package org.trails.component;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import org.apache.tapestry.IAsset;

 import org.apache.tapestry.annotations.Asset;

 import org.apache.tapestry.annotations.ComponentClass;

 import org.apache.tapestry.annotations.InjectObject;

 import org.apache.tapestry.annotations.Parameter;

 import org.apache.tapestry.form.IPropertySelectionModel;

 import org.hibernate.criterion.DetachedCriteria;

 import org.hibernate.criterion.Restrictions;

 import org.trails.descriptor.IClassDescriptor;

 import org.trails.persistence.HibernatePersistenceService;

 /**

  * This component produces a editor for a ManyToOne or ManyToMany collection

  */

 @ComponentClass(allowBody = true, allowInformalParameters = true)

 public abstract class HibernateEditCollection extends EditCollection

 {

         @Asset(value = "/org/trails/component/EditCollection.html")

         public abstract IAsset get$template();

         protected static final Log LOG = LogFactory.getLog(HibernateEditCollection.class);

         /**

          * @todo: remove when the components reuse issue goes away

          */

         @InjectObject("service:trails.hibernate.PersistenceService")

         public abstract HibernatePersistenceService getHibernatePersistenceService();

         /**

          * @todo: remove when the components reuse issue goes away

          */

         @Override

         public HibernatePersistenceService getPersistenceService()

         {

                 return getHibernatePersistenceService();

         }

         @Parameter(required = false)

         public abstract DetachedCriteria getCriteria();

         /**

          * @return

          */

         public IPropertySelectionModel getSelectionModel()

         {

                 IClassDescriptor elementDescriptor = getDescriptorService().getClassDescriptor(getCollectionDescriptor().getElementType());

                 if (getCriteria() == null)

                 {

                         // don't allow use to select from all here

                         if (getCollectionDescriptor().isChildRelationship())

                         {

                                 return new IdentifierSelectionModel(getSelectedList(), elementDescriptor.getIdentifierDescriptor().getName());

                         }

                         // but do here

                         else if (getCollectionDescriptor().getInverseProperty() != null && getCollectionDescriptor().isOneToMany())

                         {

                                 DetachedCriteria criteria = DetachedCriteria.forClass(getCollectionDescriptor().getElementType());

                                 String identifier = elementDescriptor.getIdentifierDescriptor().getName();

                                 if (getModel() != null)

                                 {

                                         criteria.add(

                                                         Restrictions.disjunction()

                                                                         .add(Restrictions.isNull(getCollectionDescriptor().getInverseProperty()))

                                                                         .add(Restrictions.eq(

                                                                         getCollectionDescriptor().getInverseProperty() + "." + identifier,

                                                                         getPersistenceService().getIdentifier(getModel(), elementDescriptor))));

                                 } else

                                 {

                                         criteria.add(Restrictions.isNull(getCollectionDescriptor().getInverseProperty()));

                                 }

                                 return new IdentifierSelectionModel(getPersistenceService().getInstances(getCollectionDescriptor().getElementType(), criteria), elementDescriptor.getIdentifierDescriptor().getName());

                         } else

                         {

                                 return new IdentifierSelectionModel(getPersistenceService().getAllInstances(getCollectionDescriptor().getElementType()),

                                         elementDescriptor.getIdentifierDescriptor().getName());

                         }

                 } else

                 {

                         return new IdentifierSelectionModel(

                                         getPersistenceService().getInstances(getCollectionDescriptor().getElementType(), getCriteria()),

                                         elementDescriptor.getIdentifierDescriptor().getName());

                 }

         }

 }