Move form state ownership from Home to leaf controls

FAQ.md

@@ -71,3 +71,7 @@ There is no separate activate button in Play. The selected character in the char
 ## Where did the Home page logic move after the refactor?
 
 `Home.razor` now focuses on composition and delegates behavior to concern-based code-behind partials (`Home.Auth.cs`, `Home.Campaign.cs`, `Home.Character.cs`, `Home.Skill.cs`, etc.) plus dedicated UI controls under `Components/Pages/HomeControls/`.
+
+## Why is auth form state kept in `AuthSection` instead of `Home`?
+
+Auth inputs and inline validation are transient UI concerns, so they now live in `AuthSection`. `Home` keeps only session/workspace state and API workflows, and returns `FormSubmissionResult` back to controls for display.

README.md

@@ -30,6 +30,7 @@ Frontend:
 - `RpgRoller/Components/Pages/Home.*.cs`: concern-based partial class split (`State`, `Lifecycle`, `Auth`, `Campaign`, `Character`, `Skill`, `Realtime`, `Api`, `Presentation`, `Validation`)
 - `RpgRoller/Components/Pages/Home.Models.cs`: reusable `FormState<TModel>` + page form models
 - `RpgRoller/Components/Pages/HomeControls/`: auth, campaign management, play-screen, and modal controls extracted from `Home.razor`
+- Form ownership model: controls own transient form/error state; `Home` receives typed submissions and returns `FormSubmissionResult` for server/business validation feedback
 - `RpgRoller/wwwroot/js/rpgroller-api.js`: browser-side API + SSE + session storage interop for Blazor
 - `RpgRoller/wwwroot/styles.css`: responsive UX styling and theme tokens
 

RpgRoller/Components/Pages/Home.Auth.cs

@@ -4,23 +4,25 @@ namespace RpgRoller.Components.Pages;
 
 public partial class Home
 {
-    private async Task RegisterAsync()
+    private async Task<FormSubmissionResult> RegisterAsync(RegisterFormModel model)
     {
-        RegisterState.ResetValidation();
+        var validationErrors = new Dictionary<string, string>();
-        var model = RegisterState.Model;
 
-        AddRequiredError(RegisterState.Errors, "username", model.Username, "Username is required.");
+        AddRequiredError(validationErrors, "username", model.Username, "Username is required.");
-        AddRequiredError(RegisterState.Errors, "displayName", model.DisplayName, "Display name is required.");
+        AddRequiredError(validationErrors, "displayName", model.DisplayName, "Display name is required.");
 
         if (string.IsNullOrWhiteSpace(model.Password) || model.Password.Length < 8)
         {
-            RegisterState.Errors["password"] = "Password must be at least 8 characters.";
+            validationErrors["password"] = "Password must be at least 8 characters.";
         }
 
-        if (RegisterState.Errors.Count > 0)
+        if (validationErrors.Count > 0)
         {
-            RegisterState.ErrorMessage = "Resolve validation issues before submitting.";
+            return new FormSubmissionResult
-            return;
+            {
+                ErrorMessage = "Resolve validation issues before submitting.",
+                Errors = validationErrors
+            };
         }
 
         IsMutating = true;
@@ -31,18 +33,23 @@ public partial class Home
                 "/api/auth/register",
                 new RegisterRequest(model.Username.Trim(), model.Password, model.DisplayName.Trim()));
 
-            model.Password = string.Empty;
             SetStatus("Registration successful. You can log in now.", false);
+            return new FormSubmissionResult();
         }
         catch (ApiRequestException ex)
         {
             if (ex.Message.Contains("already taken", StringComparison.OrdinalIgnoreCase))
             {
-                RegisterState.Errors["username"] = "Username is already taken. Choose another one.";
+                return new FormSubmissionResult
-                return;
+                {
+                    Errors = new Dictionary<string, string>
+                    {
+                        ["username"] = "Username is already taken. Choose another one."
+                    }
+                };
             }
 
-            RegisterState.ErrorMessage = ex.Message;
+            return new FormSubmissionResult { ErrorMessage = ex.Message };
         }
         finally
         {
@@ -50,18 +57,20 @@ public partial class Home
         }
     }
 
-    private async Task LoginAsync()
+    private async Task<FormSubmissionResult> LoginAsync(LoginFormModel model)
     {
-        LoginState.ResetValidation();
+        var validationErrors = new Dictionary<string, string>();
-        var model = LoginState.Model;
 
