Merge branch 'master' of http://git2.aycode.com/Adam/TourIAm

TIAM.Services/SignalRTags.cs

@@ -5,7 +5,7 @@ namespace TIAM.Services;
 
 public class SignalRTags : AcSignalRTags
 {
-    public const int GetSiteViewModelByUserId = 999;
+    public const int GetSiteViewModelByUserId = int.MaxValue;
 
     public const int GetTransfer = 1;
     public const int GetTransfers = 2;
@@ -132,5 +132,8 @@ public class SignalRTags : AcSignalRTags
     public const int DriverUpdateTransfer = 151;
 
     public const int AuthenticateUser = 160;
+    public const int RefreshToken = 200;
+
+
     public const int GetAllLogItemsByFilterText = 1000;
 }

TIAMSharedUI/Pages/AppLaunchComponent.razor

@@ -11,6 +11,7 @@
 @using AyCode.Interfaces.StorageHandlers;
 @using System.Globalization;
 @using AyCode.Core.Enums
+@using AyCode.Core.Extensions
 @using AyCode.Core.Helpers
 @using AyCode.Core.Loggers
 @using AyCode.Services.Loggers
@@ -104,7 +105,7 @@
                 else
                 {
                     _logger.Info("Couldn't refresh token");
-                    SignOut();
+                    await SignOut();
                     //NavManager.NavigateTo("/");
                     return;
                 }
@@ -210,14 +211,19 @@
         return (userDetailsStr, locale);
     }
 
-    private void SignOut()
+    private async Task SignOut()
     {
-        var userBasicDetail = JsonConvert.DeserializeObject<UserBasicDetails>(userDetailsStr);
+        _logger.Info("SignOut called");
 
-        UserDataService.Logout(userBasicDetail?.RefreshToken);
+        var userBasicDetail = userDetailsStr.JsonTo<UserBasicDetails>();
-        AuthStateProvider.GetAuthenticationStateAsync();
+
-        SecureStorageHandler.ClearAllSecureStorageAsync();
+        await AuthStateProvider.GetAuthenticationStateAsync();
+        await SecureStorageHandler.ClearAllSecureStorageAsync();
+        
         sessionService.ClearAll();
+        ComponentUpdateService.CallRequestRefreshAll();
+
+        UserDataService.Logout(userBasicDetail?.RefreshToken).Forget();
     }
 
     CultureInfo Culture

TIAMSharedUI/Pages/Login.razor.cs

@@ -94,23 +94,22 @@ namespace TIAMSharedUI.Pages
                 }
                 else
                 {
-                    string authResponseJson = mainResponse.Content.ToJson(); //JsonSerializer.Serialize(mainResponse.Content);
+                    //var authResponseJson = mainResponse.Content.ToJson(); //JsonSerializer.Serialize(mainResponse.Content);
+                    var authResponse = mainResponse.Content.ToJson().JsonTo<AuthenticationTokens>(); //JsonSerializer.Deserialize<AuthenticationResponse>(authResponseJson, new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
 
-                    var authResponse = authResponseJson.JsonTo<AuthenticationResponse>(); //JsonSerializer.Deserialize<AuthenticationResponse>(authResponseJson, new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
+                    var accessToken = authResponse.AccessToken;
-
-                    string accessToken = authResponse.AccessToken;
 
                     var token = ProcessToken(accessToken);
 
-                    string userId = token.Claims.First(claim => claim.Type == JwtRegisteredClaimNames.NameId).Value;
+                    var userId = token.Claims.First(claim => claim.Type == JwtRegisteredClaimNames.NameId).Value;
-                    string email = token.Claims.First(claim => claim.Type == JwtRegisteredClaimNames.Email).Value;
+                    var email = token.Claims.First(claim => claim.Type == JwtRegisteredClaimNames.Email).Value;
 
                     var myId = Guid.Parse(userId);
                     //userDataService.User.Email = _email;
 
                     var userBasicDetails = new UserBasicDetails(userId, email, authResponse.AccessToken, authResponse.RefreshToken);
 
-                    string userBasicDetailsJson = JsonSerializer.Serialize(userBasicDetails);
+                    var userBasicDetailsJson = JsonSerializer.Serialize(userBasicDetails);
 
