/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Middleware LLC.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 *
 */
package org.hibernate.event.def;

import java.io.Serializable;

import org.hibernate.HibernateException;
import org.hibernate.ObjectDeletedException;
import org.hibernate.EntityMode;
import org.hibernate.engine.EntityEntry;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.engine.Status;
import org.hibernate.event.SaveOrUpdateEvent;
import org.hibernate.persister.entity.EntityPersister;

/**
 * An event handler for update() events
 * @author Gavin King
 */
public class DefaultUpdateEventListener extends DefaultSaveOrUpdateEventListener {

	protected Serializable performSaveOrUpdate(SaveOrUpdateEvent event) {
		// this implementation is supposed to tolerate incorrect unsaved-value
		// mappings, for the purpose of backward-compatibility
		EntityEntry entry = event.getSession().getPersistenceContext().getEntry( event.getEntity() );
		if ( entry!=null ) {
			if ( entry.getStatus()==Status.DELETED ) {
				throw new ObjectDeletedException( "deleted instance passed to update()", null, event.getEntityName() );
			}
			else {
				return entityIsPersistent(event);
			}
		}
		else {
			entityIsDetached(event);
			return null;
		}
	}
	
	/**
	 * If the user specified an id, assign it to the instance and use that, 
	 * otherwise use the id already assigned to the instance
	 */
	protected Serializable getUpdateId(
			Object entity,
			EntityPersister persister,
			Serializable requestedId,
			SessionImplementor session) throws HibernateException {
		if ( requestedId == null ) {
			return super.getUpdateId( entity, persister, requestedId, session );
		}
		else {
			persister.setIdentifier( entity, requestedId, session );
			return requestedId;
		}
	}

}
