function setActiveStyleSheet(title) {
	var calc = new Array();
	calc[2] = true;

	for(calc[0] = 0; calc[1] = document.getElementsByTagName("link")[calc[0]]; calc[0]++){
		if(calc[1].getAttribute("rel").indexOf("style") != -1 && calc[1].getAttribute("title")) {
			calc[1].disabled = true;
			if(calc[1].getAttribute("title") == title){
				calc[1].disabled = false;
				calc[2] = false;
			}
		}
	}

	if(calc[2]) setActiveStyleSheet(getPreferredStyleSheet());
}

function getActiveStyleSheet() {
	var calc = new Array();

	for(calc[0] = 0; calc[1] = document.getElementsByTagName("link")[calc[0]]; calc[0]++){
		if( calc[1].getAttribute("rel").indexOf("style") != -1
		 && calc[1].getAttribute("title")
		 && !calc[1].disabled
		) return calc[1].getAttribute("title");
	}

	return null;
}

function getPreferredStyleSheet() {
	var calc = new Array();

	for(calc[0] = 0; calc[1] = document.getElementsByTagName("link")[calc[0]]; calc[0]++){
		if( calc[1].getAttribute("rel").indexOf("style") != -1
		 && calc[1].getAttribute("rel").indexOf("alternate") == -1
		 && calc[1].getAttribute("title")
		) return calc[1].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;
}

var StyleSwitcher_onload = window.onload;
var StyleSwitcher_unload = window.onunload;

window.onload = function(){
	if(typeof StyleSwitcher_onload == 'function') StyleSwitcher_onload();
	var cookie = readCookie("style");
	var title = cookie ? cookie : getPreferredStyleSheet();
	setActiveStyleSheet(title);
}

window.onunload = function(){
	if(typeof StyleSwitcher_unload == 'function') StyleSwitcher_unload();
	var title = getActiveStyleSheet();
	createCookie("style", title, 365);
}