From f8738a9053a060ee3f4c3f44398b468041682f06 Mon Sep 17 00:00:00 2001
From: Jonathan Arndt <jarndt@pepperdash.com>
Date: Wed, 19 Aug 2026 12:38:53 -0700
Subject: [PATCH] feat(messenger): implement client-specific event messaging
 for tech password validation

---
 .../Messengers/ITechPasswordMessenger.cs      | 24 +++++++++++++++++--
 .../Messengers/MessengerBase.cs               | 23 ++++++++++++++++++
 2 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/ITechPasswordMessenger.cs b/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/ITechPasswordMessenger.cs
index 283ef0c8..45453bc1 100644
--- a/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/ITechPasswordMessenger.cs
+++ b/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/ITechPasswordMessenger.cs
@@ -11,6 +11,15 @@ namespace PepperDash.Essentials.AppServer.Messengers
     {
         private readonly ITechPassword _room;
 
+        // Captures the id of the client whose /validateTechPassword request is in flight, so the
+        // TechPasswordValidateResult handler below can reply to only that client instead of
+        // broadcasting to every connected panel. Relies on ValidateTechPassword firing the event
+        // synchronously (true for all known ITechPassword implementations); if a future
+        // implementation validates asynchronously, _pendingClientId will already be null when the
+        // handler runs and this degrades to the previous broadcast behavior.
+        private readonly object _pendingLock = new object();
+        private string _pendingClientId;
+
         public ITechPasswordMessenger(string key, string messagePath, ITechPassword room)
             : base(key, messagePath, room as IKeyName)
         {
@@ -28,7 +37,12 @@ namespace PepperDash.Essentials.AppServer.Messengers
             {
                 var password = content.Value<string>("password");
 
-                _room.ValidateTechPassword(password);
+                lock (_pendingLock)
+                {
+                    _pendingClientId = id;
+                    _room.ValidateTechPassword(password);
+                    _pendingClientId = null;
+                }
             });
 
             AddAction("/setTechPassword", (id, content) =>
@@ -45,12 +59,18 @@ namespace PepperDash.Essentials.AppServer.Messengers
 
             _room.TechPasswordValidateResult += (sender, args) =>
             {
+                string clientId;
+                lock (_pendingLock)
+                {
+                    clientId = _pendingClientId;
+                }
+
                 var evt = new ITechPasswordEventMessage
                 {
                     IsValid = args.IsValid
                 };
 
-                PostEventMessage(evt, "passwordValidationResult");
+                PostEventMessage(evt, "passwordValidationResult", clientId);
             };
         }
 
diff --git a/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/MessengerBase.cs b/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/MessengerBase.cs
index eb3afec3..cd59db6e 100644
--- a/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/MessengerBase.cs
+++ b/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/MessengerBase.cs
@@ -405,5 +405,28 @@ namespace PepperDash.Essentials.AppServer.Messengers
             });
         }
 
+        /// <summary>
+        /// Helper for posting an event message to a single client. A null/empty clientId falls back
+        /// to the existing broadcast behavior of the other PostEventMessage overloads.
+        /// </summary>
+        /// <param name="message"></param>
+        /// <param name="eventType"></param>
+        /// <param name="clientId">Client id that will direct the message back to only that client</param>
+        protected void PostEventMessage(DeviceEventMessageBase message, string eventType, string clientId)
+        {
+            message.Key = _device.Key;
+
+            message.Name = _device.Name;
+
+            message.EventType = eventType;
+
+            AppServerController?.SendMessageObject(new MobileControlMessage
+            {
+                Type = $"/event{MessagePath}/{eventType}",
+                ClientId = clientId,
+                Content = JToken.FromObject(message),
+            });
+        }
+
     }
 }