-        AddRequiredError(LoginState.Errors, "username", model.Username, "Username is required.");
+        AddRequiredError(validationErrors, "username", model.Username, "Username is required.");
-        AddRequiredError(LoginState.Errors, "password", model.Password, "Password is required.");
+        AddRequiredError(validationErrors, "password", model.Password, "Password is required.");
 
-        if (LoginState.Errors.Count > 0)
+        if (validationErrors.Count > 0)
         {
-            LoginState.ErrorMessage = "Resolve validation issues before submitting.";
+            return new FormSubmissionResult
-            return;
+            {
+                ErrorMessage = "Resolve validation issues before submitting.",
+                Errors = validationErrors
+            };
         }
 
         IsMutating = true;
@@ -72,13 +81,13 @@ public partial class Home
                 "/api/auth/login",
                 new LoginRequest(model.Username.Trim(), model.Password));
 
-            model.Password = string.Empty;
             await ReloadAuthenticatedSessionAsync(null);
             SetStatus("Logged in.", false);
+            return new FormSubmissionResult();
         }
         catch (ApiRequestException ex)
         {
-            LoginState.ErrorMessage = ex.Message;
+            return new FormSubmissionResult { ErrorMessage = ex.Message };
         }
         finally
         {

RpgRoller/Components/Pages/Home.Campaign.cs

@@ -51,18 +51,20 @@ public partial class Home
         await SyncStateEventsAsync();
     }
 
-    private async Task CreateCampaignAsync()
+    private async Task<FormSubmissionResult> CreateCampaignAsync(CampaignFormModel model)
     {
-        CampaignState.ResetValidation();
+        var validationErrors = new Dictionary<string, string>();
-        var model = CampaignState.Model;
 
-        AddRequiredError(CampaignState.Errors, "name", model.Name, "Campaign name is required.");
+        AddRequiredError(validationErrors, "name", model.Name, "Campaign name is required.");
-        AddRequiredError(CampaignState.Errors, "rulesetId", model.RulesetId, "Ruleset is required.");
+        AddRequiredError(validationErrors, "rulesetId", model.RulesetId, "Ruleset is required.");
 
-        if (CampaignState.Errors.Count > 0)
+        if (validationErrors.Count > 0)
         {
-            CampaignState.ErrorMessage = "Resolve validation issues before submitting.";
+            return new FormSubmissionResult
-            return;
+            {
+                ErrorMessage = "Resolve validation issues before submitting.",
+                Errors = validationErrors
+            };
         }
 
         IsMutating = true;
@@ -73,15 +75,15 @@ public partial class Home
                 "/api/campaigns",
                 new CreateCampaignRequest(model.Name.Trim(), model.RulesetId));
 
-            model.Name = string.Empty;
             await ReloadCampaignsAsync(campaign.Id);
             await RefreshCampaignScopeAsync();
             await SyncStateEventsAsync();
             SetStatus("Campaign created.", false);
+            return new FormSubmissionResult();
         }
         catch (ApiRequestException ex)
         {
-            CampaignState.ErrorMessage = ex.Message;
+            return new FormSubmissionResult { ErrorMessage = ex.Message };
         }
         finally
         {

RpgRoller/Components/Pages/Home.Character.cs

@@ -6,10 +6,12 @@ public partial class Home
 {
     private void OpenCreateCharacterModal()
     {
-        var model = CreateCharacterState.Model;
+        CreateCharacterInitialModel = new CharacterFormModel
-        model.Name = string.Empty;
+        {
-        model.CampaignId = SelectedCampaignId?.ToString() ?? string.Empty;
+            Name = string.Empty,
-        CreateCharacterState.ResetValidation();
+            CampaignId = SelectedCampaignId?.ToString() ?? string.Empty
+        };
+        CreateCharacterFormVersion++;
         ShowCreateCharacterModal = true;
     }
 
@@ -17,11 +19,12 @@ public partial class Home
     {
         EditingCharacterId = character.Id;
 
-        var model = EditCharacterState.Model;
+        EditCharacterInitialModel = new CharacterFormModel
-        model.Name = character.Name;
+        {
-        model.CampaignId = character.CampaignId.ToString();
+            Name = character.Name,
-
+            CampaignId = character.CampaignId.ToString()
-        EditCharacterState.ResetValidation();
+        };
+        EditCharacterFormVersion++;
         ShowEditCharacterModal = true;
     }
 
