/*
 * Copyright (c) 1998 Kevan Stannard. All Rights Reserved.
 *
 * Permission to use, copy, modify, and distribute this software
 * and its documentation for NON-COMMERCIAL or COMMERCIAL purposes and
 * without fee is hereby granted. 
 * 
 * Please note that this software comes with
 * NO WARRANTY 
 *
 * BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED
 * BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
 * PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
 * TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
 * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 
 * 
 * IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER
 * PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
 * INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
 * THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED
 * BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER
 * OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 */


import java.applet.*;
import java.awt.*;
import java.awt.image.*;
import java.util.*;
import java.net.*;
import java.io.*;

/**
 * JZOOScroller
 *
 * HISTORY
 * 1 Aug 1998 - KS - Created
 * 1 Nov 1998 - KS - Added backgound and target options
 *
 * BUGS
 * Images with a width smaller than speed may not pause.
 */
public class JZOOScroller
extends Applet
implements Runnable
{
    private int MAX_IMAGES = 200;

    Thread thread = null;

    MediaTracker tracker = new MediaTracker(this);

    Vector items = new Vector();
    Image   images[]     = new Image[MAX_IMAGES];
    int     width[]      = new int[MAX_IMAGES];
    int     xPos[]       = new int[MAX_IMAGES];
    boolean imageReady[] = new boolean[MAX_IMAGES];
    URL     links[]      = new URL[MAX_IMAGES];
    String  targets[]    = new String[MAX_IMAGES];

    Image bgImage = null;

    int numImages = 0;
    int centerImage = -1;

    int centerPos = 0;
    int leftCenterPos = 0;
    int rightCenterPos = 0;

    boolean imagesReady = false;

    Image buffer = null;
    Graphics bufferGraphics = null;

    int appletWidth = 0;
    int appletHeight = 0;

    Color bgColor = Color.black;
    Color textColor = Color.green;

    int speed = 1;

    int delay = 5;
    final int frameSleepTime = 10;

    boolean showLinkBorder = false;

    final int LEFT = 0;
    final int RIGHT = 1;
    final int CENTER = 2;
    int textAlign = LEFT;

    String fontName = "arial";
    int fontStyle = Font.PLAIN;
    int fontSize  = 14;

    String itemFileName = null;

    final String SEPARATOR = "#";

    final String TEXT    = "text=";
    final String IMAGE   = "image=";
    final String TARGET  = "target=";
    final String URL     = "url=";

    public void init()
    {
        // init vars

        appletWidth = size().width;
        appletHeight = size().height;

        centerPos = appletWidth / 2;

        // initialise buffer

        buffer = createImage(appletWidth, appletHeight);
        bufferGraphics = buffer.getGraphics();

        // get parameters and add images to array

        String param = getParameter("bgcolor");
        if (param != null)
        {
            if (param.startsWith("#"))
            {
                param = param.substring(1);
            }
            int bgColorValue = Integer.parseInt(param, 16);
            bgColor = new Color(bgColorValue);
        }
        System.out.println("bgColor=" + bgColor);

        param = getParameter("bgimage");
        if (param != null)
        {
            if (param.indexOf(":") > 0)
            {
                try
                {
                    URL bgImageURL = new URL(param);
                    bgImage = getImage(bgImageURL);
                }
                catch (Exception e)
                {
                    System.err.println("error: " + e);
                }
            }
            else
            {
                bgImage = getImage(getCodeBase(), param);
            }

            if (bgImage != null)
            {
                tracker.addImage(bgImage, 0);
                tracker.checkAll(true);
            }
        }
        System.out.println("bgimage=" + bgImage);

        param = getParameter("textcolor");
        if (param != null)
        {
            if (param.startsWith("#"))
            {
                param = param.substring(1);
            }
            int textColorValue = Integer.parseInt(param, 16);
            textColor = new Color(textColorValue);
        }
        System.out.println("textColor=" + textColor);

