/*

  * Copyright 2005-2008 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.krad.service.impl;

 import java.beans.PropertyDescriptor;

 import java.lang.reflect.Field;

 import java.lang.reflect.InvocationTargetException;

 import java.util.HashSet;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 import java.util.Set;

 import org.apache.commons.beanutils.PropertyUtils;

 import org.apache.commons.lang.StringUtils;

 import org.apache.log4j.Logger;

 import org.kuali.rice.core.framework.persistence.jpa.metadata.EntityDescriptor;

 import org.kuali.rice.core.framework.persistence.jpa.metadata.MetadataManager;

 import org.kuali.rice.core.framework.persistence.jpa.metadata.ObjectDescriptor;

 import org.kuali.rice.krad.bo.PersistableBusinessObject;

 import org.kuali.rice.krad.dao.PersistenceDao;

 import org.kuali.rice.krad.exception.IntrospectionException;

 import org.kuali.rice.krad.exception.ObjectNotABusinessObjectRuntimeException;

 import org.kuali.rice.krad.exception.ReferenceAttributeDoesntExistException;

 import org.kuali.rice.krad.exception.ReferenceAttributeNotAnOjbReferenceException;

 import org.kuali.rice.krad.service.PersistenceService;

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

 import org.springframework.transaction.annotation.Transactional;

 /**

  * This class is the service implementation for the Persistence structure.

  */

 @Transactional

 public class PersistenceServiceJpaImpl extends PersistenceServiceImplBase implements PersistenceService {

         private static Logger LOG = Logger.getLogger(PersistenceServiceJpaImpl.class);

     private PersistenceDao persistenceDao;

     public void setPersistenceDao(PersistenceDao persistenceDao) {

         this.persistenceDao = persistenceDao;

     }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#allForeignKeyValuesPopulatedForReference(org.kuali.rice.krad.bo.PersistableBusinessObject, java.lang.String)

          */

         public boolean allForeignKeyValuesPopulatedForReference(PersistableBusinessObject bo, String referenceName) {

         boolean allFkeysHaveValues = true;

         // yelp if nulls were passed in

         if (bo == null) {

             throw new IllegalArgumentException("The Class passed in for the BusinessObject argument was null.");

         }

         if (StringUtils.isBlank(referenceName)) {

             throw new IllegalArgumentException("The String passed in for the referenceName argument was null or empty.");

         }

         PropertyDescriptor propertyDescriptor = null;

         // make sure the attribute exists at all, throw exception if not

         try {

             propertyDescriptor = PropertyUtils.getPropertyDescriptor(bo, referenceName);

                 } catch (Exception e) {

             throw new RuntimeException(e);

         }

         if (propertyDescriptor == null) {

             throw new ReferenceAttributeDoesntExistException("Requested attribute: '" + referenceName + "' does not exist " + "on class: '" + bo.getClass().getName() + "'.");

         }

         // get the class of the attribute name

         Class referenceClass = getBusinessObjectAttributeClass( bo.getClass(), referenceName );

         if ( referenceClass == null ) {

                 referenceClass = propertyDescriptor.getPropertyType();

         }

         // make sure the class of the attribute descends from BusinessObject,

         // otherwise throw an exception

         if (!PersistableBusinessObject.class.isAssignableFrom(referenceClass)) {

                         throw new ObjectNotABusinessObjectRuntimeException("Attribute requested (" + referenceName + ") is of class: " + "'" + referenceClass.getName() + "' and is not a " + "descendent of BusinessObject.  Only descendents of BusinessObject " + "can be used.");

         }

         EntityDescriptor descriptor = MetadataManager.getEntityDescriptor(bo.getClass());

             ObjectDescriptor objectDescriptor = descriptor.getObjectDescriptorByName(referenceName);

         if (objectDescriptor == null) {

             throw new ReferenceAttributeNotAnOjbReferenceException("Attribute requested (" + referenceName + ") is not listed " + "in OJB as a reference-descriptor for class: '" + bo.getClass().getName() + "'");

         }

                 // get the list of the foreign-keys for this reference-descriptor

         List fkFields = objectDescriptor.getForeignKeyFields();

         Iterator fkIterator = fkFields.iterator();