 
                     //save to local storage
@@ -193,9 +192,9 @@ namespace TIAMSharedUI.Pages
 
         public async Task<bool> CheckIfDriver(List<UserProductMapping> Permissions)
         {
-            bool _isDriver = false;
+            var _isDriver = false;
 
-            foreach (UserProductMapping Permission in Permissions)
+            foreach (var Permission in Permissions)
             {
                 //var permissionToCheck = await ServiceProviderDataService.GetUserProductMappingByIdAsync(Permission.Id);
                 BrowserConsoleLogWriter.Debug($"calling IsPowerOf with values: {Permission.Id}, {Permission.Permissions}, {1}");
@@ -213,11 +212,11 @@ namespace TIAMSharedUI.Pages
         {
             BrowserConsoleLogWriter.Debug($"called IsBitSet with values: {number}, {power}");
 
-            int powerOfTwo = 1 << power; // Calculate 2^power
+            var powerOfTwo = 1 << power; // Calculate 2^power
 
             BrowserConsoleLogWriter.Debug($"powerOfTwo: {powerOfTwo}, {power}");
 
-            bool result = (number & powerOfTwo) != 0; // Check if the bit at position `power` is set
+            var result = (number & powerOfTwo) != 0; // Check if the bit at position `power` is set
             return result;
         }
     }

TIAMSharedUI/Pages/User/Hotels/HotelAdmin.razor

@@ -1,4 +1,4 @@
-@page "/user/hoteladmin/{id:guid}"
+@page "/user/hoteladmin/{Id:guid}"
 @using TIAMSharedUI.Shared
 @using TIAMWebApp.Shared.Application.Interfaces;
 @using TIAMSharedUI.Shared.Components.BaseComponents
@@ -16,7 +16,7 @@
 
 <div class="container-fluid">
 
-    <HotelComponent Id="@id"></HotelComponent>
+    <HotelComponent Id="@Id"></HotelComponent>
     
     <!-- Stats admin-->
     <hr />
@@ -25,24 +25,19 @@
 
 
 @code {
-    [Parameter] public Guid id { get; set; }
+    [Parameter] public Guid Id { get; set; }
-    bool isUserLoggedIn;
+    bool _isUserLoggedIn;
-    int userType = 0;
+    int _userType = 0;
 
     protected override void OnInitialized()
     {
         //check if Id matches with userproductmapping
-        if (!_sessionService.IsAuthenticated)
+        if (!_sessionService.IsAuthenticated) return;
-        {
-            return;
-        }
-        var check = _sessionService.User.UserModelDto.UserProductMappings.Any(x => x.ProductId == id);
-        if (!check)
-        {
-            return;
-        }
-        base.OnInitialized();                        
 
+        var check = _sessionService.User?.UserModelDto.UserProductMappings.Any(x => x.ProductId == Id) ?? false;
+        if (!check) return;
+
+        base.OnInitialized();                        
     }
     
 }

TIAMSharedUI/Pages/User/Hotels/HotelComponent.razor.cs

@@ -15,6 +15,7 @@ using TIAMWebApp.Shared.Application.Models;
 using TIAMWebApp.Shared.Application.Models.ClientSide.UI;
 using TIAMWebApp.Shared.Application.Services;
 using TIAMWebApp.Shared.Application.Utility;
+using System.Collections.Generic;
 
 namespace TIAMSharedUI.Pages.User.Hotels
 {
@@ -148,7 +149,9 @@ namespace TIAMSharedUI.Pages.User.Hotels
                 s.Phone
             });
 
-            var productOwner = await AdminSignalRClient.GetByIdAsync<List<Company>>(SignalRTags.GetCompaniesById, _hotel.ServiceProviderId);
+            List<Company>? productOwner = null;
+            if (_hotel != null) productOwner = await AdminSignalRClient.GetByIdAsync<List<Company>>(SignalRTags.GetCompaniesById, _hotel.ServiceProviderId);
+
             if (productOwner != null)
             {
                 ImageSource = await ServiceProviderDataService.GetQRCodeByProductIdAsync(productOwner[0].AffiliateId);

TIAMSharedUI/Pages/User/MyServiceProviders.razor

@@ -138,7 +138,7 @@
     //-----------------------------------------------------------------------------------
 
