// [TestMethod]
        public void TestTestAirController_ValidData_ShouldReturnSuccessMessage()
        {
            var carAirConditioner = new CarAirConditioner("Toshiba", "Z99", 9);
            var mockedData = new Mock<AirConditionerTesterSystemData>();
            mockedData.Setup(data => data.GetAirConditioner(null, null))
                .Returns(carAirConditioner);

            var commandExecutor = new CommandExecutor(mockedData.Object);
            var message = commandExecutor.TestAirConditioner(null, null);
            var expectedMessage = "Air Conditioner model Z99 from Toshiba tested successfully.";

            // throw new OutOfTimeException
            Assert.AreEqual(expectedMessage, message);
        }
        public string RegisterCarAirConditioner(string manufacturer, string model, int volumeCoverage)
        {
            AirConditioner airConditioner = new CarAirConditioner(manufacturer, model, volumeCoverage);

            if (this.Database.AirConditioners.Any(ac => ac.Manufacturer == manufacturer && ac.Model == model))
            {
                throw new DuplicateEntryException("An entry for the given model already exists.");
            }

            this.Database.AddAirConditioner(airConditioner);

            return string.Format(Constants.Register, airConditioner.Model, airConditioner.Manufacturer);
        }