public CostCommand(ITariffSource source)
{
Spec = CommandSpec.Named(
"cost",
new[] { "POWER_USAGE_KWH", "GAS_USAGE_KWH" },
ctx =>
{
// model 0's explicitly as no fuel supply for that type
var p = ctx.GetRequiredDecimal("POWER_USAGE_KWH");
var powerKwh = p == 0 ? new Kwh <Power>?() : new Kwh <Power>(p);
var g = ctx.GetRequiredDecimal("GAS_USAGE_KWH");
var gasKwh = g == 0 ? new Kwh <Gas>?() : new Kwh <Gas>(g);
// calculate the costs and output
foreach (var line in FuelCalculator
.CostsPerTariff(source.GetAll(), powerKwh, gasKwh)
.Select(cost => $"{cost.Tariff.Name} {cost.Total.PostTax:F2}"))
{
ctx.Output.WriteLine(line);
}
return(Commands.Ok());
});
}
public UsageCommand(ITariffSource source)
{
Spec = CommandSpec.Named(
"usage",
new[] { "TARIFF_NAME", "FUEL_TYPE", "TARGET_MONTHLY_SPEND" },
ctx =>
{
var tariffName = ctx.GetRequiredString("TARIFF_NAME");
var fuelType = ctx.GetRequiredEnum <FuelType>("FUEL_TYPE");
var monthlyBudget = TaxedValue.FromPostTaxValue(
ctx.GetRequiredDecimal("TARGET_MONTHLY_SPEND"),
TaxHelper.RemoveTax);
if (!source.TryGet(tariffName, out var tariff))
{
return(Commands.Error($"The specified tariff doesn't exist '{tariffName}'."));
}
// c# has no proper pattern matching, so I've run out of functional luck here, apologies for the switch statement...
switch (fuelType)
{
case FuelType.Gas:
if (!tariff.GasRate.HasValue)
{
return(Commands.Error($"Tariff '{tariff.Name}' does not include {FuelType.Gas}."));
}
ctx.Output.WriteLine(
FuelCalculator.AnnualGasUsage(tariff, monthlyBudget).GetValueOrDefault().Value); // just output 0 if tariff doesn't include fuel type
break;
case FuelType.Power:
if (!tariff.PowerRate.HasValue)
{
return(Commands.Error($"Tariff '{tariff.Name}' does not include {FuelType.Power}."));
}
ctx.Output.WriteLine(
FuelCalculator.AnnualPowerUsage(tariff, monthlyBudget).GetValueOrDefault().Value);
break;
default:
return(Commands.Error($"Unsupported fuel type : {fuelType}"));
}
return(Commands.Ok());
});
}