         // walk through the list of the foreign keys, get their types

         while (fkIterator.hasNext()) {

             // get the field name of the fk & pk field

             String fkFieldName = (String) fkIterator.next();

             // get the value for the fk field

             Object fkFieldValue = null;

             try {

                 fkFieldValue = PropertyUtils.getSimpleProperty(bo, fkFieldName);

             }

             // if we cant retrieve the field value, then

             // it doesnt have a value

             catch (IllegalAccessException e) {

                 return false;

                         } catch (InvocationTargetException e) {

                 return false;

                         } catch (NoSuchMethodException e) {

                 return false;

             }

             // test the value

             if (fkFieldValue == null) {

                 return false;

                         } else if (String.class.isAssignableFrom(fkFieldValue.getClass())) {

                 if (StringUtils.isBlank((String) fkFieldValue)) {

                     return false;

                 }

             }

         }

         return allFkeysHaveValues;

     }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#clearCache()

          */

         public void clearCache() {

                 persistenceDao.clearCache();

         }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#getFlattenedPrimaryKeyFieldValues(java.lang.Object)

          */

         public String getFlattenedPrimaryKeyFieldValues(Object persistableObject) {

         if (persistableObject == null) {

             throw new IllegalArgumentException("invalid (null) persistableObject");

         }

         Map primaryKeyValues = getPrimaryKeyFieldValues(persistableObject, true);

         StringBuffer flattened = new StringBuffer(persistableObject.getClass().getName());

         flattened.append("(");

         for (Iterator i = primaryKeyValues.entrySet().iterator(); i.hasNext();) {

             Map.Entry e = (Map.Entry) i.next();

             String fieldName = (String) e.getKey();

             Object fieldValue = e.getValue();

             flattened.append(fieldName + "=" + fieldValue);

             if (i.hasNext()) {

                 flattened.append(",");

             }

         }

         flattened.append(")");

         return flattened.toString();

         }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#linkObjects(java.lang.Object)

          */

         public void linkObjects(Object persistableObject) {

                 linkObjectsWithCircularReferenceCheck(persistableObject, new HashSet());

         }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#loadRepositoryDescriptor(java.lang.String)

          */

         public void loadRepositoryDescriptor(String ojbRepositoryFilePath) {}

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#refreshAllNonUpdatingReferences(org.kuali.rice.krad.bo.PersistableBusinessObject)

          */

         public void refreshAllNonUpdatingReferences(PersistableBusinessObject bo) {

                 EntityDescriptor descriptor = MetadataManager.getEntityDescriptor(bo.getClass());

                 List<ObjectDescriptor> objectDescriptors = descriptor.getObjectRelationships();

                 for (ObjectDescriptor od : objectDescriptors) {

             if (od.getCascade().length == 0) {                   

                 retrieveReferenceObject(bo, od.getAttributeName());

             }                        

                 }

     }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#resolveProxy(java.lang.Object)

          */

         public Object resolveProxy(Object o) {

                 return persistenceDao.resolveProxy(o);

         }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#retrieveNonKeyFields(java.lang.Object)

          */

         public void retrieveNonKeyFields(Object persistableObject) {

         if (persistableObject == null) {

             throw new IllegalArgumentException("invalid (null) persistableObject");

         }

         LOG.debug("retrieving non-key fields for " + persistableObject);

         persistenceDao.retrieveAllReferences(persistableObject);

     }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#retrieveReferenceObject(java.lang.Object, java.lang.String)

          */

         public void retrieveReferenceObject(Object persistableObject, String referenceObjectName) {

         if (persistableObject == null) {

             throw new IllegalArgumentException("invalid (null) persistableObject");

         }

         LOG.debug("retrieving reference object " + referenceObjectName + " for " + persistableObject);

         persistenceDao.retrieveReference(persistableObject, referenceObjectName);

     }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#retrieveReferenceObjects(java.lang.Object, java.util.List)

          */

         public void retrieveReferenceObjects(Object persistableObject, List referenceObjectNames) {

         if (persistableObject == null) {

             throw new IllegalArgumentException("invalid (null) persistableObject");

         }

         if (referenceObjectNames == null) {

             throw new IllegalArgumentException("invalid (null) referenceObjectNames");

