Add WS Connection object

www/scripts/common/websockets/connection.js

@@ -1,36 +1,71 @@
 define([
-    "underscore"
-], function (_) {
-    return function (options) {
-        if (!"url" in options) {
-            throw "You must set the websocket 'url'"
-        }
-        if (!"topic" in options) {
-            throw "You must set the websocket 'topic'"
-        }
-        if (!"eventAggregator" in options) {
-            throw "You must set an event aggregator"
-        }
+    "underscore",
+    "backbone"
+], function (_, Backbone) {
+    var instance;
 
-        var eventAggregator = options.eventAggregator;
+    function init(url) {
+        var activeSession = null;
 
-        return {
-            run: function() {
+        return _.extend({
+            connect: function() {
+                if (this.hasSession()) {
+                    return;
+                }
+                var $this = this;
                 // autobahn js is defined as a global object there is no way to load
                 // it as a UMD module
-                ab.connect(options.url, function (session) {
-                    eventAggregator.trigger("ws:connect", session);
-                    session.subscribe(options.topic, function (topic, msg) {
-                            // double encoded string
-                            var msg = JSON.parse(JSON.parse(msg));
-                            eventAggregator.trigger("ws:"+msg.event, msg, session);
-                        }
-                    );
+                ab.connect(url, function (session) {
+                    $this.setSession(session);
+                    $this.trigger("ws:connect", activeSession);
                 },
                 function (code, reason) {
-                    eventAggregator.trigger("ws:session-gone", code,reason);
+                    $this.trigger("ws:session-gone", code, reason);
                 });
+            },
+            close: function() {
+                if (false === this.hasSession()) {
+                    return;
+                }
+                this.getSession().close();
+                this.setSession(null);
+                this.trigger("ws:session-close");
+            },
+            hasSession: function() {
+                return this.getSession() !== null;
+            },
+            getSession: function() {
+                return activeSession;
+            },
+            setSession: function(session) {
+                activeSession = session;
+            },
+            subscribe: function(topic, callback) {
+                if (false === this.hasSession()) {
+                    this.on("ws:connect", function(session) {
+                        session.subscribe(topic, callback);
+                    });
+                    return;
+                }
+                this.getSession().subscribe(topic, callback);
+                this.trigger("ws:session-subscribe", topic);
+            },
+            unsubscribe: function(topic, callback) {
+                if (false === this.hasSession()) {
+                    return;
+                }
+                this.getSession().unsubscribe(topic, callback);
+                this.trigger("ws:session-unsubscribe", topic);
             }
-        }
+        }, Backbone.Events);
     }
+
+    return {
+        getInstance: function(url) {
+            if (!instance) {
+                instance = init(url);
+            }
+            return instance;
+        }
+    };
 });