Create Offer Manually Using TS interface

Steps to Create an Offer

1. Find Router address: First of all we should find current router address. In current version of contract only one router can exist But this might change in the future.

2. Define Offered and Requested Items: To create an offer, you first need to define the items being offered and requested. This involves specifying the type (NFT or Jetton), the amount, and the address of the assets involved.

   let offeredItems: Dictionary<number, SwapItem> = Dictionary.empty(); let requestedItems: Dictionary<number, SwapItem> = Dictionary.empty(); offeredItems.set(0, { $$type: 'SwapItem', amount: 1n, // NFT amount (always 1) type: 0n, // Type 0 for NFT address: nft0.address, }); offeredItems.set(1, { $$type: 'SwapItem', amount: jetton0Amount, // Jetton amount type: 1n, // Type 1 for Jetton address: jetton0.address, }); requestedItems.set(0, { $$type: 'SwapItem', amount: 1n, // NFT amount (always 1) type: 0n, // Type 0 for NFT address: nft1.address, });

3. Calculate the Minimum Value: Use the router to calculate the minimum value required to initiate the offer.

   const minValue = await router.getCalculateMinValue(offeredItems);

4. Find required queryId: In next step we should find new queryId so our new offer won't interfere with possibly deployed offer before For that we can loop over each query id to find not deployed offer contract. In most cases it would be 0n

   let queryId = 0n; let sellerSwap: OpenedContract<MultiSwap>; while(true){ sellerSwap = provider.open(await MultiSwap.fromInit( router.address, provider.sender().address!, queryId, true, // initiator is seller offeredItems requestedItems, )); // if not deployed if(!await provider.isContractDeployed(sellerSwap.address)){ break; } queryId = queryId + 1n; }

5. Deploy the Offer Contract: If the contract is not already deployed, send the necessary initialization transaction to deploy the offer contract.

   const deployResult = await router.send( provider.sender(), { value: minValue }, { $$type: 'InitMultiSwap', offered_items: offeredItems, requested_items: requestedItems, query_id: queryId, } as InitMultiSwap );

6. Wait for Deployment: After sending the deployment transaction, wait for the offer contract to be successfully deployed.

   await provider.waitForDeploy(sellerSwap.address, 50); console.log("Offer Deployed:"); console.log(sellerSwap.address.toString());

7. Send NFTs and Jettons to the Offer Contract: The next step is to send the offered NFTs and Jettons to the offer contract. This is done in one or more transactions, depending on the asset type. If TonConnect supports sending multiple messages in one transaction this could be done that way.

   Usually NFTs and Jettons take 0.07 ton to be transferred and also to trigger the swap contract Do not forget to specify response_destination in order to get some funds back forward_amount should be set to 0.02 ton

   console.log("sending NFTs and Jettons"); for (const [key, value] of offeredItems) { console.log(`Sending NO.${key}: ${value.amount} ${value.type == 0n ? "nft" : "jetton" } to ${sellerSwap.address.toString()}`); if (value.type == 0n) { // NFT case const nftItem = provider.open(await NftItem.fromAddress(value.address)); const deployResult = await nftItem.send( provider.sender(), { value: toNano('0.07'), }, { $$type: 'Transfer', query_id: 0n, new_owner: sellerSwap.address, response_destination: provider.sender().address, custom_payload: null, forward_amount: toNano('0.02'), forward_payload: beginCell().endCell().asSlice(), } as Transfer ); // Wait until the NFT is transferred (only because we're sending in 2 tx) while(true){ if ((await nftItem.getGetNftData()).owner_address.toString() == sellerSwap.address.toString()) { break; } await new Promise(r => setTimeout(r, 3000)); } } else { // Jetton case const jetton = provider.open(await TestJetton.fromAddress(value.address)); const jettonWalletAddress = await jetton.getGetWalletAddress(provider.sender().address!); const jettonWallet = provider.open(await JettonDefaultWallet.fromAddress(jettonWalletAddress)); const transferResult = await jettonWallet.send( provider.sender(), { value: toNano('0.07'), }, { $$type: 'TokenTransfer', query_id: 0n, amount: value.amount, sender: sellerSwap.address, response_destination: provider.sender().address, custom_payload: null, forward_ton_amount: toNano('0.02'), forward_payload: beginCell().endCell().asSlice(), } as TokenTransfer ); } }

8. Confirm the Transaction: After sending the NFTs and Jettons to the offer contract, the transaction is complete. The contract is now ready to be used, and you can confirm the assets have been successfully sent.

   Refer to constants to know at which state contract is in.

   In our case healthy response should be 2, that would mean that all Jettons and NFTs have been received and contract is now waiting to bond with buyer.

   let sellerData = await sellerSwap.getData(); let state = sellerData.state; if(state!=2n){ // StateReadyToSwap: Int = 2; throw "Contract is not waiting to bond" }

9. Failed Scenario: In case if seller won't be able to find a buyer or for some reason won't be able to provide all the assets, contract will expire in expiration_time_seconds timestamp

This is only possible on StateFailed or when contract has expired on state StateAwaitingFunds(1) | StateReadyToSwap(2) To retrieve lost assets, seller should message contract with "withdraw_seller" comment:

This guide covers the process of creating an offer manually using the TypeScript contract interface. Once the offer is created and assets are sent, the offer contract is deployed and the assets are locked in escrow, waiting for the buyer's response.