Idempotency

async function createSale(payload) {
  if (submitting) return; // çift tıklamayı engelle
  submitting = true;

  try {
    return await api.post("/v1/sales", payload);
  } finally {
    submitting = false;
  }
}

async function ensureAppointment(args) {
  const existing = await api.get("/v1/appointments", {
    params: {
      customer_id: args.customer_id,
      from: args.starts_at,
      to: args.starts_at,
    },
  });

  if (existing.data.length > 0) {
    return existing.data[0];
  }

  return api.post("/v1/appointments", args);
}

const localIdempotencyStore = new Map();

async function idempotentPost(uuid, url, body) {
  if (localIdempotencyStore.has(uuid)) {
    return localIdempotencyStore.get(uuid);
  }

  const pending = api.post(url, body);
  localIdempotencyStore.set(uuid, pending);

  try {
    return await pending;
  } catch (err) {
    localIdempotencyStore.delete(uuid); // hata durumunda yeniden denenebilsin
    throw err;
  }
}

try {
  return await api.post("/v1/sales", payload);
} catch (err) {
  if (err instanceof NetworkTimeout) {
    // Son 5 dakikada aynı müşteri/tutar kombinasyonuna sahip satış oluştu mu?
    const recent = await api.get("/v1/sales", {
      params: { customer_id, from: fiveMinutesAgo, to: now },
    });
    const maybe = recent.data.find(sameShape(payload));
    if (maybe) return maybe;
  }
  throw err;
}