var Images    = new Array();
var ImagesOn  = new Array();
var ImagesOvr = new Array();

var menuItemOn = null;

function PNGFix(oImage) {
   var ret = false;
   if(oImage.tagName) {
     var tagName = oImage.tagName.toLowerCase();
     if(tagName == "div") ret = true;
   }
   return ret;
}

function menuHiLite(oImage, key) {
   if(PNGFix(oImage)) {
     var src = oImage.imageOvr;
     oImage.runtimeStyle.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + src + "')";//,sizingMethod='scale')";
   } else {
      var newImage = ImagesOvr[key];
      if(newImage.complete) {
        oImage.src = newImage.src;
      }
   }
}

function menuUnHiLite(oImage, key) {
  if(PNGFix(oImage)) {
    var src = oImage.image;
    oImage.runtimeStyle.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + src + "')";//,sizingMethod='scale')";
  } else {
    var newImage = Images[key];
    if(menuItemOn == oImage) {
      newImage = ImagesOn[key];
    }
    if(newImage) {
     oImage.src = newImage.src;
    }
  }  
}

function menuOn(oImage, key) {
  var newImage = ImagesOn[key];
  if(newImage) {
   oImage.src = newImage.src;
  }
}

function menuPreloadImages(imagesLocation) {
  for(key in Images) {
    var img     = new Image();
    img.src     = imagesLocation + "/" + Images[key];
    Images[key] = img;
  }
  for(key in ImagesOn) {
    var img     = new Image();
    img.src     = imagesLocation + "/" + ImagesOn[key];
    ImagesOn[key] = img;
  }
  for(key in ImagesOvr) {
    var img     = new Image();
    img.src     = imagesLocation + "/" + ImagesOvr[key];
    ImagesOvr[key] = img;
  }
}

function menuClick(url, menuObject) {
  var urlParamOk     = (typeof(url)        == "string");
  var menuObjParamOk = (typeof(menuObject) == "object");

  if(typeof(sid) == "undefined") sid = "";
  
  var menuId = "";
  if(menuObjParamOk) {
    if(menuObject.id) menuId = menuObject.id;
  }
  var fullUrl = url;
  if(fullUrl.indexOf('?') != -1) fullUrl += "&sid=" + sid + "&menuId=" + menuId;
  else fullUrl += "?sid=" + sid + "&menuId=" + menuId;
  document.location.assign(fullUrl);
}