// @name      The Fade Anything Technique
// @namespace http://www.axentric.com/aside/fat/
// @version   1.0-RC1
// @author    Adam Michela

/*  Hightlights new blocks  insert: <div id="paragraph1" class="fade-E67373"> </div>  E67373 is the fade from color 
<p id="p7" class="fade-E67373">
</p>
http://www.axentric.com/posts/default/7
Fade an element after the page load from a script (such as after an Ajax transaction):

Fat.fade_element("paragraph1")The Fat.fade_element() function accepts several arguments: Target ID, Frames Per Second, Fade Duration, Fade Color, Final Color.

For example, if you wanted to fade paragraph1 from red to green at 60 frames per second for 10 seconds:

Fat.fade_element("paragraph1", 60, 10000, "#FF0000", "#00CC00")

*/

var Fat = {
	make_hex : function (r,g,b) 
	{
		r = r.toString(16); if (r.length == 1) r = '0' + r;
		g = g.toString(16); if (g.length == 1) g = '0' + g;
		b = b.toString(16); if (b.length == 1) b = '0' + b;
		return "#" + r + g + b;
	},
	fade_all : function ()
	{
		var a = document.getElementsByTagName("*");
		for (var i = 0; i < a.length; i++) 
		{
			var o = a[i];
			var r = /fade-?(\w{3,6})?/.exec(o.className);
			if (r)
			{
				if (!r[1]) r[1] = "";
				if (o.id) Fat.fade_element(o.id,null,null,"#"+r[1]);
			}
		}
	},
	fade_element : function (id, fps, duration, from, to) 
	{
		if (!fps) fps = 30;
		if (!duration) duration = 3000;
		if (!from || from=="#") from = "#FFFF33";
		if (!to) to = this.get_bgcolor(id);
		
		var frames = Math.round(fps * (duration / 1000));
		var interval = duration / frames;
		var delay = interval;
		var frame = 0;
		
		if (from.length < 7) from += from.substr(1,3);
		if (to.length < 7) to += to.substr(1,3);
		
		var rf = parseInt(from.substr(1,2),16);
		var gf = parseInt(from.substr(3,2),16);
		var bf = parseInt(from.substr(5,2),16);
		var rt = parseInt(to.substr(1,2),16);
		var gt = parseInt(to.substr(3,2),16);
		var bt = parseInt(to.substr(5,2),16);
		
		var r,g,b,h;
		while (frame < frames)
		{
			r = Math.floor(rf * ((frames-frame)/frames) + rt * (frame/frames));
			g = Math.floor(gf * ((frames-frame)/frames) + gt * (frame/frames));
			b = Math.floor(bf * ((frames-frame)/frames) + bt * (frame/frames));
			h = this.make_hex(r,g,b);
		
			setTimeout("Fat.set_bgcolor('"+id+"','"+h+"')", delay);

			frame++;
			delay = interval * frame; 
		}
		setTimeout("Fat.set_bgcolor('"+id+"','"+to+"')", delay);
	},
	set_bgcolor : function (id, c)
	{
		var o = document.getElementById(id);
		o.style.backgroundColor = c;
	},
	get_bgcolor : function (id)
	{
		var o = document.getElementById(id);
		while(o)
		{
			var c;
			if (window.getComputedStyle) c = window.getComputedStyle(o,null).getPropertyValue("background-color");
			if (o.currentStyle) c = o.currentStyle.backgroundColor;
			if ((c != "" && c != "transparent") || o.tagName == "BODY") { break; }
			o = o.parentNode;
		}
		if (c == undefined || c == "" || c == "transparent") c = "#FFFFFF";
		var rgb = c.match(/rgb\s*\(\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\s*\)/);
		if (rgb) c = this.make_hex(parseInt(rgb[1]),parseInt(rgb[2]),parseInt(rgb[3]));
		return c;
	}
}

window.onload = function () 
	{
	Fat.fade_all();
	}