/*
 * 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.core.invocation;

import java.lang.reflect.Method;
import java.util.List;

import org.apache.tuscany.sca.runtime.RuntimeWire;
import org.apache.tuscany.sca.runtime.EndpointReference;
import org.apache.tuscany.sca.interfacedef.InterfaceContract;
import org.apache.tuscany.sca.interfacedef.Interface;
import org.apache.tuscany.sca.interfacedef.Operation;
import org.apache.tuscany.sca.assembly.Service;
import org.apache.tuscany.sca.assembly.Consumer;

/**
 * Class which provides methods which assist in the invocation of Consumer methods
 * @author MikeEdwards
 *
 */
public class ConsumerInvokerHelper {
	
	/**
	 * Returns the name of the Consumer operation for a given event type
	 * @param Args - the parameters for the method to invoke
	 * @param wire - the runtime wire involved in the invocation
	 * @return - the name of the operation - null if no corresponding operation can be found
	 */
	public static String returnConsumerOperation( Object[] Args, RuntimeWire wire ) {
		if( isTargetConsumer( wire ) ) {
			Consumer consumer = getTargetConsumer( wire );
			String eventType = getEventType( Args[0] );
			if( consumer != null ) {
				return consumer.getOperationByEventType(eventType);
			} // end if
		} // end if
		return null;
	} // end returnConsumerMethod
	
	/**
	 * Find the event type associated with the argument
	 * @param arg - the argument
	 * @return a String containing the event type
	 */
	static String getEventType( Object arg ) {
		Class<?> clazz = arg.getClass();
		String name = clazz.getCanonicalName();

		// Deal with the case where the argument is some XML holder class (need to look for top level child
		// object with some "real class"
		
		// Check if the class is marked with an EventType
		org.osoa.sca.annotations.EventType eventType = clazz.getAnnotation(org.osoa.sca.annotations.EventType.class);
        if (eventType != null) {
            return eventType.name();
        } else { 
        	return name;
        }// end if 
	} // end getEventType
	
	/**
	 * For a wire target that is a consumer, returns the Consumer object
	 * @param wire - the wire
	 * @return a Consumer if the wire targets a consumer - otherwise null
	 */
	static Consumer getTargetConsumer( RuntimeWire wire ) {
		return ((Service)wire.getTarget().getContract()).getConsumer();
	}
	
	
	/**
	 * Determines whether the target of a wire is a Consumer
	 * @param wire - a runtime wire
	 * @return - true if the target of the wire is a Consumer, false otherwise
	 */
	static boolean isTargetConsumer( RuntimeWire wire ) {
		Service service = (Service)wire.getTarget().getContract();
		return service.isConsumer();
	} // end isTargetConsumer

} // end class ConsumerInvokerHelper