fix: guest user 로그인 개선

Author: ImGdevel

ProjectVG.Application/Services/Auth/AuthService.cs

@@ -39,8 +39,8 @@ public async Task<AuthResult> LoginWithOAuthAsync(string provider, string provid
 
                 if (user == null)
                 {
-                    string uuid = providerUserId.Substring(0, Math.Min(providerUserId.Length, 20));
                     // 새로운 게스트 사용자 생성
+                    string uuid = GenerateGuestUuid(providerUserId);
                     var createCommand = new UserCreateCommand(
                         Username: $"guest_{uuid}",
                         Email: $"guest@guest{uuid}.local",
@@ -139,5 +139,14 @@ public async Task<bool> LogoutAsync(string refreshToken)
             }
             return revoked;
         }
+
+        private static string GenerateGuestUuid(string providerUserId)
+        {
+            // SHA256 해시를 사용하여 일관된 UUID 생성
+            using var sha256 = System.Security.Cryptography.SHA256.Create();
+            var hash = sha256.ComputeHash(System.Text.Encoding.UTF8.GetBytes(providerUserId));
+            var hashString = Convert.ToHexString(hash);
+            return hashString.Substring(0, Math.Min(hashString.Length, 16)).ToLowerInvariant();
+        }
     }
 }

ProjectVG.Application/Services/User/IUserService.cs

@@ -10,6 +10,7 @@ public interface IUserService
         Task<UserDto?> TryGetByIdAsync(Guid userId);
         Task<UserDto?> TryGetByUidAsync(string uid);
         Task<UserDto?> TryGetByUsernameAsync(string username);
+        Task<UserDto?> TryGetByEmailAsync(string email);
         Task<UserDto?> TryGetByProviderAsync(string provider, string providerId);
 
         Task<bool> ExistsByIdAsync(Guid userId);

ProjectVG.Application/Services/User/UserService.cs

@@ -73,10 +73,15 @@ public async Task<bool> DeleteUserAsync(Guid userId)
             return user is null ? null : new UserDto(user);
         }
 
+        public async Task<UserDto?> TryGetByEmailAsync(string email)
+        {
+            var user = await _userRepository.GetByEmailAsync(email);
+            return user is null ? null : new UserDto(user);
+        }
+
         public async Task<UserDto?> TryGetByProviderAsync(string provider, string providerId)
         {
-            var users = await _userRepository.GetAllAsync();
-            var user = users.FirstOrDefault(u => u.Provider == provider && u.ProviderId == providerId);
+            var user = await _userRepository.GetByProviderAsync(provider, providerId);
             return user is null ? null : new UserDto(user);
         }
 

ProjectVG.Infrastructure/Persistence/Repositories/User/IUserRepository.cs

@@ -9,6 +9,7 @@ public interface IUserRepository
         Task<User?> GetByUsernameAsync(string username);
         Task<User?> GetByEmailAsync(string email);
         Task<User?> GetByProviderIdAsync(string providerId);
+        Task<User?> GetByProviderAsync(string provider, string providerId);
         Task<User?> GetByUIDAsync(string uid);
         Task<User> CreateAsync(User user);
         Task<User> UpdateAsync(User user);

ProjectVG.Infrastructure/Persistence/Repositories/User/SqlServerUserRepository.cs

@@ -46,6 +46,11 @@ public async Task<IEnumerable<User>> GetAllAsync()
             return await _context.Users.FirstOrDefaultAsync(u => u.ProviderId == providerId && u.Status != AccountStatus.Deleted);
         }
 
+        public async Task<User?> GetByProviderAsync(string provider, string providerId)
+        {
+            return await _context.Users.FirstOrDefaultAsync(u => u.Provider == provider && u.ProviderId == providerId && u.Status != AccountStatus.Deleted);
+        }
+
         public async Task<User?> GetByUIDAsync(string uid)
         {
             return await _context.Users.FirstOrDefaultAsync(u => u.UID == uid && u.Status != AccountStatus.Deleted);

ProjectVG.Tests/Services/Chat/Factories/ChatLLMFormatTests.cs

@@ -15,7 +15,7 @@ public ChatLLMFormatTests()
         {
             _format = new ChatLLMFormat();
 
-            var character = new CharacterDto
+            var characterEntity = new ProjectVG.Domain.Entities.Characters.Character
             {
                 Id = Guid.NewGuid(),
                 Name = "TestCharacter",
@@ -24,8 +24,12 @@ public ChatLLMFormatTests()
                 Personality = "Friendly and helpful",
                 SpeechStyle = "Casual",
                 Summary = "Character summary for testing",
-                VoiceId = "test-voice"
+                VoiceId = "test-voice",
+                IsActive = true,
+                UserAlias = "TestUser"
             };
+            
+            var character = new CharacterDto(characterEntity);
 
             var command = new ChatRequestCommand(
                 Guid.NewGuid(),