FINERACT-2398: Re-amortization:- Preview Schedule API during re-amortization

fineract-provider/src/main/java/org/apache/fineract/portfolio/loanaccount/api/LoanTransactionsApiResource.java

@@ -66,6 +66,7 @@ import org.apache.fineract.infrastructure.core.service.DateUtils;
 import org.apache.fineract.infrastructure.core.service.ExternalIdFactory;
 import org.apache.fineract.infrastructure.security.service.PlatformSecurityContext;
 import org.apache.fineract.portfolio.loanaccount.api.request.ReAgePreviewRequest;
+import org.apache.fineract.portfolio.loanaccount.api.request.ReAmortizationPreviewRequest;
 import org.apache.fineract.portfolio.loanaccount.data.LoanRepaymentScheduleInstallmentData;
 import org.apache.fineract.portfolio.loanaccount.data.LoanTransactionData;
 import org.apache.fineract.portfolio.loanaccount.domain.LoanTransactionType;
@@ -76,6 +77,7 @@ import org.apache.fineract.portfolio.loanaccount.loanschedule.data.LoanScheduleD
 import org.apache.fineract.portfolio.loanaccount.service.LoanChargePaidByReadService;
 import org.apache.fineract.portfolio.loanaccount.service.LoanReadPlatformService;
 import org.apache.fineract.portfolio.loanaccount.service.reaging.LoanReAgingService;
+import org.apache.fineract.portfolio.loanaccount.service.reamortization.LoanReAmortizationService;
 import org.apache.fineract.portfolio.paymenttype.data.PaymentTypeData;
 import org.apache.fineract.portfolio.paymenttype.service.PaymentTypeReadPlatformService;
 import org.springframework.data.domain.Page;
@@ -111,6 +113,7 @@ public class LoanTransactionsApiResource {
     private final PaymentTypeReadPlatformService paymentTypeReadPlatformService;
     private final LoanChargePaidByReadService loanChargePaidByReadService;
     private final LoanReAgingService loanReAgingService;
+    private final LoanReAmortizationService loanReAmortizationService;
 
     @GET
     @Path("{loanId}/transactions/template")
@@ -806,4 +809,26 @@ public class LoanTransactionsApiResource {
         return loanReAgingService.previewReAge(null, loanExternalId, reAgePreviewRequest);
     }
 
+    @GET
+    @Path("{loanId}/transactions/reamortized-preview")
+    @Produces({ MediaType.APPLICATION_JSON })
+    @Operation(summary = "Preview Re-Amortized Schedule", description = "Generates a preview of the re-amortized loan schedule based on the provided parameters without creating any transactions or modifying the loan.")
+    public LoanScheduleData previewReAmortizationSchedule(
+            @PathParam("loanId") @Parameter(description = "loanId", required = true) final Long loanId,
+            @Valid @BeanParam final ReAmortizationPreviewRequest reAmortizationPreviewRequest) {
+        this.context.authenticatedUser().validateHasReadPermission(RESOURCE_NAME_FOR_PERMISSIONS);
+        return loanReAmortizationService.previewReAmortization(loanId, null, reAmortizationPreviewRequest);
+    }
+
+    @GET
+    @Path("external-id/{loanExternalId}/transactions/reamortized-preview")
+    @Produces({ MediaType.APPLICATION_JSON })
+    @Operation(summary = "Preview Re-amortized Schedule", description = "Generates a preview of the re-amortized loan schedule based on the provided parameters without creating any transactions or modifying the loan.")
+    public LoanScheduleData previewReAmortizationSchedule(
+            @PathParam("loanExternalId") @Parameter(description = "loanExternalId", required = true) final String loanExternalId,
+            @Valid @BeanParam final ReAmortizationPreviewRequest reAmortizationPreviewRequest) {
+        this.context.authenticatedUser().validateHasReadPermission(RESOURCE_NAME_FOR_PERMISSIONS);
+        return loanReAmortizationService.previewReAmortization(null, loanExternalId, reAmortizationPreviewRequest);
+    }
+
 }

fineract-provider/src/main/java/org/apache/fineract/portfolio/loanaccount/api/request/ReAmortizationPreviewRequest.java

