import java.awt.*;
import java.net.*;
import java.util.Random;

public class Scratchpad extends Panel {
  int lastx, lasty;
  public Image offimage;
  Graphics offgraphics;
  Dimension offdimension;
  Color c;
  public int paintmode;
  Random r = new Random();
  int offsetx, offsety;
  
  public void paint(Graphics g) {

    Dimension d = size();
    int dim;

    if (offgraphics == null) {
      if (d.width > d.height)
	dim = round(d.height);
      else
	dim = round(d.width);

      Color bg = getBackground();
      setBackground(new Color(0x0f0f0f));
      offimage = createImage(dim, dim);
      setBackground(bg);

      offgraphics = offimage.getGraphics();
      offdimension = d;
      System.out.println("initialized Scratchpad");
      offgraphics.setColor(c);

    } else if ((offdimension.width != d.width) ||
	     (offdimension.height != d.height)) {
      System.out.println("resized graphics");
      offdimension = d;
      if (d.width > d.height)
	dim = round(d.height);
      else
	dim = round(d.width);
      Image resizedimage = createImage(dim, dim);
      offgraphics = resizedimage.getGraphics();
      offgraphics.drawImage(imageResize(offimage, dim), 0, 0, this);
      offimage = resizedimage;
      offgraphics.setColor(c);
    }
    offsetx = (d.width-offimage.getWidth(this))/2;
    offsety = (d.height-offimage.getHeight(this))/2;
    g.drawImage(offimage, offsetx, offsety, this);
    //    System.out.println(d.width+"x"+d.height);
    // System.out.println(offimage.getWidth(this)+"x"+offimage.getHeight(this));
  }

  public void update(Graphics g){  
    paint(g);
  }

  public void setColor(int in){
    System.out.println("I think the color is: "+in);
    c = new Color(in);
    offgraphics.setColor(c);
  }

  private void drawpoint(int x, int y) {
    if (paintmode == 0)
      offgraphics.drawLine(lastx, lasty, x, y);
    else
      drawchars(x,y);
    repaint();
  }

  private void drawchars(int x, int y) {
    char c = (char)('a' + (r.nextInt() % 26));
    offgraphics.drawString(""+c, x, y);
  }

  public boolean mouseDown(Event e, int x, int y) {
    lastx = x - offsetx;
    lasty = y - offsety;
    drawpoint(x - offsetx, y - offsety);
    return true;
  }

  public boolean mouseDrag(Event e, int x, int y) {
    drawpoint(x - offsetx, y - offsety);
    lastx = x - offsetx;
    lasty = y - offsety;
    return true;
  }

  public void loadImage(URL cb, String newImagename) {
    int dim = offimage.getHeight(this);
    Color bg = getBackground();
    setBackground(new Color(0x0f0f0f));
    offgraphics.clearRect(0,0,dim,dim);
    setBackground(bg);
    Image i=null;
    try{
      Toolkit tk;
      tk = Toolkit.getDefaultToolkit();
      try{
	i = tk.getImage(new URL(newImagename));
	System.out.print ("Loading image: "+newImagename+"...");
      }
      catch (Exception e) {
	System.out.println(e);
	System.out.print("Trying alternate: "+
			 cb.toString()+newImagename+
			 "...");
	i = tk.getImage(new URL(cb,newImagename));
      }
    }
    catch (Exception e){
      System.out.println(e);
    }    
    MediaTracker mt = new MediaTracker(this);
    mt.addImage(i, 0);
    try{
      mt.waitForID(0);
    }
    catch (Exception e){
      System.out.println(e);
    }
    System.out.println("Done.");
    i = imageResize(i, dim);
    offgraphics.drawImage(i, (dim-i.getWidth(this))/2, 
			  (dim-i.getHeight(this))/2, this);
    repaint();
  }

  private int round (int unround) {
    int i = 1;
    while ((unround>>=1) > 0) {
      i <<= 1;
    }
    return i;
  }

  private Image imageResize(Image i, int dim) {
    int w = i.getWidth(this);
    int h = i.getHeight(this);

    if (w > h) {
      h = -1;
      w = dim;
    } else {
      w = -1;
      h = dim;
    }


    i = i.getScaledInstance(w,h,i.SCALE_SMOOTH);
    System.out.println("resized to "+w+" x "+h+" on image "+dim+" x "+dim);

    MediaTracker mt = new MediaTracker(this);

    mt.addImage(i, 7);
    try{
      mt.waitForID(7);
    }
    catch (Exception e){
      System.out.println(e);
    }
    return i;
  }

}