/*************************************************************************
  This code is from Dynamic Web Coding at http://www.dyn-web.com/
  Copyright 2001-3 by Sharon Paine 
  See Terms of Use at http://www.dyn-web.com/bus/terms.html
  regarding conditions under which you may use this code.
  This notice must be retained in the code as is!
*************************************************************************/

// resize fix for ns4
var origWidth, origHeight;
if (document.layers) {
	origWidth = window.innerWidth; origHeight = window.innerHeight;
	window.onresize = function() { if (window.innerWidth != origWidth || window.innerHeight != origHeight) history.go(0); }
}

var cur_lyr;	// holds id of currently visible layer
function swapLayers(id) {
  if (cur_lyr) hideLayer(cur_lyr);
  showLayer(id);
  cur_lyr = id;
}

function showLayer(id) {
  var lyr = getElemRefs(id);
  if (lyr && lyr.css) lyr.css.visibility = "visible";
}

function hideLayer(id) {
  var lyr = getElemRefs(id);
  if (lyr && lyr.css) lyr.css.visibility = "hidden";
}

function getElemRefs(id) {
	var el = (document.getElementById)? document.getElementById(id): (document.all)? document.all[id]: (document.layers)? getLyrRef(id,document): null;
	if (el) el.css = (el.style)? el.style: el;
	return el;
}

// get reference to nested layer for ns4
// from old dhtmllib.js by Mike Hall of www.brainjar.com
function getLyrRef(lyr,doc) {
	if (document.layers) {
		var theLyr;
		for (var i=0; i<doc.layers.length; i++) {
	  	theLyr = doc.layers[i];
			if (theLyr.name == lyr) return theLyr;
			else if (theLyr.document.layers.length > 0) 
	    	if ((theLyr = getLyrRef(lyr,theLyr.document)) != null)
					return theLyr;
	  }
		return null;
  }
}

// preloading
function MM_preloadImages() { //v3.0
 var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
   var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
   if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

// pop-up
function popup(url) {
 fenster=window.open(url, "popupwindow", "width=570,height=300,resizable=yes");
 fenster.focus();
 return false;
}


// function switchDiv()
//  this function takes the id of a div
//  and calls the other functions required
//  to show that div
//
function switchDiv(div_id)
{
  var style_sheet = getStyleObject(div_id);
  if (style_sheet)
  {
    hideAll();
    changeObjectVisibility(div_id,"visible");
  }
  else 
  {
    alert("sorry, this only works in browsers that do Dynamic HTML");
  }
}

// function hideAll()
//  hides a bunch of divs
//
function hideAll()
{
   changeObjectVisibility("sendbyyou","hidden");
   changeObjectVisibility("sendbyus","hidden");
}

// function getStyleObject(string) -> returns style object
//  given a string containing the id of an object
//  the function returns the stylesheet of that object
//  or false if it can't find a stylesheet.  Handles
//  cross-browser compatibility issues.
//
function getStyleObject(objectId) {
  // checkW3C DOM, then MSIE 4, then NN 4.
  //
  if(document.getElementById && document.getElementById(objectId)) {
	return document.getElementById(objectId).style;
   }
   else if (document.all && document.all(objectId)) {  
	return document.all(objectId).style;
   } 
   else if (document.layers && document.layers[objectId]) { 
	return document.layers[objectId];
   } else {
	return false;
   }
}

function changeObjectVisibility(objectId, newVisibility) {
    // first get a reference to the cross-browser style object 
    // and make sure the object exists
    var styleObject = getStyleObject(objectId);
    if(styleObject) {
	styleObject.visibility = newVisibility;
	return true;
    } else {
	// we couldn't find the object, so we can't change its visibility
	return false;
    }
}