/*
 * @(#)ImageChanger.java      
 *
 * Copyright (c) 1996,1997 NAKAGAWA Masami
 *
 * Permission to use, copy, modify, and distribute this software
 * for NON-COMMERCIAL purpose and without fee is hereby granted. 
 */

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

/** A class of GIF(JPEG) image changer to decorate a Web page
 * @author	NAKAGAWA Masami
 * @version	2.01, 9 Aug 1997
 */
public class ImageChanger extends Applet implements Runnable {
	final int FADEMAX = 16;
	final int FADEWID = 64;
	final int EFFECTNUM = 20;
	final int PADX = 10;
	final int PADY = 10;
	final int NONE = 0;
	final int SCROLLUP = 1;
	final int SCROLLDOWN = 2;
	final int SCROLLRIGHT = 3;
	final int SCROLLLEFT = 4;
	final int TEARVERTICAL = 5;
	final int TEARHORIZONTAL = 6;
	final int OPEN = 7;
	final int CLOSE = 8;
	final int FADE = 9;
	final int MOSAIC = 10;
	final int TEARUP = 11;
	final int TEARDOWN = 12;
	final int TEARRIGHT = 13;
	final int TEARLEFT = 14;
	final int SLIDEUP = 15;
	final int SLIDEDOWN = 16;
	final int SLIDERIGHT = 17;
	final int SLIDELEFT = 18;
	final int SHRINKVERTICAL = 19;
	final int SHRINKHORIZONTAL = 20;
	
	Dimension mySize;
	MediaTracker tracker;
	Image[] images;
	String[] imageFile;
	int[] change;
	int[] time;
	String imageDir = ".";
	int imageNum;
	int defaultChange;
	int defaultTime = 5000;
	Color fadeColor = Color.black;
	Color bgColor = Color.black;
	Color fontColor = Color.white;
	Color fontShadowColor;
	Color fontLineColor;
	Color fontBackColor;
	int scrollSpeed = 6;
	int changeSpeed = 3;
	int fadeTime = 80;
	Image[] fadeImage = new Image[FADEMAX];
	Image mosaicImage;
	Thread kicker;
	int current;
	Graphics offScreen;
	Graphics onScreen;
	Image offImage;
	boolean drawWhileLoading = true;
	int mosaicWidth = 16;
	int mosaicHeight = 16;
	int mosaicSpeed = 4;
	Random rand;
	URL[] url;
	boolean randomOrder = false;
	boolean randomEffect = false;
	boolean cursorIn = false;
	boolean autoLink = false;
	boolean linked = false;
	AppletContext context;
	String[] title;
	Point[] titlePos;
	Rectangle[] titleBackArea;
	Font font;
	FontMetrics metrics;
	String target;
	String frame;

	public void init() {
		setBackground(bgColor);
		String s;
		s = getParameter("imageDir");
		if (s != null) imageDir = s;
		s = getParameter("change");
		if (s != null) defaultChange = Integer.parseInt(s);
		s = getParameter("time");
		if (s != null) defaultTime = Integer.parseInt(s);
		s = getParameter("fadeColor");
		if (s != null) fadeColor = new Color(Integer.parseInt(s, 16));
		s = getParameter("bgColor");
		if (s != null) bgColor = new Color(Integer.parseInt(s, 16));
		s = getParameter("fontColor");
		if (s != null) fontColor = new Color(Integer.parseInt(s, 16));
		s = getParameter("fontLineColor");
		if (s != null) fontLineColor = new Color(Integer.parseInt(s, 16));
		s = getParameter("fontShadowColor");
		if (s != null) fontShadowColor = new Color(Integer.parseInt(s, 16));
		s = getParameter("fontBackColor");
		if (s != null) fontBackColor = new Color(Integer.parseInt(s, 16));
		s = getParameter("scrollSpeed");
		if (s != null) scrollSpeed = Integer.parseInt(s);
		s = getParameter("changeSpeed");
		if (s != null) changeSpeed = Integer.parseInt(s);
		s = getParameter("fadeTime");
		if (s != null) fadeTime = Integer.parseInt(s) / FADEMAX;
		s = getParameter("drawWhileLoading");
		if (s != null) drawWhileLoading = Boolean.valueOf(s).booleanValue();
 		s = getParameter("mosaicWidth");
		if (s != null) mosaicWidth = Integer.parseInt(s);
  		s = getParameter("mosaicHeight");
		if (s != null) mosaicHeight = Integer.parseInt(s);
  		s = getParameter("mosaicSpeed");
		if (s != null) mosaicSpeed = Integer.parseInt(s);
 		s = getParameter("randomOrder");
		if (s != null) randomOrder = Boolean.valueOf(s).booleanValue();
		s = getParameter("randomEffect");
		if (s != null) randomEffect = Boolean.valueOf(s).booleanValue();
		s = getParameter("fontSize");
		font = new Font("Dialog", Font.PLAIN, (s == null)?12:Integer.parseInt(s));
		s = getParameter("target");
		if (s != null) target = s;
		s = getParameter("frame");
		if (s != null) frame = s;
		s = getParameter("autoLink");
		if (s != null) autoLink = Boolean .valueOf(s).booleanValue();

