Result classes can derive when new instance is created.

DotBased.ASP.Auth/Services/AuthService.cs

@@ -1,5 +1,6 @@
 using DotBased.ASP.Auth.Domains;
 using DotBased.ASP.Auth.Domains.Auth;
+using DotBased.ASP.Auth.Domains.Identity;
 using DotBased.Extensions;
 using DotBased.Logging;
 
@@ -7,22 +8,44 @@ namespace DotBased.ASP.Auth.Services;
 
 public class AuthService
 {
-    public AuthService(AuthDataCache dataCache)
+    public AuthService(IAuthDataRepository authDataRepository, AuthDataCache dataCache)
     {
+        _authDataRepository = authDataRepository;
         _dataCache = dataCache;
         _logger = LogService.RegisterLogger(typeof(AuthService));
     }
 
+    private readonly IAuthDataRepository _authDataRepository;
     private readonly AuthDataCache _dataCache;
     private readonly ILogger _logger;
 
     public async Task<Result<AuthenticationStateModel>> LoginAsync(LoginModel login)
     {
-        if (login.UserName.IsNullOrWhiteSpace())
-            return Result<AuthenticationStateModel>.Failed("Username argument is empty!");
-        //var userResult = await _dataProvider.GetUserAsync(string.Empty, login.Email, login.UserName);
-        //TODO: validate user password and create a session state
-        return Result<AuthenticationStateModel>.Failed("");
+        UserModel? user = null;
+        Result<UserModel> usrResult;
+        if (!login.UserName.IsNullOrWhiteSpace())
+        {
+            usrResult = await _authDataRepository.GetUserAsync(string.Empty, string.Empty, login.UserName);
+            if (usrResult is { Success: true, Value: not null })
+                user = usrResult.Value;
+        }
+        else if (!login.Email.IsNullOrWhiteSpace())
+        {
+            usrResult = await _authDataRepository.GetUserAsync(string.Empty, login.Email, string.Empty);
+            if (usrResult is { Success: true, Value: not null })
+                user = usrResult.Value;
+        }
+        else
+            return Result<AuthenticationStateModel>.Failed("Username & Email is empty, cannot login!");
+
+        if (user == null || !usrResult.Success)
+            return new Result<AuthenticationStateModel>(usrResult);
+
+        if (user.PasswordHash != login.Password) //TODO: Hash password and compare
+            return Result<AuthenticationStateModel>.Failed("Login failed, invalid password.");
+        var state = new AuthenticationStateModel(user);
+        await _authDataRepository.CreateAuthenticationStateAsync(state);
+        return Result<AuthenticationStateModel>.Ok(state);
     }
 
     public async Task<Result> Logout(string state)