/*
 * 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.tuscany.sca.binding.sca.provider;

import org.apache.tuscany.sca.databinding.Mediator;
import org.apache.tuscany.sca.interfacedef.Operation;
import org.apache.tuscany.sca.invocation.Interceptor;
import org.apache.tuscany.sca.invocation.InvocationChain;
import org.apache.tuscany.sca.invocation.Invoker;
import org.apache.tuscany.sca.invocation.Message;
import org.apache.tuscany.sca.invocation.Phase;

/**
 * @version $Rev$ $Date$
 */
public class SCABindingInvoker implements Interceptor {
    private InvocationChain chain;
    private Mediator mediator;
    private Operation sourceOperation;
    private Operation targetOperation;
    private boolean passByValue;

    /**
     * Construct a SCABindingInvoker that delegates to the service invocaiton chain
     */
    public SCABindingInvoker(InvocationChain chain, Operation sourceOperation, Mediator mediator, boolean passByValue) {
        super();
        this.chain = chain;
        this.mediator = mediator;
        this.sourceOperation = sourceOperation;
        this.targetOperation = chain.getTargetOperation();
        this.passByValue = passByValue;
    }

    /**
     * @see org.apache.tuscany.sca.invocation.Interceptor#getNext()
     */
    public Invoker getNext() {
        return chain.getHeadInvoker(Phase.SERVICE_POLICY);
    }

    /**
     * @see org.apache.tuscany.sca.invocation.Interceptor#setNext(org.apache.tuscany.sca.invocation.Invoker)
     */
    public void setNext(Invoker next) {
        // NOOP
    }

    /**
     * @see org.apache.tuscany.sca.invocation.Invoker#invoke(org.apache.tuscany.sca.invocation.Message)
     */
    public Message invoke(Message msg) {

        if (passByValue) {
            msg.setBody(mediator.copyInput(msg.getBody(), sourceOperation, targetOperation));
        }

        Message resultMsg = getNext().invoke(msg);

        if (passByValue) {
            // Note source and target operation swapped so result is in source class loader
            if (resultMsg.isFault()) {
                resultMsg.setFaultBody(mediator.copyFault(resultMsg.getBody(), sourceOperation, targetOperation));
            } else {
                if (sourceOperation.getOutputType() != null) {
                    resultMsg.setBody(mediator.copyOutput(resultMsg.getBody(), sourceOperation, targetOperation));
                }
            }
        }

        return resultMsg;
    }

}