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

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 ()
  {
    if(!document.getElementById) return;
    if(!document.getElementsByTagName) return;
    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 = "#ffffcc";
    if (!to) to = this.get_bgcolor(id);
    
    var f = document.getElementById(id+"_f");
    if (f) f.focus();

    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);
    if(!o) return;
    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();
  }*/