/*

  * Copyright 2006-2011 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 org.apache.commons.beanutils.PropertyUtils;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.core.api.config.property.ConfigContext;

 import org.kuali.rice.kim.api.services.KimApiServiceLocator;

 import org.kuali.rice.kim.bo.Person;

 import org.kuali.rice.kim.service.PersonService;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

 import org.springframework.transaction.annotation.Transactional;

 import java.beans.PropertyDescriptor;

 import java.util.Collection;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.List;

 import java.util.Map;

 import java.util.Set;

 /**

  * This class is the service implementation for the BusinessObjectService structure. This is the default implementation, that is

  * delivered with Kuali.

  */

 public class BusinessObjectServiceImpl implements BusinessObjectService {

     private PersistenceService persistenceService;

     private PersistenceStructureService persistenceStructureService;

     private BusinessObjectDao businessObjectDao;

     private PersonService personService;

     private BusinessObjectMetaDataService businessObjectMetaDataService;

     private boolean illegalBusinessObjectsForSaveInitialized;

     private final Set<String> illegalBusinessObjectsForSave = new HashSet<String>();

     @Override

     @Transactional

     public <T extends PersistableBusinessObject> T save(T bo) {

             validateBusinessObjectForSave(bo);

         return (T) businessObjectDao.save(bo);

     }

     @Override

     @Transactional

     public List<? extends PersistableBusinessObject> save(List<? extends PersistableBusinessObject> businessObjects) {

         validateBusinessObjectForSave(businessObjects);

         return businessObjectDao.save(businessObjects);

     }

     @Override

     @Transactional

     public PersistableBusinessObject linkAndSave(PersistableBusinessObject bo) {

             validateBusinessObjectForSave(bo);

         persistenceService.linkObjects(bo);

         return businessObjectDao.save(bo);

     }

     @Override

     @Transactional

     public List<? extends PersistableBusinessObject> linkAndSave(List<? extends PersistableBusinessObject> businessObjects) {

         validateBusinessObjectForSave(businessObjects);

         return businessObjectDao.save(businessObjects);

     }

     protected void validateBusinessObjectForSave(PersistableBusinessObject bo) {

             if (bo == null) {

             throw new IllegalArgumentException("Object passed in is null");

         }

         if (!isBusinessObjectAllowedForSave(bo)) {

                 throw new IllegalArgumentException("Object passed in is a BusinessObject but has been restricted from save operations according to configuration parameter '" + KRADConstants.Config.ILLEGAL_BUSINESS_OBJECTS_FOR_SAVE);

         }

     }

     protected void validateBusinessObjectForSave(List<? extends PersistableBusinessObject> businessObjects) {

             for (PersistableBusinessObject bo : businessObjects) {

                      if (bo == null) {

                  throw new IllegalArgumentException("One of the objects in the List is null.");

              }

                      if (!isBusinessObjectAllowedForSave(bo)) {

                              throw new IllegalArgumentException("One of the objects in the List is a BusinessObject but has been restricted from save operations according to configuration parameter '" + KRADConstants.Config.ILLEGAL_BUSINESS_OBJECTS_FOR_SAVE

                                              + "  Passed in type was '" + bo.getClass().getName() + "'.");

                      }

             }

     }

     /**

      * Returns true if the BusinessObjectService should be permitted to save instances of the given PersistableBusinessObject.

      * Implementation checks a configuration parameter for class names of PersistableBusinessObjects that shouldn't be allowed

      * to be saved.

