/*
	Trivial applet that illustrates how to use Leigh Brookshaw's Graph Package
	to plot random data.
*/

import java.awt.*;
import java.applet.Applet;
import java.awt.event.*;
import java.io.*;
import graph.*;
import java.net.URL;


public class RunnableApplet extends Applet implements Runnable
{
	boolean			runningSafe;		// if true, we don't have access to the file system
	boolean			running;			// are we currently running?
	Thread			relaxer;			// magic used to implement the Runnable interface
	
	// User interface objects
	
	Panel			settings;			// controls go into this Panel
	ValueControl	timeStep;			// see ValueControl.java
	TextArea		messages;
	Checkbox		fixedStep;
	Button			starter;
	
	Graph2D 		graph;				// major feature of the GUI
	DataSet 		dataSet;
	Axis			xaxis, yaxis;
	double			data[];
	Markers 		markers;
	URL 			markersURL;

	Graphics		osg = null;			// these are used to implement double-buffering of the graph
	Image			osi = null;			// to make updates look smooth
	int				iwidth = 0;
	int				iheight = 0;
	int				updateInterval = 10;
	int				count = 0;			// how many times through the iterate function
	
	
	// methods required to implement the Runnable interface

	public void start() {
		relaxer = new Thread( this );
		relaxer.start();
	}
	
	public void stop() {
		relaxer.stop();
	}

	public void run( ) {
		while ( true ) {
			try {
				if ( running )
					{ iterate();	}
				try { Thread.sleep( 1 ); }
				catch (InterruptedException e) { break;	}
			}
			catch ( Exception ee ) {
				System.out.println( "Caught exception " + ee );
				break;
			}
		}
	}

	public void init() {
		setSize(800, 600);
		running = false;
		
		// Do we have access to the file system?
		try {
			File f = new File( System.getProperty( "user.dir" ), "junk" );
			runningSafe = false;
		}
		catch ( Exception e ) {
			runningSafe = true;
		}
		
		
		// We will use the most powerful layout manager to arrange items in
		// our applet panel. With the GridBagLayout, you add items by passing
		// a GridBagConstraints object, which describes where to put each item.
		
		setLayout( new GridBagLayout( ) );
		GridBagConstraints gbc = new GridBagConstraints();
		// Initialize common fields of the GridBagConstraints
		gbc.fill = gbc.BOTH;					// components grow horizontally
		gbc.insets = new Insets(2, 2, 2, 2);	// 2-pixel margins on all sides
		gbc.gridx = 0;
		gbc.gridy = 0;
		gbc.gridwidth = 2;
		gbc.gridheight = 2;
		gbc.weightx = gbc.weighty = 0.0;
		
		// Prepare the graph
		graph = new Graph2D();
		graph.borderTop = 10;
		graph.borderRight = 10;
		graph.borderLeft = 10;
		graph.square = true;
		graph.setSize( 350, 350 );

		add( graph, gbc );			// add the graph at the top left
				
		
		/*
		**      Load a file containing Marker definitions
		*/
        try {
           markersURL = new URL(getDocumentBase(), "marker.txt" );
           markers = new Markers(markersURL);

        } catch(Exception e) {
           System.out.println("Failed to create Marker URL!");
           System.out.println( "Markers file was supposed to be marker.txt" );
        }
 
        graph.setMarkers(markers);
		
		
		settings = new Panel();
		settings.setLayout( new GridBagLayout() );
		gbc.gridx = 0;
		gbc.gridy = 2;
		gbc.gridwidth = 4;
		gbc.gridheight = 1;
		add( settings, gbc );			// add the panel to the applet
		
		gbc.fill = gbc.NONE;			// components don't grow
		gbc.gridx = 0;
		gbc.gridy = 1;
		gbc.gridwidth = 1;
		gbc.gridheight = 1;
		gbc.weightx = gbc.weighty = 0.0;

		starter = new Button( "Start" );
		settings.add( starter, gbc );
		starter.setActionCommand( "start" );	// I don't think this is necessary, but...
		
		starter.addActionListener( new ActionListener() {
			public void actionPerformed( ActionEvent e ) {
				startStop();			// when pressed, call this function
			}});

		gbc.gridx++;					// move to next position in the grid
		fixedStep = new Checkbox( "Fix step size" );
		settings.add( fixedStep, gbc );
		fixedStep.setState( true );		// make sure the box is checked initially
		
		timeStep = new ValueControl( this, "Time step (y)", 0.0, 1, 0.02 );
		timeStep.setAction( new ValueControlAction() {
			public void action( ValueControl vc ) {
				SetTimeStep( vc.value() );
			}} );
		gbc.gridx++;
		settings.add( timeStep, gbc );

		messages = new TextArea( "", 4, 30, TextArea.SCROLLBARS_NONE );
		messages.setFont( new Font( "SansSerif", Font.PLAIN, 9 ) );
		gbc.gridx++;
		gbc.gridy = 0;
		gbc.gridheight = 3;
		settings.add( messages, gbc );

	}
	
	public void paint( Graphics g ) {
	}
	
	public void startStop() {
		if ( running )	starter.setLabel( "Start" );
		else starter.setLabel( "Stop" );
		
		if ( !running )	// we are stopped and need to start up
			startUp();	// this will set running to true
		else
			running = false;
	}
	
	public void startUp() {

		double [] data = new double[2];
		double [] newpoint = new double[2];
		
		
		double [] initial1 = { 1.0, 1.0, 5.0, 5.0 };
		
		try {
			if ( dataSet == null ) {
				
				dataSet = graph.loadDataSet( initial1, 2 );	// two points
				dataSet.linestyle = 1;
				dataSet.linecolor = new Color( 255, 0, 0 );
				dataSet.marker = 1;
				dataSet.drawLastOnly = true;					// modification to the DataSet class
				
				xaxis = graph.createAxis( Axis.BOTTOM );
				xaxis.attachDataSet( dataSet );
				xaxis.setTitleText( "X axis" );
				
				yaxis = graph.createAxis( Axis.LEFT );
				yaxis.attachDataSet( dataSet );
				yaxis.setTitleText( "Y axis" );
			}
			else		// we're restarting
			{
				dataSet.deleteData();
				dataSet.append( initial1, 2 );
			}
		}
		catch ( Exception e ) {
			System.out.println( "Caught error setting data: " + e );
			e.printStackTrace();
		}
		count = 2;
		running = true;
		iterate();
	}
		
	public void iterate() {
		count++;
		if ( count > 100000 )	// we're getting full!
			startStop();
		try {
			double [] newpoint = new double[2];
			newpoint[0] = Math.random() * 5;
			newpoint[1] = Math.random() * 5;
			dataSet.append( newpoint, 1 );	// add the point
		}
		catch ( Exception e ) {
			System.out.println( e );
		}
			
		if ( count % updateInterval == 0 ) {
			Graphics g = graph.getGraphics();
			if ( osi == null || iwidth != graph.size().width || iheight !=
				graph.size().height ) {
				iwidth = graph.size().width;
				iheight = graph.size().height;
				osi = graph.createImage( iwidth, iheight );
				osg = osi.getGraphics();
			}
			
			osg.setColor(this.getBackground());
			osg.fillRect(0,0,iwidth,iheight);
	 		osg.setColor(g.getColor());
			osg.clipRect(0,0,iwidth,iheight);
			graph.update(osg);
			g.drawImage(osi,0,0,graph);

			String s = "count = " + count;
			messages.replaceRange( s, 0, 500 );	// set the information message
		}
	}

	public void SetTimeStep( double dt ) {
		if ( running )
			System.out.println( "I should set the time step to " + dt );
	}
}