GDNetMenuDown.spacerGif = "images/x.gif"; 
GDNetMenuDown.dingbatOn = "images/expand_1.gif"; 
GDNetMenuDown.dingbatOff = "images/expand_1.gif"; 
GDNetMenuDown.dingbatSize = 14; 
GDNetMenuDown.menuPadding = 1; 
GDNetMenuDown.itemPadding = 4; 
GDNetMenuDown.shadowSize = 2; 
GDNetMenuDown.shadowOffset = 3; 
GDNetMenuDown.itemColor = "#FFFFFF"; //菜单文字颜色
GDNetMenuDown.shadowColor = "#FFFFFF"; //阴影颜色
GDNetMenuDown.backgroundColor = "#000000"; 
GDNetMenuDown.hideDelay = 800; //隐藏菜单延时时间
GDNetMenuDown.slideTime = 200; 


GDNetMenuDown.reference = {topLeft:1,topRight:2,bottomLeft:3,bottomRight:4};
GDNetMenuDown.direction = {down:1,right:2};
GDNetMenuDown.registry = [];
GDNetMenuDown._maxZ = 100;




GDNetMenuDown.isSupported = function() {
	if (typeof GDNetMenuDown.isSupported.r == "boolean") 
	return GDNetMenuDown.isSupported.r;
	var ua = navigator.userAgent.toLowerCase();
	var an = navigator.appName;
	var r = false;
	if (ua.indexOf("gecko") > -1)
		r = true; 
	else if (an == "Microsoft Internet Explorer")
	{
		if (document.getElementById) r = true; 
	}
	GDNetMenuDown.isSupported.r = r;
	return r;
}

GDNetMenuDown.initialize = function() {
	for (var i = 0, menu = null; menu = this.registry[i]; i++) {
	menu.initialize();
	}
}

GDNetMenuDown.renderAll = function() {
	var aMenuHtml = [];
	for (var i = 0, menu = null; menu = this.registry[i]; i++)
	{
		aMenuHtml[i] = menu.toString();
	}
	document.write(aMenuHtml.join(""));
}

function GDNetMenuDown(oActuator, iDirection, iLeft, iTop, iReferencePoint, parentMenuSet) {

	this.addItem = addItem;
	this.addMenu = addMenu;
	this.toString = toString;
	this.initialize = initialize;
	this.isOpen = false;
	this.show = show;
	this.hide = hide;
	this.items = [];

	this.onactivate = new Function(); 
	this.ondeactivate = new Function(); 
	this.onmouseover = new Function(); 
	this.onqueue = new Function(); 

	this.index = GDNetMenuDown.registry.length;
	GDNetMenuDown.registry[this.index] = this;
	var id = "GDNetMenuDown" + this.index;
	var contentHeight = null;
	var contentWidth = null;
	var childMenuSet = null;
	var animating = false;
	var childMenus = [];
	var slideAccel = -1;
	var elmCache = null;
	var ready = false;
	var _this = this;
	var a = null;
	var pos = iDirection == GDNetMenuDown.direction.down ? "top" : "left";
	var dim = null;

	function addItem(sText, sUrl) {
		var item = new GDNetMenuDownItem(sText, sUrl, this);
		item._index = this.items.length;
		this.items[item._index] = item;
	}
	function addMenu(oMenuItem) {
		if (!oMenuItem.parentMenu == this) throw new Error("Cannot add a menu here");
		if (childMenuSet == null) childMenuSet = new GDNetMenuDownSet(GDNetMenuDown.direction.right, -5, 2, GDNetMenuDown.reference.topRight);
		var m = childMenuSet.addMenu(oMenuItem);
		childMenus[oMenuItem._index] = m;
		m.onmouseover = child_mouseover;
		m.ondeactivate = child_deactivate;
		m.onqueue = child_queue;
		return m;
	}
	function initialize() {
		initCache();
		initEvents();
		initSize();
		ready = true;
	}
	function show() {