      */

     protected boolean isBusinessObjectAllowedForSave(PersistableBusinessObject bo) {

             if (!illegalBusinessObjectsForSaveInitialized) {

                     synchronized (this) {

                             boolean applyCheck = true;

                             String applyCheckValue = ConfigContext.getCurrentContextConfig().getProperty(KRADConstants.Config.APPLY_ILLEGAL_BUSINESS_OBJECT_FOR_SAVE_CHECK);

                             if (!StringUtils.isEmpty(applyCheckValue)) {

                                     applyCheck = Boolean.valueOf(applyCheckValue);

                             }

                             if (applyCheck) {

                                     String illegalBos = ConfigContext.getCurrentContextConfig().getProperty(KRADConstants.Config.ILLEGAL_BUSINESS_OBJECTS_FOR_SAVE);

                                     if (!StringUtils.isEmpty(illegalBos)) {

                                             String[] illegalBosSplit = illegalBos.split(",");

                                             for (String illegalBo : illegalBosSplit) {

                                                     illegalBusinessObjectsForSave.add(illegalBo.trim());

                                             }

                                     }

                             }

                     }

                     illegalBusinessObjectsForSaveInitialized = true;

             }

             return !illegalBusinessObjectsForSave.contains(bo.getClass().getName());

     }

     @Override

         public <T extends BusinessObject> T findBySinglePrimaryKey(Class<T> clazz, Object primaryKey) {

                 return businessObjectDao.findBySinglePrimaryKey(clazz, primaryKey);

         }

     @Override

     public <T extends BusinessObject> T findByPrimaryKey(Class<T> clazz, Map<String, ?> primaryKeys) {

         return businessObjectDao.findByPrimaryKey(clazz, primaryKeys);

     }

     @Override

     public PersistableBusinessObject retrieve(PersistableBusinessObject object) {

         return businessObjectDao.retrieve(object);

     }

     @Override

     public <T extends BusinessObject> Collection<T> findAll(Class<T> clazz) {

         return businessObjectDao.findAll(clazz);

     }

     @Override

     public <T extends BusinessObject> Collection<T> findAllOrderBy( Class<T> clazz, String sortField, boolean sortAscending ) {

             final Map<String, ?> emptyParameters = Collections.emptyMap();

             return businessObjectDao.findMatchingOrderBy(clazz, emptyParameters, sortField, sortAscending );

     }

     @Override

     public <T extends BusinessObject> Collection<T> findMatching(Class<T> clazz, Map<String, ?> fieldValues) {

         return businessObjectDao.findMatching(clazz, fieldValues);

     }

     @Override

     public int countMatching(Class clazz, Map<String, ?> fieldValues) {

         return businessObjectDao.countMatching(clazz, fieldValues);

     }

     @Override

     public int countMatching(Class clazz, Map<String, ?> positiveFieldValues, Map<String, ?> negativeFieldValues) {

         return businessObjectDao.countMatching(clazz, positiveFieldValues, negativeFieldValues);

     }

     @Override

     public <T extends BusinessObject> Collection<T> findMatchingOrderBy(Class<T> clazz, Map<String, ?> fieldValues, String sortField, boolean sortAscending) {

         return businessObjectDao.findMatchingOrderBy(clazz, fieldValues, sortField, sortAscending);

     }

     @Override

     @Transactional

     public void delete(PersistableBusinessObject bo) {

         businessObjectDao.delete(bo);

     }

     @Override

     @Transactional

     public void delete(List<? extends PersistableBusinessObject> boList) {

         businessObjectDao.delete(boList);

     }

     @Override

     @Transactional

     public void deleteMatching(Class clazz, Map<String, ?> fieldValues) {

         businessObjectDao.deleteMatching(clazz, fieldValues);

     }

     @Override

     public BusinessObject getReferenceIfExists(BusinessObject bo, String referenceName) {

         // if either argument is null, then we have nothing to do, complain and abort

         if (ObjectUtils.isNull(bo)) {

             throw new IllegalArgumentException("Passed in BusinessObject was null.  No processing can be done.");

         }

         if (StringUtils.isEmpty(referenceName)) {

             throw new IllegalArgumentException("Passed in referenceName was empty or null.  No processing can be done.");

         }

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

         PropertyDescriptor propertyDescriptor;

         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() + "'. GFK");

         }

         // get the class of the attribute name

         Class referenceClass = ObjectUtils.getPropertyType( bo, referenceName, persistenceStructureService );

         if ( referenceClass == null ) {

                 referenceClass = propertyDescriptor.getPropertyType();

