/**
 * Compose two RGB image series as a YCbCr merge.
 *
 * The result has the luminance of series `target' and the
 * Cb and Cr channels of `source'.  That looks like using the `color' of
 * `source' over `target' but is not exactly that because Cb and Cr still
 * carry some luminance information.  That is, color over black or white will
 * not be black or white but visible color.
 *
 * @author Stephan Saalfeld <saalfeld@mpi-cbg.de>
 *
 */
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;

import ij.IJ;
import ij.ImagePlus;
import ij.ImageStack;
import ij.WindowManager;
import ij.gui.GenericDialog;
import ij.plugin.PlugIn;
import ij.process.ColorProcessor;
import ini.trakem2.display.graphics.*;
import java.awt.Composite;

Composite getComposite( int mode, float alpha )
{
	switch ( mode )
	{
	case 1:
		return AddARGBComposite.getInstance( alpha );
	case 2:
		return SubtractARGBComposite.getInstance( alpha );
	case 3:
		return MultiplyARGBComposite.getInstance( alpha );
	case 4:
		return DifferenceARGBComposite.getInstance( alpha );
	case 5:
		return ColorYCbCrComposite.getInstance( alpha );
	default:
		return AlphaComposite.getInstance( AlphaComposite.SRC_OVER, alpha );
	}
}

int[] ids = WindowManager.getIDList();

if ( ids == null || ids.length == 0 ) return;

String[] titles = new String[ ids.length ];
		
for ( int i = 0; i < ids.length; ++i )
	titles[ i ] = WindowManager.getImage( ids[ i ] ).getTitle();

String[] modes = new String[]{
		"Normal",
		"Add",
		"Subtract",
		"Multiply",
		"Difference",
		"Color (YCbCr)" };

GenericDialog gd = new GenericDialog( "Compose Stacks" );
gd.addChoice( "source : ", titles,  titles[ 0 ] );
gd.addChoice( "target : ", titles,  titles[ 1 ] );
gd.addChoice( "composition method : ", modes, modes[ 5 ] );
gd.addSlider( "alpha : ", ( double )0.0, ( double )1.00001, 1.0 );

gd.showDialog();

if ( gd.wasCanceled() ) return;

ImagePlus impSource = WindowManager.getImage( ids[ gd.getNextChoiceIndex() ] );
ImagePlus impTarget = WindowManager.getImage( ids[ gd.getNextChoiceIndex() ] );
int mode = gd.getNextChoiceIndex();
composite = getComposite( mode, ( float )Math.max( 0.0, Math.min( 1.0, gd.getNextNumber() ) ) );

ImageStack sSource = impSource.getStack();
ImageStack sTarget = impTarget.getStack();

if (
		impSource.getType() != ImagePlus.COLOR_RGB || impTarget.getType() != ImagePlus.COLOR_RGB ||
		impSource.getImageStackSize() != impTarget.getImageStackSize() ||
		impSource.getWidth() != impTarget.getWidth() || 
		impSource.getHeight() != impTarget.getHeight() )
{
	IJ.error( "Both stacks must be RGB and of the same size." );
	return;
}

n = impTarget.getImageStackSize();

for ( int i = 1; i <= n; ++i )
{
	IJ.showProgress( i - 1, n );
	
	BufferedImage src = sSource.getProcessor( i ).getBufferedImage();
	BufferedImage dst = sTarget.getProcessor( i ).getBufferedImage();
	
	Graphics2D g = dst.createGraphics();
	g.setComposite( composite );
	
	g.drawImage( src, 0, 0, null );
	
	sTarget.setPixels( new ColorProcessor( dst ).getPixels(), i );
	impTarget.setStack( impTarget.getTitle(), sTarget );
	impTarget.updateAndDraw();
	
}
IJ.showProgress( n, n );
impTarget.updateAndDraw();