From 3bd5d424e72f707edd3e3863ea679c97ba4ea822 Mon Sep 17 00:00:00 2001
From: ababak <artemio.babak@gmail.com>
Date: Tue, 7 Apr 2026 17:45:48 +0300
Subject: [PATCH] fix: add subscriberCmdIds reverse index and defensive guard
 in processPendingUpdates

---
 .../core/ws/telemetry-websocket.service.ts    | 21 ++++++++++++++-----
 ui-ngx/src/app/core/ws/websocket.service.ts   | 11 +++++++---
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
index 2d7c8af529..fbe69d55ae 100644
--- a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
+++ b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
@@ -81,6 +81,12 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
         const cmdId = this.nextCmdId();
         if (!(subscriptionCommand instanceof MarkAsReadCmd) && !(subscriptionCommand instanceof MarkAllAsReadCmd)) {
           this.subscribersMap.set(cmdId, subscriber);
+          let cmdIds = this.subscriberCmdIds.get(subscriber);
+          if (!cmdIds) {
+            cmdIds = new Set<number>();
+            this.subscriberCmdIds.set(subscriber, cmdIds);
+          }
+          cmdIds.add(cmdId);
         }
         subscriptionCommand.cmdId = cmdId;
         this.cmdWrapper.cmds.push(subscriptionCommand);
@@ -141,6 +147,13 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
           const cmdId = subscriptionCommand.cmdId;
           if (cmdId) {
             this.subscribersMap.delete(cmdId);
+            const cmdIds = this.subscriberCmdIds.get(subscriber);
+            if (cmdIds) {
+              cmdIds.delete(cmdId);
+              if (cmdIds.size === 0) {
+                this.subscriberCmdIds.delete(subscriber);
+              }
+            }
           }
         }
       );
@@ -183,11 +196,9 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
 
   private syncCommandId(subscriptionCommand: WebsocketCmd, subscriber: TelemetrySubscriber) {
     if (!this.subscribersMap.has(subscriptionCommand.cmdId)) {
-      for (const [cmdId, sub] of this.subscribersMap.entries()) {
-        if (sub === subscriber) {
-          subscriptionCommand.cmdId = cmdId;
-          break;
-        }
+      const cmdIds = this.subscriberCmdIds.get(subscriber);
+      if (cmdIds?.size) {
+        subscriptionCommand.cmdId = cmdIds.values().next().value;
       }
     }
   }
diff --git a/ui-ngx/src/app/core/ws/websocket.service.ts b/ui-ngx/src/app/core/ws/websocket.service.ts
index b94caa04c8..7b8c488082 100644
--- a/ui-ngx/src/app/core/ws/websocket.service.ts
+++ b/ui-ngx/src/app/core/ws/websocket.service.ts
@@ -50,6 +50,7 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
   lastCmdId = 0;
   subscribersCount = 0;
   subscribersMap = new Map<number, TelemetrySubscriber | NotificationSubscriber>();
+  subscriberCmdIds = new Map<WsSubscriber, Set<number>>();
 
   reconnectSubscribers = new Set<WsSubscriber>();
   pendingUpdates = new Set<T>();
@@ -136,6 +137,7 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
     }
     this.lastCmdId = 0;
     this.subscribersMap.clear();
+    this.subscriberCmdIds.clear();
     this.subscribersCount = 0;
     this.cmdWrapper.clear();
     if (close) {
@@ -304,10 +306,13 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
 
   private processPendingUpdates() {
     if (this.pendingUpdates.size > 0) {
-      this.pendingUpdates.forEach((subscriber) => {
-        this.update(subscriber);
-      });
+      const subscribers = Array.from(this.pendingUpdates);
       this.pendingUpdates.clear();
+      for (const subscriber of subscribers) {
+        if (this.subscriberCmdIds.has(subscriber)) {
+          this.update(subscriber);
+        }
+      }
     }
   }
 }