addLoadListener(init);

function init()
{
//  var optional = document.getElementById("druglist");
//optional.className = "disabled";

  var onoff = document.getElementById("type1");
  onoff.onchange = showOptional;
  changeDisplay(onoff);
  onoff = document.getElementById("type2");
  onoff.onchange = showOptional;

  return true;
}

function showOptional(e)
{
  var el;
  if (window.event && window.event.srcElement)
	el = window.event.srcElement;
  if (e && e.target)
	el = e.target;
  if (!el) return;
  changeDisplay(el);
  return true;
}

function changeDisplay(el)
{
  var optional = document.getElementById("druglist");
  var ta = document.getElementById("comments");
  var all_boxes = document.getElementsByTagName('input');
  if (el.value == "Repeat") {
	optional.className = "";
    ta.value = "Please issue a repeat prescription for the drugs listed below:";
  }
  else {
	optional.className = "disabled";
	ta.value = "";
  }
  for (var i = 0; i < all_boxes.length; i++) {
	if (all_boxes[i].className == "drug" || all_boxes[i].className == "dose" )
	  all_boxes[i].disabled = optional.className;
  }

  return true;
}

function addLoadListener(fn)
{
  if (typeof window.addEventListener != 'undefined')
  {
    window.addEventListener('load', fn, false);
  }
  else if (typeof document.addEventListener != 'undefined')
  {
    document.addEventListener('load', fn, false);
  }
  else if (typeof window.attachEvent != 'undefined')
  {
    window.attachEvent('onload', fn);
  }
  else
  {
    var oldfn = window.onload;
    if (typeof window.onload != 'function')
    {
      window.onload = fn;
    }
    else
    {
      window.onload = function()
      {
        oldfn();
        fn();
      };
    }
  }
}