/*

  * Copyright 2007-2008 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.rice.kns.service.impl;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.HashMap;

 import java.util.Iterator;

 import java.util.Map;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.kns.bo.BusinessObject;

 import org.kuali.rice.kns.bo.BusinessObjectRelationship;

 import org.kuali.rice.kns.bo.Inactivateable;

 import org.kuali.rice.kns.datadictionary.InactivationBlockingMetadata;

 import org.kuali.rice.kns.service.BusinessObjectMetaDataService;

 import org.kuali.rice.kns.service.BusinessObjectService;

 import org.kuali.rice.kns.service.InactivationBlockingDetectionService;

 import org.kuali.rice.kns.util.ObjectUtils;

 import org.springframework.transaction.annotation.Transactional;

 /**

  * Performs checking of inactivation blocking 

  * 

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 @Transactional

 public class InactivationBlockingDetectionServiceImpl implements InactivationBlockingDetectionService {

     private static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(InactivationBlockingDetectionServiceImpl.class);

     protected BusinessObjectMetaDataService businessObjectMetaDataService;

     protected BusinessObjectService businessObjectService;

     /**

      * Note we are checking the active getting after retrieving potential blocking records instead of setting criteria on the

          * active field. This is because some implementations of {@link Inactivateable} might not have the active field, for example

          * instances of {@link InactivateableFromTo}

          * 

      * @see org.kuali.rice.kns.service.InactivationBlockingDetectionService#listAllBlockerRecords(org.kuali.rice.kns.datadictionary.InactivationBlockingDefinition)

      * @see org.kuali.rice.kns.bo.Inactivateable

      */

     @SuppressWarnings("unchecked")

         public Collection<BusinessObject> listAllBlockerRecords(BusinessObject blockedBo, InactivationBlockingMetadata inactivationBlockingMetadata) {

                 Collection<BusinessObject> blockingRecords = new ArrayList<BusinessObject>();

                 Map<String, String> queryMap = buildInactivationBlockerQueryMap(blockedBo, inactivationBlockingMetadata);

                 if (LOG.isDebugEnabled()) {

                         LOG.debug("Checking for blocker records for object: " + blockedBo);

                         LOG.debug("    With Metadata: " + inactivationBlockingMetadata);

                         LOG.debug("    Resulting Query Map: " + queryMap);

                 }

                 if (queryMap != null) {

                         Collection potentialBlockingRecords = businessObjectService.findMatching(

                                         inactivationBlockingMetadata.getBlockingReferenceBusinessObjectClass(), queryMap);

                         for (Iterator iterator = potentialBlockingRecords.iterator(); iterator.hasNext();) {

                                 Inactivateable businessObject = (Inactivateable) iterator.next();

                                 if (businessObject.isActive()) {

                                         blockingRecords.add((BusinessObject) businessObject);

                                 }

                         }

                 }

                 return blockingRecords;

         }

         /**

          * Note we are checking the active getting after retrieving potential blocking records instead of setting criteria on the

          * active field. This is because some implementations of {@link Inactivateable} might not have the active field, for example

          * instances of {@link InactivateableFromTo}

          * 

          * @see org.kuali.rice.kns.service.InactivationBlockingDetectionService#hasABlockingRecord(org.kuali.rice.kns.bo.BusinessObject,

          *      org.kuali.rice.kns.datadictionary.InactivationBlockingMetadata)

          * @see org.kuali.rice.kns.bo.Inactivateable

          */

         public boolean hasABlockingRecord(BusinessObject blockedBo, InactivationBlockingMetadata inactivationBlockingMetadata) {

                 boolean hasBlockingRecord = false;

                 Map<String, String> queryMap = buildInactivationBlockerQueryMap(blockedBo, inactivationBlockingMetadata);

                 if (queryMap != null) {

                         Collection potentialBlockingRecords = businessObjectService.findMatching(

                                         inactivationBlockingMetadata.getBlockingReferenceBusinessObjectClass(), queryMap);

                         for (Iterator iterator = potentialBlockingRecords.iterator(); iterator.hasNext();) {

                                 Inactivateable businessObject = (Inactivateable) iterator.next();

                                 if (businessObject.isActive()) {

                                         hasBlockingRecord = true;

                                         break;

                                 }

                         }

                 }

                 // if queryMap were null, means that we couldn't perform a query, and hence, need to return false

                 return hasBlockingRecord;

         }

         protected Map<String, String> buildInactivationBlockerQueryMap(BusinessObject blockedBo, InactivationBlockingMetadata inactivationBlockingMetadata) {

                 BusinessObject blockingBo = (BusinessObject) ObjectUtils.createNewObjectFromClass(inactivationBlockingMetadata

                                 .getBlockingReferenceBusinessObjectClass());

                 BusinessObjectRelationship businessObjectRelationship = businessObjectMetaDataService

                                 .getBusinessObjectRelationship(blockingBo,

                                                 inactivationBlockingMetadata.getBlockedReferencePropertyName());

                 // note, this method assumes that all PK fields of the blockedBo have a non-null and, for strings, non-blank values

                 if (businessObjectRelationship != null) {

                         Map<String, String> parentToChildReferences = businessObjectRelationship.getParentToChildReferences();

                         Map<String, String> queryMap = new HashMap<String, String>();

                         for (Map.Entry<String, String> parentToChildReference : parentToChildReferences.entrySet()) {

                                 String fieldName = parentToChildReference.getKey();

                                 Object fieldValue = ObjectUtils.getPropertyValue(blockedBo, parentToChildReference.getValue());

                                 if (fieldValue != null && StringUtils.isNotBlank(fieldValue.toString())) {

                                         queryMap.put(fieldName, fieldValue.toString());

                                 } else {

                                         LOG.error("Found null value for foreign key field " + fieldName

                                                         + " while building inactivation blocking query map.");

                                         throw new RuntimeException("Found null value for foreign key field '" + fieldName

                                                         + "' while building inactivation blocking query map.");

                                 }

                         }

                         return queryMap;

                 }

                 return null;

         }

     public void setBusinessObjectMetaDataService(BusinessObjectMetaDataService businessObjectMetaDataService) {

         this.businessObjectMetaDataService = businessObjectMetaDataService;

     }

     public void setBusinessObjectService(BusinessObjectService businessObjectService) {

         this.businessObjectService = businessObjectService;

     }

 }