var acessibilidade = {

	aumentarFonte:function() {
	this.fontePadrao();
	elms = document.getElementsByTagName("*");
	
		for (var x=0; x<elms.length; x++) {
			strFont = getStyle(elms[x],'font-size') || getStyle(elms[x],'fontSize');
			strFont = strFont.substring(0,strFont.indexOf("px"));
			
			if (strFont < 14) {
			elms[x].style.fontSize = (strFont*1) + 1 + "px";
			elms[x].fonteAlterada = true;
			}
		}
	},
	
	diminuirFonte:function() {
	this.fontePadrao();
	elms = document.getElementsByTagName("*");
	
		for (var x=0; x<elms.length; x++) {
			strFont = getStyle(elms[x],'font-size') || getStyle(elms[x],'fontSize');
			strFont = strFont.substring(0,strFont.indexOf("px"));
			
			if (strFont > 11) {
			elms[x].style.fontSize = (strFont*1) - 1 + "px";
			elms[x].fonteAlterada = true;
			}
		}
	},
	
	fontePadrao:function() {
	elms = document.getElementsByTagName("*");
	
		for (var x=0; x<elms.length; x++) {
			if (elms[x].fonteAlterada) return false;
			
			strFont = getStyle(elms[x],'font-size') || getStyle(elms[x],'fontSize');
			strFont = strFont.substring(0,strFont.indexOf("px"));
			
			elms[x].fontePadrao = strFont;
		}
	},
	
	restaurarPadrao:function() {
	elms = document.getElementsByTagName("*");
	
		for (var x=0; x<elms.length; x++) {
			if (elms[x].fontePadrao) {
			elms[x].style.fontSize = elms[x].fontePadrao + "px";
			}
		}
	},
	
	altoConstrate:function() {
		setActiveStyleSheet("contraste")
	},
	
	contrastePadrao:function() {	
		setActiveStyleSheet("standard")
	}
	
}

function getStyle(elm,styleProp)
{
	var x = elm;
	if (x.currentStyle)
		var y = x.currentStyle[styleProp];
	else if (window.getComputedStyle)
		var y = document.defaultView.getComputedStyle(x,null).getPropertyValue(styleProp);
	return y;
}

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);