simplyfy null checks

OwnChar/Data/IDataManager.cs

@@ -9,7 +9,7 @@ public interface IDataManager
     abstract bool Logout(UserAccount? account);
 
     // User management
-    abstract UserAccount? CreateUserAccount(string username, string password);
+    abstract UserAccount? CreateUserAccount(UserAccount account, string username, string password);
     abstract UserProfile? GetUserProfile(UserAccount account);
     abstract bool DeleteUserAccount(UserAccount account);
 

OwnChar/Manager/CharacterManager.cs

@@ -11,7 +11,7 @@ public class CharacterManager(OwnCharManager manager)
         Manager.CheckLogin();
 
         if (group != null)
-            return Manager.DataManager?.GetCharacters(Manager.CurrentUser!, group);
+            return Manager.DataManager.GetCharacters(Manager.CurrentUser, group);
 
         return null;
     }
@@ -21,7 +21,7 @@ public class CharacterManager(OwnCharManager manager)
         Manager.CheckLogin();
 
         if (profile != null)
-            return Manager.DataManager?.GetCharacters(Manager.CurrentUser!, profile);
+            return Manager.DataManager.GetCharacters(Manager.CurrentUser, profile);
 
         return null;
     }
@@ -34,18 +34,14 @@ public class CharacterManager(OwnCharManager manager)
     public Character? CreateCharacter(string? name, Group? destination)
     {
         ArgumentException.ThrowIfNullOrWhiteSpace(name, nameof(name));
-        
         Manager.CheckLogin();
-
-        return Manager.DataManager?.CreateCharacter(Manager.CurrentUser!, name, destination);
+        return Manager.DataManager.CreateCharacter(Manager.CurrentUser, name, destination);
     }
 
     public bool DeleteCharacter(Character? character)
     {
         ArgumentNullException.ThrowIfNull(character, nameof(character));
-
         Manager.CheckLogin();
-
-        return Manager.DataManager?.DeleteCharacter(Manager.CurrentUser!, character) ?? false;
+        return Manager.DataManager.DeleteCharacter(Manager.CurrentUser, character);
     }
 }

OwnChar/Manager/GroupsManager.cs

@@ -9,42 +9,44 @@ public class GroupsManager(OwnCharManager manager)
     public UserProfile? GetOwner(Group? group)
     {
         ArgumentNullException.ThrowIfNull(group, nameof(group));
-        return Manager.DataManager?.GetOwner(Manager.CurrentUser!, group);
+        Manager.CheckLogin();
+        return Manager.DataManager.GetOwner(Manager.CurrentUser, group);
     }
 
     public IEnumerable<UserProfile>? GetMembers(Group? group)
     {
         ArgumentNullException.ThrowIfNull(group, nameof(group));
-        return Manager.DataManager?.GetMembers(Manager.CurrentUser!, group);
+        Manager.CheckLogin();
+        return Manager.DataManager.GetMembers(Manager.CurrentUser, group);
     }
 
     public bool AddMember(UserProfile? profile, Group? group)
     {
-        Manager.CheckLogin();
         ArgumentNullException.ThrowIfNull(profile, nameof(profile));
         ArgumentNullException.ThrowIfNull(group, nameof(group));
-        return Manager.DataManager?.AddMember(Manager.CurrentUser!, group, profile) ?? false;
+        Manager.CheckLogin();
+        return Manager.DataManager.AddMember(Manager.CurrentUser, group, profile);
     }
 
     public bool DeleteMember(UserProfile? profile, Group? group)
     {
-        Manager.CheckLogin();
         ArgumentNullException.ThrowIfNull(profile, nameof(profile));
         ArgumentNullException.ThrowIfNull(group, nameof(group));
-        return Manager.DataManager?.RemoveMember(Manager.CurrentUser!, group, profile) ?? false;
+        Manager.CheckLogin();
+        return Manager.DataManager.RemoveMember(Manager.CurrentUser, group, profile);
     }
 
     public Group? CreateGroup(string? name)
     {
-        Manager.CheckLogin();
         ArgumentException.ThrowIfNullOrWhiteSpace(name, nameof(name));
-        return Manager.DataManager?.CreateGroup(Manager.CurrentUser!, name);
+        Manager.CheckLogin();
+        return Manager.DataManager.CreateGroup(Manager.CurrentUser, name);
     }
 
     public bool DeleteGroup(Group? group)
     {
-        Manager.CheckLogin();
         ArgumentNullException.ThrowIfNull(group, nameof(group));
-        return Manager.DataManager?.DeleteGroup(Manager.CurrentUser!, group) ?? false;
+        Manager.CheckLogin();
+        return Manager.DataManager.DeleteGroup(Manager.CurrentUser, group);
     }
 }

OwnChar/Manager/OwnCharManager.cs

@@ -2,13 +2,14 @@
 using OwnChar.Manager.Exceptions;
 using OwnChar.Model;
 using Pilz.Cryptography;
+using System.Diagnostics.CodeAnalysis;
 
 namespace OwnChar.Manager;
 
 public class OwnCharManager
 {
     // User
-    public bool IsLoggedIn => CurrentUser != null;
+    public bool IsLoggedIn => CurrentUser != null && DataManager != null;
     public UserAccount? CurrentUser { get; private set; }
 
     // Data Provider
@@ -26,6 +27,7 @@ public class OwnCharManager
         Characters = new(this);
     }
 
+    [MemberNotNull(nameof(CurrentUser), nameof(DataManager))]
     internal protected void CheckLogin()
     {
         if (!IsLoggedIn)
@@ -36,6 +38,7 @@ public class OwnCharManager
     /// Tries to login on the given data provider.
     /// </summary>
     /// <returns>Returns <see cref="true"/> if the login was successfull and <see cref="false"/> if not.</returns>
+    [MemberNotNullWhen(true, nameof(CurrentUser), nameof(DataManager))]
     public bool Login(IDataManager? proxy, string? username, SecureString? password)
     {
         ArgumentNullException.ThrowIfNull(proxy, nameof(proxy));

OwnChar/Manager/UserManager.cs

@@ -10,20 +10,22 @@ public class UserManager(OwnCharManager manager)
     public UserProfile? GetOwnUserProfile()
     {
         Manager.CheckLogin();
-        return Manager.DataManager!.GetUserProfile(Manager.CurrentUser!);
+        return Manager.DataManager.GetUserProfile(Manager.CurrentUser);
     }
 
     public UserAccount? CreateUserAccount(string? username, SecureString? password)
     {
         ArgumentException.ThrowIfNullOrWhiteSpace(username, nameof(username));
         ArgumentException.ThrowIfNullOrWhiteSpace(password, nameof(password));
+        Manager.CheckLogin();
         username = username.Trim().ToLower();
-        return Manager.DataManager?.CreateUserAccount(username, Utils.HashPassword(username, password));
+        return Manager.DataManager.CreateUserAccount(Manager.CurrentUser, username, Utils.HashPassword(username, password));
     }
 
     public bool DeleteUserAccount(UserAccount? account)
     {
         ArgumentNullException.ThrowIfNull(account, nameof(account));
-        return Manager.DataManager?.DeleteUserAccount(account) ?? false;
+        Manager.CheckLogin();
+        return Manager.DataManager.DeleteUserAccount(account);
     }
 }