App.xaml.cs

@@ -55,10 +55,10 @@ public partial class App : Application
         NavigationService navigationService = null!;
         navigationService = new NavigationService(
             session,
-            () => new AdminLoginViewModel(authService, session, navigationService, configService, adminAuditService),
+            () => new AdminLoginViewModel(authService, session, navigationService, configService, adminAuditService, employeeLookupService),
             () => new ScannerDashboardViewModel(rfidService, navigationService, session, configService, menuLookupService, employeePhotoService),
             () => new MainDashboardViewModel(navigationService, rfidService, configService, session),
-            () => new AdminSettingsAuthViewModel(authService, session, navigationService, configService),
+            () => new AdminSettingsAuthViewModel(authService, session, navigationService, configService, employeeLookupService),
             () => new SettingsViewModel(configService, navigationService, adminAuditService, syncService),
             () => new MealSchedulesViewModel(mealScheduleService, navigationService, configService));
 

Services/AuthResult.cs

@@ -6,4 +6,3 @@ namespace UtopiaCanteenSystem.Services;
 public readonly record struct AuthResult(
     bool Success,
     string EmployeeId);
-

Services/AuthService.cs

@@ -53,4 +53,3 @@ public class AuthService : IAuthService
         }
     }
 }
-

Services/ConfigService.cs

@@ -105,6 +105,16 @@ public class ConfigService : IConfigService
         SaveConfig();
     }
 
+    public void ApplyLocationSiteIdFromAuth(string? locationSiteId)
+    {
+        if (string.IsNullOrWhiteSpace(locationSiteId))
+            return;
+        var digits = new string(locationSiteId.Where(char.IsDigit).ToArray());
+        if (string.IsNullOrEmpty(digits))
+            return;
+        SetSiteId("SITE : " + digits);
+    }
+
     public string GetDeviceId()
     {
         //var id = _config.DeviceId ?? string.Empty;

Services/EmployeeLookupService.cs

@@ -72,6 +72,39 @@ public class EmployeeLookupService : IEmployeeLookupService
         };
     }
 
+    /// <inheritdoc />
+    public async Task<string?> GetLocationSiteIdByEmployeeSerialAsync(string employeeSerial, CancellationToken cancellationToken = default)
+    {
+        var serial = employeeSerial?.Trim() ?? string.Empty;
+        if (string.IsNullOrEmpty(serial))
+            return null;
+
+        var connectionString = _configService.GetHrmsLookupConnectionString();
+        if (string.IsNullOrWhiteSpace(connectionString))
+            return null;
+
+        const string sql = @"
+            SELECT location_site_id
+            FROM employee
+            WHERE serial_number = @serial
+            LIMIT 1";
+
+        await using var conn = new MySqlConnection(connectionString);
+        await conn.OpenAsync(cancellationToken).ConfigureAwait(false);
+        await using var cmd = new MySqlCommand(sql, conn);
+        cmd.Parameters.AddWithValue("@serial", serial);
+
+        await using var reader = await cmd.ExecuteReaderAsync(cancellationToken).ConfigureAwait(false);
+        if (!await reader.ReadAsync(cancellationToken).ConfigureAwait(false))
+            return null;
+
+        if (reader.IsDBNull(0))
+            return null;
+
+        var raw = reader.GetValue(0)?.ToString()?.Trim();
+        return string.IsNullOrEmpty(raw) ? null : raw;
+    }
+
     private static string GetString(MySqlDataReader reader, int ordinal)
     {
         if (reader.IsDBNull(ordinal)) return string.Empty;

Services/IConfigService.cs

@@ -25,6 +25,8 @@ public interface IConfigService
 
     string GetSiteId();
     void SetSiteId(string siteId);
+    /// <summary>Persist HRMS location_site_id in the same format as the scanner dashboard (digits → "SITE : …").</summary>
+    void ApplyLocationSiteIdFromAuth(string? locationSiteId);
     string GetDeviceId();
     void SetDeviceId(string deviceId);
 