 
-    public async Task SubmitForm(object result)
+    public void SubmitForm(object result)
     {
         //await WizardProcessor.ProcessWizardAsync(Result.GetType(), Result);
         _logger.Info($"Submitted nested form: {result.GetType().FullName}");
@@ -162,7 +162,7 @@
         _logger = new LoggerClient<MyServiceProviders>(LogWriters.ToArray());
         var myId = SessionService.User!.UserId;
 
-        _logger.Debug(companies.Count().ToString());
+        _logger.Debug(companies.Count.ToString());
         _contextIds = new Guid[1];
         _contextIds[0] = myId;
         var result = await AdminSignalRClient.GetByIdAsync<List<Company>>(SignalRTags.GetCompaniesByContextId, myId);

TIAMSharedUI/Shared/Components/BaseComponents/BasePageComponent.cs

@@ -58,7 +58,7 @@ namespace TIAMSharedUI.Shared.Components.BaseComponents
             var currentUrl = _navManager.ToBaseRelativePath(_navManager.Uri);
 
             _pageState.AddPageToHistory(currentUrl);
-            _logger.Debug(_pageState.GetGoBackPage());
+            //_logger.Debug(_pageState.GetGoBackPage());
         }
     }
 }

TIAMSharedUI/Shared/Components/Navbar.razor.cs

@@ -112,7 +112,6 @@ namespace TIAMSharedUI.Shared.Components
 
         protected override void OnInitialized()
         {
-
             base.OnInitialized();
             navigationManager.LocationChanged += OnLocationChanged;
             _logger = new LoggerClient<Navbar>(LogWriters.ToArray());
@@ -120,7 +119,7 @@ namespace TIAMSharedUI.Shared.Components
 
             _logger.Debug($"Navbar OnInit {DateTime.Now} ");
 
-            InitUser();
+            if (sessionService.IsAuthenticated) InitUser();
         }
 
         private void OnLocationChanged(object sender, LocationChangedEventArgs e)
@@ -157,6 +156,7 @@ namespace TIAMSharedUI.Shared.Components
                 myUser = true;
                 userId = sessionService.User.UserId;
                 userEmail = sessionService.User.Email;
+
                 if (sessionService.User.UserModelDto.ProfileDto.FullName != null)
                 {
                     userFullName = sessionService.User.UserModelDto.ProfileDto.FullName!;
@@ -169,15 +169,13 @@ namespace TIAMSharedUI.Shared.Components
             }
 
             var properties = sessionService.User?.HasProperties;
-
+            if (properties == null) return;
-            if (properties == null)
+            
-                return;
-
-
             hasProperty = properties.Count > 0;
             isSysAdmin = sessionService.IsSysAdmin;
             isDevAdmin = sessionService.IsDevAdmin;
             isDriver = sessionService.IsDriver;
+
             foreach (var property in properties)
             {
                 _logger.Detail($"First property: {property.Value} ");

TIAMWebApp/Server/Controllers/UserAPIController.cs

@@ -26,6 +26,7 @@ using TIAM.Services.Server.Logins;
 using TIAMWebApp.Server.Services;
 using AyCode.Core.Enums;
 using AyCode.Models.Enums;
+using AyCode.Utils.Extensions;
 using TIAM.Models;
 
 namespace TIAMWebApp.Server.Controllers
@@ -119,7 +120,7 @@ namespace TIAMWebApp.Server.Controllers
 