		if (ready) {
			_this.isOpen = true;
			animating = true;
			setContainerPos();
			elmCache["clip"].style.visibility = "visible";
			elmCache["clip"].style.zIndex = GDNetMenuDown._maxZ++;
			slideStart();
			_this.onactivate();
		}
	}
	function hide() {
		if (ready) {
			_this.isOpen = false;
			animating = true;
			for (var i = 0, item = null; item = elmCache.item[i]; i++) 
			{
				dehighlight(item);
			}
			if (childMenuSet) childMenuSet.hide();
			slideStart();
			_this.ondeactivate();
		}
	}
	function setContainerPos() {
		var sub = oActuator.constructor == GDNetMenuDownItem; 
		var act = sub ? oActuator.parentMenu.elmCache["item"][oActuator._index] : oActuator; 
		var el = act;
		var x = 0;
		var y = 0;
		var minX = 0;
		var maxX = (window.innerWidth ? window.innerWidth : document.body.clientWidth) - parseInt(elmCache["clip"].style.width);
		var minY = 0;
		var maxY = (window.innerHeight ? window.innerHeight : document.body.clientHeight) - parseInt(elmCache["clip"].style.height);

		while (sub ? el.parentNode.className.indexOf("GDNetMenuDownMenu") == -1 : el.offsetParent) {
			x += el.offsetLeft;
			y += el.offsetTop;
			if (el.scrollLeft) x -= el.scrollLeft;
			if (el.scrollTop) y -= el.scrollTop;
			el = el.offsetParent;
		}
		if (oActuator.constructor == GDNetMenuDownItem) {
			x += parseInt(el.parentNode.style.left);
			y += parseInt(el.parentNode.style.top);
		}
		switch (iReferencePoint) {
			case GDNetMenuDown.reference.topLeft:
				break;
			case GDNetMenuDown.reference.topRight:
				x += act.offsetWidth;
				break;
			case GDNetMenuDown.reference.bottomLeft:
				y += act.offsetHeight;
				break;
			case GDNetMenuDown.reference.bottomRight:
				x += act.offsetWidth;
				y += act.offsetHeight;
			break;
		}
		x += iLeft;
		y += iTop;
		x = Math.max(Math.min(x, maxX), minX);
		y = Math.max(Math.min(y, maxY), minY);
		elmCache["clip"].style.left = x + "px";
		elmCache["clip"].style.top = y + "px";
	}
	function slideStart() {
		var x0 = parseInt(elmCache["content"].style[pos]);
		var x1 = _this.isOpen ? 0 : -dim;
		if (a != null) a.stop();
		a = new Accelimation(x0, x1, GDNetMenuDown.slideTime, slideAccel);
		a.onframe = slideFrame;
		a.onend = slideEnd;
		a.start();
	}
	function slideFrame(x) {
		elmCache["content"].style[pos] = x + "px";
	}
	function slideEnd() {
		if (!_this.isOpen) elmCache["clip"].style.visibility = "hidden";
		animating = false;
	}
	function initSize() {

		var ow = elmCache["items"].offsetWidth;
		var oh = elmCache["items"].offsetHeight;
		var ua = navigator.userAgent.toLowerCase();

		elmCache["clip"].style.width = ow + GDNetMenuDown.shadowSize + 2 + "px";
		elmCache["clip"].style.height = oh + GDNetMenuDown.shadowSize + 2 + "px";

		elmCache["content"].style.width = ow + GDNetMenuDown.shadowSize + "px";
		elmCache["content"].style.height = oh + GDNetMenuDown.shadowSize + "px";
		contentHeight = oh + GDNetMenuDown.shadowSize;
		contentWidth = ow + GDNetMenuDown.shadowSize;
		dim = iDirection == GDNetMenuDown.direction.down ? contentHeight : contentWidth;

		elmCache["content"].style[pos] = -dim - GDNetMenuDown.shadowSize + "px";
		elmCache["clip"].style.visibility = "hidden";

