argus/test/chipnet-escrow-refund.mjs

// LIVE chipnet test: pay from an exchange, fail to sign, get refunded.
//
// THE SCENARIO
//   1. The buyer starts a purchase. We generate their destination wallet in the
//      browser there and then, so the destination is always a key they hold.
//   2. They pay from somewhere else entirely — an exchange withdrawal, which
//      cannot sign for anything and cannot receive a CashToken.
//   3. Before minting, they must sign a challenge with the destination key,
//      proving they still have the wallet we gave them.
//   4. They never sign — the tab was closed, the phrase was never written down.
//   5. The quote expires and the escrow refunds the payment.
//
// WHAT THIS MUST PROVE
//   - `magicworld.x` is NEVER minted. An irrevocable certificate locked to a key
//     nobody holds is the worst outcome in the whole product, worse than a failed
//     sale, and it is silent.
//   - The money goes back to whoever actually paid, recovered from the payment
//     transaction rather than from anything the buyer typed.
//   - A signature from the wrong key does not open the gate.
//
// Run: node test/chipnet-escrow-refund.mjs

import WebSocket from "ws";
import { readFileSync } from "node:fs";
import { deriveHdPrivateNodeFromSeed, deriveSeedFromBip39Mnemonic } from "@bitauth/libauth";

import { BuiltInWallet } from "../src/lib/wallet-web.js";
import { connect, checkAvailability, getBalance } from "../src/lib/registrar.js";
import { loadWallet } from "../src/lib/wallet.js";
import { payerAddressOf, addressToLockingBytecode, broadcast, getUtxos } from "../src/lib/chain.js";
import { signTransaction } from "../src/lib/sign-tx.js";
import { controlChallenge, verifyControl, signMessageBip137 } from "../src/lib/sign-message.js";
import {
  quotePrice, bip21, createOrder, depositAddressAt, depositKeyAt,
  checkPayment, buildRefundTx, ORDER_STATUS,
} from "../src/lib/orders.js";
import { REGISTRAR } from "../src/registrar-config.js";

const NAME = "magicworld.x";

let failures = 0;
const check = (ok, label, detail = "") => {
  console.log(`   ${ok ? "PASS" : "FAIL"}  ${label}${detail ? "  — " + detail : ""}`);
  if (!ok) failures++;
};
const step = (n, s) => console.log(`\n─── ${n}. ${s} ${"─".repeat(Math.max(0, 54 - s.length))}`);
const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

let client;
try {
  client = await connect({ WebSocket });
} catch (e) {
  console.error(`\ncannot reach the chain — the test cannot run.\n${e.message}\n`);
  process.exit(2);
}

try {
  console.log(`Escrow refund on failure-to-sign — live on ${REGISTRAR.network}`);

  // ── 1. destination wallet, created for the buyer during checkout ─────────
  step(1, "Generate the buyer's destination wallet in-browser");
  const buyer = await BuiltInWallet.create();
  console.log(`   destination   : ${buyer.address}`);
  check(
    (await getBalance(client, buyer.watchedAddresses)).sats === 0n,
    "brand-new wallet, usable immediately — the buyer could fund it right now",
  );

  const avail = await checkAvailability(client, NAME);
  check(avail.available, `${NAME} is available before we start`);
  if (!avail.available) throw new Error(`${NAME} is already registered — pick another name for this test`);

  // ── 2. quote ─────────────────────────────────────────────────────────────
  step(2, "Quote the name and open the escrow");
  const store = JSON.parse(readFileSync(new URL("../wallets.json", import.meta.url), "utf8"));
  const root = deriveHdPrivateNodeFromSeed(await deriveSeedFromBip39Mnemonic(store.main.seed));
  const orderIndex = Math.floor(Math.random() * 1_000_000);
  const deposit = depositAddressAt(orderIndex, { hdNode: root });
  const priceSats = quotePrice({ serviceFeeSats: REGISTRAR.serviceFee.sats });

  const order = createOrder({
    index: orderIndex, name: NAME, buyerAddress: buyer.address,
    priceSats, depositAddress: deposit, now: Date.now(),
  });
  console.log(`   escrow addr   : ${deposit}`);
  console.log(`   price         : ${priceSats} sat`);
  console.log(`   QR            : ${bip21({ address: deposit, satoshis: priceSats, message: `Register ${NAME}` })}`);
  check(order.status === ORDER_STATUS.quoted, "order starts quoted");

  // ── 3. payment from an "exchange" ────────────────────────────────────────
  step(3, "Buyer pays from an exchange (cannot sign, cannot hold tokens)");
  const exchange = await loadWallet("main");
  const payment = await exchange.send([{ cashaddr: deposit, value: Number(priceSats), unit: "sat" }]);
  console.log(`   payment txid  : ${payment.txId}`);

  let paid = null;
  for (let i = 0; i < 25; i++) {
    const p = await checkPayment(client, order);
    if (p.paid) { paid = p; break; }
    process.stdout.write(`   watching escrow… ${i + 1}/25\r`);
    await sleep(3000);
  }
  console.log("");
  check(!!paid, "escrow received the payment", paid ? `${paid.receivedSats} sat` : "nothing");
  order.status = ORDER_STATUS.awaitingSignature;