@@ -32,23 +35,25 @@ public partial class Home
         EditingCharacterId = null;
     }
 
-    private async Task CreateCharacterAsync()
+    private async Task<FormSubmissionResult> CreateCharacterAsync(CharacterFormModel model)
     {
-        CreateCharacterState.ResetValidation();
+        var validationErrors = new Dictionary<string, string>();
-        var model = CreateCharacterState.Model;
 
-        AddRequiredError(CreateCharacterState.Errors, "name", model.Name, "Character name is required.");
+        AddRequiredError(validationErrors, "name", model.Name, "Character name is required.");
         var hasCampaignId = TryParseGuid(
             model.CampaignId,
-            CreateCharacterState.Errors,
+            validationErrors,
             "campaignId",
             "Campaign is required.",
             out var campaignId);
 
-        if (CreateCharacterState.Errors.Count > 0 || !hasCampaignId)
+        if (validationErrors.Count > 0 || !hasCampaignId)
         {
-            CreateCharacterState.ErrorMessage = "Resolve validation issues before submitting.";
+            return new FormSubmissionResult
-            return;
+            {
+                ErrorMessage = "Resolve validation issues before submitting.",
+                Errors = validationErrors
+            };
         }
 
         IsMutating = true;
@@ -64,10 +69,11 @@ public partial class Home
             await RefreshCampaignScopeAsync();
             await SyncStateEventsAsync();
             SetStatus("Character created.", false);
+            return new FormSubmissionResult();
         }
         catch (ApiRequestException ex)
         {
-            CreateCharacterState.ErrorMessage = ex.Message;
+            return new FormSubmissionResult { ErrorMessage = ex.Message };
         }
         finally
         {
@@ -75,29 +81,29 @@ public partial class Home
         }
     }
 
-    private async Task UpdateCharacterAsync()
+    private async Task<FormSubmissionResult> UpdateCharacterAsync(CharacterFormModel model)
     {
-        EditCharacterState.ResetValidation();
-
         if (!EditingCharacterId.HasValue)
         {
-            EditCharacterState.ErrorMessage = "No character selected.";
+            return new FormSubmissionResult { ErrorMessage = "No character selected." };
-            return;
         }
 
-        var model = EditCharacterState.Model;
+        var validationErrors = new Dictionary<string, string>();
-        AddRequiredError(EditCharacterState.Errors, "name", model.Name, "Character name is required.");
+        AddRequiredError(validationErrors, "name", model.Name, "Character name is required.");
         var hasCampaignId = TryParseGuid(
             model.CampaignId,
-            EditCharacterState.Errors,
+            validationErrors,
             "campaignId",
             "Campaign is required.",
             out var campaignId);
 
-        if (EditCharacterState.Errors.Count > 0 || !hasCampaignId)
+        if (validationErrors.Count > 0 || !hasCampaignId)
         {
-            EditCharacterState.ErrorMessage = "Resolve validation issues before submitting.";
+            return new FormSubmissionResult
-            return;
+            {
+                ErrorMessage = "Resolve validation issues before submitting.",
+                Errors = validationErrors
+            };
         }
 
         IsMutating = true;
@@ -113,10 +119,11 @@ public partial class Home
             await RefreshCampaignScopeAsync();
             await SyncStateEventsAsync();
             SetStatus("Character updated.", false);
+            return new FormSubmissionResult();
         }
         catch (ApiRequestException ex)
         {
-            EditCharacterState.ErrorMessage = ex.Message;
+            return new FormSubmissionResult { ErrorMessage = ex.Message };
         }
         finally
         {

RpgRoller/Components/Pages/Home.Lifecycle.cs

@@ -80,10 +80,6 @@ public partial class Home
         try
         {
             Rulesets = (await RequestAsync<IReadOnlyList<RulesetDefinition>>("GET", "/api/rulesets")).ToList();
-            if (Rulesets.Count > 0 && string.IsNullOrWhiteSpace(CampaignState.Model.RulesetId))
-            {
-                CampaignState.Model.RulesetId = Rulesets[0].Id;
-            }
         }
         catch (ApiRequestException ex)
         {

