FINERACT-2042 Configurable CreditAllocations for Loan Product

fineract-loan/src/main/java/org/apache/fineract/portfolio/loanproduct/domain/AllocationType.java

@@ -18,9 +18,24 @@
  */
 package org.apache.fineract.portfolio.loanproduct.domain;
 
+import java.util.Arrays;
+import java.util.List;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import org.apache.fineract.infrastructure.core.data.EnumOptionData;
+
+@RequiredArgsConstructor
+@Getter
 public enum AllocationType {
-    PENALTY, //
-    FEE, //
-    PRINCIPAL, //
-    INTEREST //
+
+    PENALTY("Penalty"), //
+    FEE("Fee"), //
+    PRINCIPAL("Principal"), //
+    INTEREST("Interest"); //
+
+    private final String humanReadableName;
+
+    public static List<EnumOptionData> getValuesAsEnumOptionDataList() {
+        return Arrays.stream(values()).map(v -> new EnumOptionData((long) (v.ordinal() + 1), v.name(), v.getHumanReadableName())).toList();
+    }
 }

fineract-loan/src/main/java/org/apache/fineract/portfolio/loanproduct/domain/CreditAllocationsJsonParser.java

@@ -0,0 +1,110 @@
+/**
+ * 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.loanproduct.domain;
+
+import com.google.common.base.Enums;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import java.util.Comparator;
+import java.util.List;
+import java.util.Map;
+import lombok.AllArgsConstructor;
+import org.apache.commons.lang3.tuple.Pair;
+import org.apache.fineract.infrastructure.core.api.JsonCommand;
+import org.jetbrains.annotations.NotNull;
+import org.springframework.stereotype.Service;
+
+@Service
+@AllArgsConstructor
+public class CreditAllocationsJsonParser {
+
+    public final CreditAllocationsValidator creditAllocationsValidator;
+
+    public List<LoanProductCreditAllocationRule> assembleLoanProductCreditAllocationRules(final JsonCommand command,
+            String loanTransactionProcessingStrategyCode) {
+        JsonArray creditAllocation = command.arrayOfParameterNamed("creditAllocation");
+        List<LoanProductCreditAllocationRule> productCreditAllocationRules = null;
+        if (creditAllocation != null) {
+            productCreditAllocationRules = creditAllocation.asList().stream().map(json -> {
+                Map<String, JsonElement> map = json.getAsJsonObject().asMap();
+                LoanProductCreditAllocationRule creditAllocationRule = new LoanProductCreditAllocationRule();
+                populateCreditAllocationRules(map, creditAllocationRule);
+                populateTransactionType(map, creditAllocationRule);
+                return creditAllocationRule;
+            }).toList();
+        }
+        creditAllocationsValidator.validate(productCreditAllocationRules, loanTransactionProcessingStrategyCode);
+        return productCreditAllocationRules;
+    }
+
+    private void populateCreditAllocationRules(Map<String, JsonElement> map, LoanProductCreditAllocationRule creditAllocationRule) {
+        JsonArray creditAllocationOrder = asJsonArrayOrNull(map.get("creditAllocationOrder"));
+        if (creditAllocationOrder != null) {
+            creditAllocationRule.setAllocationTypes(getAllocationTypes(creditAllocationOrder));
+        }
+    }
+
+    private void populateTransactionType(Map<String, JsonElement> map, LoanProductCreditAllocationRule creditAllocationRule) {
+        String transactionType = asStringOrNull(map.get("transactionType"));
+        if (transactionType != null) {
+            creditAllocationRule.setTransactionType(Enums.getIfPresent(CreditAllocationTransactionType.class, transactionType).orNull());
+        }
+    }
+
+    @NotNull
+    private List<AllocationType> getAllocationTypes(JsonArray allocationOrder) {
+        if (allocationOrder != null) {
+            List<Pair<Integer, AllocationType>> parsedListWithOrder = allocationOrder.asList().stream().map(json -> {
+                Map<String, JsonElement> map = json.getAsJsonObject().asMap();
+                AllocationType allocationType = null;
+                String creditAllocationRule = asStringOrNull(map.get("creditAllocationRule"));
+                if (creditAllocationRule != null) {
+                    allocationType = Enums.getIfPresent(AllocationType.class, creditAllocationRule).orNull();
+                }
+                return Pair.of(asIntegerOrNull(map.get("order")), allocationType);
+            }).sorted(Comparator.comparing(Pair::getLeft)).toList();
+            creditAllocationsValidator.validatePairOfOrderAndCreditAllocationType(parsedListWithOrder);
+            return parsedListWithOrder.stream().map(Pair::getRight).toList();
+        } else {
+            return List.of();
+        }
+    }
+
+    private Integer asIntegerOrNull(JsonElement element) {
+        if (!element.isJsonNull()) {
+            return element.getAsInt();
+        }
+        return null;
+    }
+
+    private String asStringOrNull(JsonElement element) {
+        if (!element.isJsonNull()) {
+            return element.getAsString();
+        }
+        return null;
+    }
+
+    private JsonArray asJsonArrayOrNull(JsonElement element) {
+        if (!element.isJsonNull()) {
+            return element.getAsJsonArray();
+        }
+        return null;
+    }
+
+}

