Marketplace owner. Marketplace owner can

• Set marketplace wallet via setMarketplaceWallet
• Set marketplace fee portion, by per-ten-thousand unit of portions via setMarketplaceFeePortion
• Set ERC20 token for timed auction payment via setERC20TokenForAuction
• Stop an ongoing auction or sale via stopAuction, i.e. after the duration of the auction or sale has ended
  • Requirements.
    • Only marketplace owner can stop an on-going sale or auction
  • Actions and events.
    • The auction or sale will be marked as stopped
    • If no offer or bid is made, the NFTs deposited to the marketplace will be transferred back to the seller, and the auction or sale will be deleted
    • Event AuctionStopped(_auctionId) will be emitted upon successful stop

NFT seller. NFT sellers can

• Settle a stopped auction via settleAuction, i.e. take a particular offer or the highest one and sell the NFTs
  • Requirements.
    • Only NFT seller can settle an auction or sale by taking a bid or offer
    • The indicated auction or sale must be stopped previously
    • The indicated offer or bid must be made previously
  • Actions and events.
    • The chosen buyer will pay the marketplace fee and seller fee in Wei (for fixed-price sale) or WETH (for timed auction and declining-price sale)
    • The NFTs are lazily minted and transferred to the recipient indicated by the buyer
    • All offers or bids made by other users will be transferred back to them
    • The auction or sale is then deleted
    • Event NFTTransferredAndSellerPaid will be emitted upon successful settle
• Withdraw an auction or sale via withdrawAuction, i.e. this function will transfer all bids or offers back to their bidders
  • Requirements.
    • Only NFT seller or marketplace owner can withdraw a sale or auction, i.e. the marketplace owner may decide to withdraw an auction which last for too long without being settled
  • Actions and events.
    • All NFTs transferred from the seller to the marketplace is transferred back to the seller
    • All offers or bids made by ordinary users will be transferred back to them
    • The auction or sale is then deleted
    • Event AuctionWithdrawn(_auctionId) will be emitted upon successful withdraw
• Update whitelisted buyer of an ongoing fixed-price sale, where there is no bidder yet, via updateWhitelistedBuyer
  • Requirements.
    • Only NFT seller can invoke updateWhitelistedBuyer
    • Whitelisted buyer can only be updated for an on-going fixed-price sale, where no offer has been made
  • Actions and events.
    • Event WhitelistedBuyerUpdated(_auctionId, _newWhitelistedBuyer) will be emitted upon successful update
• Update the reserve price of an ongoing timed auction, where the old reserve price has not been met, via updateMinimumPrice
  • Requirements.
    • Only NFT seller can invoke updateMinimumPrice()
    • Min price can only be updated for an on-going timed auction
    • The newly min price must not be higher than the current buy-now price
  • Actions and events.
    • Event MinimumPriceUpdated(_auctionId, _newMinPrice) will be emitted upon successful update
• Update the buy-now price of an ongoing timed auction or fixed-price sale via updateBuyNowPrice
  • Requirements.
    • Only NFT seller can invoke updateBuyNowPrice()
    • Buy-now price cannot be udpated for declining-price sale, since it is treated as starting price for such a sale
    • NFT seller can only update buy-now price of an on-going fixed-price sale or timed auction
    • The new buy-now price must not be lower than the current reserve price (min price)
  • Actions and events.
    • Event BuyNowPriceUpdated(_auctionId, _newBuyNowPrice) will be emitted upon successful update
    • If the current highest bid or offer meets the newly updated buy-now price, the offer will be immediately taken and the sale is finished
• Take an offer and terminate an ongoing fixed-price sale via takeOffer
  • Requirements.
    • Only NFT seller can invoke takeOffer()
    • NFT seller can only take offer from an on-going fixed-price sale
  • Actions and events.
    • Event OfferTaken(_auctionId, _bidId) will be emitted upon successful invocation

