import { PERMIT2_MAP } from '@prex0/prex-structs';
import { Address, erc20Abi, PublicActions } from 'viem';

export async function fetchBalanceCall(
  client: PublicActions,
  chainId: number,
  token: Address,
  user: Address
) {
  const results = await client.multicall({
    contracts: [
      {
        address: token,
        abi: erc20Abi,
        functionName: 'balanceOf',
        args: [user],
      },
      {
        address: token,
        abi: erc20Abi,
        functionName: 'allowance',
        args: [user, PERMIT2_MAP[chainId]],
      },
    ],
  });

  return {
    balance:
      results[0].status === 'success' ? BigInt(results[0].result) : undefined,
    allowance:
      results[1].status === 'success' ? BigInt(results[1].result) : undefined,
  };
}

export async function fetchBalanceBatch(
  client: PublicActions,
  tokens: Address[],
  user: Address
) {
  const results = await client.multicall({
    contracts: tokens.map((token) => ({
      address: token,
        abi: erc20Abi,
        functionName: 'balanceOf',
        args: [user],
      })),
  });

  return results.map((result, index) => ({
    token: tokens[index],
    balance: result.status === 'success' ? BigInt(result.result) : undefined,
    isSuccess: result.status === 'success',
  }));
}