function createRequestObject() {
    var ro;
    var browser = navigator.appName;
    if(browser == "Microsoft Internet Explorer"){
        ro = new ActiveXObject("Microsoft.XMLHTTP");
    }else{
        ro = new XMLHttpRequest();
    }
    return ro;
}

var attendanceReq;
var responseName;

function attendanceRequest(scenename, numscenes, name) {

    attendanceReq = createRequestObject();
    attendanceReq.open('post', 'ajax/');
    attendanceReq.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
	responseName = name;
    if (numscenes > 0)
    {
		var scene = '';
		for(var i = 1; i <= numscenes; i++)
		{
			var obj = document.getElementById(scenename+''+i);
			scene += obj.options[obj.selectedIndex].value + ((i==numscenes)?'':',');
		}
    	attendanceReq.onreadystatechange = attendanceResponse;
		attendanceReq.send('subaction=attendance&scenes='+scene);
	}
}


function attendanceResponse() {

    if(attendanceReq.readyState == 4)
	{	 
	
		//alert(attendanceReq.responseText); //alert results
		var actors = attendanceReq.responseXML.getElementsByTagName('actors');
	
		colA = document.getElementById(responseName+'_colA_selector');
		for(var c = 0; c < colA.length; c++)
			if((colA.options[c].text).charAt(0) == '*')
				colA.options[c].text = (colA.options[c].text).substr(2);
		colB = document.getElementById(responseName+'_colB_selector');
		for(var c = 0; c < colB.length; c++)
			if((colB.options[c].text).charAt(0) == '*')
				colB.options[c].text = (colB.options[c].text).substr(2);
		
		if (actors.length != 0)
		{
			//mark responses
			for (var i=0; i < actors.length; i++)
			{
				for (var c = 0; c < colA.length; c++)
					if(colA.options[c].value == actors[i].firstChild.nodeValue)
						colA.options[c].text = '* '+colA.options[c].text;
				for (var c = 0; c < colB.length; c++)
					if(colB.options[c].value == actors[i].firstChild.nodeValue)
						colB.options[c].text = '* '+colB.options[c].text;
			}
		}
    }
}