From d88ea4a75d4ccf1dcc3485b592379adddab527cf Mon Sep 17 00:00:00 2001
From: Sam Freund <techguy763@gmail.com>
Date: Fri, 4 Jul 2025 16:43:17 -0500
Subject: [PATCH] De-conflict camera names and hostnames by use of a banner
 (#1982)

---
 .../stores/settings/GeneralSettingsStore.ts   |   8 +-
 photon-client/src/types/SettingTypes.ts       |   2 +
 photon-client/src/views/DashboardView.vue     |  34 ++++-
 .../common/configuration/NetworkConfig.java   |   2 +
 .../networktables/NetworkTablesManager.java   | 126 +++++++++++++++++-
 .../dataflow/websocket/UIGeneralSettings.java |   8 +-
 .../websocket/UIPhotonConfiguration.java      |   5 +-
 .../common/networking/NetworkManager.java     |  29 ++++
 8 files changed, 202 insertions(+), 12 deletions(-)

diff --git a/photon-client/src/stores/settings/GeneralSettingsStore.ts b/photon-client/src/stores/settings/GeneralSettingsStore.ts
index f9614bcd3..e5f345823 100644
--- a/photon-client/src/stores/settings/GeneralSettingsStore.ts
+++ b/photon-client/src/stores/settings/GeneralSettingsStore.ts
@@ -28,7 +28,9 @@ export const useSettingsStore = defineStore("settings", {
       hardwarePlatform: undefined,
       mrCalWorking: true,
       availableModels: [],
-      supportedBackends: []
+      supportedBackends: [],
+      conflictingHostname: false,
+      conflictingCameras: ""
     },
     network: {
       ntServerAddress: "",
@@ -107,7 +109,9 @@ export const useSettingsStore = defineStore("settings", {
         gpuAcceleration: data.general.gpuAcceleration || undefined,
         mrCalWorking: data.general.mrCalWorking,
         availableModels: data.general.availableModels || undefined,
-        supportedBackends: data.general.supportedBackends || []
+        supportedBackends: data.general.supportedBackends || [],
+        conflictingHostname: data.general.conflictingHostname || false,
+        conflictingCameras: data.general.conflictingCameras || ""
       };
       this.lighting = data.lighting;
       this.network = data.networkSettings;
diff --git a/photon-client/src/types/SettingTypes.ts b/photon-client/src/types/SettingTypes.ts
index 0933d6b6e..cec92713f 100644
--- a/photon-client/src/types/SettingTypes.ts
+++ b/photon-client/src/types/SettingTypes.ts
@@ -10,6 +10,8 @@ export interface GeneralSettings {
   mrCalWorking: boolean;
   availableModels: ObjectDetectionModelProperties[];
   supportedBackends: string[];
+  conflictingHostname: boolean;
+  conflictingCameras: string;
 }
 
 export interface ObjectDetectionModelProperties {
diff --git a/photon-client/src/views/DashboardView.vue b/photon-client/src/views/DashboardView.vue
index 553739451..c42efbdf6 100644
--- a/photon-client/src/views/DashboardView.vue
+++ b/photon-client/src/views/DashboardView.vue
@@ -6,6 +6,7 @@ import StreamConfigCard from "@/components/dashboard/StreamConfigCard.vue";
 import PipelineConfigCard from "@/components/dashboard/ConfigOptions.vue";
 import { useCameraSettingsStore } from "@/stores/settings/CameraSettingsStore";
 import { useStateStore } from "@/stores/StateStore";
+import { useSettingsStore } from "@/stores/settings/GeneralSettingsStore";
 
 const cameraViewType = computed<number[]>({
   get: (): number[] => {
@@ -50,22 +51,49 @@ const arducamWarningShown = computed<boolean>(() => {
   );
 });
 
