public function getShopUrl($lang = null, $admin = null)
    {
        $url = null;
        $admin = isset($admin) ? $admin : $this->isAdmin();

        if (!$admin) {
            $url = $this->getShopUrlByLanguage($lang);
            if (!$url) {
                $url = $this->getMallShopUrl();
            }
        }

        if (!$url) {
            $url = $this->getConfigParam('sShopURL');
        }

        return $url;
    }