/*
    * Copyright 2008 The Kuali Foundation
    * 
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    * 
   * 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.kuali.ole.sys.document.validation.impl;
  
  import java.util.List;
  
  import org.kuali.ole.sys.OLEConstants;
  import org.kuali.ole.sys.OLEKeyConstants;
  import org.kuali.ole.sys.businessobject.GeneralLedgerPendingEntry;
  import org.kuali.ole.sys.context.SpringContext;
  import org.kuali.ole.sys.document.AccountingDocument;
  import org.kuali.ole.sys.document.validation.GenericValidation;
  import org.kuali.ole.sys.document.validation.event.AttributedDocumentEvent;
  import org.kuali.ole.sys.service.GeneralLedgerPendingEntryService;
  import org.kuali.rice.core.api.util.type.KualiDecimal;
  import org.kuali.rice.krad.exception.ValidationException;
  import org.kuali.rice.krad.util.GlobalVariables;
  
  /**
   * A validation that checks that the credits and debits of GLPEs generated by a document are balanced.
   */
  public class DebitsAndCreditsBalanceValidation extends GenericValidation {
      private static org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(DebitsAndCreditsBalanceValidation.class);
      
      private AccountingDocument accountingDocumentForValidation;
      
      /**
       * Generates the GLPEs for a given accounting document and checks that the debits total equals
       * the credits total.
       * <strong>Expects the document to be sent in as a property.</strong>
       * @see org.kuali.ole.sys.document.validation.GenericValidation#validate(java.lang.Object[])
       */
      public boolean validate(AttributedDocumentEvent event) {
          LOG.debug("Validation started");
          
          // generate GLPEs specifically here so that we can compare debits to credits
          if (!SpringContext.getBean(GeneralLedgerPendingEntryService.class).generateGeneralLedgerPendingEntries(accountingDocumentForValidation)) {
              throw new ValidationException("general ledger GLPE generation failed");
          }
  
          // now loop through all of the GLPEs and calculate buckets for debits and credits
          KualiDecimal creditAmount = KualiDecimal.ZERO;
          KualiDecimal debitAmount = KualiDecimal.ZERO;
          
          List<GeneralLedgerPendingEntry> pendingEntries = accountingDocumentForValidation.getGeneralLedgerPendingEntries();
          for(GeneralLedgerPendingEntry entry : pendingEntries) {
              if(entry.isTransactionEntryOffsetIndicator()) {
                  continue;
              }
              
              if (OLEConstants.GL_CREDIT_CODE.equals(entry.getTransactionDebitCreditCode())) {
                  creditAmount = creditAmount.add(entry.getTransactionLedgerEntryAmount());
              }
              else {
                  debitAmount = debitAmount.add(entry.getTransactionLedgerEntryAmount());
              }           
          }
          
          boolean isValid = debitAmount.compareTo(creditAmount) == 0;
  
          if (!isValid) {
              GlobalVariables.getMessageMap().putError(OLEConstants.ACCOUNTING_LINE_ERRORS, OLEKeyConstants.ERROR_DOCUMENT_BALANCE);
          }
          
          return isValid;
      }
  
      /**
       * Gets the accountingDocumentForValidation attribute. 
       * @return Returns the accountingDocumentForValidation.
       */
      public AccountingDocument getAccountingDocumentForValidation() {
          return accountingDocumentForValidation;
      }
  
      /**
       * Sets the accountingDocumentForValidation attribute value.
       * @param accountingDocumentForValidation The accountingDocumentForValidation to set.
       */
      public void setAccountingDocumentForValidation(AccountingDocument accountingDocumentForValidation) {
          this.accountingDocumentForValidation = accountingDocumentForValidation;
      }
  }