/*******************************************************************************
 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
 * in Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.utils.ui.color;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseListener;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Text;

/**
 * 
 * Widget to edit colors
 * 
 * @author Marko Luukkainen
 *
 */
public class ColorComposite extends Composite{
	
	
	private Color color = new Color(255,255,255);
	private ColorGradient rGradient;
	private ColorGradient gGradient;
	private ColorGradient bGradient;
	private ColorGradient colorGradient;
	
	Text rText;
	Text gText;
	Text bText;
	ColorGradientCanvas rCanvas;
	ColorGradientCanvas gCanvas;
	ColorGradientCanvas bCanvas;
	ColorGradientCanvas colorCanvas;
	
	
	public ColorComposite(Composite parent, int style) {
		super(parent,style);
		updateGradients();
		
		GridLayout layout = new GridLayout();
		layout.makeColumnsEqualWidth = false;
		layout.numColumns = 3;
		this.setLayout(layout);
		
		colorCanvas = new ColorGradientCanvas(this,SWT.BORDER|SWT.HORIZONTAL);
		GridData colorCanvasData = new GridData();
		colorCanvasData.horizontalSpan = 3;
		colorCanvasData.heightHint = 32;
		colorCanvasData.widthHint = 600;
		colorCanvasData.grabExcessHorizontalSpace = true;
		colorCanvas.setLayoutData(colorCanvasData);
		
		//layout data used with labels
		GridData labelData = new GridData();
		labelData.widthHint = 30;
		//layout data used with gradients
		GridData gradientData = new GridData();
		gradientData.grabExcessHorizontalSpace = true;
		gradientData.heightHint = 16;
		gradientData.widthHint = 500;
		//layout data used with texts
		GridData textData = new GridData();
		textData.widthHint = 30;
		
		
		//Composite rComposite = new Composite(this,SWT.NONE);
		//Layout rLayout = new FillLayout(SWT.HORIZONTAL);
		//rComposite.setLayout(rLayout);
		Label rLabel = new Label(this,SWT.NONE);
		rLabel.setText("Red");
		rLabel.setLayoutData(labelData);
		rCanvas = new ColorGradientCanvas(this,SWT.BORDER|SWT.HORIZONTAL);
		rCanvas.setLayoutData(gradientData);
		rText = new Text(this,SWT.BORDER);
		rText.setLayoutData(textData);
		rCanvas.addMouseListener(new ColorSelectListener(rCanvas) {
			void setValue(int value) {
				Color newColor = new Color(value,color.getG(),color.getB());
				updateColor(newColor);
			};
		});
		
		//Composite gComposite = new Composite(this,SWT.NONE);
		//Layout gLayout = new FillLayout(SWT.HORIZONTAL);
		//gComposite.setLayout(gLayout);
		Label gLabel = new Label(this,SWT.NONE);
		gLabel.setText("Green");
		gLabel.setLayoutData(labelData);
		gCanvas = new ColorGradientCanvas(this,SWT.BORDER|SWT.HORIZONTAL);
		gCanvas.setLayoutData(gradientData);
		gText = new Text(this,SWT.BORDER);
		gText.setLayoutData(textData);
		gCanvas.addMouseListener(new ColorSelectListener(gCanvas) {
			void setValue(int value) {
				Color newColor = new Color(color.getR(),value,color.getB());
				updateColor(newColor);
			};
		});
		
		//Composite bComposite = new Composite(this,SWT.NONE);
		//Layout bLayout = new FillLayout(SWT.HORIZONTAL);
		//bComposite.setLayout(bLayout);
		Label bLabel = new Label(this,SWT.NONE);
		bLabel.setText("Blue");
		bLabel.setLayoutData(labelData);
		bCanvas = new ColorGradientCanvas(this,SWT.BORDER|SWT.HORIZONTAL);
		bCanvas.setLayoutData(gradientData);
		bText = new Text(this,SWT.BORDER);
		bText.setLayoutData(textData);
		bCanvas.addMouseListener(new ColorSelectListener(bCanvas) {
			void setValue(int value) {
				Color newColor = new Color(color.getR(),color.getG(),value);
				updateColor(newColor);
			};
		});
		updateWidgets();
		
	}
	
	private abstract class ColorSelectListener implements MouseListener {
		private Canvas canvas;
		
		public ColorSelectListener(Canvas canvas) {
			this.canvas = canvas;
		}
		public void mouseDoubleClick(MouseEvent e) {
						
		}
		public void mouseDown(MouseEvent e) {
			Rectangle r = this.canvas.getBounds();
			double d = (double)e.x / (double)r.width;
			int value = (int)(d * 255);
			if (value < 0)
				value = 0;
			if (value > 255)
				value = 255;
			setValue(value);
			
		}
		public void mouseUp(MouseEvent e) {
			
		}
		
		abstract void setValue(int value);
	}
	
	private void updateColor(Color color) {
		this.color = color;
		updateWidgets();
	}
	
	private void updateGradients() {
		rGradient = new ColorGradient(new ColorValue[]{
					new ColorValue(new Color(0,color.getG(),color.getB()),0.0),
					new ColorValue(new Color(255,color.getG(),color.getB()),1.0)});
		gGradient = new ColorGradient(new ColorValue[]{
				new ColorValue(new Color(color.getR(),0,color.getB()),0.0),
				new ColorValue(new Color(color.getR(),255,color.getB()),1.0)});
		bGradient = new ColorGradient(new ColorValue[]{
				new ColorValue(new Color(color.getR(),color.getG(),0),0.0),
				new ColorValue(new Color(color.getR(),color.getG(),255),1.0)});
		colorGradient = new ColorGradient(new ColorValue[]{
				new ColorValue(new Color(color.getR(),color.getG(),color.getB()),0.0)});
	
	}
	
	private void updateWidgets() {
		updateGradients();
		rCanvas.setGradient(rGradient);
		gCanvas.setGradient(gGradient);
		bCanvas.setGradient(bGradient);
		colorCanvas.setGradient(colorGradient);
		rText.setText(Integer.toString(color.getR()));
		gText.setText(Integer.toString(color.getG()));
		bText.setText(Integer.toString(color.getB()));	
	}
}