var xmlHttp;

function addInstrument(str)
{
    document.getElementById("instrumentslisting").innerHTML="<img src='images/ajax-loader.gif'>";
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=add&class=instrument";
    url=url+"&instrument_id="+str;
    xmlHttp.onreadystatechange=instrumentsUpdated; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function remInstrument(str)
{
    document.getElementById("instrumentslisting").innerHTML="<img src='images/ajax-loader.gif'>";
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=rem&class=instrument";
    url=url+"&instrument_id="+str;
    xmlHttp.onreadystatechange=instrumentsUpdated; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function addGenre(str)
{
    document.getElementById("genreslisting").innerHTML="<img src='images/ajax-loader.gif'>";
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=add&class=genre";
    url=url+"&genre_id="+str;
    xmlHttp.onreadystatechange=genreUpdated; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function remGenre(str)
{
    document.getElementById("genreslisting").innerHTML="<img src='images/ajax-loader.gif'>";
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=rem&class=genre";
    url=url+"&genre_id="+str;
    xmlHttp.onreadystatechange=genreUpdated; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function addBandmember(user_id,band_id)
{
    document.getElementById("bandmembers").innerHTML="<img src='images/ajax-loader.gif'>";
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=add&class=bandmember";
    url=url+"&user_id="+user_id;
    url=url+"&band_id="+band_id;
    xmlHttp.onreadystatechange=bandmemberAdded; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function setManager(user_id,band_id)
{
    document.getElementById("bandmembers").innerHTML="<img src='images/ajax-loader.gif'>";
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=manager&class=bandmember";
    url=url+"&user_id="+user_id;
    url=url+"&band_id="+band_id;
    xmlHttp.onreadystatechange=bandmemberAdded; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function remBandmember(user_id,band_id)
{
    document.getElementById("bandmembers").innerHTML="<img src='images/ajax-loader.gif'>";                           
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=rem&class=bandmember";
    url=url+"&user_id="+user_id;
    url=url+"&band_id="+band_id;
    xmlHttp.onreadystatechange=bandmemberAdded; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function searchMembers(str, band_id)
{
    if( str == "" )
        return;
    document.getElementById("searchmembers").innerHTML="<img src='images/ajax-loader.gif'>";
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=searchbandmembers&class=users";
    url=url+"&value="+str;
    url=url+"&band_id="+band_id;
    xmlHttp.onreadystatechange=searchedMembers; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function remGenre(str)
{
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
        alert ("Browser does not support HTTP Request");
        return;
     }
    var url="ajaxcontroller.php";
    url=url+"?action=rem&class=genre";
    url=url+"&genre_id="+str;
    xmlHttp.onreadystatechange=genreUpdated; 
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null); 
}

function instrumentsUpdated() 
{ 
    if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
     { 
        document.getElementById("instrumentslisting").innerHTML=xmlHttp.responseText; 
     } 
}

function genreUpdated() 
{ 
    if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
     { 
        document.getElementById("genrelisting").innerHTML=xmlHttp.responseText; 
     } 
}

function bandmemberAdded() 
{ 
    if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
     { 
        document.getElementById("bandmembers").innerHTML=xmlHttp.responseText; 
     } 
}

function searchedMembers() 
{ 
    if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
     {   
        document.getElementById("searchmembers").innerHTML=xmlHttp.responseText; 
     } 
}

function GetXmlHttpObject()
{
    var xmlHttp=null;
    try
     {
     // Firefox, Opera 8.0+, Safari
        xmlHttp=new XMLHttpRequest();
     }
    catch (e)
     {
     //Internet Explorer
     try
      {
        xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
      }
     catch (e)
      {
        xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
      }
     }
    return xmlHttp;
}