		mySize = size();
		rand = new Random();
		context = getAppletContext();

		initImages();
		initTitles();
    }
	
	private void initImages() {
		String s = getParameter("images");
		StringTokenizer t1 = new StringTokenizer(s, ",");
		imageNum = t1.countTokens();
		images = new Image[imageNum];
		imageFile = new String[imageNum];
		change = new int[imageNum];
		time = new int[imageNum];
		url = new URL[imageNum];
		int count = 0;
		while (t1.hasMoreTokens()) {
			s = t1.nextToken();
			StringTokenizer t2 = new StringTokenizer(s, "|");
			imageFile[count] = t2.nextToken().trim();
			change[count] = defaultChange;
			if (t2.hasMoreTokens()) {
				s = t2.nextToken().trim();
				try {
					if (s != null && !s.equals("-")) change[count] = Integer.parseInt(s);
				} catch (NumberFormatException e) {
				}
			}
			time[count] = defaultTime;
			if (t2.hasMoreTokens()) {
				s = t2.nextToken().trim();
				try {
					if (s != null && !s.equals("-")) time[count] = Integer.parseInt(s);
				} catch (NumberFormatException e) {
				}
			}
			if (t2.hasMoreTokens()) {
				s = t2.nextToken().trim();
				try {
					if (s != null && !s.equals("-")) url[count] = new URL(s);
				} catch (MalformedURLException e) {
					try {
						url[count] = new URL(getDocumentBase(), s);
					} catch (MalformedURLException ex) {
					}
				}
			}
			count++;
		}
	}
	
	private void initTitles() {
	    int count = 0;
	    title = new String[imageNum];
	    titlePos = new Point[imageNum];
	    if (fontBackColor != null) {
    	    titleBackArea = new Rectangle[imageNum];
    	}
	    metrics = getFontMetrics(font);
	    String s = getParameter("titles");
	    if (s != null) {
	        StringTokenizer st1 = new StringTokenizer(s, ",");
	        while (st1.hasMoreTokens()) {
	            String t = st1.nextToken();
	            if (!t.equals("-")) {
    	            StringTokenizer st2 = new StringTokenizer(t, "|");
    	            if (st2.hasMoreTokens()) {
    	                title[count] = st2.nextToken();
    	                int x = PADX;
    	                int y = PADY + metrics.getAscent();
    	                int width = metrics.stringWidth(title[count]);
    	                int height = metrics.getAscent();
    	                if (st2.hasMoreTokens()) {
    	                    String u = st2.nextToken();
            			    if ("n".equals(u)) {
        			            x = (mySize.width - width) / 2;
        			            y = PADY + height;
            			    } else if ("ne".equals(u)) {
        			            x = mySize.width - PADX - width;
        			            y = PADY + height;
            			    } else if ("c".equals(u)) {
        			            x = (mySize.width - width) / 2;
        			            y = (mySize.height + height) / 2;
            			    } else if ("sw".equals(u)) {
        			            x = PADX;
        			            y = mySize.height - PADY;
            			    } else if ("s".equals(u)) {
        			            x = (mySize.width - width) / 2;
        			            y = mySize.height - PADY;
            			    } else if ("se".equals(u)) {
        			            x = mySize.width - PADX - width;
        			            y = mySize.height - PADY;
            			    }
    	                }
    	                titlePos[count] = new Point(x, y);
    	                if (fontBackColor != null) {
        	                titleBackArea[count] = new Rectangle(x - 5, y - height - 5,
        	                    width + 10, height + 10);
        	            }
        	        }
	            }
	            count++;
	        }
	    }
	}
	
	public void start() {
		for (int i = 0; i < images.length; i++) {
			try {
				URL imgUrl = new URL(imageFile[i]);
				images[i] = getImage(imgUrl);
			} catch (MalformedURLException e) {
				images[i] = getImage(getDocumentBase(), imageDir + "/" + imageFile[i]);
			}
		}
		offImage = createImage(mySize.width, mySize.height);
		offScreen = offImage.getGraphics();
		onScreen = getGraphics();
		mosaicImage = createImage(mySize.width, mySize.height);
		tracker = new MediaTracker(this);
		for (int i = 0; i < images.length; i++) {
			tracker.addImage(images[i], i);
		}
		makeFadeImages();
		if (kicker == null) {
			kicker = new Thread(this);
			kicker.start();
		}
	}

	void makeFadeImages() {
		int[][] pix = new int[FADEMAX][FADEWID*FADEWID];
		for (int i = 0; i < FADEMAX; i++) {
			for (int y = 0; y < FADEWID; y++) {
				for (int x = 0; x < FADEWID; x++) {
					pix[i][x+y*FADEWID] = (0xff*(i+1)/FADEMAX)<<24 | (fadeColor.getRGB() & 0x00ffffff);
				}
			}
			MemoryImageSource mis = new MemoryImageSource(FADEWID, FADEWID, pix[i], 0, FADEWID);
			fadeImage[i] = createImage(mis);
		}
	}