RpgRoller/Components/Pages/Home.Models.cs

@@ -14,6 +14,13 @@ public sealed class FormState<TModel>
     }
 }
 
+public sealed class FormSubmissionResult
+{
+    public Dictionary<string, string> Errors { get; init; } = [];
+    public string? ErrorMessage { get; init; }
+    public bool IsSuccess => Errors.Count == 0 && string.IsNullOrWhiteSpace(ErrorMessage);
+}
+
 public sealed class RegisterFormModel
 {
     public string Username { get; set; } = string.Empty;

RpgRoller/Components/Pages/Home.Presentation.cs

@@ -155,6 +155,14 @@ public partial class Home
         ShowEditCharacterModal = false;
         ShowCreateSkillModal = false;
         ShowEditSkillModal = false;
+        CreateCharacterInitialModel = new();
+        EditCharacterInitialModel = new();
+        CreateSkillInitialModel = new();
+        EditSkillInitialModel = new();
+        CreateCharacterFormVersion = 0;
+        EditCharacterFormVersion = 0;
+        CreateSkillFormVersion = 0;
+        EditSkillFormVersion = 0;
     }
 
     private void SetStatus(string message, bool isError)

RpgRoller/Components/Pages/Home.Skill.cs

@@ -6,13 +6,14 @@ public partial class Home
 {
     private void OpenCreateSkillModal()
     {
-        var model = CreateSkillState.Model;
+        CreateSkillInitialModel = new SkillFormModel
-        model.Name = string.Empty;
+        {
-        model.DiceRollDefinition = string.Empty;
+            Name = string.Empty,
-        model.WildDice = IsSelectedCampaignD6 ? 1 : 0;
+            DiceRollDefinition = string.Empty,
-        model.AllowFumble = IsSelectedCampaignD6;
+            WildDice = IsSelectedCampaignD6 ? 1 : 0,
-
+            AllowFumble = IsSelectedCampaignD6
-        CreateSkillState.ResetValidation();
+        };
+        CreateSkillFormVersion++;
         ShowCreateSkillModal = true;
     }
 
@@ -25,13 +26,14 @@ public partial class Home
 
         EditingSkillId = SelectedSkill.Id;
 
-        var model = EditSkillState.Model;
+        EditSkillInitialModel = new SkillFormModel
-        model.Name = SelectedSkill.Name;
+        {
-        model.DiceRollDefinition = SelectedSkill.DiceRollDefinition;
+            Name = SelectedSkill.Name,
-        model.WildDice = SelectedSkill.WildDice;
+            DiceRollDefinition = SelectedSkill.DiceRollDefinition,
-        model.AllowFumble = SelectedSkill.AllowFumble;
+            WildDice = SelectedSkill.WildDice,
-
+            AllowFumble = SelectedSkill.AllowFumble
-        EditSkillState.ResetValidation();
+        };
+        EditSkillFormVersion++;
         ShowEditSkillModal = true;
     }
 
@@ -42,29 +44,29 @@ public partial class Home
         EditingSkillId = null;
     }
 
-    private async Task CreateSkillAsync()
+    private async Task<FormSubmissionResult> CreateSkillAsync(SkillFormModel model)
     {
-        CreateSkillState.ResetValidation();
-
         if (SelectedCharacter is null)
         {
-            CreateSkillState.ErrorMessage = "Select a character first.";
+            return new FormSubmissionResult { ErrorMessage = "Select a character first." };
-            return;
         }
 
-        var model = CreateSkillState.Model;
+        var validationErrors = new Dictionary<string, string>();
-        AddRequiredError(CreateSkillState.Errors, "name", model.Name, "Skill name is required.");
+        AddRequiredError(validationErrors, "name", model.Name, "Skill name is required.");
-        AddRequiredError(CreateSkillState.Errors, "diceRollDefinition", model.DiceRollDefinition, "Expression is required.");
+        AddRequiredError(validationErrors, "diceRollDefinition", model.DiceRollDefinition, "Expression is required.");
 
         if (IsSelectedCampaignD6 && model.WildDice < 1)
         {
-            CreateSkillState.Errors["wildDice"] = "D6 skills require at least one wild die.";
+            validationErrors["wildDice"] = "D6 skills require at least one wild die.";
         }
 
