/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2011 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.operator.tools;

import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import com.rapidminer.tools.XMLSerialization;

/**
 * 
 * @author Simon Fischer
 *
 */
class JavaBinaryBodySerializer implements BodySerializer {

	@Override
	public Object deserialize(InputStream in) throws IOException {
		ObjectInputStream oin = new RMObjectInputStream(in);
		try {
			return oin.readObject();
		} catch (ClassNotFoundException e) {
			throw new IOException("Deserialized unknown class: "+e, e);
		}
	}

	@Override
	public void serialize(Object object, OutputStream out) throws IOException {
		ObjectOutputStream oout = new ObjectOutputStream(out);
		oout.writeObject(object);
	}		
}
class XMLBodySerializer implements BodySerializer {
	@Override
	public Object deserialize(InputStream in) throws IOException {
		XMLSerialization xmlSerialization = XMLSerialization.getXMLSerialization();
		if (xmlSerialization == null) {
			throw new IOException("XML Serialization not initialized.");
		}
		return xmlSerialization.fromXML(in);
	}
	@Override
	public void serialize(Object object, OutputStream out) throws IOException {
		XMLSerialization xmlSerialization = XMLSerialization.getXMLSerialization();
		if (xmlSerialization == null) {
			throw new IOException("XML Serialization not initialized.");
		}
		xmlSerialization.writeXML(object, out);
	}		
}

class GZippedXMLBodySerializer extends XMLBodySerializer {
	@Override
	public Object deserialize(InputStream in) throws IOException {
		return super.deserialize(new GZIPInputStream(in));
	}
	@Override
	public void serialize(Object object, OutputStream out) throws IOException {
		super.serialize(new GZIPOutputStream(out), out);
	}		
}

/** Encapsulates some standard ways to serialize and deserialize objects from streams.
 * 
 * NOTE: When adding new enum constants, don't change the ordering of the old, since the
 *  ordinal value will be used to identify the serialization type.
 * @author Simon Fischer
 *
 */
public enum SerializationType {
	
	/** Plain binary java serialization using Object{In/Out}putStream. */
	JAVA_BINARY(new JavaBinaryBodySerializer()),
	
	/** Uses xstream XML serialization. */
	XML(new XMLBodySerializer()),
	
	/** Uses xstream XML serialization wrapped in a GZip stream. */
	XML_ZIPPED(new GZippedXMLBodySerializer()),
	
	STREAMED_EXAMPLE_SET_DENSE(new StreamedExampleSetBodySerializer(ExampleSetToStream.VERSION_1)),
	
	STREAMED_EXAMPLE_SET_DENSE_2(new StreamedExampleSetBodySerializer(ExampleSetToStream.VERSION_2)),
	
	STREAMED_EXAMPLE_SET_DENSE_3(new StreamedExampleSetBodySerializer(ExampleSetToStream.VERSION_3));
	
	public static SerializationType STREAMED_EXAMPLE_SET_DENSE_CURRENT_VERSION = STREAMED_EXAMPLE_SET_DENSE_3; 
	
	private BodySerializer bodySerializer;
	
	private SerializationType(BodySerializer bodySerializer) {
		this.bodySerializer = bodySerializer;
	}

	public BodySerializer getBodySerializer() {
		return bodySerializer;
	}
}