test amortisation for declining balance and support irregular first repayment on flat loans.

mifosng-provider/src/main/java/org/mifosng/platform/loanschedule/domain/AmortizationLoanScheduleGeneratorFactory.java

@@ -0,0 +1,26 @@
+package org.mifosng.platform.loanschedule.domain;
+
+import org.mifosng.platform.loan.domain.AmortizationMethod;
+
+public class AmortizationLoanScheduleGeneratorFactory {
+
+	public AmortizationLoanScheduleGenerator createGenerator(final AmortizationMethod amortizationMethod) {
+		
+		AmortizationLoanScheduleGenerator generator = new EqualInstallmentsAmortizationLoanScheduleGenerator();
+		
+		switch (amortizationMethod) {
+		case INVALID:
+			generator = new EqualInstallmentsAmortizationLoanScheduleGenerator();
+			break;
+		case EQUAL_INSTALLMENTS:
+			generator = new EqualInstallmentsAmortizationLoanScheduleGenerator();
+			break;
+		case EQUAL_PRINCIPAL:
+			generator = new EqualPrincipalAmortizationLoanScheduleGenerator();
+			break;
+		}
+		
+		return generator;
+	}
+
+}

mifosng-provider/src/main/java/org/mifosng/platform/loanschedule/domain/DecliningBalanceMethodLoanScheduleGenerator.java

@@ -1,17 +1,11 @@
 package org.mifosng.platform.loanschedule.domain;
 
 import java.math.BigDecimal;
-import java.util.ArrayList;
 import java.util.List;
 
-import org.joda.time.Days;
 import org.joda.time.LocalDate;
 import org.mifosng.platform.api.data.CurrencyData;
 import org.mifosng.platform.api.data.LoanSchedule;
-import org.mifosng.platform.api.data.MoneyData;
-import org.mifosng.platform.api.data.ScheduledLoanInstallment;
-import org.mifosng.platform.currency.domain.MonetaryCurrency;
-import org.mifosng.platform.currency.domain.Money;
 import org.mifosng.platform.loan.domain.AmortizationMethod;
 import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
 import org.mifosng.platform.loan.domain.PeriodFrequencyType;
@@ -37,6 +31,7 @@ public class DecliningBalanceMethodLoanScheduleGenerator implements LoanSchedule
 
 	private final ScheduledDateGenerator scheduledDateGenerator = new DefaultScheduledDateGenerator();
 	private final PeriodicInterestRateCalculator periodicInterestRateCalculator = new PeriodicInterestRateCalculator();
+	private final AmortizationLoanScheduleGeneratorFactory amortizationLoanScheduleGeneratorFactory = new AmortizationLoanScheduleGeneratorFactory();
 	
 	@Override
 	public LoanSchedule generate(
@@ -57,7 +52,8 @@ public class DecliningBalanceMethodLoanScheduleGenerator implements LoanSchedule
 		final BigDecimal periodInterestRateForRepaymentPeriod = this.periodicInterestRateCalculator.calculateFrom(loanScheduleInfo);
 		
 		// Determine with 'amortisation' approach to use
-		AmortizationLoanScheduleGenerator generator = new EqualInstallmentsAmortizationLoanScheduleGenerator();
+		AmortizationLoanScheduleGenerator generator = this.amortizationLoanScheduleGeneratorFactory.createGenerator(loanScheduleInfo.getAmortizationMethod());
+		
 		return generator.generate(loanScheduleInfo, disbursementDate, firstRepaymentDate, interestCalculatedFrom, currencyData,
 				periodInterestRateForRepaymentPeriod, idealDisbursementDateBasedOnFirstRepaymentDate, scheduledDates);
 	}

mifosng-provider/src/main/java/org/mifosng/platform/loanschedule/domain/DefaultLoanScheduleGeneratorFactory.java

@@ -12,7 +12,7 @@ public class DefaultLoanScheduleGeneratorFactory implements
 
 		switch (interestMethod) {
 		case FLAT:
-			loanScheduleGenerator = new FlatLoanScheduleGenerator();
+			loanScheduleGenerator = new FlatMethodLoanScheduleGenerator();
 			break;
 		case DECLINING_BALANCE:
 			loanScheduleGenerator = new DecliningBalanceMethodLoanScheduleGenerator();

mifosng-provider/src/main/java/org/mifosng/platform/loanschedule/domain/EqualPrincipalAmortizationLoanScheduleGenerator.java