  // ── 4. the gate ──────────────────────────────────────────────────────────
  step(4, "Gate the mint on proof the buyer still holds the destination key");
  const challenge = controlChallenge({ name: NAME, destination: buyer.address, orderIndex });
  console.log(`   challenge     : ${challenge}`);

  // The buyer could sign — the key is right there in their browser. Prove the
  // gate opens for the right key, so a later failure is meaningful.
  const goodSig = signMessageBip137(challenge, buyer.receive[0].privateKey);
  check(
    verifyControl({ message: challenge, signature: goodSig, expectedAddress: buyer.address }).ok,
    "the real destination key opens the gate",
  );

  // Someone else's key must not.
  const impostor = await BuiltInWallet.create();
  const badSig = signMessageBip137(challenge, impostor.receive[0].privateKey);
  const badResult = verifyControl({ message: challenge, signature: badSig, expectedAddress: buyer.address });
  check(!badResult.ok, "a different key does NOT open the gate", badResult.reason);

  // Neither does a signature for a different order.
  const replay = signMessageBip137(
    controlChallenge({ name: NAME, destination: buyer.address, orderIndex: orderIndex + 1 }),
    buyer.receive[0].privateKey,
  );
  check(
    !verifyControl({ message: challenge, signature: replay, expectedAddress: buyer.address }).ok,
    "a signature from another order cannot be replayed",
  );

  // ── 5. …but this buyer never signs ───────────────────────────────────────
  step(5, "The buyer never signs — tab closed, phrase never saved");
  const submitted = null; // nothing arrives before the deadline
  const gateOpen = submitted
    ? verifyControl({ message: challenge, signature: submitted, expectedAddress: buyer.address }).ok
    : false;
  check(!gateOpen, "the mint gate stays shut");

  // ── 6. expire and refund ─────────────────────────────────────────────────
  step(6, "Quote expires — escrow refunds the payer");
  order.expiresAt = Date.now() - 1; // deadline reached
  check(Date.now() > order.expiresAt, "quote has expired");
  order.status = ORDER_STATUS.refunding;

  // Where does the money go? Read it off the payment, not off anything typed.
  const payerAddress = await payerAddressOf(client, payment.txId);
  console.log(`   payer (recovered from the payment): ${payerAddress}`);
  check(!!payerAddress, "payer address recovered from the payment transaction");
  check(
    payerAddress === exchange.cashaddr,
    "recovered address matches the actual sender",
    `expected ${exchange.cashaddr}`,
  );

  const depositKey = depositKeyAt(orderIndex, root);
  const escrowUtxos = await getUtxos(client, deposit);
  const refund = buildRefundTx({
    utxos: escrowUtxos,
    toAddress: payerAddress,
    addressToLockingBytecode,
  });
  const signedRefund = signTransaction(refund.transaction, refund.sourceOutputs, (h) =>
    h === Buffer.from(depositKey.lockingBytecode).toString("hex")
      ? { privateKey: depositKey.privateKey, publicKey: depositKey.publicKey }
      : null,
  );
  const refundTxid = await broadcast(client, signedRefund.hex);
  order.status = ORDER_STATUS.refunded;
  console.log(`   refund txid   : ${refundTxid}`);
  console.log(`   refunded      : ${refund.costs.refundedSats} sat (fee ${refund.costs.chainFeeSats})`);

  let emptied = false;
  for (let i = 0; i < 25; i++) {
    const p = await checkPayment(client, order);
    if (p.receivedSats === 0n) { emptied = true; break; }
    process.stdout.write(`   waiting for the escrow to drain… ${i + 1}/25\r`);
    await sleep(3000);
  }
  console.log("");
  check(emptied, "escrow is empty — the money left");
  check(
    refund.costs.refundedSats > priceSats - 1000n,
    "buyer got back essentially everything",
    `${refund.costs.refundedSats} of ${priceSats} sat`,
  );

  // ── 7. the thing that must never have happened ───────────────────────────
  step(7, "Verify the name was never minted");
  const after = await checkAvailability(client, NAME);
  check(after.available, `${NAME} is STILL unregistered — no certificate was created`);
  check(
    (await getBalance(client, buyer.watchedAddresses)).certificates.length === 0,
    "the buyer's wallet holds no certificate",
  );

  step("=", failures === 0 ? "RESULT: ALL CHECKS PASSED" : `RESULT: ${failures} CHECK(S) FAILED`);
  console.log(`   unsigned purchase refunded to ${payerAddress}`);
  console.log(`   ${NAME} never left the shelf`);
} finally {
  client.close();
}

process.exit(failures === 0 ? 0 : 1);