/* PixelGrabber.java -- Java class for providing image data 
   Copyright (C) 1999 Free Software Foundation, Inc.

This file is part of the non-peer AWT libraries of GNU Classpath.

This library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published 
by the Free Software Foundation, either version 2 of the License, or
(at your option) any later verion.

This library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Library General Public License for more details.

You should have received a copy of the GNU Library General Public License
along with this library; if not, write to the Free Software Foundation
Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307 USA. */


package java.awt.image;

import java.awt.Image;
import java.util.Hashtable;

/**
   PixelGrabber is an ImageConsumer designed to extract a rectangular region of pixels
   from an Image
 */
public class PixelGrabber implements ImageConsumer 
{
    int x, y, width, height, status, scansize, offset;
    ColorModel model = ColorModel.getRGBdefault();
    //int hints;
    //Hashtable props;
    int pixel_bufferi[];
    byte pixel_bufferb[];
    boolean grabbing;
    ImageProducer ip;

    /**
     * Create a PixelGrabber used to grab pixels from the specified Image 
     * in the specified rectangle
     *
     * @param img the Image to grab pixels from
     * @param x the x coordinate of the rectangle
     * @param y the y coordinate of the rectangle
     * @param w the width of the rectangle
     * @param h the height of the rectangle
     * @param pixels the array of pixel values
     * @param offset the index of the first pixels in the <code>pixels</code> array
     * @param scansize the width to use in extracting pixels from the <code>pixels</code> array
     */
    public PixelGrabber(Image img, int x, int y, int w, int h,
			int pix[], int off, int scansize)
    {
	this( img.getSource(), x, y, w, h, pix, off, scansize );
    }

    /**
     * Create a PixelGrabber used to grab pixels from the specified ImageProducer
     * in the specified rectangle
     *
     * @param ip the ImageProducer to grab pixels from
     * @param x the x coordinate of the rectangle
     * @param y the y coordinate of the rectangle
     * @param w the width of the rectangle
     * @param h the height of the rectangle
     * @param pixels the array of pixel values
     * @param offset the index of the first pixels in the <code>pixels</code> array
     * @param scansize the width to use in extracting pixels from the <code>pixels</code> array
     */
    public PixelGrabber(ImageProducer ip, int x, int y, int w, int h,
			int pix[], int off, int scansize)
    {
	this.ip = ip;
	this.x = x;
	this.y = y;
	this.width = w;
	this.height = h;
	this.pixel_bufferi = pix;
	this.offset = off;
	this.scansize = scansize;
	pixel_bufferb = new byte[pix.length * 4];
    }


    /**
     * Create a PixelGrabber used to grab pixels from the specified Image 
     * in the specified rectangle
     *
     * @param img the Image to grab pixels from
     * @param x the x coordinate of the rectangle
     * @param y the y coordinate of the rectangle
     * @param w the width of the rectangle
     * @param h the height of the rectangle
     * @param forceRGB true to force conversion to RGB
     */
    public PixelGrabber(Image img,
			int x, int y,
			int w, int h,
			boolean forceRGB)
    {
	//FIXME
    }

    /**
       Start Grabbing Pixels
     */
    public synchronized void startGrabbing()
    {
	if ( grabbing == false )
	    {
		grabbing = true;
		ip.startProduction( this );
	    }
    }

    /**
       Abort the grabbing of pixels
     */
    public synchronized void abortGrabbing()
    {
	if ( grabbing == true )
	    {
		grabbing = false;
		ip.removeConsumer( this );
	    }
    }

    /**
       Grab the Pixels.

       @return true if successful

       @throws InterruptedExcpetion if interrupted by another thread.
     */
    public boolean grabPixels() throws InterruptedException
    {
	startGrabbing();
	while ( (status != ImageObserver.ALLBITS ) ||
		(status != ImageObserver.ERROR ) ||
		(status != ImageObserver.ABORT ) );

	if( status == ImageObserver.ALLBITS )
	    return true;
	else
	    return false;
    }

    /**
       Grab the Pixels and abort if it takes too long

       @return true if successful

       @throws InterruptedExcpetion if interrupted by another thread.
               or time runs out
     */
    public synchronized boolean grabPixels(long ms) throws InterruptedException
    {
	long start = System.currentTimeMillis();
	startGrabbing();
	while ( (status != ImageObserver.ALLBITS ) ||
		(status != ImageObserver.ERROR ) ||
		(status != ImageObserver.ABORT ) )
	    {
		if( (System.currentTimeMillis() - start ) >= ms )
		    {
			abortGrabbing();
			throw new InterruptedException();
		    }
	    }

	if( status == ImageObserver.ALLBITS )
	    return true;
	else
	    return false;
	
