/*
 * Copyright (c) 2010-2016. Axon Framework
 *
 * 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.axonframework.messaging.interceptors;

import org.axonframework.messaging.InterceptorChain;
import org.axonframework.messaging.Message;
import org.axonframework.messaging.MessageHandlerInterceptor;
import org.axonframework.messaging.correlation.CorrelationDataProvider;
import org.axonframework.messaging.unitofwork.UnitOfWork;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * Message interceptor that registers {@link CorrelationDataProvider CorrelationDataProviders} with the Unit of Work.
 * <p/>
 * The registered CorrelationDataProviders copy correlation MetaData over from the Message processed by the Unit of Work
 * to new Messages that are created during processing.
 *
 * @param <T> The type of Message that can be intercepted
 * @author Rene de Waele
 * @since 3.0
 */
public class CorrelationDataInterceptor<T extends Message<?>> implements MessageHandlerInterceptor<T> {

    private final List<CorrelationDataProvider> correlationDataProviders;

    /**
     * Initializes the interceptor that registers given {@code correlationDataProvider} with the current Unit of Work.
     *
     * @param correlationDataProviders The CorrelationDataProviders to register with the Interceptor
     */
    public CorrelationDataInterceptor(Collection<CorrelationDataProvider> correlationDataProviders) {
        this.correlationDataProviders = new ArrayList<>(correlationDataProviders);
    }

    @Override
    public Object handle(UnitOfWork<? extends T> unitOfWork, InterceptorChain interceptorChain) throws Exception {
        correlationDataProviders.forEach(unitOfWork::registerCorrelationDataProvider);
        return interceptorChain.proceed();
    }

}