function mudaCor(a)
{
	var activa = getActiveStyleSheet();
	if(a=='i' && activa.indexOf("inverso")>1)
	{
		return;
	}
	else if(a=='n' && activa.indexOf("normal")>1)
	{
		return;
	}
	else
	{

		if(a=='i')
		{
			switch(activa)
			{
				case "normal": 
					setActiveStyleSheet("normalInverso")
				break;
				case "normalGrande": 
					setActiveStyleSheet("grandeInverso")
				break;
				case "normalExtraGrande": 
					setActiveStyleSheet("extraGrandeInverso")
				break;
			}
		}
		else if(a=='n')
		{
			switch(activa)
			{
				case "normalInverso": 
					setActiveStyleSheet("normal")
				break;
				case "grandeInverso": 
					setActiveStyleSheet("normalGrande")
				break;
				case "extraGrandeInverso": 
					setActiveStyleSheet("normalExtraGrande")
				break;
			}
		}
	}

}

function maisFonte()
{
	var activa = getActiveStyleSheet();
	switch(activa)
	{
		case "normal": 
			setActiveStyleSheet("normalGrande")
		break;
		case "normalGrande": 
			setActiveStyleSheet("normalExtraGrande")
		break;		
		case "normalInverso": 
			setActiveStyleSheet("grandeInverso")
		break;
		case "grandeInverso": 
			setActiveStyleSheet("extraGrandeInverso")
		break;
	}
	
}

function menosFonte()
{
	var activa = getActiveStyleSheet();
	switch(activa)
	{
		case "normalGrande": 
			setActiveStyleSheet("normal")
		break;
		case "normalExtraGrande": 
			setActiveStyleSheet("normalGrande")
		break;		
		case "grandeInverso": 
			setActiveStyleSheet("normalInverso")
		break;
		case "extraGrandeInverso": 
			setActiveStyleSheet("grandeInverso")
		break;
	}
	
}

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");
  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);