/**
 * Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership. Apereo
 * 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 the
 * following location:
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0
 *
 * <p>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.apereo.portal.spring.tx;

import com.google.common.collect.MapMaker;
import java.util.Map;
import java.util.Properties;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.interceptor.TransactionAttribute;
import org.springframework.transaction.interceptor.TransactionAttributeSource;
import org.springframework.transaction.interceptor.TransactionInterceptor;
import org.springframework.util.StringUtils;

/**
 * Caches lookups for TX managers specified by qualifier in a local map
 *
 */
public class TransactionManagerCachingTransactionInterceptor extends TransactionInterceptor {
    private static final long serialVersionUID = 1L;

    private final Map<String, PlatformTransactionManager> platformTransactionManagerCache =
            new MapMaker().weakValues().makeMap();

    public TransactionManagerCachingTransactionInterceptor() {
        super();
    }

    public TransactionManagerCachingTransactionInterceptor(
            PlatformTransactionManager ptm, Properties attributes) {
        super(ptm, attributes);
    }

    public TransactionManagerCachingTransactionInterceptor(
            PlatformTransactionManager ptm, TransactionAttributeSource tas) {
        super(ptm, tas);
    }

    protected PlatformTransactionManager determineTransactionManager(TransactionAttribute txAttr) {
        if (txAttr == null) {
            return super.determineTransactionManager(txAttr);
        }

        final String qualifier = txAttr.getQualifier();
        if (StringUtils.hasLength(qualifier)) {
            PlatformTransactionManager platformTransactionManager =
                    platformTransactionManagerCache.get(qualifier);
            if (platformTransactionManager == null) {
                platformTransactionManager = super.determineTransactionManager(txAttr);
                platformTransactionManagerCache.put(qualifier, platformTransactionManager);
            }

            return platformTransactionManager;
        }

        return super.determineTransactionManager(txAttr);
    }
}