fineract-loan/src/main/java/org/apache/fineract/portfolio/loanproduct/domain/CreditAllocationsValidator.java

@@ -0,0 +1,96 @@
+/**
+ * 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.loanproduct.domain;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.IntStream;
+import org.apache.commons.lang3.tuple.Pair;
+import org.apache.fineract.infrastructure.core.data.ApiParameterError;
+import org.apache.fineract.infrastructure.core.exception.PlatformApiDataValidationException;
+import org.springframework.stereotype.Service;
+
+@Service
+public class CreditAllocationsValidator {
+
+    public static final String ADVANCED_PAYMENT_ALLOCATION_STRATEGY = "advanced-payment-allocation-strategy";
+
+    public void validate(List<LoanProductCreditAllocationRule> rules, String code) {
+        if (isAdvancedPaymentStrategy(code)) {
+            if (hasDuplicateTransactionTypes(rules)) {
+                raiseValidationError("advanced-payment-strategy-with-duplicate-credit-allocation",
+                        "The same transaction type must be provided only once");
+            }
+
+            if (rules != null) {
+                for (LoanProductCreditAllocationRule rule : rules) {
+                    validateAllocationRule(rule);
+                }
+            }
+
+        } else {
+            if (hasLoanProductCreditAllocationRule(rules)) {
+                raiseValidationError("credit_allocation.must.not.be.provided.when.allocation.strategy.is.not.advanced-payment-strategy",
+                        "In case '" + code + "' payment strategy, creditAllocation must not be provided");
+            }
+        }
+    }
+
+    public void validatePairOfOrderAndCreditAllocationType(List<Pair<Integer, AllocationType>> rules) {
+        if (rules.size() != 4) {
+            raiseValidationError("advanced-payment-strategy.each_credit_allocation_order.must.contain.4.entries",
+                    "Each provided credit allocation must contain exactly 4 allocation rules, but " + rules.size() + " were provided");
+        }
+
+        List<AllocationType> deduped = rules.stream().map(Pair::getRight).distinct().toList();
+        if (deduped.size() != 4) {
+            raiseValidationError("advanced-payment-strategy.must.not.have.duplicate.credit.allocation.rule",
+                    "The list of provided credit allocation rules must not contain any duplicates");
+        }
+
+        if (!Arrays.equals(IntStream.rangeClosed(1, 4).boxed().toArray(), rules.stream().map(Pair::getLeft).toArray())) {
+            raiseValidationError("advanced-payment-strategy.invalid.order", "The provided orders must be between 1 and 4");
+        }
+    }
+
+    private boolean hasDuplicateTransactionTypes(List<LoanProductCreditAllocationRule> rules) {
+        return rules != null
+                && rules.stream().map(LoanProductCreditAllocationRule::getTransactionType).distinct().toList().size() != rules.size();
+    }
+
+    private void validateAllocationRule(LoanProductCreditAllocationRule rule) {
+        if (rule.getTransactionType() == null) {
+            raiseValidationError("advanced-payment-strategy.with.not.valid.transaction.type",
+                    "Credit allocation was provided with a not valid transaction type");
+        }
+    }
+
+    private boolean isAdvancedPaymentStrategy(String code) {
+        return ADVANCED_PAYMENT_ALLOCATION_STRATEGY.equals(code);
+    }
+
+    private boolean hasLoanProductCreditAllocationRule(List<LoanProductCreditAllocationRule> rules) {
+        return rules != null && rules.size() > 0;
+    }
+
+    private void raiseValidationError(String globalisationMessageCode, String msg) {
+        throw new PlatformApiDataValidationException(List.of(ApiParameterError.generalError(globalisationMessageCode, msg)));
+    }
+
+}

