// ==UserScript==
// @name          Facebook desktop notification
// @namespace     https://www.schtobia.de/
// @version       0.0.6
// @description	  Facebook desktop notification (based on HTML5)
// @include       http*://www.facebook.com/*
// @include       http*://facebook.com/*
// @grant         GM_getValue
// @run-at        document-end
// @downloadURL   https://github.com/schtobia/greasemonkey/raw/master/facebook-notification.user.js
// @updateURL     https://github.com/schtobia/greasemonkey/raw/master/facebook-notification.user.js
// @resource  FacebookLogo https://s-static.ak.facebook.com/rsrc.php/yi/r/q9U99v3_saj.ico
// ==/UserScript==
//

var Notification = window.Notification || window.mozNotification || window.webkitNotification;

var friendRequestsElement = document.getElementById("requestsCountValue");
var messagesElement = document.getElementById("mercurymessagesCountValue");
var notificationsElement = document.getElementById("notificationsCountValue");
var newFriendRequests = 0;
var newMessages = 0;
var newNotifications = 0;

var lastFriendRequests = 0;
var lastMessages = 0;
var lastNotifications = 0;
var notificationInstance = null;

var timeout = GM_getValue("timeout", 30000);

notify = function()
{
	newFriendRequests = friendRequestsElement.innerHTML;
	newMessages = messagesElement.innerHTML;
	newNotifications = notificationsElement.innerHTML;

	if (newFriendRequests > lastFriendRequests || newMessages > lastMessages || newNotifications > lastNotifications )
	{
		var msg= " ";

		if (newFriendRequests > lastFriendRequests)
			msg=msg+"| "+(newFriendRequests-lastFriendRequests)+" new Friend Request(s) |";

		if (newMessages>lastMessages)
			msg=msg+"| "+(newMessages-lastMessages)+" new Message(s) |";

		if (newNotifications>lastNotifications)
			msg=msg+"| "+(newNotifications-lastNotifications)+" new Notification(s) |";

		notificationInstance = new Notification("Facebook (" + newFriendRequests + '|' + newMessages + '|' + newNotifications + ')',
			{
				"dir" : "auto",
				"body" : msg,
				"icon" : GM_getResourceURL("FacebookLogo"),
			}
		)

		lastFriendRequests = newFriendRequests;
		lastMessages = newMessages;
		lastNotifications = newNotifications;
	}
}

registerNotification = function()
{
	var registrationSuccessful = false;
	Notification.requestPermission(function(grantedPermission){
		if (grantedPermission === "granted")
		{
			registrationSuccessful = true;
			console.log("permission granted");
		}
		else
		{
			registrationSuccessful = false;
			console.log("permission NOT granted");
		}
	});

	if (registrationSuccessful)
		setTimeout(notify, timeout);
}

/* Normal flow of operations below! */
if (!Notification)
{
	alert("Notifications are not supported for this browser version yet.");
}
else
	registerNotification();