		if (ua.indexOf("mac") == -1 || ua.indexOf("gecko") > -1) {

			elmCache["background"].style.width = ow + "px";
			elmCache["background"].style.height = oh + "px";
			elmCache["background"].style.backgroundColor = GDNetMenuDown.backgroundColor;

			elmCache["shadowRight"].style.left = ow + "px";
			elmCache["shadowRight"].style.height = oh - (GDNetMenuDown.shadowOffset - GDNetMenuDown.shadowSize) + "px";
			elmCache["shadowRight"].style.backgroundColor = GDNetMenuDown.shadowColor;



			elmCache["shadowBottom"].style.top = oh + "px";
			elmCache["shadowBottom"].style.width = ow - GDNetMenuDown.shadowOffset + "px";
			elmCache["shadowBottom"].style.backgroundColor = GDNetMenuDown.shadowColor;
		}
		else
		{

			elmCache["background"].firstChild.src = GDNetMenuDown.backgroundPng;
			elmCache["background"].firstChild.width = ow;
			elmCache["background"].firstChild.height = oh;

			elmCache["shadowRight"].firstChild.src = GDNetMenuDown.shadowPng;
			elmCache["shadowRight"].style.left = ow + "px";
			elmCache["shadowRight"].firstChild.width = GDNetMenuDown.shadowSize;
			elmCache["shadowRight"].firstChild.height = oh - (GDNetMenuDown.shadowOffset - GDNetMenuDown.shadowSize);



			elmCache["shadowBottom"].firstChild.src = GDNetMenuDown.shadowPng;
			elmCache["shadowBottom"].style.top = oh + "px";
			elmCache["shadowBottom"].firstChild.height = GDNetMenuDown.shadowSize;
			elmCache["shadowBottom"].firstChild.width = ow - GDNetMenuDown.shadowOffset;
		}
	}
	function initCache() {
		var menu = document.getElementById(id);
		var all = menu.all ? menu.all : menu.getElementsByTagName("*"); 
		elmCache = {};
		elmCache["clip"] = menu;
		elmCache["item"] = [];
		for (var i = 0, elm = null; elm = all[i]; i++) {
			switch (elm.className) {
				case "items":
				case "content":
				case "background":
				case "shadowRight":
				case "shadowBottom":
					elmCache[elm.className] = elm;
					break;
				case "item":
					elm._index = elmCache["item"].length;
					elmCache["item"][elm._index] = elm;
					break;
			}
		}

		_this.elmCache = elmCache;
	}
	function initEvents() {

		for (var i = 0, item = null; item = elmCache.item[i]; i++) {
			item.onmouseover = item_mouseover;
			item.onmouseout = item_mouseout;
			item.onclick = item_click;
		}

		if (typeof oActuator.tagName != "undefined") {
			oActuator.onmouseover = actuator_mouseover;
			oActuator.onmouseout = actuator_mouseout;
		}