Ordinary users. Ordinary users can

• Create NFT timed-auction via createNftAuction
  • Actions and events.
    • Event NftAuctionCreated(auctionId) is emitted upon successful sale creation
• Create NFT fixed-price sale via createSale
  • Actions and events.
    • Event SaleCreated(auctionId) is emitted upon successful sale creation
• Create NFT declining-price sale via createDecliningPriceSale
  • Actions and events.
    • Event DecliningPriceSaleCreated(auctionId) is emitted upon successful sale creation
• Make bid, purchase, or make offer to an ongoing auction, via makeBid
  • Requirements.
    • NFT seller cannot make offer or bid to his own sale or auction
    • Bids to fixed-price sales must be paid in Wei, while bids to timed auction and declining-price sale must be paid in WETH
    • For fixed-price sale, the bid must be at least the nailed buy-now price, otherwise the bid must be an offer
    • For timed auction, the bid must be at least the min price, and higher than the current highest bid by a certain percentage
    • For declining-price sale, the bid must be at least the current price of the sale
    • If the sale is a direct fixed-price sale, i.e. with whitelisted buyer, only the whitelisted buyer can make a bid or offer
  • Actions and events.
    • The corresponding cash will be transferred to the marketplace
    • The highest bid ID will automatically updated
    • Event BidMade(auctionId, bidId, bidder, bidAmount) will be emitted upon successful bid
    • If the buy-now price is met, for any type of auction or sale, the bid is taken and the auction or sale is terminated
    • In case of declining-price sale, the bid is taken immediately and the sale is terminated
• Withdraw the bid from an ongoing auction via withdrawBid
  • Requirements.
    • Bidder can only withdraw bid from an on-going auction
    • Only bidder can withdraw his own bids
  • Actions and events.
    • The highest bid is re-picked
    • If no highest bid can be picked, i.e. all bidders has drawn their bid, the number of bids is set to zero
    • The withdrawn cash will be saved as credits at the marketplace, and the withdrawer can get the cash later via withdrawAllCredits
    • Event BidWithdrawn(_auctionId, _bidId, _newHighestBidId) will be emitted upon successful withdraw
• Withdraw all credited Wei and ERC20 from the marketplace via withdrawAllCredits

Ordinary working flow.

1. NFT author creates NFT (if not available) with ArtToken.create(initialOwner, initialSupply, uri, data)

   • Arguments.

     • initialOwner is the address of the initial owner, i.e. if initialOwner is not zero, then an amount of initialSupply of the NFT is minted and assigned to initialOwner
     • initialSupply is the amount of initially minted NFTs
     • uri is the URI of the NFT metadata
     • data is a 64-byte binary string. Should be zero binary string

   • Example.

     const ZERO_ADDRESS = web3.utils.padLeft(web3.utils.toHex(0), 40);
     const EMPTY_BYTES = web3.utils.padLeft(web3.utils.toHex(0), 64);
     const SAMPLE_URI = "https://web.skype.com/"
     
     receipt = await arttoken.create(
         ZERO_ADDRESS, 0, SAMPLE_URI, EMPTY_BYTES
     );

2. Seller create sale with Marketplace.createSale(artTokenContractAddress, tokenIds, quantities, buyNowPrice, whitelistedBuyer)

   • Arguments.

     • artTokenContractAddress is the address of ArtToken contract
     • tokenIds is the IDs of the NFTs for sale
     • quantities is the quantities of each NFT for sale
     • whitelistedBuyer is the address of the whitelisted buyer. Set this to zero to indicate no whitelisted buyer

   • Example.

     receipt = await marketplace.createSale(
         arttoken.address, createdTokenIds, quantitiesForSale, 
         nftPrice, ZERO_ADDRESS
     );

3. Buyer make a bid to the sale with Marketplace.makeBid(auctionId, nftRecipient, tokenAmount, isOffer)

   • Arguments.

     • auctionId is the ID of the sale to make bid or offer
     • nftRecipient is the address of the NFT recipient in case of successful purchase. Set to zero in case the buyer is the recipient
     • tokenAmount is the amount of WETH used for payment (should be zero for fixed-price sale)
     • isOffer is set to true in case of making an offer, otherwise set to false

   • Example.

