//------------------------------------------------------------------------------
// Rainbow Banner Applet
//
// Copyright 1996, All rights reserved
// You are free to use this java source code at your desire.
// You also understand that by using this code, you are on your own.
// I cannot offer any support if you have problems and no warrantees
// are implied or offered for your use of this source code. 
//
// Applet Parameters:
//    NAME="BANNER"     VALUE="banner"  - The banner string
//    NAME="FONTFACE"   VALUE="Arial"   - The banner font name
//    NAME="FONTSIZE"   VALUE=24        - The point size of the banner font
//    NAME="DELAY"      VALUE=125       - The delay (miliseconds) between each draw
//    NAME="NUMCOLORS"  VALUE=30        - The number of colors to draw with
//  
// Version: 0.9
// Author: Anupriyo Chakravarti (anupriyo@delphi.com)
// Created: 8/17/96
// To do:
//    1. The fontface parameter is not working. I must be doing something wrong.
//    2. Make background color a parameter.
//    3. Get rid of the annoying flickering.
//
// Histroy:
//    08/25/96 Got rid of the flickering. It seems that when 'repaint' is called,
//      it first calls 'update' to clear the window with a gray background before
//      calling 'paint'. This caused the flickering. The trick is to do
//      the painting in the redefined 'update' method rather than in the
//      paint' method.
//------------------------------------------------------------------------------

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

public class banner extends Applet implements Runnable
{
  Font      outFont;          // The font on the banner
  Color[]   arrColors;        // The colors of the rainbow
  char[]    arrChars;         // The characters in the banner
  int       nChars;           // Number of characters in the banner
  int       nColors = 32;     // The number of colors wanted, set through a parameter
  int       iNextColor = 0;   // The start color index to while painting
  int       iDelay = 125;     // The delay (miliseconds) between each paint
  float     fSat = (float)1.00;      // The color Saturation
  float     fBrt = (float)0.85;      // The color Brightness

  boolean   keepRunning = true; // Thread termination flag

  // Class initialization code
  public void init()
  {
    // Load the paramters
    String  str = getParameter("BANNER");
    if (str == null)
      str = "banner";
    String  strFontName = getParameter("FONTFACE");
    if (strFontName == null)
      strFontName = "Arial";
    int nPointSize = 24;
	int nR = 0xFF;
	int nG = 0xFF;
	int nB = 0xFF;
    try
    {
      nPointSize  = Integer.parseInt(getParameter("FONTSIZE"));
      iDelay = Integer.parseInt(getParameter("DELAY"));
      nColors = Integer.parseInt(getParameter("NUMCOLORS"));
	  iNextColor = Integer.parseInt(getParameter("STARTCOLOR"));
	  if ((iNextColor < 0) || (iNextColor >= nColors))
	  {
	    iNextColor = 0;
	  }
	  String strColor = getParameter("BGCOLOR");
	  nR = Integer.parseInt(strColor.substring(0, 2), 16);
	  nG = Integer.parseInt(strColor.substring(2, 4), 16);
	  nB = Integer.parseInt(strColor.substring(4, 6), 16);
	  fSat = (float)Integer.parseInt(getParameter("SATURATION"))/(float)100;
	  fBrt = (float)Integer.parseInt(getParameter("BRIGHTNESS"))/(float)100;
    }
    catch (NumberFormatException e)
    {
    }

    // Fill the color array
    arrColors = new Color[nColors];
    for (int i = 0; i < nColors; i++)
    {
      float hue = (float)i / (float)nColors;
      arrColors[i] = Color.getHSBColor((float)hue, fSat, fBrt);
    }

    // create the output font
    outFont = new Font(strFontName, Font.BOLD, nPointSize);

    // fill the banner characters in the character array
    nChars = str.length();
    arrChars = new char[nChars];
    str.getChars(0, nChars, arrChars, 0);
    
    // set the applet background
    setBackground(new Color(nR, nG, nB));

    // ready to paint
    repaint();
  }
  
  public void update(Graphics g)
  {
    invalidate();
    draw(g);
  }
  
  // This routine handles the painting
  public void draw(Graphics graphic)
  {
     graphic.setFont(outFont);
     
     // x and y hold the left baseline coordinates of the position where
     // the next character will be drawn
     int y = graphic.getFontMetrics(outFont).getMaxAscent();
     int x = 0;
     
     // paint each character in different colors from the color array
     int iColor = iNextColor;
     for (int i = 0; i < nChars; i++)
     {
       graphic.setColor(arrColors[iColor]);
       graphic.drawChars(arrChars, i, 1, x, y);
       x += graphic.getFontMetrics(outFont).charWidth(arrChars[i]);
       iColor = iColor < (nColors-1) ? iColor+1 : 0;
     }
     
     // next time start the painting with this color
     iNextColor = iNextColor < (nColors-1) ? iNextColor+1 : 0;
  }

  // Implements Runnable Interface
  public void run()
  {
    // paint and sleep till we are done
    while (keepRunning)
    {
      repaint();
      try
      {
        Thread.sleep(iDelay);
      }
      catch (InterruptedException e) 
      {
        return;
      }
    }
  }

  public void start() 
  {
    // start a new thread
    keepRunning = true;
    (new Thread(this)).start();
  }

  public void stop()
  {
    // we are done
    keepRunning = false;
  }

  // For running standalone
  public static void main(String[] argv)
  {
    // Create the frame and launch banner
    Frame f = new Frame("bannerFrame");
    f.show();

    banner x = new banner();
    f.add("Center", x);
    x.init();
    x.start();
  }

  // Constructor
  public  banner()
  {
  }

} // end class banner