/// <summary>
/// Get a resulting loan object
/// </summary>
/// <param name="concreteLoanInput"></param>
/// <returns></returns>
private ConcreteLoanOutput GetLoanOutput(ConcreteLoanInput concreteLoanInput)
{
var loanAmount = Convert.ToDouble(concreteLoanInput.Amount - concreteLoanInput.Downpayment);
var rateOfInterest = concreteLoanInput.Interest / 1200;
var numberOfPayments = concreteLoanInput.Term * 12;
var monthlyPayment = (rateOfInterest * loanAmount) / (1 - Math.Pow(1 + rateOfInterest, numberOfPayments * -1));
var totalPayment = monthlyPayment * numberOfPayments;
var totalInterest = totalPayment - loanAmount;
return(new ConcreteLoanOutput()
{
MonthlyPayment = decimal.Round(Convert.ToDecimal(monthlyPayment), 2),
TotalInterest = decimal.Round(Convert.ToDecimal(totalInterest), 2),
TotalPayment = decimal.Round(Convert.ToDecimal(totalPayment), 2)
});
}
/// <summary> /// sanity check /// </summary> /// <param name="concreteCalcInput"></param> /// <returns></returns> private bool IsDataCorrect(ConcreteLoanInput concreteCalcInput) => concreteCalcInput.Amount > 0 && concreteCalcInput.Downpayment >= 0 && concreteCalcInput.Interest > 0 && concreteCalcInput.Term > 0;