public decimal Calculate(decimal amount, ITaxSettings settings)
{
//we expect a table of values in the format: from:to
//the from starts from 0 and extends to the max value (100000000)
decimal currentMin = 0;
decimal currentTax = 0;
foreach (var(name, value) in settings.GetList())
{
if (amount < currentMin)
{
break;
}
try
{
var upperBound = Convert.ToDecimal(name);
var taxPerc = Convert.ToDecimal(value);
var bracketAmount = Math.Min(amount, upperBound) - currentMin;
var taxAmount = bracketAmount * taxPerc;
currentTax += taxAmount;
currentMin = upperBound;
}
catch
{
// ignored
}
}
return(currentTax);
}
public void TestIterator()
{
var results = new Dictionary <string, string>();
foreach (var item in _settings.GetList())
{
results[item.name] = item.value;
}
Assert.AreEqual(results.Count, _settings.GetCount());
foreach (var key in results.Keys.Where(key => results[key] != _settings.GetValue <string>(key)))
{
Assert.Fail("Value doesn't match");
}
}