-        if (CreateSkillState.Errors.Count > 0)
+        if (validationErrors.Count > 0)
         {
-            CreateSkillState.ErrorMessage = "Resolve validation issues before submitting.";
+            return new FormSubmissionResult
-            return;
+            {
+                ErrorMessage = "Resolve validation issues before submitting.",
+                Errors = validationErrors
+            };
         }
 
         IsMutating = true;
@@ -78,10 +80,11 @@ public partial class Home
             CloseSkillModals();
             await RefreshCampaignScopeAsync();
             SetStatus("Skill created.", false);
+            return new FormSubmissionResult();
         }
         catch (ApiRequestException ex)
         {
-            CreateSkillState.ErrorMessage = ex.Message;
+            return new FormSubmissionResult { ErrorMessage = ex.Message };
         }
         finally
         {
@@ -89,29 +92,29 @@ public partial class Home
         }
     }
 
-    private async Task UpdateSkillAsync()
+    private async Task<FormSubmissionResult> UpdateSkillAsync(SkillFormModel model)
     {
-        EditSkillState.ResetValidation();
-
         if (!EditingSkillId.HasValue)
         {
-            EditSkillState.ErrorMessage = "No skill selected.";
+            return new FormSubmissionResult { ErrorMessage = "No skill selected." };
-            return;
         }
 
-        var model = EditSkillState.Model;
+        var validationErrors = new Dictionary<string, string>();
-        AddRequiredError(EditSkillState.Errors, "name", model.Name, "Skill name is required.");
+        AddRequiredError(validationErrors, "name", model.Name, "Skill name is required.");
-        AddRequiredError(EditSkillState.Errors, "diceRollDefinition", model.DiceRollDefinition, "Expression is required.");
+        AddRequiredError(validationErrors, "diceRollDefinition", model.DiceRollDefinition, "Expression is required.");
 
         if (IsSelectedCampaignD6 && model.WildDice < 1)
         {
-            EditSkillState.Errors["wildDice"] = "D6 skills require at least one wild die.";
+            validationErrors["wildDice"] = "D6 skills require at least one wild die.";
         }
 
-        if (EditSkillState.Errors.Count > 0)
+        if (validationErrors.Count > 0)
         {
-            EditSkillState.ErrorMessage = "Resolve validation issues before submitting.";
+            return new FormSubmissionResult
-            return;
+            {
+                ErrorMessage = "Resolve validation issues before submitting.",
+                Errors = validationErrors
+            };
         }
 
         IsMutating = true;
@@ -126,10 +129,11 @@ public partial class Home
             CloseSkillModals();
             await RefreshCampaignScopeAsync();
             SetStatus("Skill updated.", false);
+            return new FormSubmissionResult();
         }
         catch (ApiRequestException ex)
         {
-            EditSkillState.ErrorMessage = ex.Message;
+            return new FormSubmissionResult { ErrorMessage = ex.Message };
         }
         finally
         {

RpgRoller/Components/Pages/Home.State.cs

@@ -17,14 +17,6 @@ public partial class Home
     private const string MobilePanelSessionKey = "play-panel";
     private static readonly JsonSerializerOptions JsonOptions = new(JsonSerializerDefaults.Web);
 
-    private FormState<RegisterFormModel> RegisterState { get; } = new();
-    private FormState<LoginFormModel> LoginState { get; } = new();
-    private FormState<CampaignFormModel> CampaignState { get; } = new();
-    private FormState<CharacterFormModel> CreateCharacterState { get; } = new();
-    private FormState<CharacterFormModel> EditCharacterState { get; } = new();
-    private FormState<SkillFormModel> CreateSkillState { get; } = new();
-    private FormState<SkillFormModel> EditSkillState { get; } = new();
-
     private UserSummary? User { get; set; }
     private Guid? ActiveCharacterId { get; set; }
     private Guid? SelectedCampaignId { get; set; }
@@ -55,6 +47,14 @@ public partial class Home
     private bool ShowEditSkillModal { get; set; }
     private Guid? EditingCharacterId { get; set; }
     private Guid? EditingSkillId { get; set; }
+    private CharacterFormModel CreateCharacterInitialModel { get; set; } = new();
+    private CharacterFormModel EditCharacterInitialModel { get; set; } = new();
+    private SkillFormModel CreateSkillInitialModel { get; set; } = new();
+    private SkillFormModel EditSkillInitialModel { get; set; } = new();
+    private int CreateCharacterFormVersion { get; set; }
+    private int EditCharacterFormVersion { get; set; }
+    private int CreateSkillFormVersion { get; set; }
+    private int EditSkillFormVersion { get; set; }
     private bool StateRefreshInProgress { get; set; }
     private bool HasInteractiveRenderStarted { get; set; }
     private DotNetObjectReference<Home>? DotNetRef { get; set; }

