var global_yr, global_mon;

function getDefaultCalendar () {
	var url = "calendar.php";
	returnContent (url, "calendar");
	var dt = new Date();
	global_yr = dt.getFullYear();
	global_mon = dt.getMonth() + 1;
}

function getCalendar (yr, mon) {

	global_yr = yr;
	global_mon = mon;

	var url = "calendar.php?yr=" + yr + "&mon=" + mon;
	returnContent (url, "calendar");
	document.getElementById("general").style.display = "block";
	document.getElementById("catalog").style.display = "none";
	document.getElementById("course").style.display = "none";
	document.getElementById("calendar").style.display = "block";
}

/*
* displayContent
* data: returned HTML from the "includes" directory
* dest: the DIV's ID where it is to be stored
*
* This determines where the returned data should be displayed
*/
function displayContent (data, dest) {
	var destination = document.getElementById(dest);

	destination.innerHTML = data;

	var mainContent = dojo.byId("mainContent").innerHTML; //always want the main content
	var appState = new ApplicationState(mainContent, "mainContent", true);
	appState.showStateData();
	dojo.back.addToHistory(appState);

}

/*
* returnContent
* url: the url called to get the data
* dest: the DIV's ID where returned data is to be stored
*
* Uses the DOJO Toolkit for XMLHTTP calls.
*/
function returnContent (url, dest) {

	dojo.xhrGet ({
		//url: url + "&dest=" + dest,
		url: url,
		handleAs: "text",
		handle: function(data, args) {
			displayContent (data, dest);
			dojo.parser.parse(dojo.byId(dest));
		},
		error: function(err) {
			alert("Error retrieving page. Please try again!");
		},
		timeout: 5000
	});
}

function displayType (type) {
	// had to include workaround for IE in this function, since it doesn't work correctly on the getElementsByName.
	// http://bytes.com/forum/thread707075.html
	// http://www.dreamincode.net/code/snippet293.htm
	
	//getCalendar (global_yr, global_mon);
	document.getElementById("calendar").style.display = "block";
	document.getElementById("catalog").style.display = "none";
	document.getElementById("general").style.display = "block";
	document.getElementById("course").style.display = "none";

	var courses = document.getElementsByTagName("div");

	if (type == 0) {
		for (i = 0; i < courses.length; i++) {
			if (courses[i].getAttribute("name") == "course")
				courses[i].style.display = "block";
		}
	}

	if (type > 0) {
		for (i = 0; i < courses.length; i++) {
			if (courses[i].getAttribute("name") == "course") {
				if (courses[i].id.split(":")[0] == type)
					courses[i].style.display = "block";
				else
					courses[i].style.display = "none";
			}
		}
	}

/*	this works for firefox, but not IE

	if (type > 0) {
		for (i = 0; i < courses.length; i++) {
			if (courses[i].id.split(":")[0] == type)
				courses[i].style.display = "block";
			else
				courses[i].style.display = "none";
		}
	}*/
}

function returnCourse (course_schedule_id, yr, mon) {

	global_yr = yr;
	global_mon = mon;

	var url = "course_schedule.php?course_schedule_id=" + course_schedule_id + "&yr=" + yr + "&mon=" + mon;
	returnContent (url, "course");
	document.getElementById("general").style.display = "none";
	document.getElementById("catalog").style.display = "none";
	document.getElementById("calendar").style.display = "none";
	document.getElementById("course").style.display = "block";
}

function displayCatalog (course_type_id) {

	var url = "course_catalog.php?course_type_id=" + course_type_id + "&yr=" + global_yr + "&mon=" + global_mon;
	returnContent (url, "catalog");
	document.getElementById("general").style.display = "none";
	document.getElementById("calendar").style.display = "none";
	document.getElementById("course").style.display = "none";
	document.getElementById("catalog").style.display = "block";
}

function submitWaitlist (frm) {
	var course_schedule_id = frm.course_schedule_id.value;
	var name = frm.name.value;
	var email = frm.email.value;
	var url = "student_add_delete.php?action=waitlist&course_schedule_id=" + course_schedule_id + "&name=" + name + "&email=" + email;
	returnContent (url, "waitlistresult");
	frm.reset();
	return false;
}

function enableRegister () {
	var btn = document.getElementById("registerButton");
	btn.disabled = false;
}