//Einstein.java
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.awt.Image;
import Reality;
import PerpRods;
import EinsteinObject;
import SpacePanel;	
import Stars;
import EINtutor;
import CarLight;
				
public class Einstein extends Applet implements Runnable
{
	Thread animation;
	static int REFRESH_RATE = 50;
	Graphics offscr,offscr2,obj;
	Image image,image2,obj_im;
	int width= 500, height=300;
	
	public Reality reality;
	
	Panel ButtonPanel,LeftPanel,RightPanel;
	Button START,STEP,RESET,b;
	boolean started = false;
	boolean stepped = false;
	boolean pushed = false;
	double t_inc = 1;
	public int topValue;
	Scrollbar top_scr;
	Choice exp_choice;
	SpacePanel space=null;
	TimePanel time = null;
	Label top_lab;
	Button flipSwitch;
	Label flipLabel;
	boolean frame = Reality.OBSERVER_FRAME;
	EinsteinObject mover;
	EINtutor EINtut;
	public void PanelInit()
	{
		Font little = new Font("Serif",Font.PLAIN,10);
		Font temp = getFont();
		setFont(little);
		LeftPanel = new Panel(new GridBagLayout());
		RightPanel = new Panel(new GridBagLayout());
		LeftPanel.setBackground(Color.white);
		RightPanel.setBackground(Color.white);
		GridBagConstraints c = new GridBagConstraints();
		top_lab = new Label("Object v= .00 c",Label.RIGHT);
		top_lab.setForeground(Color.blue);
		top_scr = new Scrollbar(Scrollbar.HORIZONTAL,0,1,0,99);
		top_scr.addAdjustmentListener(new AdjustmentListener()
			{
				public void adjustmentValueChanged(AdjustmentEvent ae)
				{
					topValue = ae.getValue();
					double value = .01 * topValue;
					if (mover != null)
					{
						mover.setV(-value);
						reality.setVelocity(value);
					}
					Double d = new Double(value);
					String sv = d.toString();
					int start =0,end = sv.length();
					if (sv.charAt(0) == '0') start = 1;
					if ((end - start) > 3) end = start + 3;
					top_lab.setText("Object v= "+sv.substring(start,end)+" c");
					if (time != null) time.repaint();
					if (space != null) space.repaint();
				}
			}
									);
		c.fill = GridBagConstraints.HORIZONTAL;
		c.insets = new Insets(5,5,5,5);
		c.gridx =0; c.gridy=0;c.gridwidth=3;c.gridheight=1;
		c.weightx = 0; c.weighty=0;
		LeftPanel.add(top_lab,c);
		c.gridx = 3; c.gridwidth=7;c.weightx = 1;
		LeftPanel.add(top_scr,c);
		c.gridx = 0; c.gridwidth=10;
		c.fill = GridBagConstraints.BOTH;
		c.insets = new Insets(0,5,5,5);
		space = new SpacePanel(-30,5,60,10,this);
		time = new TimePanel(this);
		c.gridy=1; c.gridheight=10; c.weightx = 1; c.weighty=1;
		LeftPanel.add(space,c);
		RightPanel.add(time,c);
		c.fill = GridBagConstraints.HORIZONTAL;
		c.insets = new Insets(0,5,5,5);
		flipSwitch = new Button("Switch Frames");
		flipLabel = new Label("In Observer's Frame");
		flipLabel.setForeground(Color.red);
		flipSwitch.addActionListener(new ActionListener()
			{
				public void actionPerformed(ActionEvent ae)
				{
					if (frame == Reality.OBJECT_FRAME)
					{
						frame = Reality.OBSERVER_FRAME;
						space.xstart = (int)(reality.theirX)+space.ixstart;
						space.s = new Stars(space);
						flipLabel.setText("In Observer's Frame");
						flipLabel.setForeground(Color.red);
					}
					else
					{
						frame = Reality.OBJECT_FRAME;
						space.xstart = (int)(mover.getReality().myX)+space.ixstart;
						space.s = new Stars(space);
						
