import FungibleToken from 0xf233dcee88fe0abe import NonFungibleToken from 0x1d7e57aa55817448 import DapperUtilityCoin from 0xead892083b3e2c6c import MFLPlayer from 0x8ebcbfd516b1da27 import NFTStorefront from 0x4eb8a10cb9f87357 // This transaction purchases a Player on a peer-to-peer marketplace (i.e. **not** directly from a dapp). This transaction // will also initialize the buyer's Player collection on their account if it has not already been initialized. transaction(storefrontAddress: Address, merchantAccountAddress: Address, listingResourceID: UInt64, expectedPrice: UFix64) { let paymentVault: @{FungibleToken.Vault} let nftCollection: &MFLPlayer.Collection let storefront: &{NFTStorefront.StorefrontPublic} let listing: &{NFTStorefront.ListingPublic} let salePrice: UFix64 let balanceBeforeTransfer: UFix64 let mainDapperUtilityCoinVault: auth(FungibleToken.Withdraw) &DapperUtilityCoin.Vault prepare(dapper: auth(BorrowValue) &Account, buyer: auth(BorrowValue, IssueStorageCapabilityController, PublishCapability, UnpublishCapability, SaveValue) &Account) { // Initialize the MFLPlayer collection if the buyer does not already have one if buyer.storage.borrow<&MFLPlayer.Collection>(from: MFLPlayer.CollectionStoragePath) == nil { let collection <- MFLPlayer.createEmptyCollection(nftType: Type<@MFLPlayer.NFT>()) buyer.storage.save(<-collection, to: MFLPlayer.CollectionStoragePath) buyer.capabilities.unpublish(MFLPlayer.CollectionPublicPath) let collectionCap = buyer.capabilities.storage.issue<&MFLPlayer.Collection>(MFLPlayer.CollectionStoragePath) buyer.capabilities.publish(collectionCap, at: MFLPlayer.CollectionPublicPath) } // Get the storefront reference from the seller self.storefront = getAccount(storefrontAddress).capabilities.borrow<&{NFTStorefront.StorefrontPublic}>( NFTStorefront.StorefrontPublicPath ) ?? panic("Could not borrow Storefront for the seller") // Get the listing by ID from the storefront self.listing = self.storefront.borrowListing(listingResourceID: listingResourceID) ?? panic("No Offer with that ID in Storefront") self.salePrice = self.listing.getDetails().salePrice // Get a DUC vault from Dapper's account self.mainDapperUtilityCoinVault = dapper.storage.borrow(from: /storage/dapperUtilityCoinVault) ?? panic("Cannot borrow DapperUtilityCoin vault from account storage") self.balanceBeforeTransfer = self.mainDapperUtilityCoinVault.balance self.paymentVault <- self.mainDapperUtilityCoinVault.withdraw(amount: self.salePrice) // Get the collection from the buyer so the NFT can be deposited into it self.nftCollection = buyer.capabilities.borrow<&MFLPlayer.Collection>(MFLPlayer.CollectionPublicPath) ?? panic("Cannot borrow NFT collection receiver from account") } // Check that the price is right pre { self.salePrice == expectedPrice: "unexpected price" } execute { let item <- self.listing.purchase( payment: <-self.paymentVault ) self.nftCollection.deposit(token: <-item) // Remove listing-related information from the storefront since the listing has been purchased. self.storefront.cleanup(listingResourceID: listingResourceID) } // Check that all dapperUtilityCoin was routed back to Dapper post { self.mainDapperUtilityCoinVault.balance == self.balanceBeforeTransfer: "DapperUtilityCoin leakage" } }

Transaction