/*
    * The Kuali Financial System, a comprehensive financial management system for higher education.
    * 
    * Copyright 2005-2014 The Kuali Foundation
    * 
    * This program is free software: you can redistribute it and/or modify
    * it under the terms of the GNU Affero General Public License as
    * published by the Free Software Foundation, either version 3 of the
    * License, or (at your option) any later version.
   * 
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU Affero General Public License for more details.
   * 
   * You should have received a copy of the GNU Affero General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  package org.kuali.kfs.module.ar.document.validation.impl;
  
  import java.math.BigDecimal;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.kfs.module.ar.ArConstants;
  import org.kuali.kfs.module.ar.ArKeyConstants;
  import org.kuali.kfs.module.ar.ArPropertyConstants;
  import org.kuali.kfs.module.ar.businessobject.CustomerCreditMemoDetail;
  import org.kuali.kfs.module.ar.document.CustomerCreditMemoDocument;
  import org.kuali.kfs.module.ar.document.CustomerInvoiceDocument;
  import org.kuali.kfs.module.ar.document.service.CustomerInvoiceDocumentService;
  import org.kuali.kfs.module.ar.document.validation.ContinueCustomerCreditMemoDocumentRule;
  import org.kuali.kfs.module.ar.document.validation.RecalculateCustomerCreditMemoDetailRule;
  import org.kuali.kfs.module.ar.document.validation.RecalculateCustomerCreditMemoDocumentRule;
  import org.kuali.kfs.sys.KFSConstants;
  import org.kuali.kfs.sys.businessobject.GeneralLedgerPendingEntry;
  import org.kuali.kfs.sys.context.SpringContext;
  import org.kuali.rice.core.api.util.type.KualiDecimal;
  import org.kuali.rice.kew.api.WorkflowDocument;
  import org.kuali.rice.kew.api.WorkflowDocumentFactory;
  import org.kuali.rice.kns.rules.TransactionalDocumentRuleBase;
  import org.kuali.rice.krad.document.Document;
  import org.kuali.rice.krad.document.TransactionalDocument;
  import org.kuali.rice.krad.service.BusinessObjectService;
  import org.kuali.rice.krad.util.GlobalVariables;
  import org.kuali.rice.krad.util.KRADConstants;
  import org.kuali.rice.krad.util.ObjectUtils;
  
  /**
   * This class holds the business rules for the AR Credit Memo Document
   */
  
  public class CustomerCreditMemoDocumentRule extends TransactionalDocumentRuleBase implements RecalculateCustomerCreditMemoDetailRule<TransactionalDocument>, RecalculateCustomerCreditMemoDocumentRule<TransactionalDocument>, ContinueCustomerCreditMemoDocumentRule<TransactionalDocument> {
  
      protected static final BigDecimal ALLOWED_QTY_DEVIATION = new BigDecimal("0.10");
  
      public CustomerCreditMemoDocumentRule() {
      }
  
      /**
       * @see org.kuali.rice.krad.rules.DocumentRuleBase#processCustomSaveDocumentBusinessRules(org.kuali.rice.krad.document.Document)
       */
      @Override
      protected boolean processCustomSaveDocumentBusinessRules(Document document) {
          boolean isValid = super.processCustomSaveDocumentBusinessRules(document);
  
          GlobalVariables.getMessageMap().addToErrorPath(KRADConstants.DOCUMENT_PROPERTY_NAME);
          isValid &= processRecalculateCustomerCreditMemoDocumentRules((TransactionalDocument) document, true);
          GlobalVariables.getMessageMap().removeFromErrorPath(KRADConstants.DOCUMENT_PROPERTY_NAME);
  
          return isValid;
      }
  
      /**
       * @see org.kuali.kfs.module.ar.document.validation.RecalculateCustomerCreditMemoDetailRule#processRecalculateCustomerCreditMemoDetailRules(org.kuali.kfs.sys.document.AccountingDocument,
       *      org.kuali.kfs.module.ar.businessobject.CustomerCreditMemoDetail)
       */
      @Override
      public boolean processRecalculateCustomerCreditMemoDetailRules(TransactionalDocument document, CustomerCreditMemoDetail customerCreditMemoDetail) {
          boolean success = true;
  