@@ -0,0 +1,102 @@
+package org.mifosng.platform.loanschedule.domain;
+
+import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.joda.time.Days;
+import org.joda.time.LocalDate;
+import org.mifosng.platform.api.data.CurrencyData;
+import org.mifosng.platform.api.data.LoanSchedule;
+import org.mifosng.platform.api.data.MoneyData;
+import org.mifosng.platform.api.data.ScheduledLoanInstallment;
+import org.mifosng.platform.currency.domain.MonetaryCurrency;
+import org.mifosng.platform.currency.domain.Money;
+import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
+
+public class EqualPrincipalAmortizationLoanScheduleGenerator implements AmortizationLoanScheduleGenerator {
+
+	private final PeriodicInterestRateCalculator periodicInterestRateCalculator = new PeriodicInterestRateCalculator();
+	private final PaymentPeriodsInOneYearCalculator paymentPeriodsInOneYearCalculator = new DefaultPaymentPeriodsInOneYearCalculator();
+	
+	@Override
+	public LoanSchedule generate(final LoanProductRelatedDetail loanScheduleInfo, 
+			final LocalDate disbursementDate, 
+			final LocalDate firstRepaymentDate,
+			final LocalDate interestCalculatedFrom,
+			final CurrencyData currencyData,
+			final BigDecimal periodInterestRateForRepaymentPeriod, 
+			final LocalDate idealDisbursementDateBasedOnFirstRepaymentDate,
+			final List<LocalDate> scheduledDates) {
+		
+		List<ScheduledLoanInstallment> scheduledLoanInstallments = new ArrayList<ScheduledLoanInstallment>();
+		
+		// 1. we know 'principal' must be equal over repayments so use this to calculate interest and thus total repayment due.
+		final MonetaryCurrency monetaryCurrency = loanScheduleInfo.getPrincipal().getCurrency();
+		Money totalDuePerInstallment = Money.zero(monetaryCurrency);
+
+		Money outstandingBalance = loanScheduleInfo.getPrincipal();
+		Money totalPrincipal = Money.zero(monetaryCurrency);
+		Money totalInterest = Money.zero(monetaryCurrency);
+		
+		double interestCalculationGraceOnRepaymentPeriodFraction = this.paymentPeriodsInOneYearCalculator.calculateRepaymentPeriodAsAFractionOfDays(loanScheduleInfo.getRepaymentPeriodFrequencyType(), 
+												loanScheduleInfo.getRepayEvery(), interestCalculatedFrom, scheduledDates, idealDisbursementDateBasedOnFirstRepaymentDate);
+		
+		LocalDate startDate = disbursementDate;
+		int installmentNumber = 1;
+		for (LocalDate scheduledDueDate : scheduledDates) {
+
+			// number of days from startDate to this scheduledDate
+			int daysInPeriod = Days.daysBetween(startDate.toDateMidnight().toDateTime(), scheduledDueDate.toDateMidnight().toDateTime()).getDays();
+			
+			Money interestForInstallment = this.periodicInterestRateCalculator.calculateInterestOn(outstandingBalance, periodInterestRateForRepaymentPeriod, daysInPeriod, loanScheduleInfo);
+			Money principalForInstallment = this.periodicInterestRateCalculator.calculatePrincipalOn(totalDuePerInstallment, interestForInstallment, loanScheduleInfo);
+			
+			if (interestCalculationGraceOnRepaymentPeriodFraction >= Integer.valueOf(1).doubleValue()) {
+				Money graceOnInterestForRepaymentPeriod = interestForInstallment;
+				interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
+				interestCalculationGraceOnRepaymentPeriodFraction = interestCalculationGraceOnRepaymentPeriodFraction - Integer.valueOf(1).doubleValue();
+			} else if (interestCalculationGraceOnRepaymentPeriodFraction > Double.valueOf("0.25") && interestCalculationGraceOnRepaymentPeriodFraction < Integer.valueOf(1).doubleValue()) {
+				Money graceOnInterestForRepaymentPeriod = interestForInstallment.multipliedBy(interestCalculationGraceOnRepaymentPeriodFraction);
+				interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
+				interestCalculationGraceOnRepaymentPeriodFraction = Double.valueOf("0");
+			}
+			
+			totalPrincipal = totalPrincipal.plus(principalForInstallment);
+			totalInterest = totalInterest.plus(interestForInstallment);
+			
+			if (installmentNumber == loanScheduleInfo.getNumberOfRepayments()) {
+				Money principalDifference = totalPrincipal.minus(loanScheduleInfo.getPrincipal());
+				if (principalDifference.isLessThanZero()) {
+					principalForInstallment = principalForInstallment.plus(principalDifference.abs());
+				} else if (principalDifference.isGreaterThanZero()) {
+					principalForInstallment = principalForInstallment.minus(principalDifference.abs());
+				}
+			}
+
+			Money totalInstallmentDue = principalForInstallment.plus(interestForInstallment);
+
+			outstandingBalance = outstandingBalance.minus(principalForInstallment);
+			
+			MoneyData principalPerInstallmentValue = MoneyData.of(currencyData, principalForInstallment.getAmount());
+			MoneyData interestPerInstallmentValue = MoneyData.of(currencyData, interestForInstallment.getAmount());
+			MoneyData totalInstallmentDueValue = MoneyData.of(currencyData, totalInstallmentDue.getAmount());
+			MoneyData outstandingBalanceValue = MoneyData.of(currencyData, outstandingBalance.getAmount());
+					
+			ScheduledLoanInstallment installment = new ScheduledLoanInstallment(
+					Integer.valueOf(installmentNumber), startDate,
+					scheduledDueDate, principalPerInstallmentValue,
+					interestPerInstallmentValue, 
+					totalInstallmentDueValue,
+					outstandingBalanceValue);
+
+			scheduledLoanInstallments.add(installment);
+
+			startDate = scheduledDueDate;
+
+			installmentNumber++;
+		}
+		
+		return new LoanSchedule(scheduledLoanInstallments);
+	}
+}

