/* Adaptación del script original de Paul Sowden (http://www.idontsmoke.co.uk/) 
 * descrito en el artículo "Alternative Style: Working with Alternate Style 
 * Sheets" (http://alistapart.com/stories/alternate/) para las parrillas de 
 * programación de Canal Satélite Digital en mundoplus.tv
 * 
 * Las modificaciones han sido la adición de la variable 'cookieName', la función
 * 'selectStyle()', la vida de la cookie (de 365 a 60 días) y este comentario.
 *
 * $ID: styleswitcher.js, 2001/12/22 Antonio Bueno, atnbueno@mundoplus.tv
 */

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;
}

cookieName = "mundoplus[formato_parrillas]";

window.onload = function(e) {
	var cookie = readCookie(cookieName);
	var title = cookie ? cookie : getPreferredStyleSheet();
	setActiveStyleSheet(title);
}

window.onunload = function(e) {
	var title = getActiveStyleSheet();
	createCookie(cookieName, title, 60);
}

var cookie = readCookie(cookieName);
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);

function selectStyle(style) {
	if (style != "") {
		setActiveStyleSheet(style);
	}
}