/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache 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.apache.org/licenses/LICENSE-2.0
 *
 * 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.apache.activemq.pool;

import javax.jms.JMSException;
import javax.jms.Session;
import javax.transaction.RollbackException;
import javax.transaction.Status;
import javax.transaction.SystemException;
import javax.transaction.TransactionManager;
import javax.transaction.xa.XAResource;

import org.apache.activemq.ActiveMQConnection;
import org.apache.commons.pool.ObjectPoolFactory;

/**
 * An XA-aware connection pool.  When a session is created and an xa transaction is active,
 * the session will automatically be enlisted in the current transaction.
 * 
 * @author gnodet
 */
public class XaConnectionPool extends ConnectionPool {

    private TransactionManager transactionManager;

    public XaConnectionPool(ActiveMQConnection connection, ObjectPoolFactory poolFactory, TransactionManager transactionManager) {
        super(connection, poolFactory);
        this.transactionManager = transactionManager;
    }

    public Session createSession(boolean transacted, int ackMode) throws JMSException {
        try {
            boolean isXa = (transactionManager != null && transactionManager.getStatus() != Status.STATUS_NO_TRANSACTION);
            if (isXa) {
                transacted = true;
                ackMode = Session.SESSION_TRANSACTED;
            }
            PooledSession session = (PooledSession) super.createSession(transacted, ackMode);
            if (isXa) {
                session.setIgnoreClose(true);
                transactionManager.getTransaction().registerSynchronization(new Synchronization(session));
                incrementReferenceCount();
                transactionManager.getTransaction().enlistResource(createXaResource(session));
            }
            return session;
        } catch (RollbackException e) {
            final JMSException jmsException = new JMSException("Rollback Exception");
            jmsException.initCause(e);
            throw jmsException;
        } catch (SystemException e) {
            final JMSException jmsException = new JMSException("System Exception");
            jmsException.initCause(e);
            throw jmsException;
        }
    }

    protected XAResource createXaResource(PooledSession session) throws JMSException {
        return session.getXAResource();
    }
    
    
    protected class Synchronization implements javax.transaction.Synchronization {
        private final PooledSession session;

        private Synchronization(PooledSession session) {
            this.session = session;
        }

        public void beforeCompletion() {
        }
        
        public void afterCompletion(int status) {
            try {
                // This will return session to the pool.
                session.setIgnoreClose(false);
                session.close();
                decrementReferenceCount();
            } catch (JMSException e) {
                throw new RuntimeException(e);
            }
        }
    }
    
}