          CustomerCreditMemoDocument customerCreditMemoDocument = (CustomerCreditMemoDocument) document;
          customerCreditMemoDocument.refreshReferenceObject("invoice");
          String inputKey = isQtyOrItemAmountEntered(customerCreditMemoDetail);
  
          // refresh InvoiceOpenItemAmount and InvoiceOpenAmountQuantity if changed by any other transaction
          customerCreditMemoDetail.setInvoiceOpenItemAmount(customerCreditMemoDetail.getCustomerInvoiceDetail().getAmountOpen());
          customerCreditMemoDetail.setInvoiceOpenItemQuantity(customerCreditMemoDocument.getInvoiceOpenItemQuantity(customerCreditMemoDetail, customerCreditMemoDetail.getCustomerInvoiceDetail()));
  
          // 'Qty' was entered
          if (StringUtils.equals(ArConstants.CustomerCreditMemoConstants.CUSTOMER_CREDIT_MEMO_ITEM_QUANTITY, inputKey)) {
              success &= isValueGreaterThanZero(customerCreditMemoDetail.getCreditMemoItemQuantity());
              success &= isCustomerCreditMemoQtyLessThanEqualToInvoiceOpenQty(customerCreditMemoDetail);
          }
          // 'Item Amount' was entered
          else if (StringUtils.equals(ArConstants.CustomerCreditMemoConstants.CUSTOMER_CREDIT_MEMO_ITEM_TOTAL_AMOUNT, inputKey)) {
             success &= isValueGreaterThanZero(customerCreditMemoDetail.getCreditMemoItemTotalAmount());
             success &= isCustomerCreditMemoItemAmountLessThanEqualToInvoiceOpenItemAmount(customerCreditMemoDocument, customerCreditMemoDetail);
         }
         // both 'Qty' and 'Item Amount' were entered -> validate
         else if (StringUtils.equals(ArConstants.CustomerCreditMemoConstants.BOTH_QUANTITY_AND_ITEM_TOTAL_AMOUNT_ENTERED, inputKey)) {
             success &= isValueGreaterThanZero(customerCreditMemoDetail.getCreditMemoItemTotalAmount());
             success &= isCustomerCreditMemoItemAmountLessThanEqualToInvoiceOpenItemAmount(customerCreditMemoDocument, customerCreditMemoDetail);
             success &= isValueGreaterThanZero(customerCreditMemoDetail.getCreditMemoItemQuantity());
             success &= isCustomerCreditMemoQtyLessThanEqualToInvoiceOpenQty(customerCreditMemoDetail);
             success &= checkIfCustomerCreditMemoQtyAndCustomerCreditMemoItemAmountValid(customerCreditMemoDetail, customerCreditMemoDetail.getCustomerInvoiceDetail().getInvoiceItemUnitPrice());
         }
         // if there is no input -> wrong input
         else {
             success = false;
         }
         return success;
     }
 
     public String isQtyOrItemAmountEntered(CustomerCreditMemoDetail customerCreditMemoDetail) {
 
         BigDecimal customerCreditMemoItemQty = customerCreditMemoDetail.getCreditMemoItemQuantity();
         KualiDecimal customerCreditMemoItemAmount = customerCreditMemoDetail.getCreditMemoItemTotalAmount();
         String inputKey = "";
 
         if (ObjectUtils.isNotNull(customerCreditMemoItemQty) && ObjectUtils.isNotNull(customerCreditMemoItemAmount)) {
             inputKey = ArConstants.CustomerCreditMemoConstants.BOTH_QUANTITY_AND_ITEM_TOTAL_AMOUNT_ENTERED;
         }
         else if (ObjectUtils.isNotNull(customerCreditMemoItemQty)) {
             inputKey = ArConstants.CustomerCreditMemoConstants.CUSTOMER_CREDIT_MEMO_ITEM_QUANTITY;
         }
         else if (ObjectUtils.isNotNull(customerCreditMemoItemAmount)) {
             inputKey = ArConstants.CustomerCreditMemoConstants.CUSTOMER_CREDIT_MEMO_ITEM_TOTAL_AMOUNT;
         }
 
