private static Loan CreateLoan(Loantypes loanType, int tenure, double interestRate, int principal, DateTime payoutDate, IDayCounter dayCalculator)
{
Loan loan;
switch (loanType)
{
case Loantypes.FixedEmiLoan:
loan = new FixedEmiLoan(dayCalculator);
break;
case Loantypes.FixedAmortizationLoan:
loan = new FixedAmortizationLoan(dayCalculator);
break;
case Loantypes.FixedInterestLoan:
loan = new FixedInterestLoan(dayCalculator);
break;
default: throw new ArgumentException("Loan type not implemented");
}
;
loan.TenureYears = tenure;
loan.InterestRate = interestRate;
loan.StartAmount = principal;
loan.CurrentPrincipal = principal;
loan.PayoutDate = payoutDate;
return(loan);
}
static void TestCreatingInvoices(IDayCounter dayCalculator, string filename)
{
var loan = new FixedEmiLoan(dayCalculator)
{
InterestRate = 10,
CurrentPrincipal = 10000,
StartAmount = 10000,
PayoutDate = new DateTime(2017, 10, 01),
TenureYears = 10,
};
var invoices = new List <Invoice>();
var baseDate = loan.PayoutDate;
while (loan.CurrentPrincipal > 0.001)
{
baseDate = baseDate.AddMonths(1);
var date = baseDate.AddDays(-1);
var invoice = loan.AddInvoice(date, new DateTime(date.Year, date.Month, 1), baseDate, 0.0);
loan.CurrentPrincipal -= invoice.Principal;
invoices.Add(invoice);
//Console.WriteLine(invoice.ToString());
//Console.WriteLine($"{invoice.InvoiceDate.ToString("MMM-yyyy")} | {Math.Round(invoice.FullInvoiceAmount, 0, MidpointRounding.AwayFromZero)} | {Math.Round(invoice.Interest, 0, MidpointRounding.AwayFromZero)} | {Math.Round(invoice.Principal, 0, MidpointRounding.AwayFromZero)} | {Math.Round(loan.CurrentPrincipal, 0, MidpointRounding.AwayFromZero)}");
}
Console.WriteLine($"SUM: Principal {invoices.Sum(s => s.Principal)}, Interest: {invoices.Sum(s => s.Interest)}, InvoiceFee: {invoices.Sum(s => s.InvoiceFee)}, LateFee: {invoices.Sum(s => s.LateFee)}");
TestOutput.CreateCSV(invoices, filename);
}
static void TestPayingOnLoan(IDayCounter dayCalculator)
{
var loan = new FixedEmiLoan(dayCalculator)
{
InterestRate = 10,
CurrentPrincipal = 10000,
StartAmount = 10000,
PayoutDate = new DateTime(2017, 01, 01),
TenureYears = 10,
};
var invoices = new List <Invoice>();
var baseDate = loan.PayoutDate;
for (int i = 0; i < 3; i++)
{
baseDate = baseDate.AddMonths(1);
var date = baseDate.AddDays(-1);
var invoice = loan.AddInvoice(date, new DateTime(date.Year, date.Month, 1), baseDate, 0.0);
//loan.CurrentPrincipal -= invoice.Principal;
invoices.Add(invoice);
//Console.WriteLine(invoice.ToString());
//Console.WriteLine($"{invoice.InvoiceDate.ToString("MMM-yyyy")} | {Math.Round(invoice.FullInvoiceAmount, 0, MidpointRounding.AwayFromZero)} | {Math.Round(invoice.Interest, 0, MidpointRounding.AwayFromZero)} | {Math.Round(invoice.Principal, 0, MidpointRounding.AwayFromZero)} | {Math.Round(loan.CurrentPrincipal, 0, MidpointRounding.AwayFromZero)}");
}
loan.Invoices = invoices;
var payment = loan.Pay(new DateTime(2017, 03, 31), 5000.0);
Console.WriteLine(payment.ToString());
Console.WriteLine($"SUM: Principal {invoices.Sum(s => s.Principal)}, Interest: {invoices.Sum(s => s.Interest)}, InvoiceFee: {invoices.Sum(s => s.InvoiceFee)}, LateFee: {invoices.Sum(s => s.LateFee)}");
Console.WriteLine("Current Principal: " + loan.CurrentPrincipal);
}
public void AddInvoiceTest()
{
var dayCalculator = new Thirty360Isda();
var loan = new FixedEmiLoan(dayCalculator)
{
InterestRate = 10,
CurrentPrincipal = 10000,
StartAmount = 10000,
PayoutDate = new DateTime(2017, 10, 01),
TenureYears = 10,
};
Invoice invoice = new Invoice();
var invoices = new List <Invoice>();
var baseDate = loan.PayoutDate;
while (loan.CurrentPrincipal >= 0.01)
{
baseDate = baseDate.AddMonths(1);
var date = baseDate.AddDays(-1);
invoice = loan.AddInvoice(date, new DateTime(date.Year, date.Month, 1), baseDate, 0.0);
loan.CurrentPrincipal -= invoice.Principal; // Fake payments on the loan.
invoices.Add(invoice);
}
// Assert that the sum is correct.
var sumPrincipal = invoices.Sum(s => s.Principal);
Assert.IsTrue(Math.Abs(sumPrincipal - 10000) <= 0.01d, $"Principal: Expected less than 0.01, found {sumPrincipal}");
var sumInterest = invoices.Sum(s => s.Interest);
Assert.IsTrue(Math.Abs(invoices.Sum(s => s.Interest) - 5858.1799999999994) <= 0.01d, $"Interest: Expected 5858.179, found {sumInterest}");
Assert.IsTrue(Math.Abs(invoice.Principal - 0.18d) < 0.01d, $"Last invoice principal: Expected 0.180, found {invoice.Principal}.");
Assert.IsTrue(Math.Abs(invoice.Interest - 0.00d) < 0.01d, $"Last invoice Interest: Expected 0.000, found {invoice.Interest}.");
}