         }

         /*

          * check for Person or EBO references in which case we can just get the reference through propertyutils

          */

         if (ExternalizableBusinessObject.class.isAssignableFrom(referenceClass)) {

             try {

                     BusinessObject referenceBoExternalizable = (BusinessObject) PropertyUtils.getProperty(bo, referenceName);

                     if (referenceBoExternalizable!=null) {

                             return referenceBoExternalizable;

                 }

             } catch (Exception ex) {

                 //throw new RuntimeException("Unable to get property " + referenceName + " from a BO of class: " + bo.getClass().getName(),ex);

                     //Proceed further - get the BO relationship using responsible module service and proceed further

             }

         }

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

         // otherwise throw an exception

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

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

         }

         // get the list of foreign-keys for this reference. if the reference

         // does not exist, or is not a reference-descriptor, an exception will

         // be thrown here.

         BusinessObjectRelationship boRel = businessObjectMetaDataService.getBusinessObjectRelationship( bo, referenceName );

         final Map<String,String> fkMap = boRel != null ? boRel.getParentToChildReferences() : Collections.<String, String>emptyMap();

         boolean allFkeysHaveValues = true;

         // walk through the foreign keys, testing each one to see if it has a value

         Map<String,Object> pkMap = new HashMap<String,Object>();

         for (Map.Entry<String, String> entry : fkMap.entrySet()) {

             String fkFieldName = entry.getKey();

             String pkFieldName = entry.getValue();

             // attempt to retrieve the value for the given field

             Object fkFieldValue;

             try {

                 fkFieldValue = PropertyUtils.getProperty(bo, fkFieldName);

             }

             catch (Exception e) {

                 throw new RuntimeException(e);

             }

             // determine if there is a value for the field

             if (ObjectUtils.isNull(fkFieldValue)) {

                 allFkeysHaveValues = false;

                 break; // no reason to continue processing the fkeys

             }

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

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

                     allFkeysHaveValues = false;

                     break;

                 }

                 else {

                     pkMap.put(pkFieldName, fkFieldValue);

                 }

             }

             // if there is a value, grab it

             else {

                 pkMap.put(pkFieldName, fkFieldValue);

             }

         }

         BusinessObject referenceBo = null;

         // only do the retrieval if all Foreign Keys have values

         if (allFkeysHaveValues) {

                 if (ExternalizableBusinessObject.class.isAssignableFrom(referenceClass)) {

                         ModuleService responsibleModuleService = KRADServiceLocatorWeb.getKualiModuleService().getResponsibleModuleService(referenceClass);

                                 if(responsibleModuleService!=null) {

                                         return responsibleModuleService.<ExternalizableBusinessObject>getExternalizableBusinessObject(referenceClass, pkMap);

                                 }

                 } else

                         referenceBo = this.<BusinessObject>findByPrimaryKey(referenceClass, pkMap);

         }

         // return what we have, it'll be null if it was never retrieved

         return referenceBo;

     }

     @Override

     public void linkUserFields(PersistableBusinessObject bo) {

         if (bo == null) {

             throw new IllegalArgumentException("bo passed in was null");

         }

         bo.linkEditableUserFields();

         linkUserFields( Collections.singletonList( bo ) );

     }

     @Override

     public void linkUserFields(List<PersistableBusinessObject> bos) {

         // do nothing if there's nothing to process

         if (bos == null) {

             throw new IllegalArgumentException("List of bos passed in was null");

         }

         else if (bos.isEmpty()) {

             return;

         }

         Person person;

         for (PersistableBusinessObject bo : bos) {

             // get a list of the reference objects on the BO

             List<BusinessObjectRelationship> relationships = businessObjectMetaDataService.getBusinessObjectRelationships( bo );

             for ( BusinessObjectRelationship rel : relationships ) {

                 if ( Person.class.isAssignableFrom( rel.getRelatedClass() ) ) {

                     person = (Person) ObjectUtils.getPropertyValue(bo, rel.getParentAttributeName() );

                     if (person != null) {

                         // find the universal user ID relationship and link the field

                         for ( Map.Entry<String,String> entry : rel.getParentToChildReferences().entrySet() ) {

