Methods Overview

1. makeOffer – Lock your sell-asset into escrow and publish an OTC offer to receive your desired buy-asset.

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1. makeOffer

function makeOffer(
    Asset calldata       depositAsset,
    Asset calldata       withdrawalAsset,
    OfferStruct calldata offer
) external;

What it does: You deposit your chosen asset (depositAsset) into escrow and create an offer for others to swap their asset (withdrawalAsset) with you. On success, it emits a CreatedOffer event including your new offerId.

Tip: The deposit is locked immediately. Use the returned offerId to track or cancel your offer later.

Parameters

Asset Structure

interface Asset {
  assetType:     AssetType;    // ERC20=1, ERC721=2, ERC1155=3
  assetAddress:  string;       // token or NFT contract address
  amount:        BigNumber;    // qty for ERC20/ERC1155; 1 for ERC721
  tokenId:       BigNumber;    // token ID for ERC721/ERC1155; 0 for ERC20
  assetPrice:    AssetPrice;   // only for DynamicPricing
}

interface AssetPrice {
  priceFeedAddress:  string;    // e.g., Chainlink feed
  offerMaximumPrice: BigNumber; // max rate (in withdrawalAsset decimals)
  offerMinimumPrice: BigNumber; // min rate
}

OfferStruct Structure

interface OfferStruct {
  takingOfferType:       TakingOfferType;    // PartialOffer=1 or BlockOffer=2
  offerPrice:            OfferPrice;         // Fixed or Dynamic pricing
  specialAddresses:      string[];           // restrict to these takers (empty = public)
  authorizationAddresses:string[];           // same as above
  expiryTimestamp:       number;             // when offer expires (unix sec)
  timelockPeriod:        number;             // seconds before it can be taken
  terms:                 string;             // URL/IPFS to off-chain terms
  commsLink:             string;             // chat/email link
}

interface OfferPrice {
  offerPricingType: OfferPricingType; // FixedPricing=1 or DynamicPricing=2
  unitPrice:        BigNumber;        // price per 1 depositAsset (Fixed)
  percentage:       BigNumber;        // adjust unitPrice by this %
  percentageType:   PercentageType;   // Plus=1 or Minus=2
}

---

Event Emitted

event CreatedOffer(
  address indexed maker,
  uint256 indexed offerId,
  DotcOffer dotcOffer
);

• maker: your address
• offerId: unique ID of your new offer
• dotcOffer: the on-chain record of all your offer details

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Possible Errors

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Usage Tutorial

Example in TypeScript & Ethers.js Copy-paste into makeOffer.ts, install ethers, then npx ts-node makeOffer.ts.

Prerequisites

• Node.js ≥16 & npm/yarn
• Netowrk RPC endpoint (e.g. https://polygon-rpc.com/ for polygon)
• Wallet with enough depositAsset tokens approved

1. Setup & Connect

import { ethers } from "ethers";

const RPC_URL          = "https://polygon-rpc.com"; // use RPC accroding to your network
const PRIVATE_KEY      = "YOUR_PRIVATE_KEY";
const DOTC_ADDRESS     = ethers.getAddress("0x22593b8749A4e4854C449c30054Bb4D896374fa1");

const provider = new ethers.providers.JsonRpcProvider(RPC_URL);
const wallet   = new ethers.Wallet(PRIVATE_KEY, provider);

// Minimal ABI for makeOffer + event
const ABI = [
  "function makeOffer((uint8,address,uint256,uint256,(address,uint256,uint256)),(uint8,address,uint256,uint256,(address,uint256,uint256)),(uint8,(uint8,uint256,uint256,uint8),address[],address[],uint256,uint256,string,string))",
  "event CreatedOffer(address indexed maker, uint256 indexed offerId, tuple(address,uint8,(uint8,address,uint256,uint256),uint256,uint256,string,string) dotcOffer)"
];

const dotc = new ethers.Contract(DOTC_ADDRESS, ABI, wallet);

2. Define Your Offer

// Replace TOKEN_A and TOKEN_B with actual addresses
const TOKEN_A = "0xYourTokenA";
const TOKEN_B = "0xYourTokenB";

// 2a) Deposit: 100 of TOKEN_A (18 decimals)
const depositAsset = {
  assetType:    1, // ERC20
  assetAddress: TOKEN_A,
  amount:       ethers.utils.parseUnits("100.0", 18),
  tokenId:      0,
  assetPrice: {
    priceFeedAddress:  ethers.constants.AddressZero,
    offerMaximumPrice: ethers.constants.Zero,
    offerMinimumPrice: ethers.constants.Zero,
  },
};

// 2b) Withdrawal: 200 of TOKEN_B (6 decimals)
const withdrawalAsset = {
  assetType:    1,
  assetAddress: TOKEN_B,
  amount:       ethers.utils.parseUnits("200.0", 6),
  tokenId:      0,
  assetPrice: {
    priceFeedAddress:  ethers.constants.AddressZero,
    offerMaximumPrice: ethers.constants.Zero,
    offerMinimumPrice: ethers.constants.Zero,
  },
};

// 2c) Terms: FixedPricing 2 TOKEN_B per 1 TOKEN_A
const offer = {
  takingOfferType:        1, // PartialOffer
  offerPrice: {
    offerPricingType:     1, // FixedPricing
    unitPrice:            ethers.utils.parseUnits("2.0", 6),
    percentage:           ethers.constants.Zero,
    percentageType:       0, // NoType
  },
  specialAddresses:       [],
  authorizationAddresses: [],
  expiryTimestamp:        Math.floor(Date.now()/1000) + 3600, // +1h
  timelockPeriod:         0,                                
  terms:                  "",
  commsLink:              ""
};

3. Submit & Listen

async function run() {
  console.log("📡 Submitting makeOffer...");
  const tx = await dotc.makeOffer(depositAsset, withdrawalAsset, offer);
  console.log("🔗 Tx hash:", tx.hash);
  const receipt = await tx.wait();

  for (const ev of receipt.events ?? []) {
    if (ev.event === "CreatedOffer") {
      console.log("✅ Offer created!", {
        maker:   ev.args![0],
        offerId: ev.args![1].toString()
      });
    }
  }
}

run().catch(console.error);

4. Run It

npm install ethers
npx ts-node makeOffer.ts