// JavaScript for event handling on LEARN NC website


// determine which browser is being used; store for reference
var isSafari = navigator.appVersion.indexOf("Safari") != -1;
var isIE = navigator.appName.indexOf("Microsoft") != -1;
var isNNMoz = (navigator.appName.indexOf("Netscape") != -1 && !isSafari);

function addEvent(objObject, strEventName, fnHandler) {
	// Adds event listener to object using DOM model, if available; otherwise tries IE model.
	if (objObject.addEventListener) {
		objObject.addEventListener(strEventName, fnHandler, false);
	}
 	// IE/windows way to add an event listener
	else if (objObject.attachEvent) {
   		objObject.attachEvent("on" + strEventName, fnHandler);
	}
}

function removeEvent(objObject, strEventName, fnHandler, bubble) {
	// Adds event listener to object using DOM model, if available; otherwise tries IE model.
	if (objObject.removeEventListener) {
		objObject.removeEventListener(strEventName, fnHandler, bubble);
	}
 	// IE/windows way to add an event listener
	else if (objObject.detachEvent) {
   		objObject.detachEvent("on" + strEventName, fnHandler);
	}
}

function findEventOwner(evt) {
	if (evt.target) {
		// DOM compliant
		var node = evt.target; 
	}
	else {
		// IE/Win
		var node = evt.srcElement;
	}
	while (node) {
		if ( (node.nodeType == node.ELEMENT_NODE || node.nodeType == 1) ) {
			// node.ELEMENT_NODE does not seem to work in Safari
			return node;
		}
		node = node.parentNode;
		}
	return null;
}