How to: Add Arc to a Wallet

const arcTestnet = {
  chainId: "0x4CF4B2",
  chainName: "Arc Testnet",
  nativeCurrency: {
    name: "USDC",
    symbol: "USDC",
    decimals: 6,
  },
  rpcUrls: ["https://rpc.testnet.arc.network"],
  blockExplorerUrls: ["https://testnet.arcscan.app"],
};

const balanceWei = await provider.getBalance(address); // 18-decimal BigInt

const DECIMALS_OFFSET = 12n;
const displayAmount = balanceWei / 10n ** DECIMALS_OFFSET; // 6-decimal value
const formatted = (Number(displayAmount) / 1e6).toFixed(6); // e.g. "1.500000"

event Transfer(address indexed from, address indexed to, uint256 value);

const USDC_CONTRACT = "0x3600000000000000000000000000000000000000";
const TRANSFER_TOPIC =
  "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef";

// Filter for transfers involving the user (as sender or receiver)
const paddedAddress = "0x" + address.slice(2).padStart(64, "0");

const logs = await provider.getLogs({
  address: USDC_CONTRACT,
  topics: [TRANSFER_TOPIC, [paddedAddress, null], [null, paddedAddress]],
  fromBlock: "earliest",
  toBlock: "latest",
});

import { parseAbi, decodeEventLog } from "viem";

const abi = parseAbi([
  "event Transfer(address indexed from, address indexed to, uint256 value)",
]);

for (const log of logs) {
  const { args } = decodeEventLog({ abi, data: log.data, topics: log.topics });
  const amount = Number(args.value) / 1e6; // Human-readable USDC
}

const gasPrice = await provider.getGasPrice(); // Returns USDC wei (18 decimals)
const gasLimit = await provider.estimateGas(tx);

const feeWei = gasPrice * gasLimit; // Total fee in 18-decimal USDC wei
const feeUsdc = Number(feeWei) / 1e18; // Human-readable USDC