         return inputKey;
     }
 
     public boolean isValueGreaterThanZero(BigDecimal value) {
         boolean validValue = (value.compareTo(BigDecimal.ZERO) == 1 ? true : false);
         if (!validValue) {
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_ITEM_QUANTITY, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DETAIL_ITEM_QUANTITY_LESS_THAN_OR_EQUAL_TO_ZERO);
         }
         return validValue;
     }
 
     public boolean isValueGreaterThanZero(KualiDecimal value) {
         boolean validValue = value.isPositive();
         if (!validValue) {
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_ITEM_TOTAL_AMOUNT, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DETAIL_ITEM_AMOUNT_LESS_THAN_OR_EQUAL_TO_ZERO);
         }
         return validValue;
     }
 
     public boolean isCustomerCreditMemoItemAmountLessThanEqualToInvoiceOpenItemAmount(CustomerCreditMemoDocument customerCreditMemoDocument, CustomerCreditMemoDetail customerCreditMemoDetail) {
 
         KualiDecimal invoiceOpenItemAmount = customerCreditMemoDetail.getInvoiceOpenItemAmount();
         KualiDecimal creditMemoItemAmount = customerCreditMemoDetail.getCreditMemoItemTotalAmount();
 
         boolean validItemAmount = creditMemoItemAmount.isLessEqual(invoiceOpenItemAmount);
         if (!validItemAmount) {
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_ITEM_TOTAL_AMOUNT, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DETAIL_ITEM_AMOUNT_GREATER_THAN_INVOICE_ITEM_AMOUNT);
         }
 
         return validItemAmount;
     }
 
     public boolean isCustomerCreditMemoQtyLessThanEqualToInvoiceOpenQty(CustomerCreditMemoDetail customerCreditMemoDetail) {
         BigDecimal invoiceOpenItemQty = customerCreditMemoDetail.getInvoiceOpenItemQuantity();
         BigDecimal customerCreditMemoItemQty = customerCreditMemoDetail.getCreditMemoItemQuantity();
 
         // customer credit memo quantity must not be greater than invoice open item quantity
         boolean validQuantity = (customerCreditMemoItemQty.compareTo(invoiceOpenItemQty) < 1 ? true : false);
         if (!validQuantity) {
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_ITEM_QUANTITY, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DETAIL_ITEM_QUANTITY_GREATER_THAN_INVOICE_ITEM_QUANTITY);
         }
 
         return validQuantity;
     }
 
     public boolean checkIfCustomerCreditMemoQtyAndCustomerCreditMemoItemAmountValid(CustomerCreditMemoDetail customerCreditMemoDetail, BigDecimal unitPrice) {
         KualiDecimal creditAmount = customerCreditMemoDetail.getCreditMemoItemTotalAmount();
         BigDecimal creditQuantity = customerCreditMemoDetail.getCreditMemoItemQuantity();
 
         // if unit price is zero, leave this validation, as it will cause an exception below by attempting to divide by zero
         if (unitPrice.compareTo(BigDecimal.ZERO) == 0) {
             // no need to report error, because it is already recorded by another validation check.
             return false;
         }
 
         // determine the expected exact total credit memo quantity, based on actual credit amount entered
         BigDecimal expectedCreditQuantity = creditAmount.bigDecimalValue().divide(unitPrice, ArConstants.ITEM_QUANTITY_SCALE, BigDecimal.ROUND_HALF_UP);
 
         // return false if the expected quantity is 0 while the actual quantity is not
         if (expectedCreditQuantity.compareTo(BigDecimal.ZERO) == 0 && creditQuantity.compareTo(BigDecimal.ZERO) != 0) {
             return false;
         }
 
         // determine the deviation percentage that the actual creditQuantity has from expectedCreditQuantity
         BigDecimal deviationPercentage = creditQuantity.subtract(expectedCreditQuantity).divide(expectedCreditQuantity, ArConstants.ITEM_QUANTITY_SCALE, BigDecimal.ROUND_HALF_UP).abs();
 
