/**
 * Copyright (c) 2002-2012 "Neo Technology,"
 * Network Engine for Objects in Lund AB [http://neotechnology.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package org.neo4j.kernel.ha;

import org.neo4j.graphdb.event.ErrorState;
import org.neo4j.graphdb.event.KernelEventHandler;
import org.neo4j.kernel.impl.transaction.TxManager;
import org.neo4j.kernel.impl.transaction.XaDataSourceManager;

public class TxManagerCheckKernelEventHandler implements KernelEventHandler
{

    private final XaDataSourceManager dataSourceManager;
    private final TxManager txManager;

    public TxManagerCheckKernelEventHandler( XaDataSourceManager dataSourceManager, TxManager txManager )
    {
        this.dataSourceManager = dataSourceManager;
        this.txManager = txManager;
    }

    @Override
    public void beforeShutdown()
    {
    }

    @Override
    public void kernelPanic( ErrorState error )
    {
        if ( error == ErrorState.TX_MANAGER_NOT_OK )
        {
            try
            {
                synchronized ( dataSourceManager )
                {
                    txManager.stop();
                    dataSourceManager.stop();
                    dataSourceManager.start();
                    txManager.start();
                    txManager.doRecovery();

                }
            }
            catch (Throwable t)
            {
                throw new RuntimeException( "error while handling kernel panic for TX_MANAGER_NOT_OK", t );
            }
        }
    }

    @Override
    public Object getResource()
    {
        return null;
    }

    @Override
    public ExecutionOrder orderComparedTo( KernelEventHandler other )
    {
        return ExecutionOrder.DOESNT_MATTER;
    }
}