var currentState = null;

function $(id) {
	return document.getElementById(id);
}

function init() {
	var states = $("states");

	for (var i = 0; i < STATES.length; i++) {
		var state = STATES[i];
		states.options[states.options.length] = new Option(state.name, state.id);
	}

	states.selectedIndex = 0;
	clearLocations();
	updateArrow();
}

function updateRadio() {
	var doLocations = $("feedbackLocation").checked;
	$("states").disabled = !doLocations;
	$("locations").disabled = !doLocations;
	updateArrow();
}

function updateLocations() {
	var states = $("states");
	var state = states.options[states.selectedIndex].value;
	if (currentState == state) return;
	clearLocations();
	var locations = $("locations");

	for (var i = 0; i < LOCATIONS.length; i++) {
		var location = LOCATIONS[i];

		if (location.state == state) {
			locations.options[locations.options.length] = new Option(location.name, location.offerCode);
		}
	}

	if (state != null) locations.selectedIndex = 0;
	locations.style.display = state != null ? "block" : "none";
	var currentState = state;
	updateArrow();
}

function clearLocations() {
	var locations = $("locations");

	while (locations.options.length > 1) {
		locations.options[1] = null;
	}
}

function updateArrow() {

	if (canGo())
	{
		$("nextImage").src = "next.gif";
		$("nextImage").style.cursor = "pointer";
	}
	else
	{
		$("nextImage").src = "next-disabled.gif";
		$("nextImage").style.cursor = "default";
	}


}

function go() {
	if (!canGo()) return;
	var offerCode = null;

	if ($("feedbackLocation").checked) {
		var locations = $("locations");
		offerCode = locations.options[locations.selectedIndex].value;
	} else {
		offerCode = CORPORATE_OFFER_CODE;
	}

	location.href = "http://www.mshare.net/websurvey/app?gateway=jasonsdelicfm&offercode=" + offerCode;
}

function canGo() {
	var doLocations = $("feedbackLocation").checked;
	return doLocations ? $("locations").selectedIndex > 0 : true;
}