+const conflictingHostnameShown = computed<boolean>(() => {
+  return useSettingsStore().general.conflictingHostname;
+});
+
+const conflictingCameraShown = computed<boolean>(() => {
+  return useSettingsStore().general.conflictingCameras.length > 0;
+});
+
 const showCameraSetupDialog = ref(useCameraSettingsStore().needsCameraConfiguration);
 </script>
 
 <template>
   <v-container class="pa-3" fluid>
+    <v-banner v-if="arducamWarningShown" rounded color="error" dark class="mb-3" icon="mdi-alert-circle-outline">
+      <span
+        >Arducam Camera Detected! Please configure the camera model in the <a href="#/cameras">Cameras tab</a>!
+      </span>
+    </v-banner>
     <v-banner
-      v-if="arducamWarningShown"
-      v-model="arducamWarningShown"
+      v-if="conflictingHostnameShown"
       rounded
+      bg-color="error"
       color="error"
       dark
       class="mb-3"
       icon="mdi-alert-circle-outline"
     >
       <span
-        >Arducam Camera Detected! Please configure the camera model in the <a href="#/cameras">Cameras tab</a>!
+        >Conflicting Hostname Detected! Please change the hostname in the <a href="#/settings">Settings tab</a>!
+      </span>
+    </v-banner>
+    <v-banner
+      v-if="conflictingCameraShown"
+      rounded
+      bg-color="error"
+      color="error"
+      dark
+      class="mb-3"
+      icon="mdi-alert-circle-outline"
+    >
+      <span
+        >Conflicting Camera Name(s) Detected! Please change the name(s) of
+        {{ useSettingsStore().general.conflictingCameras }}!
       </span>
     </v-banner>
     <v-row no-gutters>
diff --git a/photon-core/src/main/java/org/photonvision/common/configuration/NetworkConfig.java b/photon-core/src/main/java/org/photonvision/common/configuration/NetworkConfig.java
index f0023dd13..bb0c6cd05 100644
--- a/photon-core/src/main/java/org/photonvision/common/configuration/NetworkConfig.java
+++ b/photon-core/src/main/java/org/photonvision/common/configuration/NetworkConfig.java
@@ -128,6 +128,8 @@ public class NetworkConfig {
                 + setDHCPcommand
                 + ", shouldManage="
                 + shouldManage
+                + ", shouldPublishProto="
+                + shouldPublishProto
                 + "]";
     }
 }
diff --git a/photon-core/src/main/java/org/photonvision/common/dataflow/networktables/NetworkTablesManager.java b/photon-core/src/main/java/org/photonvision/common/dataflow/networktables/NetworkTablesManager.java
index 2ab20defb..5b112ddf1 100644
--- a/photon-core/src/main/java/org/photonvision/common/dataflow/networktables/NetworkTablesManager.java
+++ b/photon-core/src/main/java/org/photonvision/common/dataflow/networktables/NetworkTablesManager.java
@@ -19,15 +19,21 @@ package org.photonvision.common.dataflow.networktables;
 
 import edu.wpi.first.apriltag.AprilTagFieldLayout;
 import edu.wpi.first.networktables.LogMessage;
+import edu.wpi.first.networktables.MultiSubscriber;
 import edu.wpi.first.networktables.NetworkTable;
 import edu.wpi.first.networktables.NetworkTableEvent;
 import edu.wpi.first.networktables.NetworkTableEvent.Kind;
 import edu.wpi.first.networktables.NetworkTableInstance;
 import edu.wpi.first.networktables.StringSubscriber;
+import edu.wpi.first.wpilibj.Alert;
+import edu.wpi.first.wpilibj.Alert.AlertType;
+import edu.wpi.first.wpilibj.smartdashboard.SmartDashboard;
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.EnumSet;
 import java.util.HashMap;
 import org.photonvision.PhotonVersion;
+import org.photonvision.common.configuration.CameraConfiguration;
 import org.photonvision.common.configuration.ConfigManager;
 import org.photonvision.common.configuration.NetworkConfig;
 import org.photonvision.common.dataflow.DataChangeService;
@@ -37,6 +43,7 @@ import org.photonvision.common.hardware.HardwareManager;
 import org.photonvision.common.logging.LogGroup;
 import org.photonvision.common.logging.LogLevel;
 import org.photonvision.common.logging.Logger;
+import org.photonvision.common.networking.NetworkManager;
 import org.photonvision.common.scripting.ScriptEventType;
 import org.photonvision.common.scripting.ScriptManager;
 import org.photonvision.common.util.TimedTaskManager;
@@ -48,9 +55,19 @@ public class NetworkTablesManager {
 
