/**
 * 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.camel.artix.ds;

import java.io.IOException;

import biz.c24.io.api.data.ComplexDataObject;
import biz.c24.io.api.data.Element;
import biz.c24.io.api.data.ValidationException;
import biz.c24.io.api.transform.Transform;
import org.apache.camel.Exchange;
import org.apache.camel.InvalidPayloadException;
import org.apache.camel.Message;
import org.apache.camel.Processor;
import org.apache.camel.util.ObjectHelper;

/**
 * Transforms an <a href="http://activemq.apache.org/camel/artix-data-services.html">Artix Data Services</a>
 * object into some output format
 *
 * @version $Revision: 3061 $
 */
public class ArtixDSTransform implements Processor {
    private Transform transform;
    
    public ArtixDSTransform(Transform transform) {
        this.transform = transform;
    }

    public static ArtixDSTransform transform(Class<?> transformType) {
        Transform transformer = (Transform) ObjectHelper.newInstance(transformType);
        return transform(transformer);
    }

    public static ArtixDSTransform transform(Transform transformer) {
        return new ArtixDSTransform(transformer);
    }   

    public void process(Exchange exchange) throws Exception {
        ComplexDataObject[][] objects = null;
        ComplexDataObject dataObject = null;
        try {
            dataObject = exchange.getIn().getMandatoryBody(ComplexDataObject.class);
        } catch (InvalidPayloadException e1) {
            try {
                objects = exchange.getIn().getMandatoryBody(ComplexDataObject[][].class);
            } catch (InvalidPayloadException e2) {
                objects = getInBodyAsArray(exchange, objects);
            }
        }
            
        if (objects == null) {
            if (dataObject == null) {
                dataObject = unmarshalDataObject(exchange);
            }
            objects = new ComplexDataObject[][]{{dataObject}};
        }
        Object result = transform(objects);

        Message out = exchange.getOut();
        out.setBody(result);
    }

    private ComplexDataObject[][] getInBodyAsArray(Exchange exchange, ComplexDataObject[][] objects) {
        try {
            ComplexDataObject[] array = exchange.getIn().getMandatoryBody(ComplexDataObject[].class);
            if (array != null) {
                objects = new ComplexDataObject[][]{array};
            }
        } catch (InvalidPayloadException e) {
            // Do nothing here
        }
        return objects;
    }

    // Properties
    //-------------------------------------------------------------------------
    public Transform getTransform() {
        return transform;
    }

    public void setTransform(Transform transform) {
        this.transform = transform;
    }

    // Implementation methods
    //-------------------------------------------------------------------------

    protected Object transform(ComplexDataObject[][] objects) throws ValidationException {
        Transform transformer = getTransform();
        ComplexDataObject[][] answer = transformer.transform(objects);
        return answer[0][0];
    }

    // Implementation methods
    //-------------------------------------------------------------------------
    protected ComplexDataObject unmarshalDataObject(Exchange exchange) throws InvalidPayloadException, IOException {
        // lets try use the Sink to unmarshall it
        Transform transformer = getTransform();
        Element input = transformer.getInput(0);
        ArtixDSSource source = new ArtixDSSource(input);
        return source.parseDataObject(exchange);
    }
}