fineract-loan/src/main/java/org/apache/fineract/portfolio/loanproduct/domain/LoanProduct.java

@@ -675,6 +675,13 @@ public class LoanProduct extends AbstractPersistableCustom {
             }
         }
 
+        this.creditAllocationRules = creditAllocationRules;
+        if (this.creditAllocationRules != null) {
+            for (LoanProductCreditAllocationRule loanProductCreditAllocationRule : this.creditAllocationRules) {
+                loanProductCreditAllocationRule.setLoanProduct(this);
+            }
+        }
+
         this.name = name.trim();
         this.shortName = shortName.trim();
         if (StringUtils.isNotBlank(description)) {
@@ -773,6 +780,13 @@ public class LoanProduct extends AbstractPersistableCustom {
                     "In case '" + transactionProcessingStrategyCode + "' payment strategy, payment_allocation must not be provided");
         }
 
+        if (this.creditAllocationRules != null && creditAllocationRules.size() > 0
+                && !transactionProcessingStrategyCode.equals("advanced-payment-allocation-strategy")) {
+            throw new LoanProductGeneralRuleException(
+                    "creditAllocation.must.not.be.provided.when.allocation.strategy.is.not.advanced-payment-strategy",
+                    "In case '" + transactionProcessingStrategyCode + "' payment strategy, creditAllocation must not be provided");
+        }
+
         if (this.disallowExpectedDisbursements) {
             if (!this.isMultiDisburseLoan()) {
                 throw new LoanProductGeneralRuleException("allowMultipleDisbursals.not.set.disallowExpectedDisbursements.cant.be.set",
@@ -906,6 +920,10 @@ public class LoanProduct extends AbstractPersistableCustom {
         return this.paymentAllocationRules;
     }
 
+    public List<LoanProductCreditAllocationRule> getCreditAllocationRules() {
+        return this.creditAllocationRules;
+    }
+
     public void update(final LoanProductConfigurableAttributes loanConfigurableAttributes) {
         this.loanConfigurableAttributes = loanConfigurableAttributes;
     }
@@ -999,6 +1017,14 @@ public class LoanProduct extends AbstractPersistableCustom {
             }
         }
 
+        final String creditAllocationParamName = "creditAllocation";
+        if (command.hasParameter(creditAllocationParamName)) {
+            final JsonArray jsonArray = command.arrayOfParameterNamed(creditAllocationParamName);
+            if (jsonArray != null) {
+                actualChanges.put(creditAllocationParamName, command.jsonFragment(creditAllocationParamName));
+            }
+        }
+
         final String chargesParamName = "charges";
         if (command.hasParameter(chargesParamName)) {
             final JsonArray jsonArray = command.arrayOfParameterNamed(chargesParamName);