// JavaScript Document

// Control Rollovers for OLLI Navigation
function lvl1down(theElement) {
	if (theElement.className == "downTwist")
		theElement.className = "downTwist";	
	else if (theElement.className == "down")
		theElement.className = "down";
	else
		theElement.className = "over";	
}

function lvl1up(theElement) {
	if (theElement.className == "downTwist")
		theElement.className = "downTwist";	
	else if (theElement.className == "down")
		theElement.className = "down";
	else
	theElement.className = "";	
}

function lvl2down(theElement) {
	if (theElement.className == "down")
		theElement.className = "down";
	else
		theElement.className = "over";	
}

function lvl2up(theElement) {
	if (theElement.className == "down")
		theElement.className = "down";
	else
	theElement.className = "";	
}

// Font size adjuster: http://alistapart.com/articles/alternate
// change style sheet
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;
     }
   }
}

// get current style sheet
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;
}

// drop cookies to hold the style
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;
}

// get preferred style sheet
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;
}

// change style on page load
window.onload = function(e) {
  var cookie = readCookie("style");
  var title = cookie ? cookie : getPreferredStyleSheet();
  setActiveStyleSheet(title);
}

// save style for next visit
window.onunload = function(e) {
  var title = getActiveStyleSheet();
  createCookie("style", title, 365);
}
// end font size adjuster

// Form Validation
// check for an empty string (treat a string with spaces as empty)
function isEmpty(theField) {
	if (theField.value == "") {
		return true;
	}
	else
		return false;
}

// Validate site search form
function siteSearchValidate() {
	if (isEmpty(siteSearch.criteria)) {
		alert("Please specify what you would like to search for.");
		siteSearch.criteria.focus();
		return false;
	}
	else
		return true;
}
// End Form Validation