/**
 
      a mix of old and new java...
      
      originally written ages ago in java 1.0,
      recently spiffed up using some swing.
 
      runs OK using netscape under X-window, which is probably 
      as narrow a channel is it would need to pass through.
       
      [ miles zarathustra    www.aranyaka.org ]
*/ 
 
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;


class Util {
  /** 
      representation of n (the 1st parameter) 
      to width w (2nd parameter)
      padded on the left with 0

  */
  public static String zeroPadLeft(int n, int w) { 
    return padLeft(""+n, w, '0'); 
  }

  /**
        pad string str to the left, to width w, with charcter c.
  */
  public static String padLeft(String str, int w, char c) {
    if (str.length() >= w) return str;
    StringBuffer sb=new StringBuffer();
    for (int i = w - str.length(); i > 0; --i) sb.append(c);
    sb.append(str);
    return new String(sb);
  }
}


class Shade extends Canvas {
  float h=0.5f, s=0.5f, b=0.5f; 
  Font font;

  Shade() {
    font=new Font("TimesRoman",Font.BOLD,20);
  }

  void
  setShade(float H, float S, float B) {
    setBackground(
      new Color(Color.HSBtoRGB(
        h=Math.min(1.0f,H/1000.0f),
        s=Math.min(1.0f,S/1000.0f),
        b=Math.min(1.0f,B/1000.0f)
      ))
    );
    repaint();
  }
  public void
  paint(Graphics g) {
    Color bg=getBackground();
    setForeground(new Color(~bg.getRGB()));

    g.setFont(font);
  }
}


public class Hue extends Applet {
  Scrollbar hue, sat, bri;
  Shade shade;
  TextField hueText, satText, briText, colorText;
  

  static TextField newTextField() {
    TextField R = new TextField(8);
    R.setEditable(false);
    R.setBackground(Color.white);
    return R;
  }
  
  public Hue() {
    setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
    Panel textPanel = new Panel(new FlowLayout()), 
          huePanel = new Panel(new BorderLayout());

    textPanel.add(new Label("color:"));
    textPanel.add(colorText = newTextField());
    textPanel.add(new Label("  H="));
    textPanel.add(hueText = newTextField());
    textPanel.add(new Label("; S="));
    textPanel.add(satText = newTextField());
    textPanel.add(new Label("; B="));
    textPanel.add(briText = newTextField());
    
    huePanel.add("Center",shade=new Shade());
    int maxVal = 1010; // I forget why the extra 10, 
                       // but there must have been a good reason.
    huePanel.add("West",bri=new Scrollbar(Scrollbar.VERTICAL,
      (int)(maxVal * shade.b),10,0,maxVal));
    huePanel.add("North",hue=new Scrollbar(Scrollbar.HORIZONTAL,
      (int)(maxVal * shade.h),10,0,maxVal));
    huePanel.add("East",sat=new Scrollbar(Scrollbar.VERTICAL,
      (int)(maxVal * shade.s),10,0,maxVal));

    add(textPanel); add(huePanel);
    setColor();
    setTextFields();
  }

  public void init() { }

  void
  setColor() {
    float h=hue.getValue(),s=sat.getValue(),b=bri.getValue();
    shade.setShade(h,s,b);
  }
  void setTextFields() {
    hueText.setText(shade.h+"");
    satText.setText(shade.s+"");
    briText.setText(shade.b+"");
    colorText.setText(
      Util.padLeft(
	Integer.toString(0xffffff & shade.getBackground().getRGB(),16),
        6, '0'));
  }

  public boolean
  handleEvent(Event evt) {
    if (evt.target==hue || evt.target==sat || evt.target==bri) {
      setColor();
      setTextFields();
      return true;
    }
    return false;
  }

  
  public static void main(String[] args) {
    final Frame f=new Frame("hue");
    f.add(new Hue(),BorderLayout.CENTER);
    f.pack();
    f.setSize(600,600);
    //f.addWindowListener(new WindowAdapter() {
    class WindowCloser extends WindowAdapter {
      public void windowClosing(WindowEvent evt) {
        f.dispose();
	System.exit(0);
      }
    }
    f.addWindowListener(new WindowCloser());
    f.setVisible(true);
  }
}