	public void stop() {
		if (kicker != null) {
			kicker.stop();
		}
		kicker = null;
	}

	public void paint(Graphics g) {
		g.drawImage(offImage, 0, 0, null);
	}

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

	void drawMessage(String message) {
		offScreen.setColor(bgColor);
		offScreen.fillRect(0, 0, mySize.width, mySize.height);
		offScreen.setColor(Color.cyan);
		offScreen.drawString(message, 10, 20);
	}

	void scrollImage(Image fore, Image back, int dx, int dy) {
		int fx = (mySize.width - fore.getWidth(null)) / 2;
		int fy = (mySize.height - fore.getHeight(null)) / 2;
		int bx = (mySize.width - back.getWidth(null)) / 2;
		int by = (mySize.height - back.getHeight(null)) / 2;
		int width = fore.getWidth(null);
		int height = fore.getHeight(null);
		while (fx + width > 0 && fx < mySize.width
				&& fy + height > 0 && fy < mySize.height) {
			fx += dx;
			fy += dy;
			offScreen.setColor(bgColor);
			offScreen.fillRect(0, 0, mySize.width, mySize.height);
			offScreen.drawImage(back, bx, by, null);
			offScreen.drawImage(fore, fx, fy, null);
			onScreen.drawImage(offImage, 0, 0, null);
			try {
				Thread.currentThread().sleep(50);
			} catch (InterruptedException e) {
			}
		}
	}

	void slideImage(Image back, Image fore, int dx, int dy) {
	    int fx = 0;
	    int fy = 0;
		int width = fore.getWidth(null);
		int height = fore.getHeight(null);
		int bx = (mySize.width - back.getWidth(null)) / 2;
		int by = (mySize.height - back.getHeight(null)) / 2;
		int endx = (mySize.width - width) / 2;
		int endy = (mySize.height - height) / 2;
		if (dx != 0) {
    	    fx = (dx > 0)?-width:mySize.width;
    	    fy = endy;
    	} else {
    	    fy = (dy > 0)?-height:mySize.height;
    	    fx = endx;
    	}
		while (true) {
		    if (dx != 0) {
    			fx += dx;
    			if ((dx > 0 && fx > endx) || (dx < 0 && fx < endx)) break;
    		} else {
    			fy += dy;
    			if ((dy > 0 && fy > endy) || (dy < 0 && fy < endy)) break;
    		}
			offScreen.setColor(bgColor);
			offScreen.fillRect(0, 0, mySize.width, mySize.height);
			offScreen.drawImage(back, bx, by, null);
			offScreen.drawImage(fore, fx, fy, null);
			onScreen.drawImage(offImage, 0, 0, null);
			try {
				Thread.currentThread().sleep(50);
			} catch (InterruptedException e) {
			}
		}
	}

	void tearImage(Image image, int dx, int dy) {
		int w = 0;
		int h = 0;
		int	x1 = (mySize.width - image.getWidth(null)) / 2;
		int	y1 = (mySize.height - image.getHeight(null)) / 2;
		int x2 = x1+image.getWidth(null);
		int y2 = y1+image.getHeight(null);
		while (w < image.getWidth(null) && h < image.getHeight(null)) {
			if (dx > 0) {
				w += dx;
				offScreen.clipRect(x1, 0, w, mySize.height);
			} else if (dy > 0) {
				h += dy;
				offScreen.clipRect(0, y1, mySize.width, h);
			} else if (dx < 0) {
				x2 += dx;
				w -= dx;
				offScreen.clipRect(x2, 0, w, mySize.height);
			} else if (dy < 0) {
				y2 += dy;
				h -= dy;
				offScreen.clipRect(0, y2, mySize.width, h);
			}
			offScreen.drawImage(image, x1, y1, null);
			onScreen.drawImage(offImage, 0, 0, null);
			try {
				Thread.currentThread().sleep(50);
			} catch (InterruptedException e) {
			}
			offScreen.dispose();
			offScreen = offImage.getGraphics();
		}
	}

	void tearOpenImage(Image image, int dx, int dy) {
		int x = mySize.width / 2;
		int y = mySize.height / 2;
		int w = 0;
		int h = 0;
		int nx = (mySize.width - image.getWidth(null)) / 2;
		int ny = (mySize.height - image.getHeight(null)) / 2;
		while (x > nx && y > ny) {
			if (dx > 0) {
				x -= dx;
				w += dx * 2;
				offScreen.clipRect(x, 0, w, mySize.height);
			} else if (dy > 0) {
				y -= dy;
				h += dy * 2;
				offScreen.clipRect(0, y, mySize.width, h);
			}
			offScreen.drawImage(image, nx, ny, null);
			onScreen.drawImage(offImage, 0, 0, null);
			try {
				Thread.currentThread().sleep(50);
			} catch (InterruptedException e) {
			}
			offScreen.dispose();
			offScreen = offImage.getGraphics();
		}