private CreditCalculatorResultVM GetResultsForModel(CreditCalcResults res)
{
CreditCalculatorResultVM mRes = new CreditCalculatorResultVM();
mRes.AnnualPercentageRate = res.AnnualPercentageRate;
mRes.TotalFees = res.TotalFees;
mRes.TotalInstallments = res.TotalInstallments;
mRes.TotalInstallmentsWithTotalFeesAndRates = res.TotalInstallmentsWithTotalFeesAndRates;
mRes.TotalRates = res.TotalRates;
mRes.MonthlyInstallments = new List <MonthlyResultVM>();
foreach (var m in res.MonthlyInstallments)
{
MonthlyResultVM mcalc = new MonthlyResultVM();
mcalc.Date = m.Date;
mcalc.Fees = m.Fees;
mcalc.Installment = m.Installment;
mcalc.PrincipalRemainder = m.PrincipalRemainder;
mcalc.PrinicpalInstallment = m.PrinicpalInstallment;
mcalc.RateInstallment = m.RateInstallment;
mcalc.RowNumber = m.RowNumber;
mcalc.TotalInstallment = m.TotalInstallment;
mRes.MonthlyInstallments.Add(mcalc);
}
return(mRes);
}
/// <summary>
/// Смята резултатите на финансовия калкулатор
/// </summary>
/// <param name="p"></param>
/// <returns></returns>
public CreditCalcResults Calculate(CreditCalcParams p)
{
IsParamsValid(p);
CreditCalcResults res = null;
if (p.IsAnnuityInstallments)
{
res = CalculateAnnuity(p);
}
else
{
res = CalculateDescending(p);
}
APRCalculator aprCalc = new APRCalculator(p.Amount);
foreach (var m in res.MonthlyInstallments)
{
if (m.RowNumber == 0)
{
aprCalc.AddInstalment(m.Fees, 0);
}
else
{
aprCalc.AddInstalment(m.TotalInstallment, 365.25M / 12M * m.RowNumber);
}
res.TotalFees += m.Fees;
res.TotalRates += m.RateInstallment;
res.TotalInstallments += m.Installment;
}
res.AnnualPercentageRate = aprCalc.Calculate();
res.TotalInstallmentsWithTotalFeesAndRates = res.TotalInstallments + res.TotalFees;
return(res);
}
public ActionResult FinanceCalculator(CreditCalculatorParamsVM model)
{
if (!model.IsModelValid(ModelState))
{
return(PartialView("_InvalidCreditParamsPartial", model));
}
var parameters = GetParamsFromModel(model);
CreditCalcResults creditResult = this.calculatorService.CalculateCredit(parameters);
CreditCalculatorResultVM creditViewModelResult = GetResultsForModel(creditResult);
return(PartialView("_CreditResultsPartial", creditViewModelResult));
}
/// <summary>
/// Функция, пресмятаща резултатите от погасителния план при намаляващи месечни вноски
/// </summary>
/// <param name="p"></param>
/// <returns></returns>
private CreditCalcResults CalculateDescending(CreditCalcParams p)
{
CreditCalcResults res = new CreditCalcResults();
res.MonthlyInstallments = new List <MonthlyResult>();
res.MonthlyInstallments.Add(GetZeroMonth(p));
decimal principalInstallment = Math.Round(p.Amount / (p.Period - (p.GratisPeriod ?? 0)), 2);
for (int i = 1; i <= p.Period; i++)
{
MonthlyResult m = new MonthlyResult();
if (i == 1)
{
m.PrincipalRemainder = p.Amount;
}
else
{
m.PrincipalRemainder = res.MonthlyInstallments[i - 1].CurrentPrincipallRemainder();
}
m.RowNumber = i;
m.Date = DateTime.Now.AddMonths(i);
bool isInPromotion = (i <= (p.PromotionPeriod ?? 0));
bool isInGratis = (i <= (p.GratisPeriod ?? 0));
m.RateInstallment = Math.Round((decimal)(m.PrincipalRemainder * (isInPromotion ? p.PromotionRate : p.Rate) / 100) / 12, 2);
if (isInGratis)
{
m.PrinicpalInstallment = 0;
}
else
{
m.PrinicpalInstallment = (i == p.Period) ? Math.Round(p.Amount - (i - 1 - (p.GratisPeriod ?? 0)) * principalInstallment, 2) : principalInstallment;
}
m.Installment = (isInGratis ? 0 : m.PrinicpalInstallment) + m.RateInstallment;
if (i % 12 == 1 && i != 1)
{
m.Fees = MonthlyFeesCalc(p, m) + AnnualFeesCalc(p, m);
}
else
{
m.Fees = MonthlyFeesCalc(p, m);
}
m.TotalInstallment = m.Installment + m.Fees;
res.MonthlyInstallments.Add(m);
}
return(res);
}
/// <summary>
/// Функция, пресмятаща резултатите от погасителния план при анюитетни вноски
/// </summary>
/// <param name="p"></param>
/// <returns></returns>
private CreditCalcResults CalculateAnnuity(CreditCalcParams p)
{
CreditCalcResults res = new CreditCalcResults();
res.MonthlyInstallments = new List <MonthlyResult>();
res.MonthlyInstallments.Add(GetZeroMonth(p));
bool hasPromotion = p.PromotionPeriod.HasValue;
decimal pmtPromotional = hasPromotion ? PMT(p.PromotionRate.Value, p.Period - (p.GratisPeriod ?? 0), p.Amount) : 0;
decimal pmtNormal = hasPromotion ? 0 : PMT(p.Rate, p.Period - (p.GratisPeriod ?? 0), p.Amount);
decimal promotionalInstallment = 0;
for (int i = 1; i <= p.Period; i++)
{
MonthlyResult m = new MonthlyResult();
if (i == 1)
{
m.PrincipalRemainder = p.Amount;
}
else
{
m.PrincipalRemainder = res.MonthlyInstallments[i - 1].CurrentPrincipallRemainder();
}
m.RowNumber = i;
m.Date = DateTime.Now.AddMonths(i);
if (i <= (p.PromotionPeriod ?? 0))
{
m.RateInstallment = Math.Round((decimal)(m.PrincipalRemainder * p.PromotionRate / 100) / 12, 2);
if (i <= (p.GratisPeriod ?? 0))
{
m.Installment = m.RateInstallment;
}
else
{
m.Installment = pmtPromotional;
}
m.PrinicpalInstallment = m.Installment - m.RateInstallment;
promotionalInstallment += m.PrinicpalInstallment;
}
else
{
m.RateInstallment = Math.Round((decimal)(m.PrincipalRemainder * p.Rate / 100) / 12, 2);
if (i <= (p.GratisPeriod ?? 0))
{
m.Installment = m.RateInstallment;
}
else
{
if (pmtNormal == 0)
{
pmtNormal = PMT(p.Rate, p.Period - Math.Max(p.PromotionPeriod.Value, p.GratisPeriod ?? 0), p.Amount - promotionalInstallment);
}
if (i == p.Period)
{
pmtNormal = PMT(p.Rate, 1, m.PrincipalRemainder);
}
m.Installment = pmtNormal;
}
m.PrinicpalInstallment = m.Installment - m.RateInstallment;
}
if (i % 12 == 1 && i != 1)
{
m.Fees = MonthlyFeesCalc(p, m) + AnnualFeesCalc(p, m);
}
else
{
m.Fees = MonthlyFeesCalc(p, m);
}
m.TotalInstallment = m.Installment + m.Fees;
res.MonthlyInstallments.Add(m);
}
return(res);
}
