function effectShowHide(idSpan, idImage)
 {
 if(document.getElementById(idSpan).style.display == "block")
  {
  effectHide(idSpan, idImage);
  }
 else
  {
  effectShow(idSpan, idImage);
  }
 }

function effectHide(idSpan, idImage)
 {
 document.getElementById(idSpan).style.display = "none";
 document.getElementById(idImage).src = "plus.png";
 
 eraseCookie(idImage);
 }
 
function effectShow(idSpan, idImage)
 {
 document.getElementById(idSpan).style.display = "block";
 document.getElementById(idImage).src = "minus.png";
 
 createCookie(idImage, idSpan, 7);
 }
 
function exeUpdateNavigator()
 {
 document.getElementById("idformNavigate").action = "http://www.princeton.edu/%7Eidodin/" + document.getElementById("idinputNavigate").value;
 }

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 var expires = "";
 document.cookie = name + "=" + value + expires +"; path=/~idodin";
 }

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 eraseCookie(name) 
 {
 createCookie(name, "", -1);
 }
 
function onLoad()
 {
 var idSpan, idImage, objImage;
 
 for(var i = 0; i < document.images.length; i++)
  {
  objImage = document.images[i];
  idImage = objImage.id;
  idSpan = readCookie(idImage);
  if(idSpan != null) 
   effectShow(idSpan, idImage);
  }
 }
 
function onLoadIndex()
 {
 if(navigator.cookieEnabled == false)
  {
  if(navigator.appName == "Microsoft Internet Explorer")
   alert("Full functionality of this site requires 3rd-party cookies enabled.");
  else 
   alert("Full functionality of this site requires cookies enabled.");
  }
  
 var iniPage = readCookie("iniPage");

 if(iniPage != null)
   document.getElementById("idframeMain").src = iniPage;
 else
   document.getElementById("idframeMain").src = "home.htm";
 }