Method getDefaultCurrency

public static function getDefaultCurrency()
{
    if (self::$defaultcurrency === false) {
        $db = Factory::getDBO();
        $query = ' SELECT a.id FROM #__phocacart_currencies AS a' . ' WHERE a.exchange_rate = 1' . ' ORDER BY a.id';
        $db->setQuery($query);
        $c = $db->loadObject();
        if (!empty($c->id)) {
            self::$defaultcurrency = (int) $c->id;
        } else {
            self::$defaultcurrency = false;
        }
    }
    return self::$defaultcurrency;
}