     private final NetworkTableInstance ntInstance = NetworkTableInstance.getDefault();
     private final String kRootTableName = "/photonvision";
+    private final String kCoprocTableName = "coprocessors";
     private final String kFieldLayoutName = "apriltag_field_layout";
     public final NetworkTable kRootTable = ntInstance.getTable(kRootTableName);
 
+    private final MultiSubscriber sub =
+            new MultiSubscriber(ntInstance, new String[] {kRootTableName + "/" + kCoprocTableName + "/"});
+
+    // Creating the alert up here since it should be persistent
+    private final Alert conflictAlert = new Alert("PhotonAlerts", "", AlertType.kWarning);
+
+    public boolean conflictingHostname = false;
+    public String conflictingCameras = "";
+
     private boolean m_isRetryingConnection = false;
 
     private StringSubscriber m_fieldLayoutSubscriber =
@@ -70,14 +87,19 @@ public class NetworkTablesManager {
 
         ntDriverStation = new NTDriverStation(this.getNTInst());
 
-        // Get the UI state in sync with the backend. NT should fire a callback when it first connects
-        // to the robot
+        // This should start as false, since we don't know if there's a conflict yet
+        conflictAlert.set(false);
+
+        // Get the UI state in sync with the backend. NT should fire a callback when it
+        // first connects to the robot
         broadcastConnectedStatus();
     }
 
     public void registerTimedTasks() {
         m_timeSync.start();
         TimedTaskManager.getInstance().addTask("NTManager", this::ntTick, 5000);
+        TimedTaskManager.getInstance()
+                .addTask("CheckHostnameAndCameraNames", this::checkHostnameAndCameraNames, 10000);
     }
 
     private static NetworkTablesManager INSTANCE;
@@ -205,6 +227,101 @@ public class NetworkTablesManager {
         kRootTable.getEntry("buildDate").setString(PhotonVersion.buildDate);
     }
 
