From 19e799f11d2d104b74f05e5d83b76f58d262afc6 Mon Sep 17 00:00:00 2001
From: Andrew Welker <awelker@pepperdash.com>
Date: Thu, 26 Jun 2025 17:12:36 -0400
Subject: [PATCH] fix: debounce device info events

In some cases, multiple device info update events are triggering,
causing the queue to be flooded with multiple unneccessary messages containing the same info.
This clogs the queue and makes it harder for UIs to come online when Essentials restarts,
especially in systems with a lot of NVX devices.

The events are now debounced. If there are no new messages for 1 second, then the MC message
is sent out.
---
 .../Messengers/DeviceInfoMessenger.cs         | 58 +++++++++++++++++--
 1 file changed, 53 insertions(+), 5 deletions(-)

diff --git a/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/DeviceInfoMessenger.cs b/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/DeviceInfoMessenger.cs
index ffd58948..c588195e 100644
--- a/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/DeviceInfoMessenger.cs
+++ b/src/PepperDash.Essentials.MobileControl.Messengers/Messengers/DeviceInfoMessenger.cs
@@ -2,27 +2,69 @@
 using Newtonsoft.Json.Linq;
 using PepperDash.Core;
 using PepperDash.Essentials.Core.DeviceInfo;
+using System.Timers;
 
 namespace PepperDash.Essentials.AppServer.Messengers
 {
+    /// <summary>
+    /// Facilitates communication of device information by providing mechanisms for status updates and  device
+    /// information reporting.
+    /// </summary>
+    /// <remarks>The <see cref="DeviceInfoMessenger"/> class integrates with an <see
+    /// cref="IDeviceInfoProvider"/> to  manage device-specific information. It uses a debounce timer to limit the
+    /// frequency of updates,  ensuring efficient communication. The timer is initialized with a 1-second interval and
+    /// is disabled  by default. This class also subscribes to device information change events and provides actions for
+    /// reporting full device status and triggering updates.</remarks>
     public class DeviceInfoMessenger : MessengerBase
     {
         private readonly IDeviceInfoProvider _deviceInfoProvider;
+
+        private readonly Timer debounceTimer;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="DeviceInfoMessenger"/> class, which facilitates communication
+        /// of device information.
+        /// </summary>
+        /// <remarks>The messenger uses a debounce timer to limit the frequency of certain operations. The
+        /// timer is initialized with a 1-second interval and is disabled by default.</remarks>
+        /// <param name="key">A unique identifier for the messenger instance.</param>
+        /// <param name="messagePath">The path used for sending and receiving messages.</param>
+        /// <param name="device">An implementation of <see cref="IDeviceInfoProvider"/> that provides device-specific information.</param>
         public DeviceInfoMessenger(string key, string messagePath, IDeviceInfoProvider device) : base(key, messagePath, device as Device)
         {
             _deviceInfoProvider = device;
-        }
 
+            debounceTimer = new Timer(1000)
+            {
+                Enabled = false,
+                AutoReset = false
+            };
+
+            debounceTimer.Elapsed += DebounceTimer_Elapsed;
+        }
+
+        private void DebounceTimer_Elapsed(object sender, ElapsedEventArgs e)
+        {
+            PostStatusMessage(JToken.FromObject(new
+            {
+                deviceInfo = _deviceInfoProvider.DeviceInfo
+            }));
+        }
+
+        /// <summary>
+        /// Registers actions and event handlers for device information updates and status reporting.
+        /// </summary>
+        /// <remarks>This method sets up actions for handling device status updates and reporting full
+        /// device status. It also subscribes to the <see cref="IDeviceInfoProvider.DeviceInfoChanged"/> event to
+        /// trigger debounced updates when the device information changes.</remarks>
         protected override void RegisterActions()
         {
             base.RegisterActions();
 
             _deviceInfoProvider.DeviceInfoChanged += (o, a) =>
             {
-                PostStatusMessage(JToken.FromObject(new
-                {
-                    deviceInfo = a.DeviceInfo
-                }));
+                debounceTimer.Stop();
+                debounceTimer.Start();
             };
 
             AddAction("/fullStatus", (id, context) => PostStatusMessage(new DeviceInfoStateMessage
@@ -34,6 +76,12 @@ namespace PepperDash.Essentials.AppServer.Messengers
         }
     }
 
+    /// <summary>
+    /// Represents a message containing the state information of a device, including detailed device information.
+    /// </summary>
+    /// <remarks>This class is used to encapsulate the state of a device along with its associated
+    /// information. It extends <see cref="DeviceStateMessageBase"/> to provide additional details about the
+    /// device.</remarks>
     public class DeviceInfoStateMessage : DeviceStateMessageBase
     {
         [JsonProperty("deviceInfo")]