var request;

function NewHTTP() {
    request=null;
    try {
        return new XMLHttpRequest();
    } 
    catch (e) {
        try {
            return new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch(e) {
            return new ActiveXObject('Microsoft.XMLHTTP');
        }
    }
}



function getDiscussionItems(objectid) {
    document.getElementById("discussiontab").style.backgroundImage='url(images/whitetab.jpg)';
    document.getElementById("discussiontab").style.color='#000000';
    document.getElementById("commenttab").style.backgroundImage='url(images/nonactivetab.jpg)';
    document.getElementById("commenttab").style.color='#FFFFFF';
    
    var url = thisdomain + "ajax/php/discussion.php?action=getitems&objectid=" + objectid;

    request = NewHTTP();
    if (request == null) alert('kan geen verbinding maken');
    request.open("GET",url,true);
    request.onreadystatechange = OnGetDiscussionItems;
    request.send(null);

}


function OnGetDiscussionItems() {
    var extratext = document.getElementById("extratext");
    extratext.innerHTML = '';
    
    if (request.readyState==4) {
        if (request.status==200) {
            if (request.responseXML != null  ) {
                var discussiontext = '';
                
                var xmlDoc = request.responseXML;
                var noi = xmlDoc.documentElement.getElementsByTagName("numberofitems");
                var numberofitems = noi[0].firstChild.nodeValue;
               
                if (numberofitems > 0) {
                    var items= xmlDoc.documentElement.getElementsByTagName("item");
                    //discussiontext += '<ul>';
                    var ul = document.createElement("ul");
                    var newlist = extratext.appendChild(ul);

                    for (i=0;i<items.length;i++) {
                        var disc = items[i].getElementsByTagName("itemtext");
                        var disctext = disc[0].firstChild.nodeValue;
                        var owner = items[i].getElementsByTagName("itemowner");
                        var ownertext = owner[0].firstChild.nodeValue;
                        var date = items[i].getElementsByTagName("itemdate");
                        var datetext = date[0].firstChild.nodeValue;
                        
                        var newitem = document.createElement("li");
                        var newitemtext = newlist.appendChild(newitem);
                        
                        var thetext = disctext + '<br/>geplaatst door ' + ownertext + ' op ' + datetext;
                        newitemtext.innerHTML = thetext;
                        
                    }
                }
                else {
                    var p = document.createElement("p");
                    var thepar = extratext.appendChild(p);
                    thepar.innerHTML = "Er zijn nog geen discussie-items gepost voor dit object";
                }
                
                
                var userid = document.getElementById("userid").innerHTML;
                userid = userid.replace(/^\s+/,''); 
		userid = userid.replace(/\s+$/,'');

                var form_objectid;
                if (document.getElementById("objectid").value != null) {
                    form_objectid = document.getElementById("objectid").value;
                }
                else {
                    form_objectid = document.getElementById("objectid").innerHTML;
                }
                
                if (userid != '-') { //i.e. the user is logged in
                    //probeer dit ook via appendchild
                    discussiontext += '<form name="adddiscussionitem" id="adddiscussionitem">';
                    discussiontext += '<input type="hidden" name="disc_objectid" id="disc_objectid" value="' + form_objectid + '" />';
                    discussiontext += '<input type="hidden" name="userid" id="userid" value="' + userid + '" />';
                    discussiontext += '<textarea name="newitem" id="newitem" rows="3" cols="20">';
                    discussiontext += '</textarea>';
                    discussiontext += '<input type="button" name="additem" id="additem" value="Voeg toe" onclick="addDiscussionItem(\'' + form_objectid + '\')" />';
                    discussiontext += '</form>';
                    
                }
                extratext.innerHTML += discussiontext;
            }
            else {
                extratext.innerHTML = 'helaas werkt de discussiefunctie op dit moment niet'; 
            }
        }
        else {
            extratext.innerHTML = 'helaas werkt de discussiefunctie op dit moment niet'; 
        }
    }
}



function addDiscussionItem() {
    var url = thisdomain + "ajax/php/discussion.php";
    var params = "action=additem";

    var addform = document.forms['adddiscussionitem'];
    var disc_objectid = addform.disc_objectid.value;
    //var disc_objectid = document.getElementById("objectid").innerHTML;
    var userid = addform.userid.value;
    var itemtext = addform.newitem.value;
    
    params += "&objectid=" + disc_objectid + "&userid=" + userid + "&itemtext=" + itemtext;

    request = NewHTTP();
    if (request == null) alert('kan geen verbinding maken');
    request.open("POST",url,true);
    request.onreadystatechange = OnAddDiscussionItem;
    request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
    request.send(params);
}


function OnAddDiscussionItem() {
    var extratext = document.getElementById("extratext");

    if (request.readyState==4) {
        if (request.status==200) {
            if (request.responseXML != null  ) {
                var xmlDoc = request.responseXML;
                var objid = xmlDoc.documentElement.getElementsByTagName("objectid");
                var objectid = objid[0].firstChild.nodeValue;
                getDiscussionItems(objectid);
            }
            else {
                extratext.innerHTML = 'helaas werkt de discussiefunctie op dit moment niet'; 
            }
        }
        else {
            extratext.innerHTML = 'helaas werkt de discussiefunctie op dit moment niet'; 
        }
    }

}