         }

         if (referenceObjectNames.isEmpty()) {

             throw new IllegalArgumentException("invalid (empty) referenceObjectNames");

         }

         int index = 0;

         for (Iterator i = referenceObjectNames.iterator(); i.hasNext(); index++) {

             String referenceObjectName = (String) i.next();

             if (StringUtils.isBlank(referenceObjectName)) {

                 throw new IllegalArgumentException("invalid (blank) name at position " + index);

             }

             retrieveReferenceObject(persistableObject, referenceObjectName);

         }

         }

         /**

          * @see org.kuali.rice.krad.service.PersistenceService#retrieveReferenceObjects(java.util.List, java.util.List)

          */

         public void retrieveReferenceObjects(List persistableObjects, List referenceObjectNames) {

         if (persistableObjects == null) {

             throw new IllegalArgumentException("invalid (null) persistableObjects");

         }

         if (persistableObjects.isEmpty()) {

             throw new IllegalArgumentException("invalid (empty) persistableObjects");

         }

         if (referenceObjectNames == null) {

             throw new IllegalArgumentException("invalid (null) referenceObjectNames");

         }

         if (referenceObjectNames.isEmpty()) {

             throw new IllegalArgumentException("invalid (empty) referenceObjectNames");

         }

         for (Iterator i = persistableObjects.iterator(); i.hasNext();) {

             Object persistableObject = i.next();

             retrieveReferenceObjects(persistableObject, referenceObjectNames);

         }

         }

     private void linkObjectsWithCircularReferenceCheck(Object persistableObject, Set referenceSet) {

         if (ObjectUtils.isNull(persistableObject) || referenceSet.contains(persistableObject)) {

             return;

         }

         referenceSet.add(persistableObject);

         EntityDescriptor descriptor = MetadataManager.getEntityDescriptor(persistableObject.getClass());

         String className = null;

         String fieldName = null;

         try {

             // iterate through all object references for the persistableObject

                 List<ObjectDescriptor> objectDescriptors = descriptor.getObjectRelationships();

                 for (ObjectDescriptor od : objectDescriptors) {

                 // get the actual reference object

                 className = persistableObject.getClass().getName();

                 fieldName = od.getAttributeName();

                 Object referenceObject = PropertyUtils.getProperty(persistableObject, fieldName);

                 if (ObjectUtils.isNull(referenceObject) || referenceSet.contains(referenceObject)) {

                     continue;

                 }

                 // recursively link object

                 linkObjectsWithCircularReferenceCheck(referenceObject, referenceSet);

                                 // iterate through the keys for the reference object and set value

                 List<String> refFkNames = od.getForeignKeyFields();

                 EntityDescriptor refCld = MetadataManager.getEntityDescriptor(od.getTargetEntity());

                 Set<org.kuali.rice.core.framework.persistence.jpa.metadata.FieldDescriptor> refPkNames = refCld.getPrimaryKeys();

                 try {

                         for (String fk : refFkNames) {

                                                 Field f = referenceObject.getClass().getDeclaredField(fk);

                                                 f.setAccessible(true);

                                 if (ObjectUtils.isNull(f.get(referenceObject))) {

                                                         Field f2 = persistableObject.getClass().getDeclaredField(fk);

                                                         f2.setAccessible(true);

                                                         f.set(referenceObject, f2.get(persistableObject));

                                                 }                                

                                         }

                 } catch (Exception e) {

                         LOG.error(e.getMessage(), e);

                 }

             }

                 } catch (NoSuchMethodException e) {

             throw new IntrospectionException("no setter for property '" + className + "." + fieldName + "'", e);

                 } catch (IllegalAccessException e) {

             throw new IntrospectionException("problem accessing property '" + className + "." + fieldName + "'", e);

                 } catch (InvocationTargetException e) {

             throw new IntrospectionException("problem invoking getter for property '" + className + "." + fieldName + "'", e);

         }

     }

     /**

          * Asks persistenceDao if this represents a proxy

          * 

          * @see org.kuali.rice.krad.service.PersistenceService#isProxied(java.lang.Object)

          */

         public boolean isProxied(Object object) {

                 return persistenceDao.isProxied(object);

         }

 }