ONLOAD_STACK = [];

function preloadImage( url ) {
  img = new Image;
  img.src = url;
}

function popupOpen(link, width, height) {
    window.open(link.href, "", "width=" + width + ",height=" + height + ",scrollbars=yes,menubar=no" );
    return false;
}

function goTo(url, override) {
    if (override) {
        window.location.replace(url);
    } else {
        window.location = url;
    }
}
function changeImage( id, url ) {
    document.getElementById( id ).src = url;
    return false;
}

function registerOnLoad(callback) {
    // old browsers doesn't support Array#push
    ONLOAD_STACK[ONLOAD_STACK.length] = callback;
}

function onLoadCallback() {
    var len = ONLOAD_STACK.length;
    for (var i = 0; i < len; i++) {
        ONLOAD_STACK[i]();
    }
}
function obj( id ) {
  return document.getElementById( id );
}

function removeObj( id ) {
  ob = document.getElementById( id );
  ob.parentNode.removeChild( ob );
}

function prepareTextInput( input, def_value ) {
  if ( input.value == def_value ) input.value = "";
}

function divBlink( delay, mdiv) {
  if ( mdiv.style.visibility == 'hidden' ) {
    mdiv.style.visibility = 'visible';
  } else {
    mdiv.style.visibility = 'hidden';
  }
  
  setTimeout("divBlink("+delay+",document.getElementById('"+mdiv.id+"'))", delay );

  return false;
}

function cssBlink( delay, mdiv, newClass ) {
  oldClass = mdiv.className;
  mdiv.className = newClass;
  setTimeout("cssBlink("+delay+",document.getElementById('"+mdiv.id+"'),'"+oldClass+"')", delay );

  return false;
}