RpgRoller/Components/Pages/Home.razor

@@ -27,8 +27,6 @@
 
         case HomeViewMode.Anonymous:
             <AuthSection
-                RegisterState="RegisterState"
-                LoginState="LoginState"
                 IsMutating="IsMutating"
                 StatusMessage="StatusMessage"
                 StatusIsError="StatusIsError"
@@ -116,7 +114,6 @@
                         SelectedCampaignId="SelectedCampaignId"
                         SelectedCampaignName="SelectedCampaignName"
                         SelectedCampaign="SelectedCampaign"
-                        CampaignState="CampaignState"
                         Rulesets="Rulesets"
                         IsMutating="IsMutating"
                         OwnerLabel="OwnerLabel"
@@ -137,7 +134,8 @@
     SubmitLabel="Create Character"
     NameInputId="character-create-name"
     CampaignInputId="character-create-campaign"
-    FormState="CreateCharacterState"
+    InitialModel="CreateCharacterInitialModel"
+    FormVersion="CreateCharacterFormVersion"
     Campaigns="Campaigns"
     IsMutating="IsMutating"
     SubmitRequested="CreateCharacterAsync"
@@ -149,7 +147,8 @@
     SubmitLabel="Save Character"
     NameInputId="character-edit-name"
     CampaignInputId="character-edit-campaign"
-    FormState="EditCharacterState"
+    InitialModel="EditCharacterInitialModel"
+    FormVersion="EditCharacterFormVersion"
     Campaigns="Campaigns"
     IsMutating="IsMutating"
     SubmitRequested="UpdateCharacterAsync"
@@ -164,7 +163,8 @@
     ExpressionInputId="skill-create-expression"
     WildDiceInputId="skill-create-wild-dice"
     AllowFumbleInputId="skill-create-allow-fumble"
-    FormState="CreateSkillState"
+    InitialModel="CreateSkillInitialModel"
+    FormVersion="CreateSkillFormVersion"
     IsMutating="IsMutating"
     SubmitRequested="CreateSkillAsync"
     CancelRequested="CloseSkillModals" />
@@ -178,7 +178,8 @@
     ExpressionInputId="skill-edit-expression"
     WildDiceInputId="skill-edit-wild-dice"
     AllowFumbleInputId="skill-edit-allow-fumble"
-    FormState="EditSkillState"
+    InitialModel="EditSkillInitialModel"
+    FormVersion="EditSkillFormVersion"
     IsMutating="IsMutating"
     SubmitRequested="UpdateSkillAsync"
     CancelRequested="CloseSkillModals" />

RpgRoller/Components/Pages/HomeControls/AuthSection.razor

@@ -65,11 +65,8 @@
 </main>
 
 @code {
-    [Parameter]
+    private FormState<RegisterFormModel> RegisterState { get; } = new();
-    public FormState<RegisterFormModel> RegisterState { get; set; } = new();
+    private FormState<LoginFormModel> LoginState { get; } = new();
-
-    [Parameter]
-    public FormState<LoginFormModel> LoginState { get; set; } = new();
 
     [Parameter]
     public bool IsMutating { get; set; }
@@ -81,18 +78,55 @@
     public bool StatusIsError { get; set; }
 
     [Parameter]
-    public EventCallback RegisterSubmitted { get; set; }
+    public Func<RegisterFormModel, Task<FormSubmissionResult>> RegisterSubmitted { get; set; } = _ => Task.FromResult(new FormSubmissionResult());
 
