@avalanche-sdk/interchain/src/ictt/utils/approveToken.ts

Interchain package for handling ICM/ICTT messages

import { createPublicClient, http, WalletClient } from "viem";
import { erc20ABI } from "../../abis/erc20ABI";
import { ChainConfig } from "../../chains/types/chainConfig";
import { getERC20TokenInfo } from "./getERC20TokenInfo";

export async function approveToken(params: {
  walletClient: WalletClient;
  chain: ChainConfig;
  spenderAddress: `0x${string}`;
  tokenAddress: `0x${string}`;
  amountInBaseUnit: number;
}) {
  const publicClient = createPublicClient({
    chain: params.chain,
    transport: http(),
  });

  const { tokenDecimals } = await getERC20TokenInfo(
    params.chain,
    params.tokenAddress
  );
  const amountInWei =
    BigInt(params.amountInBaseUnit) * BigInt(10 ** tokenDecimals);
  const approveTxHash = await params.walletClient.writeContract({
    address: params.tokenAddress,
    abi: erc20ABI.abi,
    functionName: "approve",
    args: [params.spenderAddress, amountInWei],
    chain: params.chain,
    account: params.walletClient.account ?? null,
  });

  const receipt = await publicClient.waitForTransactionReceipt({
    hash: approveTxHash,
  });
  if (receipt.status === "success") {
    return { txHash: approveTxHash };
  } else {
    throw new Error("Failed to approve token.", { cause: receipt });
  }
}