var cookieName = 'emba_show_sidenav';
var sideNavId = 'page-toc';
var toggleButtonId = 'toggleSideBarBtn';
var toggleTextLinkId = 'text-toggle-nav';
var newWindowBtn = 'newWindowBtn';
var contentDivId = 'sectioncontent';
var embaWindow = '';
var embaWindowName ='emba_coursetext';
var embaCollapsePageImg = '../../../images/next_arr.gif';
var embaExpandPageImg = '../../../images/prev_arr.gif';
var expires = '';

function createCookie(name,value,days)
{
	if (days)
	{
		var date = new Date();
		date.setTime(date.getTime()+(days*24*60*60*1000));
		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 eraseCookie(name)
{
	createCookie(name,"",-1);
}

function getObj(name)
{
  if (document.getElementById && document.getElementById(name))
  {
  	this.obj = document.getElementById(name);
	this.style = document.getElementById(name).style;
  }
  else if (document.all && document.all[name])
  {
	this.obj = document.all[name];
	this.style = document.all[name].style;
  }
  else if (document.layers && document.layers[name])
  {
   	this.obj = document.layers[name];
   	this.style = document.layers[name];
  }
}


function toggleNav(){
  var navObj = new getObj(sideNavId);
  if (navObj.style){
    createCookie(cookieName, ((navObj.style.display == 'none') ? '1' : '0')); 
    showhideNav();
  }
}

function show_props(obj, obj_name) {
   var result = "";
   for (var i in obj)
      if (obj[i] !== null)
      result += obj_name + "." + i + " = " + obj[i] + "\n";
   return result
} 

function showhideNav(){
  var navObj = new getObj(sideNavId);
  var contentObj = new getObj(contentDivId);
 /* var topMenuObj = new getObj('top-menu');
  var bottomMenuObj = new getObj('bottom-menu');*/

  if (document.getElementById(toggleButtonId)) {
  	var toggleBtnObj = new getObj(toggleButtonId);
  } else if (document.getElementById(toggleTextLinkId)) {
  	var toggleBtnObj = new getObj(toggleTextLinkId);
  }
  /* check the document cookie to see if the sidenav should be displayed */
  if (navObj && navObj.style){
    if (readCookie(cookieName) == '0'){
      // the sidenav should be hidden
      navObj.style.display = 'none';
      contentObj.style.marginRight = '70px';  			
/*      topMenuObj.style.marginRight = '0';
      bottomMenuObj.style.marginRight = '0';  */
      if (toggleBtnObj.obj.src) {
      	toggleBtnObj.obj.src = embaExpandPageImg;
      	toggleBtnObj.obj.alt = 'Show side navigation';    
      }else{
	document.getElementById(toggleTextLinkId).innerHTML = 'Show Panel';
      }
    }else{
      // the sidenav should be displayed
      navObj.style.display = 'block';
      contentObj.style.marginRight = '19em';  
    /*  topMenuObj.style.marginRight = '210px';
      bottomMenuObj.style.marginRight = 18em';*/
      if (toggleBtnObj.obj.src) {
         toggleBtnObj.obj.src = embaCollapsePageImg;
         toggleBtnObj.obj.alt = 'Hide side navigation';    
      } else {
         document.getElementById(toggleTextLinkId).innerHTML = 'Hide Panel';
      }
    }
  }else{
  	if (document.getElementById(toggleTextLinkId)){
  	   document.getElementById(toggleTextLinkId).innerHTML = '';
  	   
  	} else {
  	   var buttonObj = new getObj(toggleButtonId);
  	   buttonObj.style.display = 'none';
  	}
  }


  /* now check to see if we need to show the 'open in new window' button */
  if (window.name == embaWindowName) {// this is the new window so we need to hide the button
    var newWinBtnObj = new getObj(newWindowBtn);
    newWinBtnObj.style.display = 'none'
  }
  
  
  
}

function newWindow(url)
{
	if (window.name == embaWindowName)
		return false;	// if this already the embaWindow do nothing 
	if (!embaWindow.closed && embaWindow.location)
	{
		embaWindow.location.href = url;
	}
	else
	{
		embaWindow=window.open(url, embaWindowName);
		if (!embaWindow.opener) embaWindow.opener = self;
	}
	if (window.focus) {embaWindow.focus()}
	return false;
}

function showHide(element,goToElement) {
	if (document.getElementById(element)) {
		if (document.getElementById(element).style.display == 'block') {
			document.getElementById(element).style.display = 'none';
		}
		else {
			document.getElementById(element).style.display = 'block';
		}
		if (goToElement && goToElement != ''){
			location.href = "#" + goToElement;
			alert (location.href);	
		}
	}
}

function hideShow(element) {
	if (document.getElementById(element).style.display == 'none') {
		document.getElementById(element).style.display = 'block';
	}
	else {
		document.getElementById(element).style.display = '';
	}
}

function showCurrent(element, className) {
	var divTags = document.body.getElementsByTagName('div');
	for (i = 0; i < divTags.length; i++) {
		if(divTags[i].className == className) {
			divTags[i].style.display = 'none';
		}
	}
	document.getElementById(element).style.display = 'block';
}

function hide(element) {
	if (document.getElementById(element)) {
		document.getElementById(element).style.display = 'none';
	}
}