utils.ts

import { Contract } from '@ethersproject/contracts';
import { getAddress } from '@ethersproject/address';
import { AddressZero } from '@ethersproject/constants';
import { defaultAbiCoder } from '@ethersproject/abi';
import { JsonRpcSigner, Web3Provider } from '@ethersproject/providers';

// returns the checksummed address if the address is valid, otherwise returns false
export function isAddress(value: any): string | false {
  try {
    return getAddress(value);
  } catch {
    return false;
  }
}

// account is not optional
export function getSigner(library: Web3Provider, account: string): JsonRpcSigner {
  return library.getSigner(account).connectUnchecked();
}

// account is optional
export function getProviderOrSigner(
  library: Web3Provider,
  account?: string
): Web3Provider | JsonRpcSigner {
  return account ? getSigner(library, account) : library;
}

export function getContract(
  address: string,
  ABI: any,
  library: Web3Provider,
  account?: string
): Contract {
  if (!isAddress(address) || address === AddressZero) {
    throw Error(`Invalid 'address' parameter '${address}'.`);
  }

  return new Contract(address, ABI, getProviderOrSigner(library, account) as any);
}

export const bytesAreSafe = (address) => !address.match(/.{2}/g).find((byte) => byte === '5b');