/**
 * ImageManipulator.java
 *
 * Class for pixel manipulating images -- creating images
 * from pixel data with a memory image source and grabbing
 * pixel's from an existing image with a pixel grabber.
 *
 * @ Authors:
 *
 * @ Wayne Witzel
 * @ University of Utah, Cosmic Ray Physics
 * @
 * @ Copyright 1999, All Rights Reserved
 */
 
import java.awt.image.*;
import java.awt.*;

public class ImageManipulator
{
  MemoryImageSource source;
  MediaTracker tracker;
  Component owner;
  ColorModel colorModel;
  int[] pixels;
  Image image;
  int bgColor;
  int width;
  int height;
  boolean doWrapping = false; // wrap when considering pixels out of bounds

  // create a blank memory image of the given size
  public ImageManipulator(Component owner, int width, int height, int bgColor)
  {
    this.bgColor = bgColor;
    this.owner = owner;
    tracker = new MediaTracker(owner);
    clear(width, height);
    colorModel = new DirectColorModel(32, 255, 255, 255, 255);
  }

  // create a ImageManipulator initialize to the picture of the given image
  public ImageManipulator(Component owner, Image image, int bgColor)
  {
    this.bgColor = bgColor;
    this.owner = owner;
    tracker = new MediaTracker(owner);
    loadImage(image);
  }
  
  // set if you want out of bounds pixels to wrap around or be ignored
  // (default is not to wrap).
  public void setWrapping(boolean doWrapping)
  {
    this.doWrapping = doWrapping;
  }
  
  public boolean isWrapping()
  { return doWrapping; }

  // clear and resize
  public void clear(int width, int height)
  {
    if (pixels == null || (pixels.length < width * height))
      pixels = new int[width * height];
      
    if (this.width != width || this.height != height) {
      this.width = width;
      this.height = height;
      if (colorModel != null)
        source = new MemoryImageSource(width, height, colorModel, pixels, 0, width);
      else 
        source = new MemoryImageSource(width, height, pixels, 0, width);
      source.setAnimated(true);
      if (image != null) {
        tracker.removeImage(image);
        image.flush();
      }
      image = owner.createImage(source);
    }

    for (int i = 0; i < pixels.length; i++)
      pixels[i] = bgColor;
  }

  // clear the entire image with the background color (may be transparent)
  public void clear()
  {
    for (int i = 0; i < pixels.length; i++)
      pixels[i] = bgColor;
  }

  public void clear(Rectangle bounds)
  {
    clear(bounds.x, bounds.y, bounds.width, bounds.height);
  }
  
  // clear a rectangular region with the background color (may be transparent)
  public void clear(int left, int top, int width, int height)
  {
    for (int x = 0; x < width; x++)
      for (int y = 0; y < height; y++)
        setPixel(left + x, top + y, bgColor);
  }
  
  private Point translation = new Point(0, 0);
  public void translate(int x, int y) // move the origin
  {
    translation.x += x;
    translation.y += y;
  }
  
  public void setTranslation(int x, int y)
  {
    translation.x = x;
    translation.y = y;
  }

  public Point getTranslation()
  {
    return translation;
  }
  
  public void setPixel(int x, int y, int value)
  {
    try {
      pixels[getIndex(x, y)] = value;
    }
    catch (IndexOutOfBoundsException e) 
    { /* ignore if out of range */ }
  }
  
  public void setPixel(int index, int value) // see getIndex
  { pixels[index] = value; }

  public int getPixel(int x, int y)
  {
    try {
      return pixels[getIndex(x, y)];
    }
    catch (IndexOutOfBoundsException e) {
      return 0;
    }
  }
  
  public int getPixel(int index) // see getIndex
  { return pixels[index]; }
  
  public int[] getPixels()
  { return pixels; }    
  
  public int getIndex(int x, int y) throws IndexOutOfBoundsException
  {
    x += translation.x;
    y += translation.y;
    if (doWrapping) {
      x %= width;
      y %= height;
      return (y >= 0 ? y : y + height)*width + (x >= 0 ? x : x + width);
    }
    else if (x >= 0 && x < width && y >= 0 && y < height)
      return y*width + x;
    else
      throw new IndexOutOfBoundsException();
  }

  public Image getImage()
  {
    source.newPixels();
    tracker.addImage(image, 0);
    try{tracker.waitForID(0);}
    catch(InterruptedException e) {}
    return image;
  }

  public int getWidth()
  {
    return width;
  }

  public int getHeight()
  {
    return height;
  }
  
  public void loadImage(Image imgSource)
  {
    int width = imgSource.getWidth(owner);
    int height = imgSource.getHeight(owner);

    if (pixels == null || (pixels.length < width * height))
      pixels = new int[width * height];

    if (this.width != width || this.height != height) {
      this.width = width;
      this.height = height;
      source = null;
    }

    PixelGrabber grabber = new PixelGrabber(imgSource, 0, 0, width, height, pixels, 0, width);
    try {
      grabber.grabPixels();
    }
    catch (InterruptedException e)
    { }
    colorModel = grabber.getColorModel();

    if (source == null) {
      if (image != null)
        image.flush();
      source = new MemoryImageSource(width, height, colorModel, pixels, 0, width);
      source.setAnimated(true);
      image = owner.createImage(source);
    }
  }
  
  // invert the image vertically
  public void invertVertical()
  {
    int tmp;
    for (int y = 0; y < height/2; y++)
    {
      for (int x = 0; x < width; x++) {
        tmp = getPixel(x, y);
        setPixel(x, y, getPixel(x, height - y - 1));
        setPixel(x, height - y - 1, tmp);
      }
    }
  }

  // invert the image horizontal
  public void invertHorizontal()
  {
    int tmp;
    for (int x = 0; x < width/2; x++)
    {
      for (int y = 0; y < height; y++) {
        tmp = getPixel(x, y);
        setPixel(x, y, getPixel(width - x - 1, y));
        setPixel(width - x - 1, y, tmp);
      }
    }
  }
  
  public void makeBackgroundTransparent()
  {
    for (int i = 0; i < pixels.length; i++)
      if (pixels[i] == bgColor)
        pixels[i] = 0;
  }
  
  // flush images resources -- this should be done if many
  // ImageManipulator's are created
  public void flush()
  {
    image.flush();
  } 
}