		elmCache["content"].onmouseover = content_mouseover;
		elmCache["content"].onmouseout = content_mouseout;
	}
	function highlight(oRow) {
		oRow.className = "item hover";
		if (childMenus[oRow._index]) 
		oRow.lastChild.firstChild.src = GDNetMenuDown.dingbatOn;
	}
	function dehighlight(oRow) {
		oRow.className = "item";
		if (childMenus[oRow._index]) 
		oRow.lastChild.firstChild.src = GDNetMenuDown.dingbatOff;
	}
	function item_mouseover() {
		if (!animating) {
			highlight(this);
			if (childMenus[this._index]) 
				childMenuSet.showMenu(childMenus[this._index]);
			else if (childMenuSet) childMenuSet.hide();
		}
	}
	function item_mouseout() {
		if (!animating) {
			if (childMenus[this._index])
			childMenuSet.hideMenu(childMenus[this._index]);
			else 
			dehighlight(this);
		}
	}
	function item_click() {
		if (!animating) {
			if (_this.items[this._index].url) 
			location.href = _this.items[this._index].url;
		}
	}
	function actuator_mouseover() {
		parentMenuSet.showMenu(_this);
	}
	function actuator_mouseout() {
		parentMenuSet.hideMenu(_this);
	}
	function content_mouseover() {
		if (!animating) {
			parentMenuSet.showMenu(_this);
			_this.onmouseover();
		}
	}
	function content_mouseout() {
		if (!animating) {
			parentMenuSet.hideMenu(_this);
		}
	}
	function child_mouseover() {
		if (!animating) {
			parentMenuSet.showMenu(_this);
		}
	}
	function child_deactivate() {
		for (var i = 0; i < childMenus.length; i++) {
			if (childMenus[i] == this) {
			dehighlight(elmCache["item"][i]);
			break;
		}
	}
	}
	function child_queue() {
		parentMenuSet.hideMenu(_this);
	}
	function toString() {
		var aHtml = [];
		var sClassName = "GDNetMenuDownMenu" + (oActuator.constructor != GDNetMenuDownItem ? " top" : "");
		for (var i = 0, item = null; item = this.items[i]; i++) {
			aHtml[i] = item.toString(childMenus[i]);
		}
		return '<div id="' + id + '" class="' + sClassName + '">' + 
		'<div class="content"><table class="items" cellpadding="0" cellspacing="0" border="0">' +
		'<tr><td><img src="' + GDNetMenuDown.spacerGif + '" width="0" height="'
		+ GDNetMenuDown.menuPadding + '"></td></tr>' + 
		aHtml.join('') + 
		'<tr><td><img src="' + GDNetMenuDown.spacerGif + '" width="0" height="'
		+ GDNetMenuDown.menuPadding + '"></td></tr></table>' + 
		'<div class="shadowBottom"><img src="' + GDNetMenuDown.spacerGif + '" width="1" height="1"></div>' + 
		'<div class="shadowRight"><img src="' + GDNetMenuDown.spacerGif + '" width="1" height="1"></div>' + 
		'<div class="background"><img src="' + GDNetMenuDown.spacerGif + '" width="1" height="1"></div>' + 
		'</div></div>';
		}
	}

	GDNetMenuDownSet.registry = [];
	function GDNetMenuDownSet(iDirection, iLeft, iTop, iReferencePoint) {

	this.addMenu = addMenu;
	this.showMenu = showMenu;
	this.hideMenu = hideMenu;
	this.hide = hide;

	var menus = [];
	var _this = this;
	var current = null;
	this.index = GDNetMenuDownSet.registry.length;
	GDNetMenuDownSet.registry[this.index] = this;

	function addMenu(oActuator) {
	var m = new GDNetMenuDown(oActuator, iDirection, iLeft, iTop, iReferencePoint, this);
	menus[menus.length] = m;
	return m;
	}
	function showMenu(oMenu) {
	if (oMenu != current) {

	if (current != null) hide(current); 

	current = oMenu;

	oMenu.show();
	}
	else {

	cancelHide(oMenu);
	}
	}
	function hideMenu(oMenu) {

	if (current == oMenu && oMenu.isOpen) {

	if (!oMenu.hideTimer) scheduleHide(oMenu);
	}
	}
	function scheduleHide(oMenu) {

	oMenu.onqueue();
	oMenu.hideTimer = window.setTimeout("GDNetMenuDownSet.registry[" + _this.index + "].hide(GDNetMenuDown.registry[" + oMenu.index + "])", GDNetMenuDown.hideDelay);
	}
	function cancelHide(oMenu) {

	if (oMenu.hideTimer) {
	window.clearTimeout(oMenu.hideTimer);
	oMenu.hideTimer = null;
	}
	}
	function hide(oMenu) { 
	if (!oMenu && current) oMenu = current;
	if (oMenu && current == oMenu && oMenu.isOpen) {

