Prepaid credits

import {
  Billing,
  Credits,
  Offer,
  Purchase,
  consumeCredits,
  createCheckout,
  getCreditBalance,
  getCreditHistory,
  processPaymentNotification,
  registerOffers,
  releaseCredits,
  reserveCredits,
} from "@byfungsi/sapa";

const credits = yield * Credits.pack({ unit: "ai.credit", quantity: 1_000n });
const creditPurchase =
  yield *
  Purchase.parse({
    key: "credits.balance",
    revision: 1,
    provides: [credits],
  });
const creditBilling =
  yield *
  Billing.oneTime({
    price: { currency: "IDR", amount: 100_000n },
  });
const creditPack =
  yield *
  Offer.parse({
    key: "credits.pack",
    revision: 1,
    purchase: creditPurchase,
    billing: creditBilling,
  });

yield * registerOffers([creditPack]);
yield *
  createCheckout({
    type: "offer",
    offerKey: creditPack.key,
    offerRevision: creditPack.revision,
    quantity: null,
    provider: "midtrans",
    customer,
    successUrl,
    cancelUrl,
    clientIp: null,
    idempotencyKey: "credit-pack-42",
  });
yield *
  processPaymentNotification({
    provider: "midtrans",
    payload: rawProviderPayload,
  });

const query = { customerId: "customer-42", unit: "ai.credit" };
const before = yield * getCreditBalance(query);
const reservation =
  yield *
  reserveCredits({
    ...query,
    quantity: 10n,
    idempotencyKey: "generation-job-88",
  });

// After the external work is known to have consumed the units:
yield * consumeCredits({ reservationId: reservation.id });

// For a different reservation whose work definitely did not run:
const unused =
  yield *
  reserveCredits({
    ...query,
    quantity: 5n,
    idempotencyKey: "generation-job-89",
  });
yield * releaseCredits({ reservationId: unused.id });

const after = yield * getCreditBalance(query);
const movements = yield * getCreditHistory(query);

Consume and release are alternative terminal outcomes for one reservation. Never release in a generic cleanup block when an external result is uncertain; reconcile first. Reservations expire after the installation’s bounded window, and all quantities are exact units—not currency.