Load DeviceSettings.config as an overlay on HikvisionServiceConfig

After loading serviceconfig.json, apply DeviceSettings.config values onto the existing config properties without changing runtime behavior or property names.

HikvisionAttendanceWindowsService.cs

@@ -237,7 +237,7 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
             {
                 if (!File.Exists(configPath))
                 {
-                    return new HikvisionServiceConfig
+                    var missingCfg = new HikvisionServiceConfig
                     {
                         LogDirectory = @"C:\Users\Public\HikvisionAttendanceService",
                         SqlConnectionString = "",
@@ -284,6 +284,9 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
                         UserSyncFaceCacheDirectory = "",
                         SyncPolicies = new UserSyncPoliciesConfig()
                     };
+                    ApplyDeviceSettingsOverlay(missingCfg, configPath);
+                    NormalizeLoadedDeviceConfig(missingCfg);
+                    return missingCfg;
                 }
 
                 var raw = File.ReadAllText(configPath);
@@ -296,6 +299,7 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
                     {
                         var cfg = (HikvisionServiceConfig)serializer.ReadObject(ms);
                         ApplyEnvironmentOverrides(cfg);
+                        ApplyDeviceSettingsOverlay(cfg, configPath);
                         NormalizeLoadedDeviceConfig(cfg);
                         return cfg;
                     }
@@ -308,6 +312,7 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
                     {
                         var cfg = (HikvisionServiceConfig)serializer.ReadObject(ms);
                         ApplyEnvironmentOverrides(cfg);
+                        ApplyDeviceSettingsOverlay(cfg, configPath);
                         NormalizeLoadedDeviceConfig(cfg);
                         return cfg;
                     }
@@ -315,7 +320,7 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
             }
             catch
             {
-                return new HikvisionServiceConfig
+                var fallbackCfg = new HikvisionServiceConfig
                 {
                     LogDirectory = @"C:\Users\Public\HikvisionAttendanceService",
                     SqlConnectionString = "",
@@ -362,6 +367,9 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
                     UserSyncFaceCacheDirectory = "",
                     SyncPolicies = new UserSyncPoliciesConfig()
                 };
+                ApplyDeviceSettingsOverlay(fallbackCfg, configPath);
+                NormalizeLoadedDeviceConfig(fallbackCfg);
+                return fallbackCfg;
             }
         }
 
@@ -481,6 +489,60 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
                 cfg.DbPort = parsedPort;
         }
 
+        /// <summary>
+        /// Overlays device-scope / template-direction settings from DeviceSettings.config
+        /// (same folder as serviceconfig.json). Property names and behavior are unchanged.
+        /// </summary>
+        private static void ApplyDeviceSettingsOverlay(HikvisionServiceConfig cfg, string serviceConfigPath)
+        {
+            if (cfg == null)
+                return;
+
+            string dir;
+            try
+            {
+                dir = Path.GetDirectoryName(Path.GetFullPath(serviceConfigPath ?? "")) ?? "";
+            }
+            catch
+            {
+                dir = "";
+            }
+            if (string.IsNullOrWhiteSpace(dir))
+                dir = AppContext.BaseDirectory;
+
+            var path = Path.Combine(dir, "DeviceSettings.config");
+            if (!File.Exists(path))
+                return;
+
+            try
+            {
+                var raw = File.ReadAllText(path);
+                var serializer = new DataContractJsonSerializer(typeof(DeviceSettingsFile));
+                DeviceSettingsFile? overlay;
+                using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(raw)))
+                    overlay = serializer.ReadObject(ms) as DeviceSettingsFile;
+                if (overlay == null)
+                    return;
+
+                if (!string.IsNullOrWhiteSpace(overlay.MachineScopeMode))
+                    cfg.MachineScopeMode = overlay.MachineScopeMode;
+                if (overlay.ScopedMachineIps != null)
+                    cfg.ScopedMachineIps = new List<string>(overlay.ScopedMachineIps);
+                cfg.EnableTemplateDeviceToDbSync = overlay.EnableTemplateDeviceToDbSync;
+                cfg.EnableTemplateDbToDeviceSync = overlay.EnableTemplateDbToDeviceSync;
+                if (overlay.SourceMachineIp != null)
+                    cfg.SourceMachineIp = overlay.SourceMachineIp;
+                if (overlay.TargetMachineIps != null)
+                    cfg.TargetMachineIps = new List<string>(overlay.TargetMachineIps);
+                if (overlay.SyncEmployeeIds != null)
+                    cfg.SyncEmployeeIds = new List<string>(overlay.SyncEmployeeIds);
+            }
+            catch
+            {
+                // Keep serviceconfig / defaults if DeviceSettings.config cannot be parsed.
+            }
+        }
+
         private static void NormalizeLoadedDeviceConfig(HikvisionServiceConfig? cfg)
         {
             if (cfg == null)
@@ -524,6 +586,32 @@ public sealed class HikvisionAttendanceWindowsService : ServiceBase
         }
     }
 
+    /// <summary>Device-scope and template-direction settings loaded from DeviceSettings.config.</summary>
+    [DataContract]
+    internal sealed class DeviceSettingsFile
+    {
+        [DataMember]
+        public string MachineScopeMode { get; set; } = "CENTRAL";
+
+        [DataMember]
+        public List<string> ScopedMachineIps { get; set; } = new List<string>();
+
+        [DataMember]
+        public bool EnableTemplateDeviceToDbSync { get; set; }
+
+        [DataMember]
+        public bool EnableTemplateDbToDeviceSync { get; set; }
+
+        [DataMember]
+        public string SourceMachineIp { get; set; } = "";
+
+        [DataMember]
+        public List<string> TargetMachineIps { get; set; } = new List<string>();
+
+        [DataMember]
+        public List<string> SyncEmployeeIds { get; set; } = new List<string>();
+    }
+
     /// <summary>Policies for multi-device user/face sync (ISAPI). Loaded from service JSON only.</summary>
     [DataContract]
     internal sealed class UserSyncPoliciesConfig