var animationTime = 0.4;
var animationRunning = false;

init();

function init() {
	var object = $($$('div.toc')[0]);
	treeMouseOut(object);
	var elements = object.getElementsBySelector('img.link');
	for (var i = 0; i < elements.length; ++i) {
		$(elements[i]).setOpacity(0.2);
	}
}

function treeMouseOver(object) {
	setTreeSwitchOpacity(object,1.0);
}

function treeMouseOut(object) {
	setTreeSwitchOpacity(object,0.2);
}

function setTreeSwitchOpacity(object, opacity) {
	var elements = $(object).getElementsBySelector('span.switch_expansion img');
	for (var i = 0; i < elements.length; ++i) {
		$(elements[i]).setOpacity(opacity);
	}
}

function expandCollapse(object) {
	if (!animationRunning) {
		animationRunning = true;
		var ul = $(object).siblings()[1];
		if (navigator.appName.indexOf("Explorer") == -1) {
			// non IE
			if (ul.visible()) {
				new Effect.BlindUp(ul,{duration:animationTime,afterFinish: animationFinished});
			} else {
				new Effect.BlindDown(ul,{duration:animationTime,afterFinish: animationFinished});
			}
		} else {
			// IE
			ul.toggle();
			animationRunning = false;
		}
		
		object.getElementsBySelector('img').each(Element.toggle);
	}
}

function animationFinished() {
	animationRunning = false;
}