        param = getParameter("textAlign");
        if (param != null)
        {
            if (param.equalsIgnoreCase("left"))
            {
                textAlign = LEFT;
            }
            else
            {
                if (param.equalsIgnoreCase("center"))
                {
                    textAlign = CENTER;
                }
                else
                {
                    if (param.equalsIgnoreCase("right"))
                    {
                        textAlign = RIGHT;
                    }
                }
            }
        }
        System.out.println("textAlign=" + textAlign);

        param = getParameter("delay");
        if (param != null)
        {
            delay = Integer.parseInt(param);
        }
        System.out.println("delay=" + delay);

        param = getParameter("speed");
        if (param != null)
        {
            speed = Integer.parseInt(param);
        }
        System.out.println("speed=" + speed);

        param = getParameter("fontname");
        if (param != null)
        {
            fontName = param;
        }
        System.out.println("fontName=" + fontName);

        param = getParameter("fontStyle");
        if (param != null)
        {
            if (param.equalsIgnoreCase("plain"))
            {
                fontStyle = Font.PLAIN;
            }
            else
            {
                if (param.equalsIgnoreCase("bold"))
                {
                    fontStyle = Font.BOLD;
                }
                else
                {
                    if (param.equalsIgnoreCase("italic"))
                    {
                        fontStyle = Font.ITALIC;
                    }
                }
            }
        }
        System.out.println("fontStyle=" + fontStyle);

        param = getParameter("fontSize");
        if (param != null)
        {
            fontSize = Integer.parseInt(param);
        }
        System.out.println("fontSize=" + fontSize);

        param = getParameter("itemfile");
        if (param != null)
        {
            itemFileName = param;
        }
        System.out.println("itemFile=" + itemFileName);

        // read the item file

        if (itemFileName != null)
        {
            try
            {
                URL url = new URL(getCodeBase(), itemFileName);
                DataInputStream in = 
                    new DataInputStream(
                    new BufferedInputStream(url.openStream()));

                String inLine = null;
                while (true)
                {
                    inLine = in.readLine();
                    if (inLine == null)
                    {
                        break;
                    }
                    else
                    {
                        items.addElement(inLine);
                    }
                }
                
            }
            catch (Exception e)
            {
                System.out.println(e);
            }
        }
        else
        {
            int i = 0;
            while (true)
            {
                String inLine = getParameter("image" + (i+1));
                if (inLine == null)
                {
                    break;
                }
                items.addElement(inLine);
                i++;
            }
        }

        // construct the images

        int currItem = 0;
        numImages = 0;
        while (currItem < items.size() && numImages<MAX_IMAGES)
        {
            // get the string from the vector

            String itemData = null;
            itemData = (String) items.elementAt(currItem);

            // split on SEPARATOR

            Image  textImage     = null;
            String text          = null;
            Image  image         = null;
            URL    imageURL      = null;
            String target        = null;
            URL    url           = null;

            String token = null;
            String tokenLower = null;
            StringTokenizer tokens = new StringTokenizer(itemData, SEPARATOR);

            while (tokens.hasMoreTokens())
            {
                token = tokens.nextToken();
                token = token.trim();               // remove white space
                tokenLower = token.toLowerCase();   // create a lower case version

                //
                // IMAGE
                //

                if (tokenLower.startsWith(IMAGE))
                {
                    imageURL = null;
                    token = token.substring(IMAGE.length());
                    try
                    {
                        // check if url is a full url ( eg mailto:... or http://... )
                        // ie check for a colon ':'

                        if ( token.indexOf(":") > 0 )
                        {
                            imageURL = new URL(token);
                        }
                        else
                        {
                            imageURL = new URL(getCodeBase(), token);
                        }
                        image = getImage(imageURL);
                    }
                    catch (Exception e)
                    {
                        System.out.println("error: " + e);
                    }

                    //System.out.println("image: " + imageURL);
                    continue;
                }

