import FungibleToken from 0xf233dcee88fe0abe import NonFungibleToken from 0x1d7e57aa55817448 import UFC_NFT from 0x329feb3ab062d289 import DapperUtilityCoin from 0xead892083b3e2c6c import NFTStorefront from 0x4eb8a10cb9f87357 transaction(listingResourceID: UInt64, storefrontAddress: Address, expectedPrice: UFix64) { let paymentVault: @FungibleToken.Vault let UFC_NFTCollection: &UFC_NFT.Collection{NonFungibleToken.Receiver} let storefront: &NFTStorefront.Storefront{NFTStorefront.StorefrontPublic} let listing: &NFTStorefront.Listing{NFTStorefront.ListingPublic} let price: UFix64 let balanceBeforeTransfer: UFix64 let mainDapperUtilityCoinVault: &DapperUtilityCoin.Vault prepare(dapper: AuthAccount, buyer: AuthAccount) { // Initialize the buyer's collection if they do not already have one if buyer.borrow<&UFC_NFT.Collection>(from: UFC_NFT.CollectionStoragePath) == nil { // Create a new empty collection and save it to the account buyer.save(<-UFC_NFT.createEmptyCollection(), to: UFC_NFT.CollectionStoragePath) // Create a public capability to the UFC_NFT collection // that exposes the Collection interface buyer.link<&UFC_NFT.Collection{NonFungibleToken.CollectionPublic,UFC_NFT.UFC_NFTCollectionPublic}>( UFC_NFT.CollectionPublicPath, target: UFC_NFT.CollectionStoragePath ) } // Get the storefront reference from the seller self.storefront = getAccount(storefrontAddress) .getCapability<&NFTStorefront.Storefront{NFTStorefront.StorefrontPublic}>( NFTStorefront.StorefrontPublicPath )! .borrow() ?? panic("Could not borrow Storefront from provided address") // Get the listing by ID from the storefront self.listing = self.storefront.borrowListing(listingResourceID: listingResourceID) ?? panic("No Offer with that ID in Storefront") self.price = self.listing.getDetails().salePrice // Withdraw mainDapperUtilityCoinVault from Dapper's account self.mainDapperUtilityCoinVault = dapper.borrow<&DapperUtilityCoin.Vault>(from: /storage/dapperUtilityCoinVault) ?? panic("Cannot borrow DapperUtilityCoin vault from account storage") self.balanceBeforeTransfer = self.mainDapperUtilityCoinVault.balance self.paymentVault <- self.mainDapperUtilityCoinVault.withdraw(amount: self.price) // Get the collection from the buyer so the NFT can be deposited into it self.UFC_NFTCollection = buyer.borrow<&UFC_NFT.Collection{NonFungibleToken.Receiver}>( from: UFC_NFT.CollectionStoragePath ) ?? panic("Cannot borrow NFT collection receiver from account") } // Check that the price is right pre { self.price == expectedPrice: "unexpected price" } execute { let item <- self.listing.purchase( payment: <-self.paymentVault ) self.UFC_NFTCollection.deposit(token: <-item) // Be kind and recycle self.storefront.cleanup(listingResourceID: listingResourceID) } // Check that all dapperUtilityCoin was routed back to Dapper post { self.mainDapperUtilityCoinVault.balance == self.balanceBeforeTransfer: "dapperUtilityCoin leakage" } }

CODE_ERROR

Transaction