What currency code should be used in the payment extension (module) in Magento 1.9 for making payments? Is it should be returned by:
Mage::app()->getStore()->getCurrentCurrencyCode()
Mage::app()->getStore()->getBaseCurrencyCode()
or by method 'getOrderCurrencyCode' of the order? What total amount of the order should be get for making payments? From the order method 'getBaseGrandTotal' or 'getGrandTotal'? What total amount and currency code the payment should be initiated with? I am creating a payment extension which allow to pay with digital money in many currencies but only PLN and GBP are available practically. Could you help me?