/// <reference path="vsdoc/airports-vsdoc.js" />
var targetUrl = LANG_ROOT_PATH + 'AJAX/CountryAirports.aspx';
var xmlApts = GetXmlRequestObject();
var targetDropDown = null;

var getElement = function (id) { return (document.all ? document.all[id] : document.getElementById(id)); }

// gets a reference to the xml request object
function GetXmlRequestObject(){
	var obj = null;
	if(window.XMLHttpRequest){
		obj = new XMLHttpRequest();
	}
	else if(window.ActiveXObject){
		try{ obj = new ActiveXObject('Msxml2.XMLHTTP'); }
		catch(e){
			try{ obj = new ActiveXObject('Microsoft.XMLHTTP'); }
			catch(oc){ obj = null; }
		}
	}
	return obj;
}

function AddCountryAirport(name, iata)
{
	if(targetDropDown){
		var newOpt = new Option(name, iata);
		targetDropDown.options[targetDropDown.options.length] = newOpt;
		targetDropDown.disabled = false;
	}
}

// make a request to the server
function FetchAirports(elemId, country){
	if(xmlApts && xmlApts.readyState != 0)
		xmlApts.abort();

	targetDropDown = getElement(elemId);

	if(targetDropDown && xmlApts){
		while(targetDropDown.options.length > 0)
			targetDropDown.remove(0);

		targetDropDown.options[0] = new Option(LOADING_TEXT, '');
		updateList(targetDropDown);
		setDisabled(targetDropDown, true);

		var pg = targetUrl;
		pg += '?country=' + encodeURIComponent(country);
		
		xmlApts.open('GET', pg, true);
		xmlApts.onreadystatechange = function(){
			try{
				if(xmlApts.readyState == 4){
					while(targetDropDown.options.length > 0)
						targetDropDown.remove(0);

					try{ targetDropDown.options[0] = new Option(TXT_SELECT_AIRPORT, ''); } catch(ex){}
					
					if(xmlApts.responseText){ eval(xmlApts.responseText); }
					if(targetDropDown){ setDisabled(targetDropDown, false); }
					updateList(targetDropDown);
				}
			}
			catch(ex){}
		};
		xmlApts.send(null);
	}
}

function setDisabled(ctl, val){
	if(ctl){
		if(ctl.setDisabled){ ctl.setDisabled(val)}
		else if(ctl.disabled != null){ ctl.disabled = val; }
	}
}

function updateList(ctl){
	if(ctl && ctl.updateList){ ctl.updateList(); }
}