DiscountBase::getSiteCurrency

protected function getSiteCurrency()
{
	$result = InternalsSiteCurrencyTable::getCurrency($this->getSiteId());;
	if (is_array($result))
		return $result['CURRENCY'];
	$result = (string)MainConfigOption::get('sale', 'default_currency');
	if ($result !== '')
		return $result;
	$result = CurrencyCurrencyManager::getBaseCurrency();
	if ($result !== '')
		return $result;
	return null;
}