private CoffeeDeviceState GetCurrentUserCoffeeDeviceState(string appUserId)
        {
            CoffeeDevice coffeeDevice = _coffeeRepository.GetCoffeeDeviceByUserId(appUserId);

            if (coffeeDevice != null)
            {
                return(CoffeDeviceToCoffeeSeviceState(coffeeDevice));
            }
            else
            {
                return(null);
            }
        }