#!/usr/bin/env node
/**
 * Preview digest for off-chain attestation signing (fiat / XAU custodian flow).
 * Uses keccak256(abi.encode(lineId, R, nonce, validUntil, evidenceKind)) — align with ops before HSM.
 * Usage: node omnl-attestation-payload.mjs <lineId0x> <R> <nonce> <validUntil> <evidenceKind>
 */
import { keccak256, AbiCoder } from 'ethers';

const [, , lineId, R, nonce, validUntil, evidenceKind] = process.argv;
if (!evidenceKind) {
  console.error(
    'Usage: omnl-attestation-payload.mjs <lineId0x> <R> <nonce> <validUntil> <evidenceKind>'
  );
  process.exit(1);
}
const coder = AbiCoder.defaultAbiCoder();
const encoded = coder.encode(
  ['bytes32', 'uint256', 'uint256', 'uint256', 'string'],
  [lineId, BigInt(R), BigInt(nonce), BigInt(validUntil), evidenceKind]
);
const digest = keccak256(encoded);
process.stdout.write(JSON.stringify({ digest, encoded }, null, 2) + '\n');