function textUp() {
  enable('text-down');
  active = getActiveStyleSheet();
  switch (active) {
    case 'text-smallest' : 
      enable('text-up');
      setActiveStyleSheet('text-smaller');
      break;
    case 'text-smaller' : 
	   enable('text-up');
	   setActiveStyleSheet('text-normal');
      break;
    case 'text-normal' : 
		enable('text-up');
		setActiveStyleSheet('text-bigger');
      break;
    case 'text-bigger' : 
	  disable('text-up');
      setActiveStyleSheet('text-biggest');
      break;
    case 'text-biggest' :
      break;
    default :
      setActiveStyleSheet('A');
      break;
  }
}

function textDown() {
  enable('text-up');
  active = getActiveStyleSheet();
  switch (active) {
    case 'text-biggest' : 
      enable('text-down');
	  setActiveStyleSheet('text-bigger');
      break;
    case 'text-bigger' :
	  enable('text-down');
      setActiveStyleSheet('text-normal');
      break;
    case 'text-normal' : 
      enable('text-down');
      setActiveStyleSheet('text-smaller');
      break;
    case 'text-smaller' : 
		disable('text-down');
      setActiveStyleSheet('text-smallest');
      break;
    case 'text-smallest' : 
		break;
    default :
      setActiveStyleSheet('text-smallest');
      break;
  }
}

function enable(id) {
  var button = document.getElementById(id);
  var image = button.getElementsByTagName("img")[0];
  //var image = document.getElementById(id);
  if (navigator.appName.indexOf("Netscape")!=-1&&parseInt(navigator.appVersion)>=5) {
    image.style.MozOpacity=1.0 //NS6 syntax
  } else if(navigator.appName.indexOf("Microsoft")!=-1&&parseInt(navigator.appVersion)>=4) {
	image.style.filter = "alpha(opacity:100)";
  }
}

function setOpacity(obj, opacity) {
  opacity = (opacity == 100)?99.999:opacity;
  
  // IE/Win
  obj.style.filter = "alpha(opacity:"+opacity+")";
  
  // Safari<1.2, Konqueror
  obj.style.KHTMLOpacity = opacity/100;
  
  // Older Mozilla and Firefox
  obj.style.MozOpacity = opacity/100;
  
  // Safari 1.2, newer Firefox and Mozilla, CSS3
  obj.style.opacity = opacity/100;
}

function disable(id) {
  var button = document.getElementById(id);
  var image = button.getElementsByTagName("img")[0];
  //var image = document.getElementById(id);
  if (navigator.appName.indexOf("Netscape")!=-1&&parseInt(navigator.appVersion)>=5) {
    image.style.MozOpacity=0.5 //NS6 syntax
  } else if(navigator.appName.indexOf("Microsoft")!=-1&&parseInt(navigator.appVersion)>=4) {
	image.style.filter = "alpha(opacity:50)";
  }
}

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")) {
		if(!a.disabled) {
			return a.getAttribute("title");
		}
	}
  }
  return null;
}

function getPreferredStyleSheet() {
  return ('text-smaller');
}

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;
}

function setButtonInitialState(title) {
	if (title=='text-biggest'){disable('text-up');}
	if (title=='text-smallest'){disable('text-down');} 
	return null;
}

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

window.onunload = function(e) {
  var title = getActiveStyleSheet();
  createCookie("style", title, 365);
}

var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
if (title == 'null') {
  title = getPreferredStyleSheet();
}

setActiveStyleSheet(title);