function calculateDay(getal)
{
    var f = document.forms['form'];
    
    var month = f.elements['MD' + getal].selectedIndex;
    month = f.elements['MD' + getal].options[month].value.substring(0,2);

    var maandje = new Array();
    maandje[1]="January";
    maandje[2]="February";
    maandje[3]="March";
    maandje[4]="April";
    maandje[5]="May";
    maandje[6]="June";
    maandje[7]="July";
    maandje[8]="August";
    maandje[9]="September";
    maandje[10]="October";
    maandje[11]="November";
    maandje[12]="December";
    
    var month = maandje[eval(month)];
    
    day = f.elements['DD' + getal].options[f.elements['DD' + getal].selectedIndex].text;
    year = f.elements['MD' + getal].value.substring(2,6);
    
    var oyear=year
    
    var dob = " "+ year +", "+month + ",  "+day;
    var thenx = new Date(dob);
    
    var year=thenx.getYear();
    if (year<100) year="19" + thenx.getYear();
    else year=thenx.getYear();
    
    if (year > 1969) wyear=year;
    else {
    if (oyear<1900) {
    if (oyear>1800) {
    wrelyear= (eval(oyear)-1801)%(28);
    wyear = wrelyear+1981;
    }
    else wyear = 1970 
    }
    else
    if (oyear>1900) {wrelyear= (eval(oyear)-1901)%(28); 
    wyear= wrelyear+1985
    }
    else 
    if (oyear==1900) {wyear= 1990;
       }              
    }
    var dob = " "+ wyear +", "+month + ",  "+day;
    var thenx = new Date(dob);
    
    var theday = thenx.getDay()+1;
    var date=thenx.getDate();
    
    var weekday = new Array(6);
    weekday[1]="Zo";
    weekday[2]="Ma";
    weekday[3]="Di";
    weekday[4]="Wo";
    weekday[5]="Do";
    weekday[6]="Vr";
    weekday[7]="Za";
    
    day = weekday[theday];
    f.elements['weekdag' + getal].value = day;
}

var syncChange = true;
function sync_datumpulldown() 
{
   var f = document.forms['form'];

   if ((syncChange == true) || (f.elements['MD2'].options.selectedIndex < f.elements['MD1'].options.selectedIndex))
       f.elements['MD2'].options.selectedIndex = f.elements['MD1'].options.selectedIndex;

    sync_dagpulldown1();
}

function sync_datumpulldown2()
{
    var f = document.forms['form'];
    syncChange = false;
    
    if (f.elements['MD1'].options.selectedIndex > f.elements['MD2'].options.selectedIndex)
        f.elements['MD1'].options.selectedIndex = f.elements['MD2'].options.selectedIndex;
    
    sync_dagpulldown1();
}

function sync_dagpulldown1()
{
    var f = document.forms['form'];
    
    if ((f.elements['MD1'].options.selectedIndex) == (f.elements['MD2'].options.selectedIndex))
    {
    if (f.elements['DD1'].options.selectedIndex > f.elements['DD2'].options.selectedIndex)
        f.elements['DD2'].options.selectedIndex = f.elements['DD1'].options.selectedIndex;
    }
}

function sync_dagpulldown2()
{
    var f = document.forms['form'];
    
    if ((f.elements['MD1'].options.selectedIndex) == (f.elements['MD2'].options.selectedIndex))
    {
    if (f.elements['DD2'].options.selectedIndex < f.elements['DD1'].options.selectedIndex)
        f.elements['DD1'].options.selectedIndex = f.elements['DD2'].options.selectedIndex;
    }
}

function MM_swapImgRestore() { //v2.0
  if (document.MM_swapImgData != null)
    for (var i=0; i<(document.MM_swapImgData.length-1); i+=2)
      document.MM_swapImgData[i].src = document.MM_swapImgData[i+1];
}

function MM_preloadImages() { //v2.0
  /*
  if (document.images) {
    var imgFiles = MM_preloadImages.arguments;
    if (document.preloadArray==null) document.preloadArray = new Array();
    var i = document.preloadArray.length;
    with (document) for (var j=0; j<imgFiles.length; j++) if (imgFiles[j].charAt(0)!="#"){
      preloadArray[i] = new Image;
      preloadArray[i++].src = imgFiles[j];
  } }
  */
}

function MM_swapImage() { //v2.0
  var i,j=0,objStr,obj,swapArray=new Array,oldArray=document.MM_swapImgData;
  for (i=0; i < (MM_swapImage.arguments.length-2); i+=3) {
    objStr = MM_swapImage.arguments[(navigator.appName == 'Netscape')?i:i+1];
    if ((objStr.indexOf('document.layers[')==0 && document.layers==null) ||
        (objStr.indexOf('document.all[')   ==0 && document.all   ==null))
      objStr = 'document'+objStr.substring(objStr.lastIndexOf('.'),objStr.length);
    obj = eval(objStr);
    if (obj != null) {
      swapArray[j++] = obj;
      swapArray[j++] = (oldArray==null || oldArray[j-1]!=obj)?obj.src:oldArray[j];
      obj.src = MM_swapImage.arguments[i+2];
  } }
  document.MM_swapImgData = swapArray; //used for restore
}