@@ -0,0 +1,48 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.fineract.portfolio.loanaccount.api.request;
+
+import io.swagger.v3.oas.annotations.Parameter;
+import jakarta.validation.constraints.NotBlank;
+import jakarta.ws.rs.QueryParam;
+import java.io.Serial;
+import java.io.Serializable;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import org.apache.fineract.portfolio.loanaccount.domain.reamortization.LoanReAmortizationInterestHandlingType;
+import org.apache.fineract.validation.constraints.EnumValue;
+
+@Builder
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+public class ReAmortizationPreviewRequest implements Serializable {
+
+    @Serial
+    private static final long serialVersionUID = 1L;
+
+    @QueryParam("reAmortizationInterestHandling")
+    @Parameter(description = "The interest handling type (DEFAULT, WAIVE_INTEREST, EQUAL_AMORTIZATION_INTEREST_SPLIT)", required = true)
+    @NotBlank(message = "{org.apache.fineract.reamortization.interest-handling-type.not-blank}")
+    @EnumValue(enumClass = LoanReAmortizationInterestHandlingType.class, message = "{org.apache.fineract.interest-handling-type.invalid}")
+    private String reAmortizationInterestHandling;
+
+}

fineract-provider/src/main/java/org/apache/fineract/portfolio/loanaccount/service/reamortization/LoanReAmortizationService.java

@@ -22,10 +22,12 @@ import static java.math.BigDecimal.ZERO;
 
 import java.math.BigDecimal;
 import java.time.LocalDate;
+import java.util.Collection;
 import java.util.Comparator;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 import lombok.RequiredArgsConstructor;
 import org.apache.fineract.infrastructure.codes.domain.CodeValue;
 import org.apache.fineract.infrastructure.codes.domain.CodeValueRepository;
@@ -40,17 +42,27 @@ import org.apache.fineract.infrastructure.event.business.domain.loan.reamortizat
 import org.apache.fineract.infrastructure.event.business.domain.loan.transaction.reamortization.LoanReAmortizeTransactionBusinessEvent;
 import org.apache.fineract.infrastructure.event.business.domain.loan.transaction.reamortization.LoanUndoReAmortizeTransactionBusinessEvent;
 import org.apache.fineract.infrastructure.event.business.service.BusinessEventNotifierService;
+import org.apache.fineract.organisation.monetary.data.CurrencyData;
 import org.apache.fineract.organisation.monetary.domain.Money;
 import org.apache.fineract.portfolio.loanaccount.api.LoanApiConstants;
 import org.apache.fineract.portfolio.loanaccount.api.LoanReAmortizationApiConstants;
+import org.apache.fineract.portfolio.loanaccount.api.request.ReAmortizationPreviewRequest;
+import org.apache.fineract.portfolio.loanaccount.data.DisbursementData;
+import org.apache.fineract.portfolio.loanaccount.data.RepaymentScheduleRelatedLoanData;
 import org.apache.fineract.portfolio.loanaccount.domain.Loan;
+import org.apache.fineract.portfolio.loanaccount.domain.LoanRepaymentScheduleInstallment;
 import org.apache.fineract.portfolio.loanaccount.domain.LoanTransaction;
+import org.apache.fineract.portfolio.loanaccount.domain.LoanTransactionRepaymentPeriodData;
 import org.apache.fineract.portfolio.loanaccount.domain.LoanTransactionRepository;
 import org.apache.fineract.portfolio.loanaccount.domain.LoanTransactionType;
 import org.apache.fineract.portfolio.loanaccount.domain.reamortization.LoanReAmortizationInterestHandlingType;
 import org.apache.fineract.portfolio.loanaccount.domain.reamortization.LoanReAmortizationParameter;
+import org.apache.fineract.portfolio.loanaccount.loanschedule.data.LoanScheduleData;
+import org.apache.fineract.portfolio.loanaccount.repository.LoanCapitalizedIncomeBalanceRepository;
 import org.apache.fineract.portfolio.loanaccount.serialization.LoanChargeValidator;
 import org.apache.fineract.portfolio.loanaccount.service.LoanAssembler;
+import org.apache.fineract.portfolio.loanaccount.service.LoanReadPlatformService;
+import org.apache.fineract.portfolio.loanaccount.service.LoanRepaymentScheduleService;
 import org.apache.fineract.portfolio.loanaccount.service.LoanScheduleService;
 import org.apache.fineract.portfolio.loanaccount.service.ReprocessLoanTransactionsService;
 import org.springframework.stereotype.Service;
@@ -70,6 +82,9 @@ public class LoanReAmortizationService {
     private final ReprocessLoanTransactionsService reprocessLoanTransactionsService;
     private final CodeValueRepository codeValueRepository;
     private final LoanScheduleService loanScheduleService;
+    private final LoanRepaymentScheduleService loanRepaymentScheduleService;
+    private final LoanReadPlatformService loanReadPlatformService;
+    private final LoanCapitalizedIncomeBalanceRepository loanCapitalizedIncomeBalanceRepository;
 
