Fix emitter leaks, style, tree swaps

events/EventBus.ts

@@ -6,6 +6,12 @@ export interface EventBusInterface {
   subscribe<MessageType>(event: Event<MessageType>, callback:(msg: MessageType) => void): void
   unsubscribeAll<MessageType>(event: Event<MessageType>): void
   emit<MessageType>(event: Event<MessageType>, msg: MessageType): void
+  unsubscribe<MessageType>(event: Event<MessageType>, callback: any): void
+}
+
+interface CallbackStore {
+  wrappedCallback: any
+  callback: any
 }
 
 class IpcMainEventBus implements EventBusInterface {
@@ -27,6 +33,10 @@ class IpcMainEventBus implements EventBusInterface {
     this.ipc.removeAllListeners(event.topic)
   }
 
+  public unsubscribe<MessageType>(event: Event<MessageType>, callback: any) {
+    throw new Error('Not implemented') // Todo: implement
+  }
+
   public emit<MessageType>(event: Event<MessageType>, msg: MessageType) {
     if (!this.client.isDestroyed()) {
       this.client.send(event.topic, msg)
@@ -36,18 +46,40 @@ class IpcMainEventBus implements EventBusInterface {
 
 class IpcRendererEventBus implements EventBusInterface {
   private ipc: IpcRenderer
+  private callbacks: CallbackStore[] = []
+
   constructor(ipc: IpcRenderer) {
     this.ipc = ipc
   }
 
   public subscribe<MessageType>(event: Event<MessageType>, callback:(msg: MessageType) => void) {
-    this.ipc.on(event.topic, (_event: any, arg: any) => callback(arg))
+    const wrappedCallback = (_event: any, arg: any) => {
+      callback(arg)
+    }
+
+    this.ipc.on(event.topic, wrappedCallback)
+
+    this.callbacks.push({
+      callback,
+      wrappedCallback,
+    })
   }
 
   public unsubscribeAll<MessageType>(event: Event<MessageType>) {
     this.ipc.removeAllListeners(event.topic)
   }
 
+  public unsubscribe<MessageType>(event: Event<MessageType>, callback: any) {
+    debugger
+    const item = this.callbacks.find(store => store.callback === callback)
+    if (!item) {
+      return
+    }
+
+    this.ipc.removeListener(event.topic, item.wrappedCallback)
+    this.callbacks = this.callbacks.filter(a => a !== item)
+  }
+
   public emit<MessageType>(event: Event<MessageType>, msg: MessageType) {
     this.ipc.send(event.topic, msg)
   }