         // only allow a certain deviation of creditQuantity from the expectedCreditQuantity
         boolean validFlag = deviationPercentage.compareTo(ALLOWED_QTY_DEVIATION) < 1;
 
         if (!validFlag) {
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_ITEM_QUANTITY, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DETAIL_INVALID_DATA_INPUT);
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_ITEM_TOTAL_AMOUNT, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DETAIL_INVALID_DATA_INPUT);
         }
         return validFlag;
     }
 
     /**
      * @see org.kuali.kfs.module.ar.document.validation.RecalculateCustomerCreditMemoDocumentRule#processRecalculateCustomerCreditMemoDocumentRules(org.kuali.kfs.sys.document.AccountingDocument)
      */
     @Override
     public boolean processRecalculateCustomerCreditMemoDocumentRules(TransactionalDocument document, boolean printErrMsgFlag) {
         boolean success = true;
         boolean crmDataEnteredFlag = false;
         CustomerCreditMemoDocument customerCreditMemoDocument = (CustomerCreditMemoDocument) document;
         List<CustomerCreditMemoDetail> customerCreditMemoDetails = customerCreditMemoDocument.getCreditMemoDetails();
         int i = 0;
         String propertyName;
 
         for (CustomerCreditMemoDetail customerCreditMemoDetail : customerCreditMemoDetails) {
             propertyName = KFSConstants.CUSTOMER_CREDIT_MEMO_DETAIL_PROPERTY_NAME + "[" + i + "]";
             GlobalVariables.getMessageMap().addToErrorPath(propertyName);
 
             // validate only if there is input data
             if (!isQtyOrItemAmountEntered(customerCreditMemoDetail).equals(StringUtils.EMPTY)) {
                 crmDataEnteredFlag = true;
                 success &= processRecalculateCustomerCreditMemoDetailRules(customerCreditMemoDocument, customerCreditMemoDetail);
             }
             GlobalVariables.getMessageMap().removeFromErrorPath(propertyName);
             i++;
         }
 
         success &= crmDataEnteredFlag;
 
         // print error message if 'Submit'/'Save'/'Blanket Approved' button is pressed and there is no CRM data entered
         if (!crmDataEnteredFlag && printErrMsgFlag) {
             GlobalVariables.getMessageMap().putError(KFSConstants.DOCUMENT_PROPERTY_NAME, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DOCUMENT_NO_DATA_TO_SUBMIT);
         }
 
         return success;
     }
 
     /**
      * @see org.kuali.kfs.module.ar.document.validation.ContinueCustomerCreditMemoDocumentRule#processContinueCustomerCreditMemoDocumentRules(org.kuali.kfs.sys.document.AccountingDocument)
      */
     @Override
     public boolean processContinueCustomerCreditMemoDocumentRules(TransactionalDocument document) {
         boolean success;
         CustomerCreditMemoDocument customerCreditMemoDocument = (CustomerCreditMemoDocument) document;
 
         success = checkIfInvoiceNumberIsFinal(customerCreditMemoDocument.getFinancialDocumentReferenceInvoiceNumber());
         if (success) {
             success = checkIfThereIsNoAnotherCRMInRouteForTheInvoice(customerCreditMemoDocument.getFinancialDocumentReferenceInvoiceNumber());
         }
         if (success) {
             success = checkInvoiceForErrorCorrection(customerCreditMemoDocument.getFinancialDocumentReferenceInvoiceNumber());
         }
 
         return success;
     }
 
     public boolean checkIfInvoiceNumberIsFinal(String invDocumentNumber) {
         boolean success = true;
 
         if (StringUtils.isBlank(invDocumentNumber)) {
             success &= false;
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_DOCUMENT_REF_INVOICE_NUMBER, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DOCUMENT__INVOICE_DOCUMENT_NUMBER_IS_REQUIRED);
         }
         else {
             CustomerInvoiceDocumentService service = SpringContext.getBean(CustomerInvoiceDocumentService.class);
             CustomerInvoiceDocument customerInvoiceDocument = service.getInvoiceByInvoiceDocumentNumber(invDocumentNumber);
             if (ObjectUtils.isNull(customerInvoiceDocument)) {
                 success &= false;
                 GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_DOCUMENT_REF_INVOICE_NUMBER, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DOCUMENT_INVALID_INVOICE_DOCUMENT_NUMBER);
             }
             else if (!SpringContext.getBean(CustomerInvoiceDocumentService.class).checkIfInvoiceNumberIsFinal(invDocumentNumber)) {
                 GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_DOCUMENT_REF_INVOICE_NUMBER, ArKeyConstants.ERROR_CUSTOMER_INVOICE_DOCUMENT_NOT_FINAL);
                 success &= false;
             }
         }
         return success;
     }
 