                //
                // URL
                //

                if (tokenLower.startsWith(URL))
                {
                    token = token.substring(URL.length());
                    try
                    {
                        // check if url is a full url ( eg mailto:... or http://... )
                        // ie check for a colon ':'

                        if ( token.indexOf(":") > 0 )
                        {
                            url = new URL(token);
                        }
                        else
                        {
                            url = new URL(getCodeBase(), token);
                        }
                    }
                    catch (Exception e)
                    {
                        System.out.println("error: " + e);
                    }

                    //System.out.println("url " + url);
                    continue;
                }


                //
                // TARGET
                //

                if (tokenLower.startsWith(TARGET))
                {
                    token = token.substring(TARGET.length());
                    target = token;
                    //System.out.println("target: " + target);
                    continue;
                }

                //
                // TEXT
                //

                if (tokenLower.startsWith(TEXT))
                {
                    token = token.substring(TEXT.length());
                }

                text = token;

                textImage = createImage(appletWidth, appletHeight);

                Graphics textImageGraphics = textImage.getGraphics();

                textImageGraphics.setFont(new Font(fontName, fontStyle, fontSize));
                FontMetrics fm = textImageGraphics.getFontMetrics();

                int textWidth = fm.stringWidth( token );
                int textHeight = fm.getAscent() + fm.getDescent();
                int xBorder = 10;
                int yBorder = 0;
                int textx = 0;
                int texty = fm.getAscent()
                          + (appletHeight - (fm.getAscent() + fm.getDescent()))
                          / 2;

                switch (textAlign)
                {
                    case LEFT:
                    {
                        textx = xBorder;
                        break;
                    }
                    case CENTER: 
                    {
                        textx = (appletWidth - textWidth)/2;
                        break;
                    }
                    case RIGHT:
                    {
                        textx = appletWidth - textWidth - xBorder;
                        break;
                    } 
                    default:
                    {
                        textx = (appletWidth - textWidth)/2;
                    }
                }

                textImageGraphics.setColor(bgColor);
                textImageGraphics.fillRect(0, 0, appletWidth, appletHeight);
                textImageGraphics.setColor(textColor);
                textImageGraphics.drawString(token, textx, texty);

                // Convert all bgcolor pixels to transparent
                // by setting the alpha bits to zero.

                int bgColorValue = bgColor.getRGB();

                int[] pixels = new int[appletWidth * appletHeight];
                try
                {
                    PixelGrabber pg = new PixelGrabber (textImage, 0, 0, appletWidth, appletHeight, pixels, 0, appletWidth);
                    pg.grabPixels();

                    for (int i=0; i<(appletWidth * appletHeight); i++)
                    {
                        if ( pixels[i] == bgColorValue)
                        {
                            // set alpha bits to 0 here (recall that these pixels have the form 0xAARRGGBB)

                            pixels[i] = 0x00FFFFFF;
                        }
                    }
                }
                catch (Exception e)
                { 
                    System.err.println("error: " + e);
                }

                textImage = createImage( new MemoryImageSource(appletWidth, appletHeight, pixels, 0, appletWidth) );

                //System.out.println("text: " + token);
            }

            currItem++;
            if (image == null && textImage == null)
            {
                continue;
            }
        
            if (image != null)
            {
                images[numImages] = image;
                tracker.addImage(image, numImages);
            }
            else
            {
                images[numImages] = textImage;
                tracker.addImage(textImage, numImages);
            }

            links[numImages] = url;
            targets[numImages] = target;

            // ensure image is loading

            tracker.checkID(numImages, true);

            // display

            System.out.println("---");
            System.out.println("image " + numImages);
            System.out.println("  image : " + imageURL);
            System.out.println("  text  : " + text);
            System.out.println("  link  : " + url);
            System.out.println("  target: " + target);

