// mouse incs, shift-drag decs
// reset from keyboard
// no need to reset at first anymore
// why doesn't netscape 4.0.5 with awt 1.1.5 deal?

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

public class Life extends Applet
{
  myCanvas cvs;
  Applet thisApplet;

  int delay = 80;

  int last_x, last_y, numImgs=9+4;

  public static final boolean glider[/*dir*/][/*x*/][/*y*/] = 
  {{{false,false,true}, {true,false,true}, {false,true,true}}, //SE
   {{true,true,true}, {false,false,true}, {false,true,false}}, //SW
   {{true,true,false}, {true,false,true}, {true,false,false}}, //NW
   {{false,true,false}, {true,false,false}, {true,true,true}}}; //NE

  public static final int SE = 0;
  public static final int SW = 1;
  public static final int NW = 2;
  public static final int NE = 3;
  
  int[][] res = new int[24][24];

  Image[] imgs, gliderImgs, theImg;

  MediaTracker mt;

  class myCanvas extends Canvas
  {
    Image img;

    public myCanvas()
      {
        super();
	//	setSize(w,h);
	img = null;
      }
    
    public void update(Graphics g)
      { paint(g); }

    public void paint()
      { paint(getGraphics()); }
    
    public void paint(Graphics g)
      {
        if ((g!=null)&&(img!=null))
	  g.drawImage(img, 0,0, this);
      }
  }

  public void init()
    {
      thisApplet = this;

      images();
      gui();
      listeners();
    }

  void images()
    {
      for (int i=0; i<24; i++)
	for (int j=0; j<24; j++)
	  res[i][j] = 0;

      mt = new MediaTracker(thisApplet);

      imgs = new Image[9];
      for(int i=0; i<9; i++)
	{
	  imgs[i] = getImage
	    (getDocumentBase(), "imgs/hand" + i + ".jpeg");
	  mt.addImage(imgs[i],i);

	}

      gliderImgs = new Image[4];
      for(int i=0; i<4; i++)
	{
	  gliderImgs[i] = getImage
	    (getDocumentBase(), "imgs/glider" + i + ".jpeg");
	  mt.addImage(gliderImgs[i],9+i);
	}

    }

  void gui()
    {
      thisApplet.setLayout(new BorderLayout(0,0));
      thisApplet.setBackground(Color.darkGray);

      cvs = new myCanvas();
      cvs.setSize(64+256+64, 64+256+64);
      cvs.setBackground(Color.darkGray);

      thisApplet.add(cvs, "Center");

      validate();
    }

  void listeners()
    {
      cvs.addMouseListener
	(new MouseAdapter()
	 {
	   public void mouseEntered(MouseEvent e) {
	     cvs.requestFocus();
	   }

	   public void mousePressed(MouseEvent e)
	     {
	       last_x = e.getX();
	       last_y = e.getY();
	     }
	   
	   public void mouseReleased(MouseEvent e)
	     {
	       if ((last_x>63) && (last_x < 256+64)
		   && (last_y>63) && (last_y < 256+64))
		 return;
	       
	       boolean[][] gliderArray = new boolean[24][24];
	       boolean[][] newGliderArray = new boolean[24][24];
	       boolean[][] incedRes = new boolean[24][24];
	       
	       // these need to be reset for each glider
	       for(int i=0; i<24; i++)
		 for(int j=0; j<24; j++)
		   {
		     gliderArray[i][j] = false;
		     incedRes[i][j] = false;
		   }
	       
	       int x = e.getX(), y = e.getY();
	       int gx, gy, dir;
	       int sum;

	       Graphics g = cvs.img.getGraphics();
	       
	       gx = last_x/16; 
	       gy = last_y/16;
	       
	       // Presumably 0<=gx<4 or 20<=gx<24, &||gy.

	       // Want to maintain outer border (0 or 23) always 0;
	       // so want to center 3x3 glider on 2 or 21.

	       if ((gx<2) || (gx==3))
		 gx=2;
	       else if ((gx>21) || (gx==20))
		 gx=21;

	       if ((gy<2) || (gy==3))
		 gy=2;
	       else if ((gy>21) || (gy==20))
		 gy=21;
	       
	       dir = last_x<x ? (last_y>y? NE:SE) : (last_y>y? NW:SW);

	       // start up the directionally appropriate glider[dir][][]
	       // e.g. for SE from top-left, gx=gy=2;
	       // paste g[SE][0,1,2][0,1,2] to gA[1,2,3][1,2,3]

	       for (int i=0; i<3; i++)
		 for (int j=0; j<3; j++)
		   gliderArray[gx-1+i][gy-1+j] = glider[dir][i][j];

	       // Now the glider update/draw loop:

	     test: while (true)
	       {
		 // No need to draw it the first time --
		 // it's not in the image area yet.
		 