     /**
      * This method checks if there is no another CRM in route for the invoice not in route if CRM status is one of the following:
      * processed, cancelled, or disapproved
      *
      * @param invoice
      * @return
      */
     public boolean checkIfThereIsNoAnotherCRMInRouteForTheInvoice(String invoiceDocumentNumber) {
 
         WorkflowDocument workflowDocument;
         boolean success = true;
 
         Map<String, String> fieldValues = new HashMap<String, String>();
         fieldValues.put("financialDocumentReferenceInvoiceNumber", invoiceDocumentNumber);
 
         BusinessObjectService businessObjectService = SpringContext.getBean(BusinessObjectService.class);
         Collection<CustomerCreditMemoDocument> customerCreditMemoDocuments = businessObjectService.findMatching(CustomerCreditMemoDocument.class, fieldValues);
 
         // no CRMs associated with the invoice are found
         if (customerCreditMemoDocuments.isEmpty()) {
             return success;
         }
 
         String userId = GlobalVariables.getUserSession().getPrincipalId();
         for(CustomerCreditMemoDocument customerCreditMemoDocument : customerCreditMemoDocuments) {
             workflowDocument = WorkflowDocumentFactory.loadDocument(userId, customerCreditMemoDocument.getDocumentNumber());
             if (!(workflowDocument.isApproved() || workflowDocument.isProcessed() || workflowDocument.isCanceled() || workflowDocument.isDisapproved())) {
                 GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_DOCUMENT_REF_INVOICE_NUMBER, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DOCUMENT_ONE_CRM_IN_ROUTE_PER_INVOICE);
                 success = false;
                 break;
             }
         }
         return success;
     }
 
     /**
      * This method checks if the Invoice has been error corrected or is an error correcting invoice
      *
      * @param invoice
      * @return
      */
     public boolean checkInvoiceForErrorCorrection(String invoiceDocumentNumber) {
         CustomerInvoiceDocumentService service = SpringContext.getBean(CustomerInvoiceDocumentService.class);
         CustomerInvoiceDocument customerInvoiceDocument = service.getInvoiceByInvoiceDocumentNumber(invoiceDocumentNumber);
 
         // invoice has been corrected
         if (customerInvoiceDocument.hasInvoiceBeenCorrected()) {
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_DOCUMENT_REF_INVOICE_NUMBER, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DOCUMENT_CORRECTED_INVOICE);
             return false;
         }
         // this is a correcting invoice
         if (customerInvoiceDocument.isInvoiceReversal()) {
             GlobalVariables.getMessageMap().putError(ArPropertyConstants.CustomerCreditMemoDocumentFields.CREDIT_MEMO_DOCUMENT_REF_INVOICE_NUMBER, ArKeyConstants.ERROR_CUSTOMER_CREDIT_MEMO_DOCUMENT_CORRECTING_INVOICE);
             return false;
         }
         return true;
     }
 
     @Override
     public boolean isDocumentAttributesValid(Document document, boolean validateRequired) {
         //refresh GLPE nonupdateable business object references....
         CustomerCreditMemoDocument customerCreditMemoDocument = (CustomerCreditMemoDocument) document;
 
         for (CustomerCreditMemoDetail customerDetail : customerCreditMemoDocument.getCreditMemoDetails()) {
             customerDetail.getCustomerInvoiceDetail().refreshNonUpdateableReferences();
         }
 
         for (GeneralLedgerPendingEntry glpe : customerCreditMemoDocument.getGeneralLedgerPendingEntries()) {
             glpe.refreshNonUpdateableReferences();
         }
 
         return super.isDocumentAttributesValid(document, validateRequired);
     }
 
 }