/**
 * NavigatorTicker --Copyright Ahmed Abdelhady 1996 <b>ahady@idsc.gov.eg<b> <br>
 *  A live Hypertext java applets.
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation without fee for NON-COMMERCIAL purposes is hereby granted
 * provided that this notice with a reference to the original source and 
 * the author appears in all copies or derivatives of this software.
 *
 * All other rights are resevred.
 *
 * THE AUTHOR MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
 * THIS SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
 * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHOR SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY ANYBODY AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
 */

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


public class NavigatorTicker extends java.applet.Applet implements Runnable {

  /** index for the active message */
  public int messageIndex=0;

  /** TOtal no of messages */
  public int messageCount=1;
  
 /** The message to be displayed. */
  public String message;

 /** The messages Vector. */
  public Vector msgs=new Vector(); 

  /** The Font to be displayed. */
  public Font messageF;
 
  /** x-position of message. */
  public int messageX;

  /** y-position of message. */
  public int messageY;

  /** Length of the Active message. */
  public int messageW = 0;

  /** Messages Lengths Vector */
  public Vector msgsW= new Vector(); 

  /** URL to switch to */
  public URL url_ = null;

  /** Target URLs Vector */
  public Vector msgsURL=new Vector();

  /** How far to skip across the screen. */
  int speed;

  /** The animating thread. */
  public Thread t = null;

  /** State of the applet. */
  public boolean active = false;

  /** The Text-color. */
  public Color txtCo;

 /** The Link-color. */
  public Color linkCo;
 
 /** The backgroundcolor. */
  public Color bgCo;

  
  /** The Size used to calc the Font. */
  public Dimension lastS = new Dimension(1,1);

  /** The offscreen image. */
  Image im = null;

  /** The offscreen Graphics context */
  Graphics gr = null;

 /* A flag that indicate mouse movement over the Applet  */
boolean display_URL=false;

 /* Mouse x Position  */
int mouseX=0;


  /**
   * Initialize: Read Parameters
   *  
   */
  public void init () {
 
String at;
   
    messageCount=((at = getParameter("count")) == null) ? 0 : (Integer.valueOf(at).intValue());
       for (int i = 0; i <messageCount; i++) {
		at=getParameter("msg"+i);
		StringTokenizer str= new StringTokenizer(at,"\\"); // to separate the msg & Url
		msgs.addElement(new String(str.nextToken() ) );
		 msgsURL.addElement(new String(str.nextToken() ) ); // URLs as Strings
    }    

   
    speed = ((at = getParameter("speed")) == null) ? 10 : (Integer.valueOf(at).intValue());


    // get the colors
    txtCo = readColor(getParameter("txtco"), bgCo);
    linkCo = readColor(getParameter("linkco"), bgCo); 
    bgCo = readColor(getParameter("bgco"), getBackground());

  }

  /** Parameter Info. */
  public String[][] getParameterInfo() {
    String[][] info = {
      {"count",    "int",  "Toatal Number of Messages" },
      {"msg%N",    "String",  "Message to display with optional URL delimited by \\"},
      {"speed",  "int",     "animation speed in pixels (10)"},
      {"txtco",  "int[3]",  "RGB-Color of Message (black/blue)"},
      {"bgco",   "int[3]",  "RGB-Color of background (getBackground)"},
      
    };
    return info;
  }

  /** Applet Info. */
  public String getAppletInfo() {
    return "HadyTicker.java, V b1, 1/4/96 by Ahmed Abdel-Hady extending the original ticker by Thomas Wendt, http://www.uni-kassel.de/fb16/ipm/mt/staff/thwendte.html";
  }    

  /**
    Convert a "," delimited String with RGB-Values to Color
    Uses aDefault, if no or not enough RGB-Values.
   */
  public Color readColor(String aColor, Color aDefault) {
    if (aColor == null) { return aDefault; }

    int r, g, b;
    StringTokenizer st = new StringTokenizer(aColor, ",");
    
    try {
      r = Integer.valueOf(st.nextToken()).intValue();
      g = Integer.valueOf(st.nextToken()).intValue();
      b = Integer.valueOf(st.nextToken()).intValue();
      return new Color(r,g,b);
    }
    catch (Exception e) { return aDefault; }
  }

  /**
   * Create the image Parameters.
   * Called, if just created or size has changed
   */

  public void createParams() {
    // Init some constants
    int w = size().width;
    int h = size().height;
    lastS.width = w;
    lastS.height = h;

