/*
 * XLogo4Schools - A Logo Interpreter specialized for use in schools, based on XLogo by Loic Le Coq
 * Copyright (C) 2013 Marko Zivkovic
 * Contact Information: marko88zivkovic at gmail dot com
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 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 General
 * Public License for more details. You should have received a copy of the
 * GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 * 
 * This Java source code belongs to XLogo4Schools, written by Marko Zivkovic
 * during his Bachelor thesis at the computer science department of ETH Zurich,
 * in the year 2013 and/or during future work.
 * 
 * It is a reengineered version of XLogo written by Loic Le Coq, published
 * under the GPL License at http://xlogo.tuxfamily.org/
 * 
 * Contents of this file were entirely written by Marko Zivkovic
 */

package xlogo.storage;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

/**
 * The base class for anything that must be stored persistently.
 * @author Marko Zivkovic
 */
public abstract class StorableObject extends Storable implements Serializable {
	
	private static final long	serialVersionUID	= -1738873382662156052L;
	
	private static Logger		logger				= LogManager.getLogger(StorableObject.class.getSimpleName());
	
	/*
	 * PATH BUILDERS
	 */
	
	/**
	 * @param c
	 * @return X4S_ClassName.ser
	 */
	@SuppressWarnings("rawtypes")
	public static String getX4SObjectFileName(Class c) {
		return "X4S_" + c.getSimpleName();
	}
	
	/**
	 * This naming scheme shall be used to store Objects in XLogo4Schools
	 * @param dir - where the instance of c should be stored.
	 * @param c - Class of Objects to be stored persistently
	 * @return pathname for dir/X4S_ClassName.ser
	 */
	@SuppressWarnings("rawtypes")
	public static String getFilePath(File dir, Class c) {
		return dir.toString() + File.separator + getX4SObjectFileName(c);
	}
	
	/**
	 * @param dir
	 * @param c
	 * @return file for pathname as defined by {@link #getFilePath(File, Class)}
	 */
	@SuppressWarnings("rawtypes")
	public static File getFile(File dir, Class c) {
		String path = getFilePath(dir, c) + ".ser";
		return new File(path);
	}
	
	@Override
	public String getFileNameExtension() {
		return ".ser";
	}
	
	/**
	 * Constructor. The FileName will be equal to 
	 */
	public StorableObject() {
		setFileName(getX4SObjectFileName(getClass()));
	}
	
	/*
	 * Store & Load
	 */
	
	public void store() throws IOException {
		if (isDirty() && !isVirtual())
			storeCopyToFile(getFilePath());
	}
	
	public void storeCopyToFile(File file) throws IOException, IllegalArgumentException {
		if (file == null)
			throw new IllegalArgumentException("file must not be null.");
		
		logger.trace("Storing Object to " + file.getAbsolutePath());
		
		if (!isVirtual()) {
			mkParentDirs(file);
			FileOutputStream fileOut = new FileOutputStream(file);
			ObjectOutputStream out = new ObjectOutputStream(fileOut);
			out.writeObject(this);
			out.close();
			fileOut.close();
		}
		makeClean();
	}
	
	/**
	 * Load a Storable object from the specified file
	 * @param file
	 * @return the loaded Storable
	 * @throws IOException
	 * @throws ClassNotFoundException
	 * @throws ClassCastException
	 */
	public static StorableObject loadObject(File file) throws IOException, ClassNotFoundException, ClassCastException {
		logger.trace("Loading Object from " + file.getAbsolutePath());
		
		FileInputStream fileIn = new FileInputStream(file);
		ObjectInputStream in = new ObjectInputStream(fileIn);
		Object object = in.readObject();
		in.close();
		fileIn.close();
		
		if (!(object instanceof StorableObject))
			throw new ClassCastException("The specified file (" + file.toString()
					+ ") does not contain an instance of Storable: " + object.getClass().toString());
		
		StorableObject storable = (StorableObject) object;
		storable.makeClean();
		return storable;
	}
	
}