fix: separate draft event subscriptions and make it a public api (#1565)

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- [ ] Code changes are tested

## Description of the changes, What, Why and How?

## Changelog

-

Author: isekovanic

src/messageComposer/messageComposer.ts

@@ -364,6 +364,16 @@ export class MessageComposer extends WithSubscriptions {
     });
   }
 
+  public registerDraftEventSubscriptions = () => {
+    const unsubscribeDraftUpdated = this.subscribeDraftUpdated();
+    const unsubscribeDraftDeleted = this.subscribeDraftDeleted();
+
+    return () => {
+      unsubscribeDraftUpdated();
+      unsubscribeDraftDeleted();
+    };
+  };
+
   public registerSubscriptions = (): UnregisterSubscriptions => {
     if (!this.hasSubscriptions) {
       this.addUnsubscribeFunction(this.subscribeMessageComposerSetupStateChange());
@@ -552,7 +562,7 @@ export class MessageComposer extends WithSubscriptions {
     });
 
   private subscribeMessageComposerConfigStateChanged = () => {
-    let draftUnsubscribeFunctions: Unsubscribe[] | null;
+    let draftUnsubscribeFunction: Unsubscribe | null;
 
     const unsubscribe = this.configState.subscribeWithSelector(
       (currentValue) => ({
@@ -567,20 +577,17 @@ export class MessageComposer extends WithSubscriptions {
           });
         }
 
-        if (draftsEnabled && !draftUnsubscribeFunctions) {
-          draftUnsubscribeFunctions = [
-            this.subscribeDraftUpdated(),
-            this.subscribeDraftDeleted(),
-          ];
-        } else if (!draftsEnabled && draftUnsubscribeFunctions) {
-          draftUnsubscribeFunctions.forEach((fn) => fn());
-          draftUnsubscribeFunctions = null;
+        if (draftsEnabled && !draftUnsubscribeFunction) {
+          draftUnsubscribeFunction = this.registerDraftEventSubscriptions();
+        } else if (!draftsEnabled && draftUnsubscribeFunction) {
+          draftUnsubscribeFunction();
+          draftUnsubscribeFunction = null;
         }
       },
     );
 
     return () => {
-      draftUnsubscribeFunctions?.forEach((unsubscribe) => unsubscribe());
+      draftUnsubscribeFunction?.();
       unsubscribe();
     };
   };

test/unit/MessageComposer/messageComposer.test.ts

@@ -528,6 +528,48 @@ describe('MessageComposer', () => {
       expect(messageComposer.hasSubscriptions).toBe(false);
     });
 
+    it('should register draft subscriptions only once if done through registerSubscriptions', () => {
+      const { messageComposer } = setup({
+        config: { drafts: { enabled: true } },
+      });
+
+      const draftEventSubscriptionsSpy = vi.spyOn(
+        messageComposer,
+        'registerDraftEventSubscriptions',
+      );
+
+      messageComposer.registerSubscriptions();
+      messageComposer.registerSubscriptions();
+
+      expect(draftEventSubscriptionsSpy).toHaveBeenCalledOnce();
+    });
+
+    it('should allow multiple registrations of draft ws events if done through registerDraftEventSubscriptions', () => {
+      const { messageComposer } = setup({
+        config: { drafts: { enabled: true } },
+      });
+
+      const subscribeDraftUpdatedSpy = vi
+        // @ts-expect-error - we are testing private properties
+        .spyOn(messageComposer, 'subscribeDraftUpdated');
+      const subscribeDraftDeletedSpy = vi
+        // @ts-expect-error - we are testing private properties
+        .spyOn(messageComposer, 'subscribeDraftDeleted');
+
+      messageComposer.registerSubscriptions();
+
+      expect(subscribeDraftUpdatedSpy).toHaveBeenCalledOnce();
+      expect(subscribeDraftDeletedSpy).toHaveBeenCalledOnce();
+
+      subscribeDraftUpdatedSpy.mockClear();
+      subscribeDraftDeletedSpy.mockClear();
+
+      messageComposer.registerDraftEventSubscriptions();
+
+      expect(subscribeDraftUpdatedSpy).toHaveBeenCalledOnce();
+      expect(subscribeDraftDeletedSpy).toHaveBeenCalledOnce();
+    });
+
     it('should set quoted message', () => {
       const { messageComposer } = setup();
       const quotedMessage = {
@@ -1302,37 +1344,26 @@ describe('MessageComposer', () => {
         config: { drafts: { enabled: false } },
       });
 
-      const unsubscribeDraftUpdated = vi.fn();
-      const unsubscribeDraftDeleted = vi.fn();
+      const unsubscribeDraftEvents = vi.fn();
 
-      // @ts-expect-error - we are testing private properties
-      const subscribeDraftUpdatedSpy = vi
-        .spyOn(messageComposer, 'subscribeDraftUpdated')
-        .mockImplementation(() => unsubscribeDraftUpdated);
-      // @ts-expect-error - we are testing private properties
-      const subscribeDraftDeletedSpy = vi
-        .spyOn(messageComposer, 'subscribeDraftDeleted')
-        .mockImplementation(() => unsubscribeDraftDeleted);
+      const registerDraftEventSubscriptionsSpy = vi
+        .spyOn(messageComposer, 'registerDraftEventSubscriptions')
+        .mockImplementation(() => unsubscribeDraftEvents);
 
       messageComposer.registerSubscriptions();
 
-      expect(subscribeDraftUpdatedSpy).not.toHaveBeenCalled();
-      expect(subscribeDraftDeletedSpy).not.toHaveBeenCalled();
+      expect(registerDraftEventSubscriptionsSpy).not.toHaveBeenCalled();
 
       messageComposer.updateConfig({ drafts: { enabled: true } });
 
-      expect(subscribeDraftUpdatedSpy).toHaveBeenCalledTimes(1);
-      expect(subscribeDraftDeletedSpy).toHaveBeenCalledTimes(1);
+      expect(registerDraftEventSubscriptionsSpy).toHaveBeenCalledTimes(1);
 
-      subscribeDraftUpdatedSpy.mockClear();
-      subscribeDraftDeletedSpy.mockClear();
+      registerDraftEventSubscriptionsSpy.mockClear();
 
       messageComposer.updateConfig({ drafts: { enabled: false } });
 
-      expect(unsubscribeDraftUpdated).toHaveBeenCalledTimes(1);
-      expect(unsubscribeDraftDeleted).toHaveBeenCalledTimes(1);
-      expect(subscribeDraftUpdatedSpy).not.toHaveBeenCalled();
-      expect(subscribeDraftDeletedSpy).not.toHaveBeenCalled();
+      expect(unsubscribeDraftEvents).toHaveBeenCalledTimes(1);
+      expect(registerDraftEventSubscriptionsSpy).not.toHaveBeenCalled();
     });
   });
 });