import {utils, Contract, providers} from 'ethers';
import {AddressZero} from 'ethers/constants';
import ENS from '../../contracts/ENS.json';
import PublicResolver from '../../contracts/PublicResolver.json';
import {Nullable} from '../../core/types/common';

export const resolveName = async (
  provider: providers.Provider,
  ensAddress: string,
  ensName: string,
): Promise<Nullable<string>> => {
  const node = utils.namehash(ensName);
  const ensContract = new Contract(ensAddress, ENS.interface, provider);
  const resolverAddress = await ensContract.resolver(node);
  if (resolverAddress !== AddressZero) {
    const resolverContract = new Contract(resolverAddress, PublicResolver.interface, provider);
    const resolvedAddress = await resolverContract.addr(node);
    return resolvedAddress !== AddressZero ? resolvedAddress : null;
  } else {
    return null;
  }
};