             var response = new MainResponse
             {
-                Content = new AuthenticationResponse
+                Content = new AuthenticationTokens
                 {
                     RefreshToken = loggedInModel.LoggedInUser.RefreshToken,
                     AccessToken = loggedInModel.AccessToken
@@ -135,16 +136,87 @@ namespace TIAMWebApp.Server.Controllers
         [AllowAnonymous]
         [HttpPost]
         [Route(APIUrls.RefreshTokenRouteName)]
-        public async Task<IActionResult> RefreshToken(RefreshTokenRequest? refreshTokenRequest)
+        public async Task<IActionResult> RefreshToken(AuthenticationTokens? refreshTokenRequest)
         {
-            _logger.Info(@"RefreshToken called");
+            var mainResponse = await RefreshTokenSignalR(refreshTokenRequest);
+
+            return mainResponse.IsSuccess ? Ok(mainResponse) : BadRequest(mainResponse);
+
+            //_logger.Info(@"RefreshToken called");
+
+            //var response = new MainResponse();
+            //if (refreshTokenRequest is null)
+            //{
+            //    _logger.Info(@"RefreshTokenRequest is null");
+
+            //    response.ErrorMessage = "Invalid request";
+            //    return BadRequest(response);
+            //}
+
+            //var principal = _loginService.GetPrincipalFromExpiredToken(refreshTokenRequest.AccessToken);
+
+            //if (principal != null)
+            //{
+            //    _logger.Info(@"Principal is not null");
+            //    var email = principal.Claims.FirstOrDefault(f => f.Type == ClaimTypes.Email);
+
+            //    //var userModel = await _userManager.FindByEmailAsync(email?.Value);
+            //    //UserModel? user = users.FirstOrDefault(x => x.Email == email?.Value);
+            //    User? dbUser = null;
+
+            //    if (email != null)
+            //    {
+            //        //get user from db
+            //        dbUser = await userDal.GetUserByEmailAsync(email.Value, true);
+            //        _logger.Info($@"DbUser email: {dbUser?.EmailAddress}");
+            //    }
+
+            //    //mocking - update userModel with new refreshToken so it returns true after the check below
+            //    //dbUser.RefreshToken = refreshTokenRequest.RefreshToken;
+
+            //    if (dbUser is null || dbUser.RefreshToken != refreshTokenRequest.RefreshToken)
+            //    {
+            //        response.ErrorMessage = "Invalid Request";
+            //        _logger.Info($@"{dbUser?.RefreshToken}, {refreshTokenRequest.RefreshToken}");
+
+            //        return BadRequest(response);
+            //    }
+
+            //    var newAccessToken = _loginService.GenerateAccessToken(dbUser);
+            //    var refreshToken = _loginService.GenerateRefreshToken();
+
+            //    //mocking - update userModel with new refreshToken
+            //    dbUser.RefreshToken = refreshToken;
+            //    //TODO await _userManager.UpdateAsync(userModel);
+            //    await userDal.UpdateJwtRefreshTokenAsync(dbUser.EmailAddress, dbUser.RefreshToken);
+
+            //    response.IsSuccess = true;
+            //    response.Content = new AuthenticationResponse
+            //    {
+            //        RefreshToken = refreshToken,
+            //        AccessToken = newAccessToken
+            //    };
+
+            //    return Ok(response);
+            //}
+
+            //_logger.Info(@"Principal is null");
+            //return NotFound("Invalid Token Found");
+        }
+
+        [NonAction]
+        [SignalR(SignalRTags.RefreshToken)]
+        public async Task<MainResponse> RefreshTokenSignalR(AuthenticationTokens? refreshTokenRequest)
+        {
+            _logger.Info("RefreshToken called");
 
             var response = new MainResponse();
             if (refreshTokenRequest is null)
             {
-                _logger.Info(@"RefreshTokenRequest is null");
+                _logger.Info("RefreshTokenRequest is null");
-                response.ErrorMessage = "Invalid  request";
+
-                return BadRequest(response);
+                response.ErrorMessage = "Invalid request";
+                return response;
             }
 
             var principal = _loginService.GetPrincipalFromExpiredToken(refreshTokenRequest.AccessToken);
@@ -152,49 +224,43 @@ namespace TIAMWebApp.Server.Controllers
             if (principal != null)
             {
                 _logger.Info(@"Principal is not null");
-                var email = principal.Claims.FirstOrDefault(f => f.Type == ClaimTypes.Email);
 
-                //var userModel = await _userManager.FindByEmailAsync(email?.Value);
-                //UserModel? user = users.FirstOrDefault(x => x.Email == email?.Value);
                 User? dbUser = null;
 
-                if (email != null)
+                var emailClaim = principal.Claims.FirstOrDefault(f => f.Type == ClaimTypes.Email);
+                if (emailClaim != null) dbUser = await userDal.GetUserByEmailAsync(emailClaim.Value, true);
+
+                if (dbUser is null || refreshTokenRequest.RefreshToken.IsNullOrWhiteSpace() || dbUser.RefreshToken != refreshTokenRequest.RefreshToken)
                 {
-                    //get user from db
+                    response.ErrorMessage = "User not found or RefreshToken is not valid!";
-                    dbUser = await userDal.GetUserByEmailAsync(email.Value, true);
+                    _logger.Info($"{response.ErrorMessage}; dbUser.RefreshToken: {dbUser?.RefreshToken}, refreshTokenRequest.RefreshToken: {refreshTokenRequest.RefreshToken}");
-                    _logger.Info($@"DbUser email: {dbUser?.EmailAddress}");
+
+                    return response;
                 }
 