Services/IEmployeeLookupService.cs

@@ -12,4 +12,9 @@ public interface IEmployeeLookupService
     /// Finds employee by RFID. Returns null if card is not registered in HRMS.
     /// </summary>
     Task<HrmsEmployeeInfo?> GetEmployeeByRfidAsync(string rfid, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Reads <c>employee.location_site_id</c> where <c>employee.serial_number</c> matches the login employee id. Null if missing or not configured.
+    /// </summary>
+    Task<string?> GetLocationSiteIdByEmployeeSerialAsync(string employeeSerial, CancellationToken cancellationToken = default);
 }

ViewModels/AdminLoginViewModel.cs

@@ -11,6 +11,7 @@ public partial class AdminLoginViewModel : ObservableObject
     private readonly INavigationService _navigation;
     private readonly IConfigService _config;
     private readonly IAdminAuditService _adminAudit;
+    private readonly IEmployeeLookupService _employeeLookup;
 
     [ObservableProperty]
     private string _username = string.Empty;
@@ -33,13 +34,15 @@ public partial class AdminLoginViewModel : ObservableObject
         AppSession session,
         INavigationService navigation,
         IConfigService config,
-        IAdminAuditService adminAudit)
+        IAdminAuditService adminAudit,
+        IEmployeeLookupService employeeLookup)
     {
         _authService = authService;
         _session = session;
         _navigation = navigation;
         _config = config;
         _adminAudit = adminAudit;
+        _employeeLookup = employeeLookup;
 
         RememberCredentials = _config.GetRememberAdminCredentials();
         if (RememberCredentials)
@@ -83,6 +86,16 @@ public partial class AdminLoginViewModel : ObservableObject
 
             _session.SetAdminAuthenticated(user, result.EmployeeId);
 
+            try
+            {
+                var siteId = await _employeeLookup.GetLocationSiteIdByEmployeeSerialAsync(result.EmployeeId).ConfigureAwait(true);
+                _config.ApplyLocationSiteIdFromAuth(siteId);
+            }
+            catch
+            {
+                // HRMS lookup optional; login still succeeds.
+            }
+
             // Persist who logged in (for audit / reporting).
             await _adminAudit.RecordLoginAsync(user, result.EmployeeId).ConfigureAwait(false);
 

ViewModels/AdminSettingsAuthViewModel.cs

@@ -10,6 +10,7 @@ public partial class AdminSettingsAuthViewModel : ObservableObject
     private readonly AppSession _session;
     private readonly INavigationService _navigation;
     private readonly IConfigService _config;
+    private readonly IEmployeeLookupService _employeeLookup;
 
     [ObservableProperty]
     private string _username = string.Empty;
@@ -27,12 +28,18 @@ public partial class AdminSettingsAuthViewModel : ObservableObject
     [ObservableProperty]
     private bool _rememberCredentials;
 
-    public AdminSettingsAuthViewModel(IAuthService authService, AppSession session, INavigationService navigation, IConfigService config)
+    public AdminSettingsAuthViewModel(
+        IAuthService authService,
+        AppSession session,
+        INavigationService navigation,
+        IConfigService config,
+        IEmployeeLookupService employeeLookup)
     {
         _authService = authService;
         _session = session;
         _navigation = navigation;
         _config = config;
+        _employeeLookup = employeeLookup;
 
         RememberCredentials = _config.GetRememberAdminCredentials();
         if (RememberCredentials)
@@ -83,6 +90,16 @@ public partial class AdminSettingsAuthViewModel : ObservableObject
             // Refresh session details (who authenticated for Settings).
             _session.SetAdminAuthenticated(user, result.EmployeeId);
 
+            try
+            {
+                var siteId = await _employeeLookup.GetLocationSiteIdByEmployeeSerialAsync(result.EmployeeId).ConfigureAwait(true);
+                _config.ApplyLocationSiteIdFromAuth(siteId);
+            }
+            catch
+            {
+                // HRMS lookup optional; auth still succeeds.
+            }
+
             // Persist credentials only if user opted in.
             _config.SetRememberAdminCredentials(RememberCredentials);
             if (RememberCredentials)