/*
Author: mg12
Update: 2008/11/27
Author URI: http://www.neoease.com/
*/
(function() {

var Class = {
	create: function() {
		return function() {
			this.initialize.apply(this, arguments);
		}
	}
}

var GhostlyMenu = Class.create();
GhostlyMenu.prototype = {

	initialize: function(target, align, opacity, offset) {
		this.obj = cleanWhitespace(target);
		this.align = align || 'left';
		this.opacity = 0;
		this.maxopacity = opacity || 1;
		this.offset = offset || 0;

		this.menu = this.obj.childNodes
		if (this.menu.length < 2) { return; }

		this.title = this.menu[0];
		this.body = this.menu[1];

		cleanWhitespace(this.body).firstChild.className = 'first';

		if (/MSIE/i.test(navigator.userAgent)) {
			var readers = getElementsByClassName('reader', 'a', this.body);
			for (var i = 0; i < readers.length; i++) {
				setStyle(readers[i], 'cursor', 'hand');
			}
		}

		setStyle(this.body, 'visibility', 'hidden');
		setStyle(this.body, 'position', 'absolute');
		setStyle(this.body, 'overflow', 'hidden');
		setStyle(this.body, 'display', 'block');

		addListener(this.obj, 'mouseover', bind(this, this.activate), false);
		addListener(this.obj, 'mouseout', bind(this, this.deactivate), false);
	},

	activate: function() {
		var pos = cumulativeOffset(this.title);
		var left = pos[0];
		if (this.align == 'right') {
			var offset = getWidth(this.title) - getWidth(this.body) + this.offset;
			left += offset;
		}
		var top = pos[1] + getHeight(this.title);

		setStyle(this.body, 'left', left + 'px');
		setStyle(this.body, 'top', top + 'px');
		setStyle(this.body, 'visibility', 'visible');
		setStyle(this.body, 'opacity', this.opacity);
		setStyle(this.body, 'MozOpacity', this.opacity);
		setStyle(this.body, 'KhtmlOpacity', this.opacity);
		setStyle(this.body, 'filter', 'alpha(opacity=' + this.opacity * 100 + ')');

		if(this.tid) {
			clearTimeout(this.tid);
		}
		this.tid = setInterval(bind(this, this.appear), 30);
	},

	deactivate: function(){
		if(this.tid) {
			clearTimeout(this.tid);
		}
		this.tid = setInterval(bind(this, this.fade), 30);
	},

	appear: function() {
		this.opacity += 0.1;
		if(this.opacity >= this.maxopacity) {
			this.opacity = this.maxopacity;
			clearTimeout(this.tid);
		}
		setStyle(this.body, 'opacity', this.opacity);
		setStyle(this.body, 'MozOpacity', this.opacity);
		setStyle(this.body, 'KhtmlOpacity', this.opacity);
		setStyle(this.body, 'filter', 'alpha(opacity=' + this.opacity * 100 + ')');
	},

	fade:function() {
		this.opacity -= 0.1;
		if(this.opacity <= 0) {
			this.opacity = 0;
			setStyle(this.body, 'visibility', 'hidden');
			clearTimeout(this.tid);
		}
		setStyle(this.body, 'opacity', this.opacity);
		setStyle(this.body, 'MozOpacity', this.opacity);
		setStyle(this.body, 'KhtmlOpacity', this.opacity);
		setStyle(this.body, 'filter', 'alpha(opacity=' + this.opacity * 100 + ')');
	}
}

$ = function(id) {
	return document.getElementById(id);
}