     public CommandProcessingResult reAmortize(final Long loanId, final JsonCommand command) {
         final Loan loan = loanAssembler.assembleFrom(loanId);
@@ -77,7 +92,7 @@ public class LoanReAmortizationService {
 
         final LoanTransaction reAmortizeTransaction = createReAmortizeTransaction(loan, command);
         reAmortizeTransaction.setLoanReAmortizationParameter(createReAmortizationParameter(reAmortizeTransaction, command));
-        processReAmortizationTransaction(loan, reAmortizeTransaction);
+        processReAmortizationTransaction(loan, reAmortizeTransaction, true);
         loanTransactionRepository.saveAndFlush(reAmortizeTransaction);
 
         final Map<String, Object> changes = new LinkedHashMap<>();
@@ -130,6 +145,36 @@ public class LoanReAmortizationService {
                 .with(changes).build();
     }
 
+    @Transactional(readOnly = true)
+    public LoanScheduleData previewReAmortization(final Long loanId, final String loanExternalId,
+            final ReAmortizationPreviewRequest reAmortizationPreviewRequest) {
+        final Loan loan = loanId != null ? loanAssembler.assembleFrom(loanId)
+                : loanAssembler.assembleFrom(ExternalIdFactory.produce(loanExternalId), false);
+        return previewReAmortization(loan, reAmortizationPreviewRequest);
+    }
+
+    private LoanScheduleData previewReAmortization(final Loan loan, final ReAmortizationPreviewRequest reAmortizationPreviewRequest) {
+        reAmortizationValidator.validateReAmortize(loan);
+
+        final LoanTransaction reAmortizeTransaction = createReAmortizeTransactionFromPreviewRequest(loan, reAmortizationPreviewRequest);
+        processReAmortizationTransaction(loan, reAmortizeTransaction, false);
+        loan.updateLoanScheduleDependentDerivedFields();
+
+        final CurrencyData currencyData = new CurrencyData(loan.getCurrencyCode(), null, loan.getCurrency().getDigitsAfterDecimal(),
+                loan.getCurrency().getInMultiplesOf(), null, null);
+        final RepaymentScheduleRelatedLoanData repaymentScheduleRelatedLoanData = new RepaymentScheduleRelatedLoanData(
+                loan.getDisbursementDate(), loan.getDisbursementDate(), currencyData, loan.getPrincipal().getAmount(),
+                loan.getInArrearsTolerance().getAmount(), ZERO);
+        final Collection<DisbursementData> disbursementData = loanReadPlatformService.retrieveLoanDisbursementDetails(loan.getId());
+        final Collection<LoanTransactionRepaymentPeriodData> capitalizedIncomeData = loanCapitalizedIncomeBalanceRepository
+                .findRepaymentPeriodDataByLoanId(loan.getId());
+        final List<LoanRepaymentScheduleInstallment> sortedInstallments = loan.getRepaymentScheduleInstallments().stream()
+                .sorted(Comparator.comparingInt(LoanRepaymentScheduleInstallment::getInstallmentNumber)).collect(Collectors.toList());
+
+        return loanRepaymentScheduleService.extractLoanScheduleData(sortedInstallments, repaymentScheduleRelatedLoanData, disbursementData,
+                capitalizedIncomeData, loan.isInterestRecalculationEnabled(), loan.getLoanProductRelatedDetail().getLoanScheduleType());
+    }
+
     private void reverseReAmortizeTransaction(LoanTransaction reAmortizeTransaction, JsonCommand command) {
         ExternalId reversalExternalId = externalIdFactory.createFromCommand(command,
                 LoanReAmortizationApiConstants.externalIdParameterName);
@@ -163,6 +208,23 @@ public class LoanReAmortizationService {
                 txPrincipalAmount, ZERO, ZERO, ZERO, null, false, null, txExternalId);
     }
 