            // next image

            numImages++;
        }

        for (int i=0; i<numImages; i++)
        {
            System.out.println("link " + i + ": " + links[i] );
        }
    }


    public void start()
    {
        if (thread == null)
        {
            thread = new Thread(this);
            thread.start();
        }
    }

    public void stop()
    {
        if (thread != null && thread.isAlive())
        {
            thread.stop();
            thread = null;
        }
    }

    public void update(Graphics g)
    {
        paint(bufferGraphics);
        g.drawImage(buffer,0,0,this);
    }

    public void paint(Graphics g)
    {
       g.setColor(bgColor);
       g.fillRect(0,0,appletWidth, appletHeight);

       if (imagesReady)
       {
           if (bgImage != null)
           {
               g.drawImage(bgImage,0,0,this);
           }

           // only draw the images we have

           for (int i=0; i<numImages; i++)
           {
               g.drawImage(images[i], xPos[i], 0, this);

               if (showLinkBorder && i == centerImage)
               {
                   g.setColor(Color.blue);
                   g.drawRect(xPos[i], 0, width[i]-1, appletHeight-1);
               }
           }
       }
       else
       {
           g.setColor(textColor);
           g.drawString("Loading ...", 20, 20);
       }
    }

    public void run()
    {
        while (true)
        {
            if (imagesReady)
            {
                // is centerImage in center of applet

                leftCenterPos = centerPos - width[centerImage]/2;
                rightCenterPos = leftCenterPos + speed;
                
                if (xPos[centerImage] >= leftCenterPos
                   && xPos[centerImage] < rightCenterPos)
                {
                    try
                    {
                        thread.sleep(delay * 1000);
                    }
                    catch (Exception e)
                    {
                    }

                    centerImage = (centerImage + 1) % numImages;
                }

                // move the scroll

                for (int i=0; i<numImages; i++)
                {
                    xPos[i] -= speed;

                    if (xPos[i] + width[i] < 0)
                    {
                        xPos[i] = Math.max(endOfScroll(), appletWidth);
                    }
                }
            }
            else
            {
                // check if images have loaded

                imagesReady = tracker.checkAll();
                if (imagesReady)
                {
                    centerImage = 0;

                    // initialise positions
                    
                    int x = appletWidth;
                    for (int i=0; i<numImages; i++)
                    {
                        xPos[i] = x;
                        width[i] = images[i].getWidth(this);
                        x += width[i];
                    }
                }
            }

            repaint();

            // sleep a bit

            try
            {
                thread.sleep(frameSleepTime);
            }
            catch (Exception e)
            {
            }
        }
    }

    public boolean mouseDown(Event e, int x, int y)
    {
        // open link to clicked image

        for (int i=0; i<numImages; i++)
        {
            if (x >= xPos[i] && x<= xPos[i] + width[i])
            {
                System.out.println("*** " + i);
                if (links[i] != null)
                {
                    AppletContext context = getAppletContext();
                    if (targets[i] != null)
                    {
                        context.showDocument(links[i], targets[i]);
                    }
                    else
                    {
                        context.showDocument(links[i]);
                    }
                }
                break;
            }
        }

        return true;
    }

    //public boolean mouseEnter(Event e, int x, int y)
    //{
    //}

    //public boolean mouseLeave(Event e, int x, int y)
    //{
    //    return false;
    //}

    public int endOfScroll()
    {
        int maxValue = 0;
        for (int i=0; i<numImages; i++)
        {
            int tempValue = xPos[i] + width[i];
            maxValue = Math.max(tempValue, maxValue);
        }

        return maxValue;
    }
}


/*

                //
                // TEST
                //
 
                int[] pixels = new int[appletWidth * appletHeight];
                PixelGrabber pg = new PixelGrabber(img, 0, 0, appletWidth, appletHeight, pixels, 0, appletWidth);

                try
                {
                    pg.getPixels();
                }
                catch (Exception e)
                {
                    System.out.println("error: " + e);
                }


                for (int i=0; i<(appletWidth * appletHeight); i++ )
                {
                    if (pixels[i] > 0) System.out.println(pixels[i]);
                }

                //img = createImage( new MemoryImageSource(appletWidth, appletHeight, pixels, 0, appletWidth) );


*/