	cancelHide(oMenu);
	current = null;
	oMenu.hideTimer = null;
	oMenu.hide();
	}
	}
	}

	function GDNetMenuDownItem(sText, sUrl, oParent) {
	this.toString = toString;
	this.text = sText;
	this.url = sUrl;
	this.parentMenu = oParent;
	function toString(bDingbat) {
	var sDingbat = bDingbat ? GDNetMenuDown.dingbatOff : GDNetMenuDown.spacerGif;
	var iEdgePadding = GDNetMenuDown.itemPadding + GDNetMenuDown.menuPadding;
	var sPaddingLeft = "color:" + GDNetMenuDown.itemColor  + ";padding:" + GDNetMenuDown.itemPadding + "px; padding-left:" + iEdgePadding + "px;"
	var sPaddingRight = "padding:" + GDNetMenuDown.itemPadding + "px; padding-right:" + iEdgePadding + "px;"
	return '<tr class="item"><td nowrap style="' + sPaddingLeft + '">' + 
	sText + '</td><td width="14" style="' + sPaddingRight + '">' + 
	'<img src="' + sDingbat + '" width="14" height="14"></td></tr>';
	}
}

function Accelimation(from, to, time, zip) {
	if (typeof zip == "undefined") zip = 0;
	if (typeof unit == "undefined") unit = "px";
	this.x0 = from;
	this.x1 = to;
	this.dt = time;
	this.zip = -zip;
	this.unit = unit;
	this.timer = null;
	this.onend = new Function();
	this.onframe = new Function();
}

Accelimation.prototype.start = function() {
	this.t0 = new Date().getTime();
	this.t1 = this.t0 + this.dt;
	var dx = this.x1 - this.x0;
	this.c1 = this.x0 + ((1 + this.zip) * dx / 3);
	this.c2 = this.x0 + ((2 + this.zip) * dx / 3);
	Accelimation._add(this);
}

Accelimation.prototype.stop = function() {
	Accelimation._remove(this);
}

Accelimation.prototype._paint = function(time) {
	if (time < this.t1) {
	var elapsed = time - this.t0;
	this.onframe(Accelimation._getBezier(elapsed/this.dt,this.x0,this.x1,this.c1,this.c2));
	}
	else this._end();
}

Accelimation.prototype._end = function() {
	Accelimation._remove(this);
	this.onframe(this.x1);
	this.onend();
}

Accelimation._add = function(o) {
	var index = this.instances.length;
	this.instances[index] = o;

	if (this.instances.length == 1) {
		this.timerID = window.setInterval("Accelimation._paintAll()", this.targetRes);
	}
}

Accelimation._remove = function(o) {
	for (var i = 0; i < this.instances.length; i++) {
	if (o == this.instances[i]) {
	this.instances = this.instances.slice(0,i).concat( this.instances.slice(i+1) );
	break;
	}
}

if (this.instances.length == 0) {
	window.clearInterval(this.timerID);
	this.timerID = null;
	}
}

Accelimation._paintAll = function() {
	var now = new Date().getTime();
	for (var i = 0; i < this.instances.length; i++) {
	this.instances[i]._paint(now);
	}
}

Accelimation._B1 = function(t) { return t*t*t }
Accelimation._B2 = function(t) { return 3*t*t*(1-t) }
Accelimation._B3 = function(t) { return 3*t*(1-t)*(1-t) }
Accelimation._B4 = function(t) { return (1-t)*(1-t)*(1-t) }

Accelimation._getBezier = function(percent,startPos,endPos,control1,control2) {
	return endPos * this._B1(percent) + control2 * this._B2(percent) + control1 * this._B3(percent) + startPos * this._B4(percent);
}

Accelimation.instances = [];
Accelimation.targetRes = 10;
Accelimation.timerID = null;


function init() {
	if (GDNetMenuDown.isSupported()) {
		GDNetMenuDown.initialize();
	}
}

