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() {
	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;
}

cookie = readCookie("style");
title = cookie ? cookie : getPreferredStyleSheet();
if (title == "spring" || title == "summer" || title == "fall" || title == "winter"){
	setActiveStyleSheet(title);
} else {
	today = new Date();
	m = today.getMonth();
	if (m==0 || m==1 || m==11){
		setActiveStyleSheet("winter");
	} else if (m==2 || m==3 || m==4){
		setActiveStyleSheet("spring");
	} else if (m==5 || m==6 || m==7){
		setActiveStyleSheet("summer");
	} else{
		setActiveStyleSheet("fall");
	}
}