//create the event handler used by nav links

function showPic(evt)
{
	var myEvent= window.event || evt;
	var target;
	
	if(window.event)
	{
		target= window.event.srcElement;
	}
	else 
	{
		target= evt.target;
	}
	
	var title= target.getAttribute('title');
	var source= target.getAttribute('href');
	
	
	// change the picture
	var pic= document.getElementById('placeholder');
	pic.setAttribute('src',source);
	
	//change the text
	var text= document.getElementById('description');
	text.firstChild.nodeValue=title;
	
}

//This is the function that sets the status indicator for the sidebar links
function setStatus(evt)
{
	//get reference to link clicked on
	var target=evt.target||window.event.srcElement
	
	//get reference to nav 
	var main=document.getElementById('main');
		
	//create ref to all links in nav
	var links=main.getElementsByTagName('A');
	var numLinks=links.length;
	
	//loop over links add event listener
	for(var j=0; j< numLinks;j++)
		{
			changeClassName('remove', links[j], 'statusOn');
			changeClassName('add', links[j], 'statusOff');
		}
		
	//add status indication to link
	changeClassName('add', target, 'statusOnSidebar');	
}

function prepareLinks()
{
	var main=document.getElementById('main');
	var links=document.getElementsByTagName('A');
	
	for(var i=0; i<links.length; i++)
	{
		addEvent(links[i],'click',stopDefault);
		addEvent(links[i],'click',showPic);
		addEvent(links[i],'click',setStatus);
	}
}