                             if ( "principalId".equals(entry.getValue())) {

                                 linkUserReference(bo, person, rel.getParentAttributeName(), entry.getKey() );

                                 break;

                             }

                         }

                     }                    

                 }

             }

             if ( persistenceStructureService.isPersistable(bo.getClass())) {

                     Map<String, Class> references = persistenceStructureService.listReferenceObjectFields(bo);

                     // walk through the ref objects, only doing work if they are Person objects

                     for ( Map.Entry<String, Class> entry : references.entrySet() ) {

                         if (Person.class.isAssignableFrom(entry.getValue())) {

                             person = (Person) ObjectUtils.getPropertyValue(bo, entry.getKey());

                             if (person != null) {

                                 String fkFieldName = persistenceStructureService.getForeignKeyFieldName(bo.getClass(), entry.getKey(), "principalId");

                                 linkUserReference(bo, person, entry.getKey(), fkFieldName);

                             }

                         }

                     }

             }

         }

     }

     /**

      * 

      * This method links a single UniveralUser back to the parent BO based on the authoritative principalName.

      * 

      * @param bo

      * @param refFieldName

      */

     private void linkUserReference(PersistableBusinessObject bo, Person user, String refFieldName, String fkFieldName) {

         // if the UserId field is blank, there's nothing we can do, so quit

         if (StringUtils.isBlank(user.getPrincipalName())) {

             return;

         }

         // attempt to load the user from the user-name, exit quietly if the user isnt found

         Person userFromService = getPersonService().getPersonByPrincipalName(user.getPrincipalName());

         if (userFromService == null) {

             return;

         }

         // attempt to set the universalId on the parent BO

         setBoField(bo, fkFieldName, userFromService.getPrincipalId());

     }

     private void setBoField(PersistableBusinessObject bo, String fieldName, Object fieldValue) {

         try {

             ObjectUtils.setObjectProperty(bo, fieldName, fieldValue.getClass(), fieldValue);

         }

         catch (Exception e) {

             throw new RuntimeException("Could not set field [" + fieldName + "] on BO to value: " + fieldValue.toString() + " (see nested exception for details).", e);

         }

     }

     @Override

         public PersistableBusinessObject manageReadOnly(PersistableBusinessObject bo) {

                 return getBusinessObjectDao().manageReadOnly(bo);

         }

         /**

      * Gets the businessObjectDao attribute.

      * 

      * @return Returns the businessObjectDao.

      */

     protected BusinessObjectDao getBusinessObjectDao() {

         return businessObjectDao;

     }

     /**

      * Sets the businessObjectDao attribute value.

      * 

      * @param businessObjectDao The businessObjectDao to set.

      */

     public void setBusinessObjectDao(BusinessObjectDao businessObjectDao) {

         this.businessObjectDao = businessObjectDao;

     }

     /**

      * Sets the persistenceStructureService attribute value.

      * 

      * @param persistenceStructureService The persistenceStructureService to set.

      */

     public void setPersistenceStructureService(PersistenceStructureService persistenceStructureService) {

         this.persistenceStructureService = persistenceStructureService;

     }

     /**

      * Sets the kualiUserService attribute value.

      */

         public final void setPersonService(PersonService personService) {

         this.personService = personService;

     }

         protected PersonService getPersonService() {

         return personService != null ? personService : (personService = KimApiServiceLocator.getPersonService());

     }

     /**

      * Sets the persistenceService attribute value.

      * 

      * @param persistenceService The persistenceService to set.

      */

     public final void setPersistenceService(PersistenceService persistenceService) {

         this.persistenceService = persistenceService;

     }

     protected BusinessObjectMetaDataService getBusinessObjectMetaDataService() {

         return businessObjectMetaDataService;

     }

     public void setBusinessObjectMetaDataService(BusinessObjectMetaDataService boMetadataService) {

         this.businessObjectMetaDataService = boMetadataService;

     }

 }