		 for (int i=0; i<23; i++)
		   if (gliderArray[i][0] || gliderArray[i][23]
		       || gliderArray[0][i] || gliderArray[23][i])
		     {
		       break test;
		     }

		 for (int i=0; i<24; i++)
		   for (int j=0; j<24; j++)
		     {
		       // inc sum for all live neighbors
		       sum = 0;
			 
		       if ((i>0) && gliderArray[i-1][j]) sum++;
		       if ((i<23) && gliderArray[i+1][j]) sum++;
		       if ((j>0) && gliderArray[i][j-1]) sum++;
		       if ((j<23) && gliderArray[i][j+1]) sum++;
		       if ((i>0) && (j>0) && gliderArray[i-1][j-1]) sum++;
		       if ((i>0) && (j<23) && gliderArray[i-1][j+1]) sum++;
		       if ((i<23) && (j>0) && gliderArray[i+1][j-1]) sum++;
		       if ((i<23) && (j<23) && gliderArray[i+1][j+1]) sum++;

		       if (!gliderArray[i][j])
			 {
			   if (sum==3)
			     // cell was empty, now alive
			     newGliderArray[i][j] = true;
			   else
			     // cell was empty -- still is.
			     newGliderArray[i][j] = false;
			 }
		       else // (gliderArray[i][j])
			 if ((sum==2)||(sum==3))
			   // cell was alive -- still is
			   newGliderArray[i][j] = true;
			 else
			   // cell was alive, now empty
			   {
			     newGliderArray[i][j] = false;
			     if (!incedRes[i][j])
			       // This is the first update for this pass,
			       // so inc resolution, and make a note of it.
			       {
				 if((e.getModifiers() & e.SHIFT_MASK)==0)
				   { if (res[i][j]<8) res[i][j]++; }
				 else
				   { if (res[i][j]>0) res[i][j]--; }
				 incedRes[i][j] = true;
			       }
			   }

		     } // for
		 
		 // Do all the drawing of f->t and t->f boxes at once:
		 // hoping the gliders will look right
		 for (int i=4; i<20; i++)
		   for (int j=4; j<20; j++)
		     {
		       if (!gliderArray [i][j] && newGliderArray[i][j])
			 // cell was empty, now alive
			 g.drawImage
			   (gliderImgs[dir],
			    16*i,16*j, // between 0+64&255+64
			    cvs);
		       else if (gliderArray[i][j] && !newGliderArray[i][j])
			 // cell was alive, now empty
			 g.drawImage
			   (//imgs[ res[i][j] <= 8 ? res[i][j] : 8],
			    imgs[res[i][j]],
			    // dx1,dy1 -- between 0+64&255+64
			    16*i,16*j,
			    // dx2, dy2 -- between 0+64&255+64
			    16*i+16, 16*j+16,
			    // sx1,sy1 -- between 0&255
			    16*i-64,16*j-64,
			    // sx2, sy2 -- between 0&255
			    16*i+16-64, 16*j+16-64,
			    cvs);
		     }

		 cvs.paint();

		 // Update glider array & go again.
		 for (int i=0; i<24; i++)
		   for (int j=0; j<24; j++)
		     gliderArray[i][j] = newGliderArray[i][j];

		 try { Thread.sleep(delay); }
		 catch (InterruptedException ie) { ; }

	       } //while

	     } //mouseReleased

	 } //MouseAdapter
	 );

      cvs.addKeyListener
	(new KeyAdapter()
	 {
	   public void keyPressed(KeyEvent e)
	     {
	       if ((e.getKeyCode()==10)
		   || (e.getKeyChar()=='\n') 
		   || (e.getKeyChar()==' '))
		 {
		   cvs.img.getGraphics().drawImage(imgs[0], 64,64, cvs);
		   cvs.paint();
		   for (int i=0; i<24; i++)
		     for (int j=0; j<24; j++)
		       res[i][j] = 0;
		 }
	       else if (e.getKeyCode() == KeyEvent.VK_DOWN)
		 {
		   delay +=10; // slower
		 }
	       else if (e.getKeyCode() == KeyEvent.VK_UP)
		 {
		   if (delay>=10) delay-=10;
		 }
	     }
	 }
	 );
    }

  public void show()
    {
      for(int i=0; i<numImgs; i++)
	{
	  this.showStatus("Loading image "+i+" of "+numImgs+"...");
	  
	  try{ mt.waitForID(i);}
	  catch (InterruptedException e)
	    { ; }

	  if (mt.isErrorID(i))
	    {
	      this.showStatus("mt barfed on hand"+i+"; quitting.");
	      return;
	    }
	}
      this.showStatus("Images loaded.");

      cvs.img=cvs.createImage(384,384);
      cvs.img.getGraphics().drawImage(imgs[0], 64,64, cvs);
      cvs.paint();
      super.show();
    }

  public void destroy()
    {
      for (int i=0; i<9; i++)
	imgs[i].flush();
      for (int i=0; i<4; i++)
	gliderImgs[i].flush();
	
    }
      

}