public static void CalculatePercentageOfInterest(decimal runningBalance, LoanPaymentAggregation l)
{
if (runningBalance == 0)
{
l.Percentage = 0;
}
else
{
l.Percentage = ((l.Interest * 12) / runningBalance) * 100;
}
}
public static decimal CalculateTheBalances(MyMoney money, Account account, ObservableCollection <LoanPaymentAggregation> loanPayementsView)
{
decimal runningBalance = 0;
foreach (LoanPaymentAggregation l in loanPayementsView)
{
//-------------------------------------------------------------
// Check to see if we need to re-calculate
// the Principal & Interest amounts using the Percentage
//
if (l.Principal == 0 && l.Interest == 0 && l.Percentage != 0)
{
//
// Recalculate the Interest using the Percentage
//
l.Interest = runningBalance * (l.Percentage / 100) / 12;
// and the Principal if we know the total original Payment
l.Principal = l.Payment - l.Interest;
}
if (l.Interest != 0 && runningBalance != 0)
{
// Reverse calculation of the interest rate
LoanPaymentAggregation.CalculatePercentageOfInterest(runningBalance, l);
}
// Reduce the debt by the amount of the Principal paid
//
// -1 will reverse the amount if this is a mortgage it will change this to -900 * -1 == 900
//
runningBalance += l.Principal * -1;
// Snap shot the balance due at each payment
l.Balance = runningBalance;
}
return(runningBalance);
}
private static LoanPaymentAggregation AddPaymentIfMatchingCategoriesForPrincipalOrInterest(
ObservableCollection <LoanPaymentAggregation> view,
Category category,
Category categoryPrincipal,
Category categoryInterest,
Transaction t,
Split s, // Could be null if this is a basic single transaction with no split,
Account transactionAccount,
DateTime date,
decimal amount
)
{
if (categoryPrincipal == null || categoryInterest == null)
{
return(null);
}
bool matchedThePrincipalCategory = false;
bool matchedTheInterestCategory = false;
decimal principal = 0;
decimal interest = 0;
if (categoryPrincipal.Contains(category))
{
principal = amount;
matchedThePrincipalCategory = true;
}
if (categoryInterest.Contains(category))
{
interest = amount;
matchedTheInterestCategory = true;
}
if (matchedThePrincipalCategory == false && matchedTheInterestCategory == false)
{
// No match to either
return(null);
}
LoanPaymentAggregation lp = GetLastEntry(view);
if (lp != null && lp.Transaction == t)
{
// This is from the same transaction split entry
// we will attempt to merge the PRINCIPAL and the INTEREST onto the same View Loan Entry
}
else
{
// New view projection
lp = new LoanPaymentAggregation();
lp.Transaction = t;
lp.Payment = TransactionAmountMinusAllOtherUnrelatedSplits(t, categoryPrincipal, categoryInterest);
lp.Account = transactionAccount;
lp.Date = date;
lp.Category = category;
view.Add(lp);
}
if (matchedThePrincipalCategory)
{
lp.Principal = principal;
}
if (matchedTheInterestCategory)
{
lp.Interest = interest;
}
if (s != null)
{
if (matchedThePrincipalCategory)
{
lp.SplitForPrincipal = s;
}
if (matchedTheInterestCategory)
{
lp.SplitForInterest = s;
}
}
return(lp);
}
/// <summary>
/// Loans are built from 2 Categories - Principal + Interested
/// </summary>
/// <param name="toDate"></param>
static public ObservableCollection <LoanPaymentAggregation> GetLoanPayementsAggregation(MyMoney money, Account a)
{
ObservableCollection <LoanPaymentAggregation> view = new ObservableCollection <LoanPaymentAggregation>();
Category categoryPrincipal = a.CategoryForPrincipal;
Category categoryInterest = a.CategoryForInterest;
//-----------------------------------------------------------------
// Get the loan transaction related to the 2 categories set
// to this account. Category for Principal & Category for Interest
//
foreach (Transaction t in money.Transactions.GetAllTransactions())
{
if (t.Splits != null && t.Splits.Count > 0)
{
foreach (Split s in t.Splits)
{
if (s.Category != null)
{
AddPaymentIfMatchingCategoriesForPrincipalOrInterest(view, s.Category, categoryPrincipal, categoryInterest, t, s, t.Account, t.Date, s.Amount);
}
}
}
else
{
if (t.Category != null)
{
AddPaymentIfMatchingCategoriesForPrincipalOrInterest(view, t.Category, categoryPrincipal, categoryInterest, t, null, t.Account, t.Date, t.Amount);
}
}
}
//-----------------------------------------------------------------
// Additional manual entry made for this Loan
//
foreach (LoanPayment l in money.LoanPayments)
{
if (!l.IsDeleted)
{
if (l.AccountId == a.Id)
{
LoanPaymentAggregation lp = new LoanPaymentAggregation();
lp.Account = a;
lp.Date = l.Date;
lp.Principal = l.Principal;
lp.Interest = l.Interest;
lp.Payment = l.Principal + l.Interest;
lp.LoanPayementManualEntry = l;
view.Add(lp);
}
}
}
//-----------------------------------------------------------------
// Sort and recalculate the running balance for all the payment made
// to this Loan
//
var sorted = from item in view
orderby item.Date ascending
select item;
ObservableCollection <LoanPaymentAggregation> list = new ObservableCollection <LoanPaymentAggregation>(sorted);
// cannot carry a credit on a loan account, so if the balance is > 0 make it 0.
a.Balance = CalculateTheBalances(money, a, list);
return(list);
}
