public IActionResult Index(HeatCostViewModel model)
        {
            if (!ModelState.IsValid)
            {
                return(View(model));
            }

            var cost        = HeatCalculatorService.CalculateCost(model.SizeInSquareFeet, ClimateZone.FromValue(model.ClimateZoneId).Code);
            var resultModel = new HeatCostResultViewModel()
            {
                ClimateZone      = ClimateZone.FromValue(model.ClimateZoneId).Name,
                SizeInSquareFeet = model.SizeInSquareFeet,
                Cost             = cost
            };

            return(View("Result", resultModel));
        }
        public void ReturnsXGiven1500AndMild(int size, string climate, decimal expectedResult)
        {
            var result = HeatCalculatorService.CalculateCost(size, climate);

            Assert.Equal(expectedResult, result);
        }