     [Parameter]
-    public EventCallback LoginSubmitted { get; set; }
+    public Func<LoginFormModel, Task<FormSubmissionResult>> LoginSubmitted { get; set; } = _ => Task.FromResult(new FormSubmissionResult());
 
     private async Task SubmitRegisterAsync()
     {
-        await RegisterSubmitted.InvokeAsync();
+        RegisterState.ResetValidation();
+
+        var result = await RegisterSubmitted.Invoke(new RegisterFormModel
+        {
+            Username = RegisterState.Model.Username,
+            DisplayName = RegisterState.Model.DisplayName,
+            Password = RegisterState.Model.Password
+        });
+
+        ApplyResult(RegisterState, result);
+        if (result.IsSuccess)
+        {
+            RegisterState.Model.Password = string.Empty;
+        }
     }
 
     private async Task SubmitLoginAsync()
     {
-        await LoginSubmitted.InvokeAsync();
+        LoginState.ResetValidation();
+
+        var result = await LoginSubmitted.Invoke(new LoginFormModel
+        {
+            Username = LoginState.Model.Username,
+            Password = LoginState.Model.Password
+        });
+
+        ApplyResult(LoginState, result);
+        if (result.IsSuccess)
+        {
+            LoginState.Model.Password = string.Empty;
+        }
+    }
+
+    private static void ApplyResult<TModel>(FormState<TModel> state, FormSubmissionResult result)
+        where TModel : new()
+    {
+        state.Errors.Clear();
+        foreach (var (key, value) in result.Errors)
+        {
+            state.Errors[key] = value;
+        }
+
+        state.ErrorMessage = result.ErrorMessage;
     }
 }

RpgRoller/Components/Pages/HomeControls/CampaignManagementPanel.razor

@@ -29,7 +29,7 @@
         {
             <p class="form-error">@CampaignState.ErrorMessage</p>
         }
-        <form class="form-grid" @onsubmit="CreateCampaignSubmitted" @onsubmit:preventDefault>
+        <form class="form-grid" @onsubmit="SubmitCreateCampaignAsync" @onsubmit:preventDefault>
             <label for="campaign-name">Campaign name</label>
             <input id="campaign-name" @bind="CampaignState.Model.Name" @bind:event="oninput" />
             @if (CampaignState.Errors.TryGetValue("name", out var campaignNameError))
@@ -98,6 +98,8 @@
 </main>
 
 @code {
+    private FormState<CampaignFormModel> CampaignState { get; } = new();
+
     [Parameter]
     public IReadOnlyList<CampaignSummary> Campaigns { get; set; } = [];
 
@@ -110,9 +112,6 @@
     [Parameter]
     public CampaignDetails? SelectedCampaign { get; set; }
 
-    [Parameter]
-    public FormState<CampaignFormModel> CampaignState { get; set; } = new();
-
     [Parameter]
     public IReadOnlyList<RulesetDefinition> Rulesets { get; set; } = [];
 
@@ -129,11 +128,42 @@
     public EventCallback<ChangeEventArgs> CampaignSelectionChanged { get; set; }
 
     [Parameter]
-    public EventCallback CreateCampaignSubmitted { get; set; }
+    public Func<CampaignFormModel, Task<FormSubmissionResult>> CreateCampaignSubmitted { get; set; } = _ => Task.FromResult(new FormSubmissionResult());
 
     [Parameter]
     public EventCallback CreateCharacterRequested { get; set; }
 
     [Parameter]
     public EventCallback<CharacterSummary> EditCharacterRequested { get; set; }
+
+    protected override void OnParametersSet()
+    {
+        if (string.IsNullOrWhiteSpace(CampaignState.Model.RulesetId) && Rulesets.Count > 0)
+        {
+            CampaignState.Model.RulesetId = Rulesets[0].Id;
+        }
+    }
+
+    private async Task SubmitCreateCampaignAsync()
+    {
+        CampaignState.ResetValidation();
+
+        var result = await CreateCampaignSubmitted.Invoke(new CampaignFormModel
+        {
+            Name = CampaignState.Model.Name,
+            RulesetId = CampaignState.Model.RulesetId
+        });
+
+        CampaignState.Errors.Clear();
+        foreach (var (key, value) in result.Errors)
+        {
+            CampaignState.Errors[key] = value;
+        }
+
+        CampaignState.ErrorMessage = result.ErrorMessage;
+        if (result.IsSuccess)
+        {
+            CampaignState.Model.Name = string.Empty;
+        }
+    }
 }

RpgRoller/Components/Pages/HomeControls/CharacterFormModal.razor

@@ -41,6 +41,9 @@
 }
 
 @code {
+    private FormState<CharacterFormModel> FormState { get; } = new();
+    private int AppliedFormVersion { get; set; } = -1;
+
     [Parameter]
     public bool Visible { get; set; }
 
