//Java Scratch Off Applet
// Written by Dr. Roger Webster 

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.applet.Applet;

public class scratchoff extends Applet implements ActionListener   
{
	Frame window;
      TextArea textarea = new TextArea(5, 80);
      checkers mycheckers;
	boolean mousedragging = false;
	Image img;
	Panel mypanel = new Panel();
	Button bigger = new Button("make larger scratches");
	Button smaller = new Button("make smaller scratches");

  public void init() 
  { 
       img = getImage( getDocumentBase(),  "ms.jpg" );

	window = new Frame ("Webster's Java Scratch off Window");
	window.setSize (500, 500);
      textarea.setFont(new Font("Helvetica", Font.PLAIN, 12));
      textarea.setEditable(false);
	//mypanel.add(textarea);        
	bigger.addActionListener(this);
	smaller.addActionListener(this);
	mypanel.add(bigger);
	mypanel.add(smaller);
	mypanel.setBackground(Color.red);

	window.add("North", mypanel);
	textarea.appendText("hello Java Scratch Off Players\n");
      mycheckers = new checkers(img);
	window.add("Center", mycheckers);
	window.show();
  }

  	public void stop() 
  	{
		window.dispose();
	}

	public void actionPerformed(ActionEvent event) 
	{
        Component source=(Component)event.getSource();

        	if (source == bigger ) 
		{
          	 	textarea.appendText("size is now bigger  !\n");			
			mycheckers.bigger();

        	} 

		if (source == smaller ) 
		{
          	 	textarea.appendText("size is now smaller !\n");			
			mycheckers.smaller();

        	} 
	
	}


class checkers extends Canvas 
{ 
	int grid = 8;
	int currentx=0, currenty=0;
	Color grey = new Color(165,165,165);//Board colors
	Color tan = new Color(255,255,204);	//Board colors
	int nextx=0;
	int nexty=0;
	Graphics og;
	Image offScrImg;
	int imgWidth=20; // set this for how big you want to scratch off
	int imgHeight=20; // set this for how big you want to scratch off
	int width;
	int height;
	Image myimage;

  // Initialization function
  	checkers(Image img) 
	{
 		super();
		this.myimage = img;
		
		textarea.appendText("start sratching  !\n");			
		width = size().width/grid;
		height = size().height/grid;
  	}
 
	void cliptoaffectedarea (Graphics g, int oldx, int oldy, int newx, int newy, int width, int height)
	{
		int x = Math.min(oldx, newx);
		int y = Math.min(oldy, newy);
		int w = ( Math.max(oldx, newx) + width) - x;
		int h = ( Math.max(oldy, newy) + height) - y;
		g.clipRect(x,y,w,h);
	}

     	public void update( Graphics g )
   	{
 		if (offScrImg == null)
			offScrImg = createImage(size().width, size().height);
		og = offScrImg.getGraphics();
 		int lastx = currentx;
		int lasty = currenty;
		currentx = nextx;
		currenty = nexty;
		cliptoaffectedarea (og, lastx, lasty, currentx, currenty, imgWidth, imgHeight);
	//	cliptoaffectedarea (g, lastx, lasty, currentx, currenty, imgWidth, imgHeight);
		paint(og);
		g.drawImage(offScrImg, 0, 0, this);
		og.dispose();
   	}
 
   // display the image
   public void paint( Graphics g )
   {
	 	boolean shade = false;
		int PieceType;

   		width = size().width/grid;
		height = size().height/grid;
	
		for (int y=0;y<=grid;y++)
			for (int x=0; x <= grid; x++)
			{
				g.setColor ( (shade = !shade) ? tan :grey);
				g.fillRect ( x * width, y * height, width, height);
			}
		        
		// draw the original image
      	g.drawImage( myimage, 0, 0, this );

     } //end of paint()

	public void bigger ()
	{
		imgHeight = imgHeight + 10;			
		imgWidth = imgWidth + 10;	
		textarea.appendText("size is now " + imgHeight + "  !\n");			
			
	}

	public  void smaller ()
	{
		imgHeight = imgHeight - 10;			
		imgWidth = imgWidth - 10;	
		textarea.appendText("size is now " + imgHeight + "  !\n");			
			
	}

	public boolean mouseDown (Event e, int x, int y)
	{
		
		nextx = x;
		nexty = y;		
		currentx = x;
		currenty = y;
		mousedragging = true;
		repaint();
						
		return true;
	}	
	
	public boolean mouseUp (Event e, int x, int y)
	{
	
		mousedragging = false;
		return true;
	}	
	
	public boolean mouseDrag(Event e, int x, int y)
	{
		nextx = x;
		nexty = y;		
		currentx = x;
		currenty = y;
		mousedragging = true;
		repaint();
		
		return true;
	}
}

}