/// <summary>
/// Gets a Date based on a given period in the Loan Lifecycle.
/// </summary>
internal static DateTime GetDateFromPeriod(PeriodSpan Span, DateTime StartDate, UnitPeriod CommonPeriod)
{
DateTime dtReturn;
try
{
if (CommonPeriod.periodType == UnitPeriodType.Monthly)
{
dtReturn = StartDate.AddMonths(CommonPeriod.numPeriods * Span.Periods).AddDays(Span.OddDays);
}
else if (CommonPeriod.periodType == UnitPeriodType.Yearly)
{
dtReturn = StartDate.AddYears(CommonPeriod.numPeriods * Span.Periods).AddDays(Span.OddDays);
}
else if (CommonPeriod.periodType == UnitPeriodType.Weekly)
{
dtReturn = StartDate.AddDays(CommonPeriod.numPeriods * Span.Periods * 7).AddDays(Span.OddDays);
}
else
{
dtReturn = StartDate.AddDays(CommonPeriod.numPeriods * Span.Periods);
}
return(dtReturn);
}
catch (Exception ex)
{
ApplicationException newex = new ApplicationException("Exception in DateTimeCalculations.GetDateFromPeriod", ex);
throw(newex);
}
}
/// <summary>
/// Mark the Line Item As Complete. Must only be done by the Line Item Collection
/// </summary>
internal void Complete()
{
if (this.m_DateType == DateType.Date)
{
this.m_Span = DateTimeCalculations.GetNumberPeriods(this.Parent.StartDate, this.m_Date, this.Parent.CommonPeriod);
}
else
{
if (this.Parent.CommonPeriod.numPeriods < 1 || this.Parent.CommonPeriod.numPeriods < 1)
{
throw new ApplicationException("Cannot mark LineItem for completion. A period has been specified, but there is no common period for the Parent LineItemCollection Class");
}
this.m_Date = DateTimeCalculations.GetDateFromPeriod(this.m_Span, this.Parent.StartDate, this.Parent.CommonPeriod);
}
}
internal static double GetPVIFA(DateTime StartDate, DateTime CurrLIDate, UnitPeriod frequency, double APR, double PeriodsPerYear, double DaysPerPeriod, int NumberOccurrences, UnitPeriod CommonPeriod)
{
StringBuilder sb = new StringBuilder();
int ic = 1;
double pvifa = 0.0d; //return value, running tally of PVIF
PeriodSpan lastSpan;
PeriodSpan currSpan = DateTimeCalculations.GetNumberPeriods(StartDate, CurrLIDate, CommonPeriod);
lastSpan.OddDays = 0;
lastSpan.Periods = 0;
for (int i = 0; i < NumberOccurrences; i++)
{
//get the PVIF for this current item and add to the pvifa
pvifa += GetPVIF(currSpan, APR, PeriodsPerYear, DaysPerPeriod);
sb.AppendLine(ic.ToString() + " " + CurrLIDate.ToString() + " " + currSpan.Periods.ToString() + currSpan.OddDays.ToString() + " " + pvifa.ToString());
//TODO... figure out how to determine the recurrence in periods if
//periods other than a monthly type or annual are passed in.
//Perhaps we should restrict to only dates instead?
lastSpan = currSpan;
CurrLIDate = DateTimeCalculations.AddPeriodToDate(CurrLIDate, frequency);
currSpan = DateTimeCalculations.GetNumberPeriods(StartDate, CurrLIDate, CommonPeriod);
}
return(pvifa);
}
internal static double GetPVIF(PeriodSpan span, double APR, double PeriodsPerYear, double DaysPerPeriod)
{
return((double)(1 / (Math.Pow((1 + (APR / PeriodsPerYear)), (double)span.Periods) * (1 + ((span.OddDays / DaysPerPeriod) * (APR / PeriodsPerYear))))));
}