mifosng-provider/src/main/java/org/mifosng/platform/loanschedule/domain/FlatMethodLoanScheduleGenerator.java

@@ -15,7 +15,7 @@ import org.mifosng.platform.currency.domain.Money;
 import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
 import org.mifosng.platform.loan.domain.PeriodFrequencyType;
 
-public class FlatLoanScheduleGenerator implements LoanScheduleGenerator {
+public class FlatMethodLoanScheduleGenerator implements LoanScheduleGenerator {
 
 	private final ScheduledDateGenerator scheduledDateGenerator = new DefaultScheduledDateGenerator();
 	private final PaymentPeriodsInOneYearCalculator paymentPeriodsInOneYearCalculator = new DefaultPaymentPeriodsInOneYearCalculator();
@@ -49,18 +49,6 @@ public class FlatLoanScheduleGenerator implements LoanScheduleGenerator {
 				.dividedBy(loanScheduleInfo.getNumberOfRepayments(),
 						RoundingMode.HALF_EVEN);
 
-//		BigDecimal paymentPeriodsInYear = BigDecimal
-//				.valueOf(this.paymentPeriodsInOneYearCalculator
-//						.calculate(loanScheduleInfo.getRepaymentPeriodFrequencyType()));
-
-//		BigDecimal periodicInterestRate = loanScheduleInfo
-//				.getAnnualNominalInterestRate()
-//				.divide(paymentPeriodsInYear, mc)
-//				.divide(BigDecimal.valueOf(Double.valueOf("100.0")), mc)
-//				.multiply(BigDecimal.valueOf(loanScheduleInfo.getRepayEvery()));
-
-//		Money interestPerInstallment = loanScheduleInfo.getPrincipal().multiplyRetainScale(periodicInterestRate, RoundingMode.HALF_EVEN);
-
 		Money outstandingBalance = loanScheduleInfo.getPrincipal();
 		Money totalPrincipal = Money.zero(outstandingBalance.getCurrency());
 		Money totalInterest = Money.zero(outstandingBalance.getCurrency());