private decimal ApplyPayments(int startYear, int startMonth, int startDay, decimal presentValue, decimal interestRate, LoanPayments payments,
ref LoanStatistics stats)
{
var currentDate = new DateTime(startYear, startMonth, startDay);
var orderedList = payments.Values.OrderBy(x => x.Year).ThenBy(x => x.Month).ThenBy(x => x.Day);
foreach (var loanPayment in orderedList)
{
// Assuming allLoans payment date is after current date.
if (presentValue == 0)
{
stats[loanPayment.Date] = new LoanPeriodsStatistics(loanPayment.Date, 0, 0, 0);
}
else
{
var daysOfInterest = (loanPayment.Date - currentDate).Days;
var fv = Financial.FGivenP(presentValue, daysOfInterest, interestRate);
var poi = fv - presentValue;
if ((fv < loanPayment.Payment && fv > 0) ||
(fv > loanPayment.Payment && fv < 0))
{
presentValue = 0;
stats[loanPayment.Date] = new LoanPeriodsStatistics(loanPayment.Date, fv, 0, poi);
}
else
{
presentValue = fv - loanPayment.Payment;
stats[loanPayment.Date] = new LoanPeriodsStatistics(loanPayment, presentValue, poi);
}
}
currentDate = loanPayment.Date;
}
return(presentValue);
}
public Loan ApplyPayments(Loan loan, DateTime startTime, LoanPayments payments, out LoanStatistics loanStats)
{
loanStats = new LoanStatistics();
var fv = ApplyPayments(startTime.Year, startTime.Month, startTime.Day, loan.PresentValue, loan.DailyInterestRate,
payments, ref loanStats);
return(new Loan(loan.Name, loan.AnnualPercentageRate, fv, loan.AnnualWorth));
}
public Loan ApplyPayments(Loan loan, out LoanStatistics loanStats)
{
//j Financial.FGivenP((decimal) 6653.54, n, allLoans.MonthlyInterestRate) -
// Financial.FGivenA(annualWorth, n, allLoans.MonthlyInterestRate), 0, annualWorth, out finalPayment);
decimal garbage;
var periods = Financial.FindN(n => Financial.FGivenP(loan.PresentValue, n, loan.MonthlyInterestRate) - Financial.FGivenA(loan.AnnualWorth, n, loan.MonthlyInterestRate), 0,
loan.AnnualWorth, out garbage);
loanStats = new LoanStatistics();
var now = DateTime.Now;
var year = now.Year;
var month = now.Month;
var day = now.Day;
var payments = new LoanPayments();
if (day > 1)
{
month = NextMonth(month, ref year);
}
for (int i = 0; i < periods; i++)
{
var period = new DateTime(year, month, 1);
payments[period] = new LoanPayment {
Year = year, Month = month, Day = day, Payment = loan.AnnualWorth
};
month = NextMonth(month, ref year);
}
if (payments.Count != periods)
{
throw new Exception();
}
var fv = ApplyPayments(now.Year, now.Month, now.Day, loan.PresentValue, loan.DailyInterestRate, payments, ref loanStats);
return(new Loan(loan.Name, loan.AnnualPercentageRate, fv, loan.AnnualWorth));
}