    }

    /**
       Get the status of the pixel grabbing representing by ImageObserver flags

       @return the status
    */
    public synchronized int getStatus()
    {
	return status;
    }

    /**
       Return width of pixel region

       @return width of region
    */
    public synchronized int getWidth()
    {
	return width;
    }

    /**
       Return height of pixel region
       
       @return height of region
    */
    public synchronized int getHeight()
    {
	return height;
    }

    /**
       Returns the grabbed pixel buffer 

       @return a byte or int array
    */
    public synchronized Object getPixels()
    {
	if( pixel_bufferi != null )
	    return pixel_bufferi;
	return pixel_bufferb;
    }

    /**
       Get the ColorModel of the image
       
       @return the ColorModel
    */
    public synchronized ColorModel getColorModel()
    {
	return model;
    }

    /**
     * An <code>ImageProducer</code> indicates the size of the image
     * being produced using this method.
     * 
     * @param width the width of the image
     * @param height the height of the image 
     */
    public  void setDimensions(int width, int height)
    {
    }

    /**
     * An <code>ImageProducer</code> can set a list of properties
     * associated with this image by using this method.
     *
     * @param props the list of properties associated with this image 
     */
    public  void setProperties(Hashtable props)
    {
	//this.props = props; //FIXME - DO WE NEED THIS
    }

    /**
     * This <code>ColorModel</code> should indicate the model used by
     * the majority of calls to <code>setPixels</code>.  Each call to
     * <code>setPixels</code> could however indicate a different
     * <code>ColorModel</code>.
     *
     * @param model the color model to be used most often by setPixels
     * @see ColorModel 
     */
    public  void setColorModel(ColorModel model)
    {
	this.model = model;
    }

    /**
     * The <code>ImageProducer</code> should call this method with a
     * bit mask of hints from any of <code>RANDOMPIXELORDER</code>,
     * <code>TOPDOWNLEFTRIGHT</code>, <code>COMPLETESCANLINES</code>,
     * <code>SINGLEPASS</code>, <code>SINGLEFRAME</code>.
     * 
     * @param flags a bit mask of hints
     */
    public  void setHints(int flags)
    {
	//hints = flags; // FIXME - DO NOT KNOW WHAT TO DO WITH THE HINTS
    }

    /**
     * This function delivers a rectangle of pixels where any
     * pixel(m,n) is stored in the array as a <code>byte</code> at
     * index (n * scansize + m + offset).  
     */
    public  void setPixels(int x, int y, int w, int h, 
			   ColorModel model, byte[] pixels, int offset, int scansize)
    {
	//FIXME - I hate bytes
	int xp, yp;
	for( xp = x; xp < ( x + w); xp++ )
	    for( yp = y; yp < (y + h); yp++ )
		if( xp >= this.x && 
		    yp >= this.y && 
		    xp <= ( this.x + this.width ) && 
		    yp <= ( this.y + this.height ) ) {
		    pixel_bufferb[(yp - this.y) * this.scansize + (xp - this.x) + this.offset] =
			pixels[ offset + yp * scansize + xp ];
		}

    }

    /**
     * This function delivers a rectangle of pixels where any
     * pixel(m,n) is stored in the array as an <code>int</code> at
     * index (n * scansize + m + offset).  
     */
    public  void setPixels(int x, int y, int w, int h, 
			   ColorModel model, int[] pixels, int offset, int scansize)
    {
	int xp, yp;
	for( xp = x; xp < ( x + w); xp++ )
	    for( yp = y; yp < (y + h); yp++ )
		if( xp >= this.x && 
		    yp >= this.y && 
		    xp <= ( this.x + this.width ) && 
		    yp <= ( this.y + this.height ) ) {
		    pixel_bufferi[(yp - this.y) * this.scansize + (xp - this.x) + this.offset] =
			pixels[ offset + yp * scansize + xp ];
		}
    }

    /**
     * The <code>ImageProducer</code> calls this method to indicate a
     * single frame or the entire image is complete.  The method is
     * also used to indicate an error in loading or producing the
     * image.  
     */
    public synchronized void imageComplete(int status)
    {
	this.status = status;
    }

    /**
       @deprecated by getStatus
    */
    public synchronized int status()
    {
	return getStatus();
    }

}