window.onload = function() {
	initRollover();
	prepareDtToggle();
}

function initRollover() {
	var menu = document.getElementById("top-nav");
	var left_nav = document.getElementById("left-nav");
	
	if(menu) {
		var menu_items = menu.getElementsByTagName("A");
		
		for(var i = 0; i < menu_items.length; i++) {
				
				if(menu_items[i].className == "current-page") {
					var old_image = menu_items[i].childNodes[0].src;  
					var new_image = old_image.replace(/(\.gif|\.jpg|.png)/, "_on$&");
					menu_items[i].childNodes[0].src = new_image;
				}
		}
	}  
	
	if(left_nav) {
		var left_menu_items = left_nav.getElementsByTagName("A");
		
		for(var i = 0; i < left_menu_items.length; i++) {
				
				if(left_menu_items[i].className == "current-page") {
					var old_image = left_menu_items[i].childNodes[0].src;  
					var new_image = old_image.replace(/(\.gif|\.jpg|.png)/, "_on$&");
					left_menu_items[i].childNodes[0].src = new_image;
				}
		}
	}  
}


function prepareDtToggle() {
	var speaker_list = document.getElementById("speaker_list");
	if(!speaker_list) return false;
	
	var speakers = speaker_list.getElementsByTagName("dt");
	if(!speakers) return false;
	
	var collapseControls = speaker_list.getElementsByTagName("a");
	
	var toggleControls = new Array;
	
	for (var i=0; i < speakers.length; i++) {
		var links = speakers[i].getElementsByTagName("a");
		
		for (var j=0; j < links.length; j++) {
			toggleControls[i] = links[j];
		}
	}
	
	for (var m=0; m < collapseControls.length; m++) {
		if(collapseControls[m].className = "collapse") {
			collapseControls[m].onclick = function() {
				collapseSpeakers();
			}
		}
	}
	
	for (var k=0; k < toggleControls.length; k++) {
		toggleControls[k].onclick = function() {
			dtToggle(this.parentNode.parentNode);
		}
		dtToggle(toggleControls[k].parentNode.parentNode);
	}
}

function dtToggle(dt) {
	var sibling = (dt.nextSibling.nodeType==3)? dt.nextSibling.nextSibling : dt.nextSibling;
	if(!sibling.className || sibling.className == "" || sibling.className == "show clearfix") {
		sibling.className = "hide";
    }
	else {
		sibling.className = "show clearfix";
    }
}

function collapseSpeakers() {
	var bios = document.getElementsByTagName("dd");
	
	for (i = 0; i < bios.length; i++) {
		bios[i].className = "hide";
	}
	
}