// fajl AsyncExample.js
function initPage() {
   var oHTML = new AsyncClass("async-html.html","html","id_html");
   var oText = new AsyncClass("async-text.txt","text","id_text");
   var oXML = new AsyncClass("async-xml.php","xml","id_xml");
}

function AsyncClass(sAddress,sResponseType,idMenu) {
   var thisObj = this;
   var buttonSet=false;
   var content = null;
   var rType = sResponseType;
   init(sAddress,idMenu);

   function init(sAddress) {
      oOption = document.getElementById(idMenu);
      attachEventHandler(oOption, "click", handleClick, false);
      content=document.createTextNode("Ucitava se...");
      startAsync(sAddress,loadingComplete);
   }

   function loadingComplete(oAsync) {
      if (asyncComplete(oAsync)) {
         if (rType=='text') {
            content=document.createTextNode(oAsync.responseText);
         } else if (rType=='html') {
            content = document.createElement("div");
            content.innerHTML=oAsync.responseText;
         } else {
            parseXML(oAsync.responseXML);
         }
      }
   }

   function parseXML(oXML) {
      var aPersons = oXML.getElementsByTagName("osoba");
      content = document.createElement("ul");
      for (i=0; i<aPersons.length; i++) {
         oPerson = aPersons[i];
         var sPerson = getXMLTagValue("ime",oPerson)+", ";
         sPerson += getXMLTagValue("staz",oPerson)+" godina staža, ";
         sPerson += getXMLTagValue("odmor",oPerson)+" dana odmora";
         var oTextNode = document.createTextNode(sPerson);
         var oListItem = document.createElement("li");
         oListItem.appendChild(oTextNode);
         content.appendChild(oListItem);
      }
   }

   function getXMLTagValue(sTagName,oXML) {
      var oTag = oXML.getElementsByTagName(sTagName)[0];
      var oTextNode = oTag.firstChild;
      var sNodeText = oTextNode.nodeValue;
      return sNodeText;
   }

   function handleClick() {
      oPanel = document.getElementById("id_main_panel");
      oPanel.removeChild(oPanel.firstChild);
      oPanel.appendChild(content);
      if (rType=="html" && !buttonSet) {
         var oButton = document.getElementById("id_sabirac");
         attachEventHandler(oButton, "click", submitNumbers, false);
      }
   }

   function submitNumbers() {
      var a = document.getElementById("id_prvi_sabirak").value;
      var b = document.getElementById("id_drugi_sabirak").value;
      var sURL = "adder.php?a="+a+"&b="+b;
      startAsync(sURL,addingComplete);
   }

   function addingComplete(oAsync) {
      if (asyncComplete(oAsync)) {
         alert(oAsync.responseText);
      }
   }
}