/***
 * 
 * Copyright (C) 2008 Alessandro La Rosa
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser 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
 *
 * Contact: alessandro.larosa@gmail.com
 *
 * Author: Alessandro La Rosa
 */

import javax.microedition.lcdui.Graphics;

public class ColorFadeText
{
	public int[] colors = null;
	
	public int fadeDuration = 0;
	public long startTime = 0;
	
	boolean started = false;
	
	public String text = null;
	
	public ColorFadeText(String text, int[] colors, int fadeDuration)
	{
		if(colors.length == 0)
		{
			throw new IllegalArgumentException("You must define at least 1 color");
		}
		this.text = text;
		this.colors = colors;
		this.fadeDuration = fadeDuration;
	}
	public void start()
	{
		startTime = System.currentTimeMillis();
		
		started = true;
	}
	public void paint(Graphics g, int x, int y, int anchor)
	{
		if(started)
		{
			long diff = System.currentTimeMillis() - startTime;
			
			int module = (int)(diff % fadeDuration);
			
			int colorIndex = (int)(diff / fadeDuration) % colors.length;
			
			int midColor = midColor(				
				colors[(colorIndex + 1) % colors.length],
				colors[colorIndex], 
				module, 
				fadeDuration
			);
			
			g.setColor(midColor);
		}
		else
		{
			g.setColor(colors[0]);
		}
		
		g.drawString(text, x, y, anchor);
	}
	static int midColor(int color1, int color2, int prop, int max)
	{
		int red = 
			(((color1 >> 16) & 0xff) * prop +
			((color2 >> 16) & 0xff) * (max - prop)) / max;
		
		int green = 
			(((color1 >> 8) & 0xff) * prop +
			((color2 >> 8) & 0xff) * (max - prop)) / max;
		
		int blue = 
			(((color1 >> 0) & 0xff) * prop +
			((color2 >> 0) & 0xff) * (max - prop)) / max;
		
		int color = red << 16 | green << 8 | blue;
		
		return color;
	}
}