// 定義常量
GDNetMenuDown.spacerGif = "../images/x.gif"; 
GDNetMenuDown.dingbatOn = "../images/expand-1.gif"; 
GDNetMenuDown.dingbatOff = "../images/expand-0.gif"; 
GDNetMenuDown.dingbatSize = 14; 
GDNetMenuDown.menuPadding = 1; 
GDNetMenuDown.itemPadding = 1; 
GDNetMenuDown.itemClass = "itemContent"; 
GDNetMenuDown.shadowSize = 2; 
GDNetMenuDown.shadowOffset = 3; 
GDNetMenuDown.shadowColor = "#eee"; 
//GDNetMenuDown.backgroundColor = "#f8f8f8"; 
GDNetMenuDown.hideDelay = 1000; 
GDNetMenuDown.slideTime = 200; 
GDNetMenuDown.reference = {topLeft:1,topRight:2,bottomLeft:3,bottomRight:4};
GDNetMenuDown.direction = {down:1,right:2};
GDNetMenuDown.registry = [];
GDNetMenuDown._maxZ = 100;

//判斷瀏覽器是否支持
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();
  }
  
   var shtml=aMenuHtml.join("");
    document.write(shtml);
    
}

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 frameID = "framemask";
  this.layerID = id;
  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(oLinks) {
    for(i=0;i<oLinks.length;i++){
      var item = new GDNetMenuDownItem(oLinks[i].text, oLinks[i].href, 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, 0, -1, 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;
    if(!(navigator.userAgent.toLowerCase().indexOf("msie")>0)){
      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]);
  }
//  alert(aHtml.join(''));
  
  return '<div id="' + id + '" class="' + sClassName + '">' + 
    '<div class="content"><table class="items" cellpadding="0" cellspacing="0" border="0">' + 
    '<tr><td colspan="2"><img src="' + GDNetMenuDown.spacerGif + '" width="1" height="' + GDNetMenuDown.menuPadding + '"></td></tr>' + 
    aHtml.join('') + 
    '<tr><td colspan="2"><img src="' + GDNetMenuDown.spacerGif + '" width="1" 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 = "padding:" + GDNetMenuDown.itemPadding + "px; padding-left:" + iEdgePadding + "px;"
    var sPaddingRight = "padding:" + GDNetMenuDown.itemPadding + "px; padding-right:" + iEdgePadding + "px;"
    return '<tr class="item"><td nowrap class="'+ GDNetMenuDown.itemClass + '" style="' + sPaddingLeft + '">' + sText + '</td><td style="' + sPaddingRight + '"><img src="' + sDingbat + '" width="8" height="14"></td></tr>';
  }
}

function Accelimation(from, to, time, zip) {
  //alert(from);
  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;