/*
 *  Copyright (C) 2003  Jens Kanschik,
 * 	mail : jensKanschik@users.sourceforge.net
 *
 *  Part of <hypergraph>, an open source project at sourceforge.net
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

package hypergraph.applications.hexplorer;


import hypergraph.graphApi.Graph;
import hypergraph.graphApi.GraphSystem;
import hypergraph.graphApi.GraphSystemFactory;
import hypergraph.graphApi.Node;
import hypergraph.graphApi.algorithms.GraphUtilities;
import hypergraph.graphApi.io.GraphWriter;
import hypergraph.graphApi.io.GraphXMLWriter;
import hypergraph.graphApi.io.SAXReader;
import hypergraph.visualnet.ArrowLineRenderer;

import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.URL;

import javax.swing.JApplet;
import javax.swing.JOptionPane;

import org.xml.sax.SAXException;

/**
 * @author Jens Kanschik
 *
 * To change the template for this generated type comment go to
 * Window&gt;Preferences&gt;Java&gt;Code Generation&gt;Code and Comments
 */
public class HExplorerApplet extends JApplet {
	/** Stores the graph that the applet shows. */
	private GraphPanel graphPanel;

	public GraphPanel getGraphPanel() {
		return graphPanel;
	}
	/**@inheritDoc */
	public void init() {
		String file = getParameter("file");
		String value = getParameter("value");
		GraphSystem graphSystem = null;
		try {
			graphSystem = GraphSystemFactory.createGraphSystem("hypergraph.graph.GraphSystemImpl", null);
		} catch (Exception e) {
			e.printStackTrace();
			System.exit(8);
		}
		Graph graph = null;
		URL url = null;
		try {
			SAXReader reader = null ;
			if((null != file) && (!"".equals(file))) {
				//url = new URL(getCodeBase(), file);
				url = new URL("" + getCodeBase() + file) ;
				reader = new SAXReader(graphSystem, url);
			} else {
				reader = new SAXReader(graphSystem, value, new URL(getCodeBase(), ""));
			}
			ContentHandlerFactory ch = new ContentHandlerFactory();
			ch.setBaseUrl(getCodeBase());
			reader.setContentHandlerFactory(ch);
			graph = reader.parse();
		} catch (FileNotFoundException fnfe) {
			JOptionPane.showMessageDialog(null,
				"Could not find file " + url.getFile() + ". \n" +
				"Start applet with default graph", "File not found", JOptionPane.ERROR_MESSAGE);
			System.out.println("Exception : " + fnfe);
			fnfe.printStackTrace(System.out);
		} catch (SAXException saxe) {
			JOptionPane.showMessageDialog(null,
				"Error while parsing file" + url.getFile() + ". \n" +
				"Exception : " + saxe + ". \n" +
				"Start applet with default graph", "Parsing error", JOptionPane.ERROR_MESSAGE);
			System.out.println("Exception : " + saxe);
			saxe.getException().printStackTrace();
			saxe.printStackTrace(System.out);
		} catch (Exception e) {
            java.io.StringWriter sw = new java.io.StringWriter() ;
            java.io.PrintWriter pw = new java.io.PrintWriter(sw) ;
            e.printStackTrace(pw) ;
            String stackTrace = sw.getBuffer().toString() ;
			JOptionPane.showMessageDialog(null,
				"General error while reading file " + url + ". \n" +
				"Exception : " + e + ". \n" +
				stackTrace + "\n" +
				"Start applet with default graph", "General error", JOptionPane.ERROR_MESSAGE);
			System.out.println(url);
			System.out.println("Exception : " + e);
			e.printStackTrace(System.out);
		}

		if (graph == null) {
			graph = GraphUtilities.createTree(graphSystem, 2, 3);
		}

		graphPanel = new GraphPanel(graph, this);
		file = getParameter("properties");
		if (file != null)
			try {
				url = new URL(getCodeBase(), file);
				graphPanel.loadProperties(url.openStream());
			} catch (FileNotFoundException fnfe) {
				JOptionPane.showMessageDialog(null,
					"Could not find propertyfile " + url.getFile() + ". \n" +
					"Start applet with default properties", "File not found", JOptionPane.ERROR_MESSAGE);
			} catch (Exception e) {
	            java.io.StringWriter sw = new java.io.StringWriter() ;
	            java.io.PrintWriter pw = new java.io.PrintWriter(sw) ;
	            e.printStackTrace(pw) ;
	            String stackTrace = sw.getBuffer().toString() ;
				JOptionPane.showMessageDialog(null,
					"General error while reading file " + url.getFile() + ". \n" +
					"Exception : " + e + ". \n" +
					stackTrace + "\n" +
					"Start applet with default properties", "General error", JOptionPane.ERROR_MESSAGE);
				System.out.println(url);
				System.out.println("Exception : " + e);
				e.printStackTrace(System.out);
			}

		String center = getParameter("center");
		if (center != null) {
			Node n = (Node) graph.getElement(center);
			if (n != null)
				graphPanel.centerNode(n);
		}
		graphPanel.setLineRenderer(new ArrowLineRenderer());
		
		getContentPane().add(graphPanel);
	}
	
	public String getGraphXML() {
		try {
			OutputStream os = new ByteArrayOutputStream();
			GraphWriter graphWriter = new GraphXMLWriter(new OutputStreamWriter(os));
			graphWriter.write(getGraphPanel().getGraph());
			return os.toString();
		} catch (IOException ioe) {
			ioe.printStackTrace();
			return ioe.toString();
		}
	}
}