+    /**
+     * Publishes the hostname and camera names to a table using the MAC address as a key. Then checks
+     * for conflicts of hostname or camera names across other coprocessors that are also publishing to
+     * this table.
+     */
+    private void checkHostnameAndCameraNames() {
+        String MAC = NetworkManager.getInstance().getMACAddress();
+        if (MAC == null || MAC.isEmpty()) {
+            logger.error("Cannot check hostname and camera names, MAC address is not set!");
+            return;
+        }
+
+        String hostname = ConfigManager.getInstance().getConfig().getNetworkConfig().hostname;
+        if (hostname == null || hostname.isEmpty()) {
+            logger.error("Cannot check hostname and camera names, hostname is not set!");
+            return;
+        }
+
+        HashMap<String, CameraConfiguration> cameraConfigs =
+                ConfigManager.getInstance().getConfig().getCameraConfigurations();
+        String[] cameraNames =
+                cameraConfigs.entrySet().stream()
+                        .map(entry -> entry.getValue().nickname)
+                        .toArray(String[]::new);
+
+        // Create a subtable under the photonvision root table
+        NetworkTable coprocTable = kRootTable.getSubTable(kCoprocTableName);
+
+        // Create a subtable for this coprocessor using its MAC address
+        NetworkTable macTable = coprocTable.getSubTable(MAC);
+
+        // Publish the hostname and camera names
+        macTable.getEntry("hostname").setString(hostname);
+        macTable.getEntry("cameraNames").setStringArray(cameraNames);
+        logger.debug("Published hostname and camera names to NT under MAC: " + MAC);
+
+        boolean conflictingHostname = false;
+        StringBuilder conflictingCameras = new StringBuilder();
+
+        // Check for conflicts with other coprocessors
+        for (String key : coprocTable.getSubTables()) {
+            // Check that key is formatted like a MAC address
+            if (!key.matches("([0-9A-F]{2}-){5}[0-9A-F]{2}")) {
+                logger.warn("Skipping non-MAC key in conflict detection: " + key);
+                continue;
+            }
+
+            if (!key.equals(MAC)) { // Skip our own entry
+                NetworkTable otherCoprocTable = coprocTable.getSubTable(key);
+                String otherHostname = otherCoprocTable.getEntry("hostname").getString("");
+                String[] otherCameraNames =
+                        otherCoprocTable.getEntry("cameraNames").getStringArray(new String[0]);
+                // Check for hostname conflicts
+                if (otherHostname.equals(hostname)) {
+                    logger.warn("Hostname conflict detected with coprocessor " + key + ": " + hostname);
+                    conflictingHostname = true;
+                }
+
+                // Check for camera name conflicts
+                for (String cameraName : cameraNames) {
+                    if (Arrays.stream(otherCameraNames).anyMatch(otherName -> otherName.equals(cameraName))) {
+                        logger.warn("Camera name conflict detected: " + cameraName);
+                        conflictingCameras.append(
+                                conflictingCameras.isEmpty() ? cameraName : ", " + cameraName);
+                    }
+                }
+            }
+        }
+
+        boolean hasChanged =
+                this.conflictingHostname != conflictingHostname
+                        || !this.conflictingCameras.equals(conflictingCameras.toString());
+
+        // Publish the conflict status
+        if (hasChanged) {
+            DataChangeService.getInstance()
+                    .publishEvent(
+                            new OutgoingUIEvent<>(
+                                    "fullsettings",
+                                    UIPhotonConfiguration.programStateToUi(ConfigManager.getInstance().getConfig())));
+        }
+
+        conflictAlert.setText(
+                conflictingHostname
+                        ? "Hostname conflict detected for " + hostname + "!"
+                        : ""
+                                + (conflictingCameras.isEmpty()
+                                        ? ""
+                                        : " Camera name conflict detected: " + conflictingCameras.toString() + "!"));
+        conflictAlert.set(conflictingHostname || !conflictingCameras.isEmpty());
+        SmartDashboard.updateValues();
+        this.conflictingHostname = conflictingHostname;
+        this.conflictingCameras = conflictingCameras.toString();
+    }
+
     public void setConfig(NetworkConfig config) {
         if (config.runNTServer) {
             setServerMode();
@@ -246,9 +363,8 @@ public class NetworkTablesManager {
 
     // So it seems like if Photon starts before the robot NT server does, and both aren't static IP,
     // it'll never connect. This hack works around it by restarting the client/server while the nt
-    // instance
-    // isn't connected, same as clicking the save button in the settings menu (or restarting the
-    // service)
+    // instance isn't connected, same as clicking the save button in the settings menu (or restarting
+    // the service)
     private void ntTick() {
         if (!ntInstance.isConnected()
                 && !ConfigManager.getInstance().getConfig().getNetworkConfig().runNTServer) {
diff --git a/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIGeneralSettings.java b/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIGeneralSettings.java
index cb981e369..d824d1557 100644
--- a/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIGeneralSettings.java
+++ b/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIGeneralSettings.java
@@ -28,7 +28,9 @@ public class UIGeneralSettings {
             NeuralNetworkPropertyManager.ModelProperties[] availableModels,
             List<String> supportedBackends,
             String hardwareModel,
-            String hardwarePlatform) {
+            String hardwarePlatform,
+            boolean conflictingHostname,
+            String conflictingCameras) {
         this.version = version;
         this.gpuAcceleration = gpuAcceleration;
         this.mrCalWorking = mrCalWorking;
@@ -36,6 +38,8 @@ public class UIGeneralSettings {
         this.supportedBackends = supportedBackends;
         this.hardwareModel = hardwareModel;
         this.hardwarePlatform = hardwarePlatform;
+        this.conflictingHostname = conflictingHostname;
+        this.conflictingCameras = conflictingCameras;
     }
 