     // make ordinary
     receipt = await marketplace.makeBid(auctionId, ZERO_ADDRESS, 0, false);
     
     // make offer
     receipt = await marketplace.makeBid(auctionId, ZERO_ADDRESS, 0, true);

4. Buyer can withdraw bid using Marketplace.withdrawBid(auctionId, bidId)

5. Seller can take offer using Markteplace.takeOffer(auctionId, bidId) before sale expiration

6. In case no offer is taken before expiration, marketplace owner stops the sale using Marketplace.stopAuction(auctionId)

7. The seller can settle the sale using Marketplace.settleAuction(auctionId, bidId, takeHighestBid)

   • Arguments.
     • auctionId is the ID of the sale to make bid or offer
     • bidId is the ID of the bid to take
     • takeHighestBid is set to true in case of taking the highest offer, otherwise set to false

8. In case of taking no offer, the seller can use Marketplace.withdrawAuction(auctionId) to withdraw the auction

9. When the sale expires for too long without further action, the marketplace owner can withdraw the sale using Marketplace.withdrawAuction(auctionId)

10. Failed buyers can withdraw all of his credits using Marketplace.withdrawAllCredits() to withdraw all cash transferred to the marketplace for making bids or offers

Ordinary working flow.

1. NFT author creates NFT (if not available) with ArtToken.create(initialOwner, initialSupply, uri, data)

   • Arguments.

     • initialOwner is the address of the initial owner, i.e. if initialOwner is not zero, then an amount of initialSupply of the NFT is minted and assigned to initialOwner
     • initialSupply is the amount of initially minted NFTs
     • uri is the URI of the NFT metadata
     • data is a 64-byte binary string. Should be zero binary string

   • Example.

     const ZERO_ADDRESS = web3.utils.padLeft(web3.utils.toHex(0), 40);
     const EMPTY_BYTES = web3.utils.padLeft(web3.utils.toHex(0), 64);
     const SAMPLE_URI = "https://web.skype.com/"
     
     receipt = await arttoken.create(
         ZERO_ADDRESS, 0, SAMPLE_URI, EMPTY_BYTES
     );

2. Seller create sale with Marketplace.createNftAuction(artTokenContractAddress, tokenIds, quantities, minPrice, buyNowPrice, bidIncreasePercentage)

   • Arguments.
     • artTokenContractAddress is the address of ArtToken contract
     • tokenIds is the IDs of the NFTs for sale
     • quantities is the quantities of each NFT for sale
     • minPrice is the reserve price for the auction
     • buyNowPrice is the buy-now price for the auction
     • bidIncreasePercentage is the minimum percentage increment allowed between successive bids

3. Buyer make a bid to the sale with Marketplace.makeBid(auctionId, nftRecipient, tokenAmount, isOffer)

   • Arguments.

     • auctionId is the ID of the sale to make bid or offer
     • nftRecipient is the address of the NFT recipient in case of successful purchase. Set to zero in case the buyer is the recipient
     • tokenAmount is the amount of WETH used for payment (should be non-zero for timed auction)
     • isOffer should be false

   • Example.

     receipt = await marketplace.makeBid(auctionId, ZERO_ADDRESS, 10, false);

4. Buyer can withdraw bid using Marketplace.withdrawBid(auctionId, bidId)

5. In case no offer is taken before expiration, marketplace owner stops the sale using Marketplace.stopAuction(auctionId)

6. The seller can settle the sale using Marketplace.settleAuction(auctionId, bidId, takeHighestBid)

   • Arguments.
     • auctionId is the ID of the sale to make bid or offer
     • bidId is the ID of the bid to take
     • takeHighestBid is set to true in case of taking the highest offer, otherwise set to false

7. In case of taking no offer, the seller can use Marketplace.withdrawAuction(auctionId) to withdraw the auction

8. When the sale expires for too long without further action, the marketplace owner can withdraw the sale using Marketplace.withdrawAuction(auctionId)

9. Failed buyers can withdraw all of his credits using Marketplace.withdrawAllCredits() to withdraw all cash transferred to the marketplace for making bids or offers

Ordinary working flow.

1. NFT author creates NFT (if not available) with ArtToken.create(initialOwner, initialSupply, uri, data)

   • Arguments.

