1 files changed, 78 insertions, 0 deletions
diff --git a/catalog-ui/app/scripts/services/event-listener-service.ts b/catalog-ui/app/scripts/services/event-listener-service.ts
new file mode 100644
index 0000000000..67afd65c56
--- /dev/null
+++ b/catalog-ui/app/scripts/services/event-listener-service.ts
@@ -0,0 +1,78 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+/**
+ * Created by obarda on 7/4/2016.
+ */
+/// <reference path="../references"/>
+module Sdc.Services {
+
+    'use strict';
+
+    interface IEventListenerService {
+
+    }
+
+    interface ICallbackData {
+        callback:Function;
+        args:any[];
+    }
+
+    export class EventListenerService implements IEventListenerService {
+
+        public observerCallbacks:Utils.Dictionary<string, ICallbackData[]> = new Utils.Dictionary<string, Array<ICallbackData>>();
+
+        //register an observer + callback
+        public registerObserverCallback = (eventName:string, callback:Function, ...args) => {
+            let callbackData = {
+                callback: callback,
+                args: args
+            }
+
+            if (this.observerCallbacks.containsKey(eventName)) {
+                let callbacks = this.observerCallbacks.getValue(eventName);
+
+                // Only insert the callback if the callback is different from existing callbacks.
+                for (let i = 0; i < callbacks.length; i++) {
+                    if (callbacks[i].toString() === callback.toString()) {
+                        return; // Do not add this callback.
+                    }
+                }
+
+                callbacks.push(callbackData);
+                this.observerCallbacks.setValue(eventName, callbacks);
+            } else {
+                this.observerCallbacks.setValue(eventName, [callbackData]);
+            }
+        };
+
+        //unregister an observer
+        public unRegisterObserver = (eventName:string) => {
+            if (this.observerCallbacks.containsKey(eventName)) {
+                this.observerCallbacks.remove(eventName);
+            }
+        };
+
+        public notifyObservers = function (eventName:string, ...args) {
+            _.forEach(this.observerCallbacks.getValue(eventName), (callbackData:ICallbackData) => {
+                callbackData.callback(...args);
+            });
+        };
+    }
+}