    // dispose old buffer etc.
    if (gr != null) { gr.finalize(); }
    if (im != null) { im = null; }
    // Calc the font and positions. Message must fit applets area.
    int refH = 14;
    Font tf = new Font("TimesRoman", Font.BOLD, refH);
    setFont(tf);
    FontMetrics tfm = getFontMetrics(tf);
    int fh = tfm.getHeight();
    fh = refH*(h-10)/fh;
    messageF = new Font("TimesRoman", Font.BOLD, fh);
    FontMetrics fm = getFontMetrics(messageF);
    fh = fm.getHeight();
    messageX = w;
    messageY = ((h-fh) >> 1)+fm.getAscent();
    for(int i=0; i<messageCount;i++){
        msgsW.addElement( new Integer(fm.stringWidth((String) msgs.elementAt(i)) )  );
        messageW+=fm.stringWidth((String) msgs.elementAt(i)) ;
	}
    im = createImage(w, h);
    gr = im.getGraphics();
  }

  /** 
      Painting the applet calls the overriding update to elimentate flicker 
    */
  public void paint(Graphics g) { update(g); }

  /** Show the stuff */
  public synchronized void update(Graphics g) {
        // Recalc params, if something has changed
    if ((size().height != lastS.height) || (size().width != lastS.width)) { createParams(); }

    // fill area with bgcolor
    gr.setColor(bgCo);
    gr.fillRect(0,0,lastS.width,lastS.height);

    // if url is given, let it look like a link
   // if (url_ != null) {
      //gr.setColor(Color.blue);
      gr.drawRect(0,0,lastS.width-1,lastS.height-1);
      gr.drawRect(1,1,lastS.width-3,lastS.height-3);
      gr.setColor(bgCo);
      gr.draw3DRect(2,2,lastS.width-5, lastS.height-5, true);
      gr.draw3DRect(3,3,lastS.width-7, lastS.height-7, true);
      gr.clipRect(5,4,lastS.width-10, lastS.height-8);
   // }

 // show status .. track mouse position..
    if(display_URL) {
      int currX=0,x=mouseX;
      
      if( x > messageX ){ // clicking Nonempty area
         x-=messageX;  // compute displacement relative to start of the message
         for(int i =0; i< messageCount; i++){
             currX+=((Integer) msgsW.elementAt(i)).intValue();
	  // compare to acumulated widths to get clicked message index.
             if ( x < currX ) { messageIndex=i; break;}
         }  // end for
      } // end if (mouse...

    showStatus((String)	msgsURL.elementAt(messageIndex) );
    }	

    // draw the text
    gr.setColor(txtCo);
    gr.setFont(messageF);

    int disp=0;
    for(int i=0;i<messageCount;i++){
     if(i==messageIndex && display_URL) gr.setColor(linkCo);
     else gr.setColor(txtCo);
    gr.drawString((String) msgs.elementAt(i), messageX+disp, messageY); //////////////
    disp+=((Integer) msgsW.elementAt(i)).intValue();
    }
    // finally show all together on the screen
    g.drawImage(im,0,0,this);
  }
  /** calc next position of message and call repaint */
  public synchronized void nextPos() {
      // decrement position
      messageX -= speed;
      // and stay in the bounds
      if ((messageX + messageW) < 0) {
	messageX = lastS.width;
      }
      // indirectly call update
      repaint();
  }

  /** Run the loop. This method is called by class Thread. */
  public void run() {
        // others might be more important
    Thread.currentThread().setPriority(Thread.MIN_PRIORITY);
    while (active) {
      // do the job
      nextPos();
      // pause
      try {Thread.sleep(100);}
      catch (InterruptedException e){ }
    }
  }

  /** Start the applet by forking an animation thread. */
  public void start() {
    if (!active) {
      t = new Thread(this);
      active = true;
      t.start();
    }
  }

  /** Stop the applet. The thread will exit because run() exits. */
  public void stop() {
    active = false;
    t = null; // give GC a chance.
  }

  /** Switch to url, if url is given. */
  public boolean mouseUp(Event evt, int x, int Y) {

 try { url_ = new URL((String)msgsURL.elementAt(messageIndex)); }
catch (Exception e) { url_ = null; }
 if ( url_ != null) { getAppletContext().showDocument( url_); } // might not work with some early browsers
    return true;
  }

public boolean mouseEnter(Event evt, int x, int Y) {

 display_URL = true;
 return true;
  }

public boolean mouseExit(Event evt, int x, int Y) {

 display_URL = false;
 return true;
  }

public boolean mouseMove(Event evt, int x, int Y) {
   mouseX=x;

  
return true;
 } // end handler fn

} // End Applet class