     • initialOwner is the address of the initial owner, i.e. if initialOwner is not zero, then an amount of initialSupply of the NFT is minted and assigned to initialOwner
     • initialSupply is the amount of initially minted NFTs
     • uri is the URI of the NFT metadata
     • data is a 64-byte binary string. Should be zero binary string

   • Example.

     const ZERO_ADDRESS = web3.utils.padLeft(web3.utils.toHex(0), 40);
     const EMPTY_BYTES = web3.utils.padLeft(web3.utils.toHex(0), 64);
     const SAMPLE_URI = "https://web.skype.com/"
     
     receipt = await arttoken.create(
         ZERO_ADDRESS, 0, SAMPLE_URI, EMPTY_BYTES
     );

2. Seller create sale with Marketplace.createDecliningPriceSale(artTokenContractAddress, tokenIds, quantities, startPrice, endPrice, decrementDuration)

   • Arguments.
     • artTokenContractAddress is the address of ArtToken contract
     • tokenIds is the IDs of the NFTs for sale
     • quantities is the quantities of each NFT for sale
     • startPrice is the starting price of the sale
     • endPrice is the ending price of the sale
     • decrementDuration is the duration required for starting price to decrease down to ending price

3. Buyer make a bid to the sale with Marketplace.makeBid(auctionId, nftRecipient, tokenAmount, isOffer)

   • Arguments.

     • auctionId is the ID of the sale to make bid or offer
     • nftRecipient is the address of the NFT recipient in case of successful purchase. Set to zero in case the buyer is the recipient
     • tokenAmount is the amount of WETH used for payment (should be non-zero for declining-price sale)
     • isOffer should be false

   • Example.

     receipt = await marketplace.makeBid(auctionId, ZERO_ADDRESS, 10, false);

4. In case no offer is taken before expiration, marketplace owner stops the sale using Marketplace.stopAuction(auctionId)

5. In case of taking no offer, the seller can use Marketplace.withdrawAuction(auctionId) to withdraw the auction

6. When the sale expires for too long without further action, the marketplace owner can withdraw the sale using Marketplace.withdrawAuction(auctionId)

Display item activity. Each time a successful purchase is done, the following event is emitted

event NFTTransferredAndSellerPaid(
    uint256 auctionId, 
    uint256 bidId,
    uint256[] tokenIds,
    uint256[] quantities,
    uint256 price,
    address to,
    address from,
    uint256 blockTimestamp
);

Display token details. Use ArtToken.getTokenDetails(tokenId) to get

artTokenContractAddress, tokenId, tokenStandard, chainId, isMetadataFrozen

Environment setup.

# Install packages
npm install

# Install http-server
npm install --global http-server

Start the front-end. Under the project root, run the following command

npx http-server

The index.html file is given at frontend/ directory

• Minting
  • Mint ERC1155 NFT tokens with following format JPG, PNG, GIF, SVG, MP4, WEBM, MP3, WAV, OGG, GLB, GLTF. Max size 100MB
  • Function to for lazy minting
    • Solution: NFT creator must approve the marketplace for minting
  • NFTs transfer at sale creation and mint at payment
• Fixed-price sale
  • Fixed price NFT sold in eth (TESTED)
  • Reserve for a specfic buyer ie wallet address (TESTED)
  • Function to settle the sale after expiration (TESTED)
  • Function for buyer to make offer for NFT in eth or weth (TESTED)
    • This is when buyer does not want to buy at fixed price, and make their own offer to seller
    • This function has an expiration date and time for offer (BACKEND DO THIS)
  • Function to accept offer (TESTED)
    • Solution: Save as ordinary bid
• Timed auction sale, i.e. sell to the highest bidder
  • Timed auction NFT sold in weth (TESTED)
  • Reserve price option for auction (TESTED)
  • Maintain multiple offers at a time (TESTED)
    • Solution:
      • For each auction, maintain a list of bidders and bid prices
      • If the highest bidder withdraws the bid, he must pay for picking the new highest bidder
      • If the highest bidder wins the auction, other bids will be saved to failedTransferCredits
• Declining-price sale, i.e. allows the listing to reduce price until a buyer is found
  • Provide a function for backend to update buynow price
  • Declining-price sale NFT sold in weth (TESTED)
• Display function
  • Display item activity, i.e.
    • Item name, price, quantity
    • From username
    • To username
    • Time of transaction
  • Function to display token details, i.e.
    • Contract address
    • Token ID, Token Standard
    • Blockchain
    • If Metadata is editable
• Function to transfer to another wallet option (TESTED)