IPurchaseDiscountFacet

function initPurchaseDiscountFacet(bytes initPurchaseDiscountData) external

function setAndCheckPurchaseDiscount(bytes postFractioPurchaseDiscountData) external

function applyDiscount(uint256 campaignId, uint256 amountOfFractions, address account, bytes discountOperationData) external returns (uint256 pricePerFraction, uint256 idToProvide)