function setActiveStyleSheetCursor(title) {
if(window.event.keyCode == 13) {
activarHojaEstilos(title)
}
}

function activarHojaEstilos(title) {
	var title_actual = getActiveStyleSheet();
	if (title_actual == null) {
		title = "normal-normal";
	} else {
		var guion = title_actual.indexOf("-");
		switch (title) {
			case "tamano-normal":
				title = "normal" + title_actual.substring(guion, title_actual.length);
				break;
			case "tamano-grande":
				title = "grande" + title_actual.substring(guion, title_actual.length);
				break;
			case "estilo-normal":
				title = title_actual.substring(0, guion) + "-normal";
				break;
			case "estilo-altocontraste1":
				title = title_actual.substring(0, guion) + "-altocontraste1";
				break;
			case "estilo-altocontraste2":
				title = title_actual.substring(0, guion) + "-altocontraste2";
				break;
		}
	}
	setActiveStyleSheet(title);
}

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;
}
}
}
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;
}
window.onload = function(e) {
var cookie = readCookie("style");
if ((cookie == "s1") || (cookie == "s2") || (cookie == "s3"))  {
cookie="";
}
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);
}
window.onunload = function(e) {
var title = getActiveStyleSheet();
createCookie("style", title, 365);
}
var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);