/*
 *  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.repository.resource;

import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;

import com.rapidminer.operator.IOObject;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.ports.metadata.AttributeMetaData;
import com.rapidminer.operator.ports.metadata.ExampleSetMetaData;
import com.rapidminer.operator.ports.metadata.MetaData;
import com.rapidminer.operator.tools.IOObjectSerializer;
import com.rapidminer.repository.IOObjectEntry;
import com.rapidminer.repository.RepositoryException;
import com.rapidminer.tools.ProgressListener;


/**
 * 
 * @author Simon Fischer
 *
 */
public class ResourceIOObjectEntry extends ResourceDataEntry implements IOObjectEntry {

	private MetaData metaData;

	protected ResourceIOObjectEntry(ResourceFolder parent, String name, String resource, ResourceRepository repository) {
		super(parent, name, resource, repository);
	}

	@Override
	public String getDescription() {
		return null;
	}

	@Override
	public String getType() {
		return IOObjectEntry.TYPE_NAME;
	}

	@Override
	public IOObject retrieveData(ProgressListener l) throws RepositoryException {
		if (l != null) {
			l.setTotal(100);
			l.setCompleted(10);
		}		
		InputStream in = ResourceIOObjectEntry.class.getResourceAsStream(getResource()+".ioo");
		if (in != null) {
			try {
				return (IOObject)IOObjectSerializer.getInstance().deserialize(in);
			} catch (Exception e) {
				throw new RepositoryException("Cannot load data from '"+getResource()+".ioo': "+e, e);
			}
		} else {
			throw new RepositoryException("Resource '"+getResource()+".ioo does not exist'.");
		}		
	}

	@Override
	public MetaData retrieveMetaData() throws RepositoryException {
		if (metaData == null) {
			String mdResource = getResource() + ".md";
			InputStream in = ResourceIOObjectEntry.class.getResourceAsStream(mdResource);
			if (in != null) {
				ObjectInputStream objectIn = null;
				try {
					objectIn = new ObjectInputStream(in);
					this.metaData = (MetaData)objectIn.readObject();
					if (this.metaData instanceof ExampleSetMetaData) {
						for (AttributeMetaData amd : ((ExampleSetMetaData) metaData).getAllAttributes()) {
							if (amd.isNominal()) {
								amd.shrinkValueSet();
							}
						}
					}
					objectIn.close();
				} catch (Exception e) {
					throw new RepositoryException("Cannot load meta data from '"+mdResource+"': "+e, e);
				} finally {
					if (objectIn != null) {
						try {
							objectIn.close();
						} catch (IOException e) { }
					}
				}
			} else {
				throw new RepositoryException("Meta data resource '"+mdResource+" does not exist'.");
			}	
		}
		return metaData;
	}

	@Override
	public void storeData(IOObject data, Operator callingOperator, ProgressListener l) throws RepositoryException {
		throw new RepositoryException("Repository is read only.");
	}

	@Override
	public boolean willBlock() {
		return metaData == null;
	}

	@Override
	public Class<? extends IOObject> getObjectClass() {
		try {
			return retrieveMetaData().getObjectClass();
		} catch (RepositoryException e) {
			return null;
		}
	}
}