+    private LoanTransaction createReAmortizeTransactionFromPreviewRequest(final Loan loan,
+            final ReAmortizationPreviewRequest reAmortizationPreviewRequest) {
+        // re-amortization transaction date is always the current business date
+        final LocalDate transactionDate = DateUtils.getBusinessLocalDate();
+        final Money txPrincipal = loan.getTotalPrincipalOutstandingUntil(transactionDate);
+        final BigDecimal txPrincipalAmount = txPrincipal.getAmount();
+
+        final LoanTransaction reAmortizationTransaction = new LoanTransaction(loan, loan.getOffice(), LoanTransactionType.REAMORTIZE,
+                transactionDate, txPrincipalAmount, txPrincipalAmount, ZERO, ZERO, ZERO, null, false, null, null);
+
+        final LoanReAmortizationParameter reAmortizationParameter = createReAmortizationParameterFromPreviewRequest(
+                reAmortizationTransaction, reAmortizationPreviewRequest);
+        reAmortizationTransaction.setLoanReAmortizationParameter(reAmortizationParameter);
+
+        return reAmortizationTransaction;
+    }
+
     private LoanReAmortizationParameter createReAmortizationParameter(LoanTransaction reAmortizationTransaction, JsonCommand command) {
         LoanReAmortizationInterestHandlingType reAmortizationInterestHandlingType = command.enumValueOfParameterNamed(
                 LoanReAmortizationApiConstants.reAmortizationInterestHandlingParamName, LoanReAmortizationInterestHandlingType.class);
@@ -179,10 +241,22 @@ public class LoanReAmortizationService {
         return new LoanReAmortizationParameter(reAmortizationTransaction, reAmortizationInterestHandlingType, reasonCodeValue);
     }
 
-    private void processReAmortizationTransaction(final Loan loan, final LoanTransaction reAmortizationTransaction) {
+    private LoanReAmortizationParameter createReAmortizationParameterFromPreviewRequest(final LoanTransaction reAmortizationTransaction,
+            final ReAmortizationPreviewRequest reAmortizationPreviewRequest) {
+        final LoanReAmortizationInterestHandlingType reAmortizationInterestHandlingType = LoanReAmortizationInterestHandlingType
+                .valueOf(reAmortizationPreviewRequest.getReAmortizationInterestHandling());
+        return new LoanReAmortizationParameter(reAmortizationTransaction, reAmortizationInterestHandlingType, null);
+    }
+
+    private void processReAmortizationTransaction(final Loan loan, final LoanTransaction reAmortizationTransaction,
+            final boolean withPostTransactionChecks) {
         if (loan.isInterestBearingAndInterestRecalculationEnabled()) {
             loanScheduleService.regenerateRepaymentSchedule(loan);
-            reprocessLoanTransactionsService.reprocessTransactions(loan, List.of(reAmortizationTransaction));
+            if (withPostTransactionChecks) {
+                reprocessLoanTransactionsService.reprocessTransactions(loan, List.of(reAmortizationTransaction));
+            } else {
+                reprocessLoanTransactionsService.reprocessTransactionsWithoutChecks(loan, List.of(reAmortizationTransaction));
+            }
         } else {
             reprocessLoanTransactionsService.processLatestTransaction(reAmortizationTransaction, loan);
         }

fineract-provider/src/main/java/org/apache/fineract/portfolio/loanaccount/service/reamortization/LoanReAmortizationValidator.java

@@ -54,6 +54,10 @@ public class LoanReAmortizationValidator {
         validateReAmortizeBusinessRules(loan);
     }
 
+    public void validateReAmortize(final Loan loan) {
+        validateReAmortizeBusinessRules(loan);
+    }
+
     private void validateReAmortizeRequest(JsonCommand command) {
         List<ApiParameterError> dataValidationErrors = new ArrayList<>();
         DataValidatorBuilder baseDataValidator = new DataValidatorBuilder(dataValidationErrors).resource("loan.reAmortization");