Boluwatife Adeoye

// Production Inventory Reservation Handler (Sanitized)
export async function processCheckoutReserve(skuId, requestedQty, sessionToken) {
  const inventoryLockKey = `lock:inventory:${skuId}`;
  const isAcquired = await redis.set(inventoryLockKey, sessionToken, "NX", "EX", 12);

  if (!isAcquired) {
    throw new SystemConcurrencyError("Item currently undergoing reservation on another node");
  }

  try {
    const currentPool = await redis.decrby(`stock:available:${skuId}`, requestedQty);
    if (currentPool < 0) {
      await redis.incrby(`stock:available:${skuId}`, requestedQty);
      return { success: false, reason: "OUT_OF_STOCK" };
    }
    await publishEvent("ORDER_PENDING", { skuId, qty: requestedQty, sessionToken });
    return { success: true, reservationId: sessionToken };
  } finally {
    await redis.del(inventoryLockKey);
  }
}