function CBcheck(form,checkbox)
{
  if(checkbox.checked == true) { form.submit() } else { alert("Geef svp aan of u de wijzigings- en annuleringsvoorwaarden hebt geraadpleegd.") }
}

function CBbeo(form,BEO,checkbox)
{
    var i,ec=false;

    if (form.BEO)
    {
        if (BEO.type=="hidden")
        {
            if (BEO.value != "")
            {
                ec=true
            }
        }
        else
        {
            for (i=0; i<BEO.length; i++)
            {
                ec=ec || BEO[i].checked
            }
        }

        if (ec==false)
        {
            alert("Geef svp aan van welke ticketingoptie u gebruik wilt maken.")
        }
        else
        {
            if(checkbox.checked == true)
            {
                form.submit()
            }else{
                alert("Geef svp aan of u de wijzigings- en annuleringsvoorwaarden hebt geraadpleegd.")
            }
        }
    }
}

function MM_checkPlugin(plugin, theURL, altURL, IEGoesToURL) { //v2.0
  if ((navigator.plugins && navigator.plugins[plugin]) || //if NS, or
      (IEGoesToURL &&  //if flag set, and MSIE browser for Win95/NT (ActiveX)
       navigator.appName.indexOf('Microsoft') != -1 &&
       navigator.appVersion.indexOf('Mac') == -1 &&
       navigator.appVersion.indexOf('3.1') == -1)) {
    if (theURL.length>2) window.location = theURL;
  } else {
    if (altURL.length>2) window.location = altURL;
  }
  document.MM_returnValue = false;
}

function MM_goToURL() { //v1.0
  for (var i=0; i< (MM_goToURL.arguments.length - 1); i+=2) //with arg pairs
    eval(MM_goToURL.arguments[i]+".location='"+MM_goToURL.arguments[i+1]+"'");
  document.MM_returnValue = false;
}

function MM_openBrWindow(theURL,winName,features) { //v2.0
  window.open(theURL,winName,features);
}


function gotoURL(dropDown) {
URL=dropDown.options[dropDown.selectedIndex].value
  if(URL.length>0)
	self.location.href=URL;
}



function HotelRBcheck(form)
{ var i,test=false;
  if (form.HRID.length==null)
    { test=true } else
    { for (i=0; i<form.HRID.length; i++) { test=test || form.HRID[i].checked }; };
  if(test==true) { form.submit() } else { alert("Selecteer een kamer!") }
}

function checkPassVisa(form)
{
  if ((form.Int.value==0) ||
      (   ((form.PC[0].checked==true) || (form.PC[1].checked==true) || (form.PC[2].checked==true))
       && ((form.VC[0].checked==true) || (form.VC[1].checked==true) || (form.VC[2].checked==true)) ))
       { form.submit() }
  else { alert("U dient hier te bevestigen dat u voldoet aan de paspoort en visa vorwaarden voor de door u geboekte bestemmingen") }
}

function checkPassVisaSubmit(form)
{
  if ((form.Int.value==0) ||
      (   ((form.PC[0].checked==true) || (form.PC[1].checked==true) || (form.PC[2].checked==true))
       && ((form.VC[0].checked==true) || (form.VC[1].checked==true) || (form.VC[2].checked==true)) ))
       { return true; }
  else { alert("U dient hier te bevestigen dat u voldoet aan de paspoort en visa vorwaarden voor de door u geboekte bestemmingen"); return false; }
}

function post(form) 
{ 
 if (form.state.value == "0")
 { form.submit(); form.state.value=1; } else
 { alert("Uw verzoek wordt momenteel verwerkt..  Even geduld alstublieft"); }
}

function CheckForm(form) 
{ 
 if (form.state.value == "0")
 { form.state.value=1; return true; } else
 { alert("Uw verzoek wordt momenteel verwerkt..  Even geduld alstublieft"); return false; }
}

function preload_IMG(imgname,dbgmode)
{
	try {
		plaatjes.length=plaatjes.length+1		
	} catch(e) {
		plaatjes = new Array()
	}
	plaatje=new Image()
	plaatje.src=imgname
	if (dbgmode) {
		// Document.write if for debugging purpose only
		document.write("<pre>Preloaded "+imgname+" in cache #"+plaatjes.length+"</pre>")
	}
}

// vertrek vanuit en terug naar invullen onload + onblur aanpassen van bestemming en terug vanuit
function copy_alles()
{
    f = document.forms['form']
    f.CA2.value = f.CD1.value;
    f.CD2.value = f.CA1.value;
}