Withdraw USDC from HyperCore to EVM chains

/**
 * Script: Withdraw USDC from HyperCore to EVM chain
 * - Signs EIP-712 sendToEvmWithData action
 * - Submits to Hyperliquid /exchange API
 */

import { Wallet, Signature } from "ethers";

// -------- Configuration --------
const config = {
  privateKey: process.env.PRIVATE_KEY as string,

  // Transfer parameters
  amount: process.env.AMOUNT || "10", // 10 USDC
  sourceDex: process.env.SOURCE_DEX || "", // "" for perp, "spot" for spot

  // Destination parameters
  destinationRecipient: process.env.DESTINATION_RECIPIENT as string,
  destinationChainId: Number(process.env.DESTINATION_CHAIN_ID || 3), // 3 = Arbitrum
  addressEncoding: process.env.ADDRESS_ENCODING || "hex",
  gasLimit: Number(process.env.GAS_LIMIT || 200000),
  data: process.env.DATA || "0x", // "0x" enables automatic forwarding

  // Hyperliquid environment
  isMainnet:
    String(process.env.HL_IS_MAINNET || "false").toLowerCase() === "true",
  signatureChainId: "0xa4b1", // Destination chain's EVM chain ID (hex) for EIP-712 signing
};

// -------- Main Function --------
async function main() {
  // Validate required parameters
  if (!config.privateKey) {
    throw new Error("Set PRIVATE_KEY");
  }
  if (!config.destinationRecipient) {
    throw new Error("Set DESTINATION_RECIPIENT");
  }

  const apiUrl = config.isMainnet
    ? "https://api.hyperliquid.xyz"
    : "https://api.hyperliquid-testnet.xyz";
  const hyperliquidChain = config.isMainnet ? "Mainnet" : "Testnet";
  const chainId = parseInt(config.signatureChainId, 16);
  const timestamp = Date.now();

  console.log("Withdrawing from HyperCore:", hyperliquidChain);
  console.log("Source balance:", config.sourceDex || "perp");
  console.log("Amount (USDC):", config.amount);
  console.log("Destination recipient:", config.destinationRecipient);
  console.log("Destination chain ID:", config.destinationChainId);
  console.log("Gas limit:", config.gasLimit);

  // EIP-712 Domain
  const domain = {
    name: "HyperliquidSignTransaction",
    version: "1",
    chainId,
    verifyingContract: "0x0000000000000000000000000000000000000000",
  };

  // EIP-712 Types
  const types = {
    "HyperliquidTransaction:SendToEvmWithData": [
      { name: "hyperliquidChain", type: "string" },
      { name: "token", type: "string" },
      { name: "amount", type: "string" },
      { name: "sourceDex", type: "string" },
      { name: "destinationRecipient", type: "string" },
      { name: "addressEncoding", type: "string" },
      { name: "destinationChainId", type: "uint32" },
      { name: "gasLimit", type: "uint64" },
      { name: "data", type: "bytes" },
      { name: "nonce", type: "uint64" },
    ],
  };

  // Message to sign
  const message = {
    hyperliquidChain,
    token: "USDC",
    amount: config.amount,
    sourceDex: config.sourceDex,
    destinationRecipient: config.destinationRecipient,
    addressEncoding: config.addressEncoding,
    destinationChainId: config.destinationChainId,
    gasLimit: BigInt(config.gasLimit),
    data: config.data,
    nonce: BigInt(timestamp),
  };

  // Sign the message using EIP-712
  const wallet = new Wallet(config.privateKey);
  const sigHex = await wallet.signTypedData(domain, types, message);
  const sig = Signature.from(sigHex);

  // Build action payload
  const action = {
    type: "sendToEvmWithData",
    hyperliquidChain,
    signatureChainId: config.signatureChainId,
    token: "USDC",
    amount: config.amount,
    sourceDex: config.sourceDex,
    destinationRecipient: config.destinationRecipient,
    addressEncoding: config.addressEncoding,
    destinationChainId: config.destinationChainId,
    gasLimit: config.gasLimit,
    data: config.data,
    nonce: timestamp,
  };

  // Submit to Hyperliquid exchange API
  const response = await fetch(`${apiUrl}/exchange`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({
      action,
      nonce: timestamp,
      signature: { r: sig.r, s: sig.s, v: sig.v },
    }),
  });

  const result = await response.json();

  console.log("\nStatus:", response.status);
  console.log("Response:", JSON.stringify(result, null, 2));

  if (response.status === 200 && result.status === "ok") {
    console.log("\nWithdrawal initiated successfully");
  } else {
    throw new Error(`Withdrawal failed: ${JSON.stringify(result)}`);
  }
}

// Run
main().catch((error) => {
  console.error("Error:", error.message);
  process.exit(1);
});