var inputSubmit = null;

function initialize()
{
    initializeSearchForm();
}

function addNewEvent(obj, type, fn)
{
   if (obj.addEventListener)
   {
      obj.addEventListener(type, fn, false);
   }
   else if (obj.attachEvent)
   {
      obj["e" + type + fn] = fn;
      obj[type + fn] = function() { obj["e" + type + fn](window.event); }
      obj.attachEvent("on" + type, obj[type + fn]);
   }
}

function updateSearchFormStatus(input)
{
	if (this.value.length == 0)
	{
	    inputSubmit.setAttribute("disabled", "disabled");
	}
	else
	{
	    inputSubmit.removeAttribute("disabled");
	}
}

function initializeSearchForm()
{
	var suchformular = document.getElementById('suchformular');
	var divs = suchformular.getElementsByTagName('div');

	if (divs.length != 1)
	    return;

	var inputs = divs[0].getElementsByTagName('input');

    addNewEvent(inputs[0], 'keyup', updateSearchFormStatus);

	inputSubmit = inputs[1];
	inputSubmit.setAttribute("disabled", "disabled");
}