/*
 * Copyright (C) 2003 Erik Swenson - eswenson@opensourcesoft.net
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 * 
 * 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 General Public License for
 * more details.
 * 
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place - Suite 330, Boston, MA 02111-1307, USA.
 *  
 */

package org.efs.openreports.providers.persistence;

import java.io.Serializable;
import java.util.List;

import com.opensymphony.xwork.ActionContext;
import com.opensymphony.xwork.interceptor.component.ComponentManager;

import net.sf.hibernate.*;

import org.efs.openreports.providers.ProviderException;

public class HibernateProvider implements SessionFactoryProviderAware
{
	private SessionFactoryProvider sessionFactoryProvider;

	public HibernateProvider() throws ProviderException
	{
		try
		{
			ComponentManager container =
				(ComponentManager) ActionContext.getContext().get(
					"com.opensymphony.xwork.interceptor.component.ComponentManager");
			
			container.initializeObject(this);
		}
		catch (Exception e)
		{
			throw new ProviderException("Unable to create HibernateProvider");
		}
	}
	
	public Session openSession() throws ProviderException
	{
		try
		{
			return sessionFactoryProvider.getSessionFactory().openSession();
		}
		catch (HibernateException he)
		{
			throw new ProviderException(he);
		}
	}	

	public void closeSession(Session session) throws ProviderException
	{
		try
		{
			if (session != null)
				session.close();
		}
		catch (HibernateException he)
		{
			throw new ProviderException(he);
		}
	}

	public void rollbackTransaction(Transaction tx)
		throws ProviderException
	{
		try
		{
			if (tx != null)
				tx.rollback();
		}
		catch (HibernateException he)
		{
			throw new ProviderException(he);
		}
	}

	public Object save(Object object) throws ProviderException
	{
		Session session = openSession();
		Transaction tx = null;

		try
		{
			tx = session.beginTransaction();
			session.save(object);
			tx.commit();
		}
		catch (HibernateException he)
		{
			rollbackTransaction(tx);
			throw new ProviderException(he);
		}
		finally
		{
			closeSession(session);
		}

		return object;
	}

	public void update(Object object) throws ProviderException
	{
		Session session = openSession();
		Transaction tx = null;

		try
		{
			tx = session.beginTransaction();
			session.update(object);
			tx.commit();
		}
		catch (HibernateException he)
		{
			rollbackTransaction(tx);
			throw new ProviderException(he);
		}
		finally
		{
			closeSession(session);
		}
	}

	public void delete(Object object)
		throws ProviderException, ConstraintException
	{
		Session session = openSession();
		Transaction tx = null;

		try
		{
			tx = session.beginTransaction();
			session.delete(object);
			tx.commit();
		}
		catch (HibernateException he)
		{
			rollbackTransaction(tx);
			
			if (he.getCause().getMessage().toUpperCase().indexOf("CONSTRAINT") > 0)
			{
				throw new ConstraintException(he.getMessage());
			}

			throw new ProviderException(he);
		}
		finally
		{
			closeSession(session);
		}
	}

	public Object load(Class classType, Serializable id)
		throws ProviderException
	{
		Session session = openSession();
		Transaction tx = null;

		try
		{
			tx = session.beginTransaction();
			Object object = session.load(classType, id);
			tx.commit();

			return object;
		}
		catch (HibernateException he)
		{
			rollbackTransaction(tx);
			throw new ProviderException(he);
		}
		finally
		{
			closeSession(session);
		}
	}

	public List query(String fromClause) throws ProviderException
	{
		Session session = openSession();
		Transaction tx = null;

		try
		{
			tx = session.beginTransaction();

			Query query = session.createQuery(fromClause);
			List list = query.list();

			tx.commit();

			return list;
		}
		catch (HibernateException he)
		{
			rollbackTransaction(tx);
			throw new ProviderException(he);
		}
		finally
		{
			closeSession(session);
		}
	}

	public void setSessionFactoryProvider(SessionFactoryProvider sessionFactoryProvider)
	{
		this.sessionFactoryProvider = sessionFactoryProvider;
	}

}