function checkCijfer(elmn) {
  if (parseInt(elmn.value) >= 1.0 && parseInt(elmn.value) <= 10.0) {
    elmn.value = number_format(elmn.value, 1);
  } else {
    if (elmn.value.length > 0) {
      elmn.style.backgroundColor = '#FF6666';
    }

    elmn.value = '';
  }
}

var voorkeur_checked = 0;

function voorkeur(elm) {
  if (elm) {
    var cb = document.getElementsByTagName('input');

    // set Disabled
    for (i=0; i < cb.length; i++) {
      if (elm.id == 'voorkeurswerkzaamheden1') {
        if (cb[i].id == 'voorkeurswerkzaamheden2' && cb[i].type == 'radio') {
          if (cb[i].value == elm.value) {
            cb[i].disabled = true;
          } else {
            cb[i].disabled = false;
          }
        }
      } else {
        if (cb[i].id == 'voorkeurswerkzaamheden1' && cb[i].type == 'radio') {
          if (cb[i].value == elm.value && elm.value != 'geen') {
            cb[i].disabled = true;
          } else {
            cb[i].disabled = false;
          }
        }
      }
    }
  }
}

function isDate(dateStr) {
  var datePat = /^(\d{1,2})(\/|-)(\d{1,2})(\/|-)(\d{4})$/;
  var matchArray = dateStr.match(datePat); // is the format ok?

  if (matchArray == null) {
    return false;
  }

  day = parseInt(matchArray[1]); // p@rse date into variables
  month = parseInt(matchArray[3]);
  year = parseInt(matchArray[5]);

  if (month < 1 || month > 12) { // check month range
    alert("Maand moet een getal tussen de 1 en de 12 zijn.");
    return false;
  }

  if (day < 1 || day > 31) {
    alert("Dag moet een getal tussen de 1 en de 31 zijn.");
    return false;
  }

  if ((month==4 || month==6 || month==9 || month==11) && day==31) {
    alert("Month "+month+" doesn`t have 31 days!");
    return false;
  }

  if (month == 2) { // check for february 29th
    var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
    if (day > 29 || (day == 29 && !isleap)) {
      alert("Februari heeft in " + year + " geen " + day + " dagen!");
      return false;
    }
  }

  return true;
}

function checkLeeftijd() {
  var yr  = parseInt(document.getElementById('geb_j').value);
  var day = parseInt(document.getElementById('geb_d').value);
  var mon = parseInt(document.getElementById('geb_m').value);

  if (day && mon && yr) {
    if (isDate(day + '/' + mon + '/' + yr)) {
      var one_year = 1000 * 60 * 60 * 24 * 30 * 12;
      var pastdate = new Date(yr, mon-1, day);

      today = new Date();

      finalunit = one_year;
      decimals = 0;

      yearspast = today.getFullYear() - yr -1;
      tail = (today.getMonth() > mon -1 || today.getMonth() == mon -1 && today.getDate() >= day)? 1 : 0;
      pastdate.setFullYear(today.getFullYear());
      pastdate2 = new Date(today.getFullYear() -1, mon -1, day);
      tail = (tail == 1)? tail+Math.floor((today.getTime() - pastdate.getTime()) / (finalunit)*decimals) / decimals : Math.floor((today.getTime()- pastdate2.getTime()) / (finalunit) * decimals) / decimals;

      if (yearspast >= 16) {


        return true;
      } else {
        return false;
      }
    }
  }
}

function positionImg(loaded) {
  if (parseInt(navigator.appVersion)>3) {
    if (navigator.appName == "Netscape") {
      winH = window.innerHeight;
    }

    if (navigator.appName.indexOf("Microsoft") != -1) {
      winH = document.body.offsetHeight;
    }
  }

  var docH = document.getElementById('topper').offsetTop;

  if (docH < winH) {
    docH = winH;
  }

  var debug = document.getElementById('debug');

  var img_holder = document.getElementById('big_image_holder');
  var img = document.getElementById('big_image');

  if (loaded) {
    img_holder.style.marginLeft = '500px';
    img_holder.style.visibility = 'visible';
  }

  var img_height = img.height;

  var scroll = 0;

  if (typeof(window.pageYOffset) == 'number') {
    scroll = window.pageYOffset;
  } else if (document.body && (document.body.scrollLeft || document.body.scrollTop)) {
    scroll = document.body.scrollTop;
  }  else if (document.documentElement && (document.documentElement.scrollLeft || document.documentElement.scrollTop)) {
    scroll = document.documentElement.scrollTop;
  }

  if (img && img_holder) {
    margin = scroll + (winH - img_height);

    if ((margin + img_height) > docH) {
      margin = docH - img_height;
    }

    if (margin < 40) {
      margin = 40;
    }

    img_holder.style.marginTop = margin +'px';

    if (loaded) {
      sIFR.replace(helvetica_BI, {
        selector: 'h3',
        wmode: 'transparent',
        css: { '.sIFR-root': { 'font-style': 'italic', 'font-weight': 'normal', 'font-size': '18px', 'color': '#FFFFFF', 'text-align': 'center' }}
      });
    }
  }
}

window.onresize = function() { positionImg() };
window.onscroll = function() { positionImg() };
window.onload   = function() { positionImg(true) };