// IE Mac compatibility code (prototypes ROCK!)
if(typeof Array.prototype.push=='undefined')
  Array.prototype.push=function(){
    var i=0;
    b=this.length,a=arguments;
    for(i;i<a.length;i++)this[b+i]=a[i];
    return this.length
  };

// Utility Functions
window.loadTasks = new Array();
window.unloadTasks = new Array();
window.onload = driverInit;
window.onunload = driverFinish;

function registerLoadTask(fn) {
	window.loadTasks.push(fn);
}

function registerUnloadTask(fn) {
	window.unloadTasks.push(fn);
}

function driverInit() {
	for(var i in window.loadTasks) {
		if(typeof window.loadTasks[i] == 'string')
			eval(window.loadTasks[i]);
	}
}

function driverFinish() {
	for(var i in window.unloadTasks) {
		eval(window.unloadTasks[i]);
	}
}

function setActiveStyleSheet(title) {
  var i, a, main;
  for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title")) {
      a.disabled = true;
      if(a.getAttribute("title") == title) a.disabled = false;
    }
  }
  createCookie("style", title, 365);
}

function getActiveStyleSheet() {
  var i, a;
  for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title") && !a.disabled) return a.getAttribute("title");
  }
  return null;
}

function getPreferredStyleSheet() {
  var i, a;
  for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if(a.getAttribute("rel").indexOf("style") != -1
       && a.getAttribute("rel").indexOf("alt") == -1
       && a.getAttribute("title")
       ) return a.getAttribute("title");
  }
  return null;
}

function createCookie(name,value,days) {
  if (days) {
    var date = new Date();
    date.setTime(date.getTime()+(days*24*60*60*1000));
    var expires = "; expires="+date.toGMTString();
  }
  else expires = "";
  document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
  var nameEQ = name + "=";
  var ca = document.cookie.split(';');
  for(var i=0;i < ca.length;i++) {
    var c = ca[i];
    while (c.charAt(0)==' ') c = c.substring(1,c.length);
    if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
  }
  return null;
}

function styleSwitcherOnLoad() {
  var cookie = readCookie("style");
  var title = cookie ? cookie : getPreferredStyleSheet();
  setActiveStyleSheet(title);
}

function styleSwitcherOnUnload() {
  var title = getActiveStyleSheet();
  createCookie("style", title, 365);
}

/*
var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);
*/

registerLoadTask('styleSwitcherOnLoad()');
registerUnloadTask('styleSwitcherOnUnload()');