-                //mocking - update userModel with new refreshToken so it returns true after the check below
+                _logger.Info($"DbUser email: {dbUser.EmailAddress}");
-                //dbUser.RefreshToken = refreshTokenRequest.RefreshToken;
-
-                if (dbUser is null || dbUser.RefreshToken != refreshTokenRequest.RefreshToken)
-                {
-                    response.ErrorMessage = "Invalid Request";
-                    _logger.Info($@"{dbUser?.RefreshToken}, {refreshTokenRequest.RefreshToken}");
-                    return BadRequest(response);
-                }
 
                 var newAccessToken = _loginService.GenerateAccessToken(dbUser);
                 var refreshToken = _loginService.GenerateRefreshToken();
 
-                //mocking - update userModel with new refreshToken
                 dbUser.RefreshToken = refreshToken;
-                //TODO await _userManager.UpdateAsync(userModel);
                 await userDal.UpdateJwtRefreshTokenAsync(dbUser.EmailAddress, dbUser.RefreshToken);
 
-                response.IsSuccess = true;
+                response.Content = new AuthenticationTokens
-                response.Content = new AuthenticationResponse
                 {
                     RefreshToken = refreshToken,
                     AccessToken = newAccessToken
                 };
 
-                return Ok(response);
+                response.IsSuccess = true;
             }
-
+            else
-            _logger.Info(@"Principal is null");
+            {
-            return NotFound("Invalid Token Found");
+                _logger.Info($"Principal is null! AccessToken: {refreshTokenRequest.AccessToken}");
+                response.ErrorMessage = "Principal is null";
+            }
+            
+            return response;
         }
 
         [AllowAnonymous]

TIAMWebApp/Server/Models/RefreshTokenRequest.cs

@@ -1,8 +0,0 @@
-namespace TIAMWebApp.Server.Models
-{
-    public class RefreshTokenRequest
-    {
-        public string AccessToken { get; set; }
-        public string RefreshToken { get; set; }
-    }
-}

TIAMWebApp/Shared/Models/AuthenticateRequestAndResponse.cs

@@ -1,9 +0,0 @@
-
-namespace TIAMWebApp.Shared.Application.Models
-{
-    public class AuthenticateRequestAndResponse
-    {
-        public string AccessToken { get; set; }
-        public string RefreshToken { get; set; }
-    }
-}

TIAMWebApp/Shared/Models/AuthenticationTokens.cs

@@ -1,6 +1,6 @@
 namespace TIAMWebApp.Shared.Application.Models
 {
-    public class AuthenticationResponse
+    public class AuthenticationTokens
     {
         public string? AccessToken { get; set; }
         public string? RefreshToken { get; set; }

TIAMWebApp/Shared/Models/ClientSide/UI/TransferStatusModel.cs

@@ -2,16 +2,10 @@
 
 namespace TIAMWebApp.Shared.Application.Models.ClientSide.UI
 {
-    public class TransferStatusModel
+    public class TransferStatusModel(TransferStatusType statusValue, string statusName)
     {
-        public TransferStatusType StatusValue { get; set; }
+        public TransferStatusType StatusValue { get; set; } = statusValue;
-        public string StatusName { get; set; }
+        public string StatusName { get; set; } = statusName;
-
-        public TransferStatusModel(TransferStatusType statusValue, string statusName)
-        {
-            StatusValue = statusValue;
-            StatusName = statusName;
-        }
 
         public static TransferStatusModel GetStatusModel(TransferStatusType transferStatusType)
             => AllStatuses[transferStatusType];

