) {
            if ($this->new_post_at > $this->userView->new_last_seen) {
                $class = self::CLASS_NEW;
            } elseif ($this->edited_post_at > $this->userView->edited_last_seen) {
                $class = self::CLASS_EDITED;
            }
        } else {
            $class = self::CLASS_NEW;
        }
        return $class;
    }