1 files changed, 126 insertions, 0 deletions
diff --git a/src/base-pubsub.ts b/src/base-pubsub.ts
new file mode 100644
index 0000000..36b959a
--- /dev/null
+++ b/src/base-pubsub.ts
@@ -0,0 +1,126 @@
+declare const window: Window;
+
+export class BasePubSub {
+
+    subscribers: Map<string, ISubscriber>;
+    eventsCallbacks: Function[];
+    clientId: string;
+    eventsToWait: Map<string, string[]>;
+    lastEventNotified: string;
+
+    constructor(pluginId: string) {
+        this.subscribers = new Map<string, ISubscriber>();
+        this.eventsCallbacks = [];
+        this.eventsToWait = new Map<string, string[]>();
+        this.clientId = pluginId;
+        this.lastEventNotified = '';
+        this.onMessage = this.onMessage.bind(this);
+
+        window.addEventListener('message', this.onMessage);
+    }
+
+    public register(subscriberId: string, subscriberWindow: Window, subscriberUrl: string) {
+        const subscriber = {
+            window: subscriberWindow,
+            locationUrl: subscriberUrl || subscriberWindow.location.href
+        } as ISubscriber;
+
+        this.subscribers.set(subscriberId, subscriber);
+    }
+
+    public unregister(subscriberId: string) {
+        this.subscribers.delete(subscriberId);
+    }
+
+    public on(callback: Function) {
+        const functionExists = this.eventsCallbacks.find((func: Function) => {
+            return callback.toString() === func.toString();
+        });
+
+        if (!functionExists) {
+            this.eventsCallbacks.push(callback);
+        }
+    }
+
+    public off(callback: Function) {
+        const index = this.eventsCallbacks.indexOf(callback);
+        this.eventsCallbacks.splice(index, 1);
+    }
+
+    public notify(eventType: string, eventData?: any) {
+        const eventObj = {
+            type: eventType,
+            data: eventData,
+            originId: this.clientId
+        } as IPubSubEvent;
+
+        this.subscribers.forEach( (subscriber: ISubscriber, subscriberId: string) => {
+            subscriber.window.postMessage(eventObj, subscriber.locationUrl);
+        });
+
+        this.lastEventNotified = eventType;
+
+        return {
+            subscribe: function(callbackFn) {
+
+                if (this.subscribers.size !== 0) {
+                    const subscribersToNotify = Array.from(this.subscribers.keys());
+
+                    const checkNotifyComplete = (subscriberId: string) => {
+
+                        const index = subscribersToNotify.indexOf(subscriberId);
+                        subscribersToNotify.splice(index, 1);
+
+                        if (subscribersToNotify.length === 0) {
+                            callbackFn();
+                        }
+                    };
+
+                    this.subscribers.forEach((subscriber: ISubscriber, subscriberId: string) => {
+                        if (this.eventsToWait.has(subscriberId) &&
+                            this.eventsToWait.get(subscriberId).indexOf(eventType) !== -1) {
+
+                            const actionCompletedFunction = (actionCompletedEventData, subId = subscriberId) => {
+                                if (actionCompletedEventData.type === 'ACTION_COMPLETED') {
+                                    checkNotifyComplete(subId);
+                                }
+                                this.off(actionCompletedFunction);
+
+                            };
+                            this.on(actionCompletedFunction);
+                        } else {
+                            checkNotifyComplete(subscriberId);
+                        }
+                    });
+                } else {
+                    callbackFn();
+                }
+            }.bind(this)
+        };
+    }
+
+    public isWaitingForEvent(eventName: string): boolean {
+        return Array.from(this.eventsToWait.values()).some((eventsList: string[]) =>
+            eventsList.indexOf(eventName) !== -1
+        );
+    }
+
+    protected onMessage(event: any) {
+        if (this.subscribers.has(event.data.originId)) {
+            this.eventsCallbacks.forEach((callback: Function) => {
+                callback(event.data, event);
+            });
+        }
+    }
+}
+
+export interface IPubSubEvent {
+    type: string;
+    originId: string;
+    data: any;
+}
+
+export interface ISubscriber {
+    window: Window;
+    locationUrl: string;
+}