Customize RulePartnerOrderEntryFixedDiscountRAOAction promotion action

Promotion Requirement : Cart contains a qualifying container 'X' worth $500, give $50 discount on 5 units of target container 'Y'. Container 'X' and 'Y' may contain a list of products.There should not be any restriction on the quantity of qualifying container when worth of the qualifying container is being mentioned. Assumption : 0 is passed in the qualifying container quantity in the action.

Approach followed : add the following parameters - 'qualifying container worth' parameter and an 'amount operator' parameter in the class overriding ootb RulePartnerOrderEntryFixedDiscountRAOAction.

Challenge : How do we determine the worth of container 'X' as the action does not know the quantity of quality container ? Is there any way to achieve this requirement in Hybris ?