     public String version;
@@ -45,4 +49,6 @@ public class UIGeneralSettings {
     public List<String> supportedBackends;
     public String hardwareModel;
     public String hardwarePlatform;
+    public boolean conflictingHostname;
+    public String conflictingCameras;
 }
diff --git a/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIPhotonConfiguration.java b/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIPhotonConfiguration.java
index 971d853a3..003f3f135 100644
--- a/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIPhotonConfiguration.java
+++ b/photon-core/src/main/java/org/photonvision/common/dataflow/websocket/UIPhotonConfiguration.java
@@ -21,6 +21,7 @@ import java.util.List;
 import org.photonvision.PhotonVersion;
 import org.photonvision.common.configuration.NeuralNetworkModelManager;
 import org.photonvision.common.configuration.PhotonConfiguration;
+import org.photonvision.common.dataflow.networktables.NetworkTablesManager;
 import org.photonvision.common.hardware.Platform;
 import org.photonvision.common.networking.NetworkManager;
 import org.photonvision.common.networking.NetworkUtils;
@@ -59,7 +60,9 @@ public class UIPhotonConfiguration {
                                 c.getHardwareConfig().deviceName().isEmpty()
                                         ? Platform.getHardwareModel()
                                         : c.getHardwareConfig().deviceName(),
-                                Platform.getPlatformName()),
+                                Platform.getPlatformName(),
+                                NetworkTablesManager.getInstance().conflictingHostname,
+                                NetworkTablesManager.getInstance().conflictingCameras),
                         c.getApriltagFieldLayout()),
                 VisionSourceManager.getInstance().getVisionModules().stream()
                         .map(VisionModule::toUICameraConfig)
diff --git a/photon-core/src/main/java/org/photonvision/common/networking/NetworkManager.java b/photon-core/src/main/java/org/photonvision/common/networking/NetworkManager.java
index 0abf4c3e3..0d78fe4cb 100644
--- a/photon-core/src/main/java/org/photonvision/common/networking/NetworkManager.java
+++ b/photon-core/src/main/java/org/photonvision/common/networking/NetworkManager.java
@@ -179,6 +179,35 @@ public class NetworkManager {
         }
     }
 
+    public String getMACAddress() {
+        var config = ConfigManager.getInstance().getConfig().getNetworkConfig();
+        if (config.networkManagerIface == null || config.networkManagerIface.isBlank()) {
+            logger.error("No network interface configured, cannot get MAC address!");
+            return "";
+        }
+        try {
+            NetworkInterface iFace = NetworkInterface.getByName(config.networkManagerIface);
+            if (iFace == null) {
+                logger.error("Network interface " + config.networkManagerIface + " not found!");
+                return "";
+            }
+            byte[] mac = iFace.getHardwareAddress();
+            if (mac == null) {
+                logger.error("No MAC address found for " + config.networkManagerIface);
+                return "";
+            }
+            StringBuilder sb = new StringBuilder(17);
+            for (byte b : mac) {
+                sb.append(String.format("%02X-", b));
+            }
+            sb.setLength(sb.length() - 1);
+            return sb.toString();
+        } catch (Exception e) {
+            logger.error("Error getting MAC address for " + config.networkManagerIface, e);
+            return "";
+        }
+    }
+
     private void setConnectionDHCP(NetworkConfig config) {
         String connName = "dhcp-" + config.networkManagerIface;