/*
 * Copyright 2002-2015 SCOOP Software GmbH
 *
 * Licensed 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.copperengine.spring;

import java.sql.Connection;

import javax.sql.DataSource;

import org.copperengine.core.persistent.txn.DatabaseTransaction;
import org.copperengine.core.persistent.txn.Transaction;
import org.copperengine.core.persistent.txn.TransactionController;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.DefaultTransactionDefinition;

/**
 * Implementation of the {@link TransactionController} interface that internally uses Springs Transaction Management
 *
 * @author austermann
 */
public class SpringTransactionController implements TransactionController {

    private static final Logger logger = LoggerFactory.getLogger(SpringTransactionController.class);

    private DataSource dataSource;
    private PlatformTransactionManager transactionManager;

    public void setTransactionManager(PlatformTransactionManager transactionManager) {
        this.transactionManager = transactionManager;
    }

    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }

    @SuppressWarnings("unchecked")
    @Override
    public <T> T run(final DatabaseTransaction<T> txn) throws Exception {
        final T[] t = (T[]) new Object[1];
        new SpringTransaction() {
            @Override
            protected void execute(Connection con) throws Exception {
                t[0] = txn.run(con);
            }
        }.run(transactionManager, dataSource, new DefaultTransactionDefinition());
        return t[0];
    }

    @Override
    public <T> T run(Transaction<T> txn) throws Exception {
        final TransactionStatus txnStatus = transactionManager.getTransaction(new DefaultTransactionDefinition());
        T t = null;
        try {
            t = txn.run();
        } catch (Exception e) {
            logger.error("execution failed - rolling back transaction", e);
            transactionManager.rollback(txnStatus);
            throw e;
        }
        transactionManager.commit(txnStatus);
        return t;
    }

}