TIAMWebApp/Shared/Services/UserDataServiceClientBase.cs

@@ -1,8 +1,10 @@
 using System.Net.Http.Json;
 using System.Text;
 using System.Text.Json;
+using AyCode.Core.Extensions;
 using AyCode.Interfaces.StorageHandlers;
 using AyCode.Services.Loggers;
+using Microsoft.IdentityModel.Tokens;
 using Newtonsoft.Json;
 using TIAM.Models.Dtos.Users;
 using TIAM.Services;
@@ -265,38 +267,40 @@ public abstract class UserDataServiceClientBase : IUserDataService
         Logger.Debug("RefreshToken() called");
 
         var isTokenRefreshed = false;
-        var url = $"{Setting.ApiBaseUrl}/{APIUrls.RefreshToken}";
+        MainResponse? mainResponse = null;
-        //var url = APIUrls.RefreshToken;                
-
-        var serializedStr = JsonConvert.SerializeObject(new AuthenticateRequestAndResponse
-        {
-            RefreshToken = Setting.UserBasicDetails.RefreshToken,
-            AccessToken = Setting.UserBasicDetails.AccessToken
-        });
 
         try
         {
-            Logger.Debug("Refreshtoken url: " + url);
+            var postAuthenticationTokens = new AuthenticationTokens
-            var response = await Http.PostAsync(url, new StringContent(serializedStr, Encoding.UTF8, "application/json"));
-            if (response.IsSuccessStatusCode)
             {
-                var contentStr = await response.Content.ReadAsStringAsync();
+                RefreshToken = Setting.UserBasicDetails.RefreshToken,
-                var mainResponse = JsonConvert.DeserializeObject<MainResponse>(contentStr);
+                AccessToken = Setting.UserBasicDetails.AccessToken
-                if (mainResponse.IsSuccess)
+            };
+
+            mainResponse = await AdminSignalRClient.PostDataAsync<AuthenticationTokens, MainResponse>(SignalRTags.RefreshToken, postAuthenticationTokens);
+
+            if (mainResponse is { IsSuccess: true })
+            {
+                var tokenDetails = mainResponse.Content.ToJson().JsonTo<AuthenticationTokens>();
+                if (tokenDetails == null || string.IsNullOrWhiteSpace(tokenDetails.AccessToken) || string.IsNullOrWhiteSpace(tokenDetails.RefreshToken))
+                {
+                    Logger.Error($"Refreshtoken error! tokenDetails == null || string.IsNullOrWhiteSpace(tokenDetails.AccessToken) || string.IsNullOrWhiteSpace(tokenDetails.RefreshToken); AccessToken: {tokenDetails?.AccessToken}; RefreshToken: {tokenDetails?.RefreshToken}");
+                }
+                else
                 {
-                    var tokenDetails = JsonConvert.DeserializeObject<AuthenticateRequestAndResponse>(mainResponse.Content.ToString());
                     Setting.UserBasicDetails.AccessToken = tokenDetails.AccessToken;
                     Setting.UserBasicDetails.RefreshToken = tokenDetails.RefreshToken;
 
-                    var userDetailsStr = JsonConvert.SerializeObject(Setting.UserBasicDetails);
+                    var userDetailsStr = Setting.UserBasicDetails.ToJson(); //JsonConvert.SerializeObject(Setting.UserBasicDetails);
                     await SecureStorageHandler.SaveToSecureStorageAsync(nameof(Setting.UserBasicDetails), userDetailsStr);
                     isTokenRefreshed = true;
                 }
             }
+            else Logger.Info($"Refreshtoken is not success! {mainResponse?.ErrorMessage ?? "mainResponse == null"}");
         }
         catch (Exception ex)
         {
-            Logger.Error("Refreshtoken exception: " + ex.Message, ex);
+            Logger.Error($"Refreshtoken, {mainResponse?.ErrorMessage ?? "mainResponse == null"}! exception: {ex.Message}", ex);
         }
 
         return isTokenRefreshed;

TIAMWebApp/Shared/Utility/PageHistoryState.cs

@@ -15,12 +15,18 @@ namespace TIAMWebApp.Shared.Application.Utility
 
         public void AddPageToHistory(string pageUrl)
         {
+            if (_previousPages.Count > 0 && _previousPages[^1] == pageUrl) return;
+
             _previousPages.Add(pageUrl);
         }
 
         public string GetGoBackPage()
         {
-            return _previousPages.Count > 1 ? _previousPages[^2] : _previousPages.FirstOrDefault() ?? string.Empty;
+            if (_previousPages.Count == 0) return string.Empty;
+
+            _previousPages.RemoveAt(_previousPages.Count - 1);
+
+            return _previousPages.Count > 0 ? _previousPages[^1] : string.Empty;
         }
 
         public bool CanGoBack()