						flipLabel.setText("In Object's Frame");
						flipLabel.setForeground(Color.blue);
					}
					flipLabel.repaint();
					if (!started)
					{
						time.repaint();
						space.repaint();
					}
				}
			});
		c.gridy = 12; c.gridheight =1;
		c.weightx = 0; c.weighty=0;
		c.gridwidth=4;
		LeftPanel.add(flipSwitch,c);
		c.insets = new Insets(0,5,5,5);
		c.gridx = 4; c.gridwidth=6;c.weightx=1;
		LeftPanel.add(flipLabel,c);
		c.gridx = 0; c.gridwidth=10;
		exp_choice = new Choice();
		exp_choice.add("Exp 1: Perpendicular Rods");
		exp_choice.add("Exp 2: Flying Clocks");
		exp_choice.add("Exp 3: A Light Clock");
		exp_choice.add("Exp 4: Moving Michelson-Morley");
		exp_choice.add("Exp 5: Barn & Ladder Paradox");
		exp_choice.add("Exp 6: Car Headlight Experiment");
		exp_choice.addItemListener(new ItemListener()
			{
				public void itemStateChanged(ItemEvent ie)
				{
					Choice ctemp = (Choice)ie.getSource();
					int choiceNum = ctemp.getSelectedIndex();
					reset();
					initMover(choiceNum);
				}
			}
							   );					
		c.gridy = 13;
		LeftPanel.add(exp_choice,c);
		ButtonPanelInit();
		c.insets = new Insets(0,0,0,0);
		RightPanel.add(ButtonPanel,c);
		setFont(temp);
	}
	
	public void initMover(int c)
	{
		switch(c)
		{
		case 0:	
			mover = new PerpRods(topValue,this);
			break;
		case 1:
			mover = new FlyingClocks(topValue,this);
			break;
		case 2:
			mover = new LightClock(topValue,this);
			break;
		case 3:
			mover = new MM(topValue,this);
			break;
		case 4:
			mover = new BarnLadder(topValue,this);
			break;
		case 5:
			mover = new CarLight(topValue,this);
			mover.setCar(getImage(getDocumentBase(),"images/carsmall.gif"));
			break;
		default:
			mover = new EinsteinObject(topValue,this);
		}
		repaint();
		time.repaint();
		space.repaint();
	}
	
	public void ButtonPanelInit()
	{
		ButtonPanel = new Panel(new FlowLayout(FlowLayout.CENTER,5,5));
		ButtonPanel.setBackground(Color.white);
		START = new Button("Start");
		START.addActionListener(new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					if (!started)
					{
						started = true;
						START.setLabel("Stop");
						top_scr.setEnabled(false);
					}
					else
					{
						started = false;
						stepped = false;
						START.setLabel("Start");
					}
					time.repaint();
					space.repaint();
				}
			}				   );
		ButtonPanel.add(START);
		STEP  = new Button("Step");
		STEP.addActionListener(new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					if (started)
					{
						START.setLabel("Start");
						started = false;
					}
					else
					{
						top_scr.setEnabled(false);
					}
					stepped = true;
					time.repaint();
					space.repaint();
				}
			}	
							   );
		ButtonPanel.add(STEP);
		RESET = new Button("Reset");
		RESET.addActionListener(new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					reset();
				}
			}	
							   );
		ButtonPanel.add(RESET);
		b = new Button("Java TA");
		b.addActionListener(new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
						Button buttTarget  = (Button)e.getSource();
						buttTarget.setEnabled(false);
						buttTarget.setVisible(false);
						pushed = true;
				}
			}
							);
		ButtonPanel.add(b);
	}
	
	public void reset()
	{
		started = false;
		top_scr.setEnabled(true);
		START.setLabel("Start");
		space.init();
		reality = new Reality(0);
		initMover(exp_choice.getSelectedIndex());
		topValue = 0;
		top_scr.setValue(0);
		top_lab.setText("Object v= .00 c");
		initMover(exp_choice.getSelectedIndex());
		time.offsetX = 0; time.offsetY = 0;
		repaint();
		time.repaint();
		space.repaint();
	}
	public void init()
	{
		topValue = 0;
		mover = new PerpRods(topValue,this);
		image = createImage(300,300);
		offscr= image.getGraphics();
		image2 = createImage(300,300);
		offscr2= image2.getGraphics();
		setLayout(new GridLayout(1,2,0,0));
		PanelInit();
		add(LeftPanel);
		add(RightPanel);
		reality = new Reality(0);
	}

	public Reality getReality()
	{
		return reality;
	}
	
	public void start()
	{
		animation = new Thread(this);
		if (animation != null)
		{
			animation.start();
		}

	}
	
	public void run()
	{
		while (true)
		{
			repaint();
			//Rectangle r = space.getBounds();
			if (started || stepped) 
			{
				stepped = false;
				if (mover != null)
				{
					space.s.move(frame, mover.getV());
					mover.Increment();
				}
				reality.Increment();
				space.repaint();
				time.repaint();
			}
			if (pushed)
			{
				EINtut = new EINtutor(this);
				b.setLabel("TA on");
				pushed = false;
				b.setEnabled(true);
				b.setVisible(true);
			}
			try {
					Thread.sleep(REFRESH_RATE);
			}
			catch (Exception exc) {};
		}
	}
	
	
	
	public void stop()
	{
		if (animation != null)
		{
			animation.stop();
			animation= null;
		}
	}
}