@@ -57,7 +60,10 @@
     public string CampaignInputId { get; set; } = "character-campaign";
 
     [Parameter]
-    public FormState<CharacterFormModel> FormState { get; set; } = new();
+    public CharacterFormModel InitialModel { get; set; } = new();
+
+    [Parameter]
+    public int FormVersion { get; set; }
 
     [Parameter]
     public IReadOnlyList<CampaignSummary> Campaigns { get; set; } = [];
@@ -66,13 +72,39 @@
     public bool IsMutating { get; set; }
 
     [Parameter]
-    public EventCallback SubmitRequested { get; set; }
+    public Func<CharacterFormModel, Task<FormSubmissionResult>> SubmitRequested { get; set; } = _ => Task.FromResult(new FormSubmissionResult());
 
     [Parameter]
     public EventCallback CancelRequested { get; set; }
 
+    protected override void OnParametersSet()
+    {
+        if (!Visible || FormVersion == AppliedFormVersion)
+        {
+            return;
+        }
+
+        FormState.Model.Name = InitialModel.Name;
+        FormState.Model.CampaignId = InitialModel.CampaignId;
+        FormState.ResetValidation();
+        AppliedFormVersion = FormVersion;
+    }
+
     private async Task SubmitAsync()
     {
-        await SubmitRequested.InvokeAsync();
+        FormState.ResetValidation();
+
+        var result = await SubmitRequested.Invoke(new CharacterFormModel
+        {
+            Name = FormState.Model.Name,
+            CampaignId = FormState.Model.CampaignId
+        });
+
+        foreach (var (key, value) in result.Errors)
+        {
+            FormState.Errors[key] = value;
+        }
+
+        FormState.ErrorMessage = result.ErrorMessage;
     }
 }

RpgRoller/Components/Pages/HomeControls/SkillFormModal.razor

@@ -45,6 +45,9 @@
 }
 
 @code {
+    private FormState<SkillFormModel> FormState { get; } = new();
+    private int AppliedFormVersion { get; set; } = -1;
+
     [Parameter]
     public bool Visible { get; set; }
 
@@ -70,19 +73,52 @@
     public string AllowFumbleInputId { get; set; } = "skill-fumble";
 
     [Parameter]
-    public FormState<SkillFormModel> FormState { get; set; } = new();
+    public SkillFormModel InitialModel { get; set; } = new();
+
+    [Parameter]
+    public int FormVersion { get; set; }
 
     [Parameter]
     public bool IsMutating { get; set; }
 
     [Parameter]
-    public EventCallback SubmitRequested { get; set; }
+    public Func<SkillFormModel, Task<FormSubmissionResult>> SubmitRequested { get; set; } = _ => Task.FromResult(new FormSubmissionResult());
 
     [Parameter]
     public EventCallback CancelRequested { get; set; }
 
+    protected override void OnParametersSet()
+    {
+        if (!Visible || FormVersion == AppliedFormVersion)
+        {
+            return;
+        }
+
+        FormState.Model.Name = InitialModel.Name;
+        FormState.Model.DiceRollDefinition = InitialModel.DiceRollDefinition;
+        FormState.Model.WildDice = InitialModel.WildDice;
+        FormState.Model.AllowFumble = InitialModel.AllowFumble;
+        FormState.ResetValidation();
+        AppliedFormVersion = FormVersion;
+    }
+
     private async Task SubmitAsync()
     {
-        await SubmitRequested.InvokeAsync();
+        FormState.ResetValidation();
+
+        var result = await SubmitRequested.Invoke(new SkillFormModel
+        {
+            Name = FormState.Model.Name,
+            DiceRollDefinition = FormState.Model.DiceRollDefinition,
+            WildDice = FormState.Model.WildDice,
+            AllowFumble = FormState.Model.AllowFumble
+        });
+
+        foreach (var (key, value) in result.Errors)
+        {
+            FormState.Errors[key] = value;
+        }
+
+        FormState.ErrorMessage = result.ErrorMessage;
     }
 }

TECH.md

@@ -93,7 +93,8 @@ This pattern is a strong baseline for low to medium scale and should be the defa
 
 - Blazor component tree rooted in `Components/App.razor` and `Components/Pages/Home.razor`.
 - Home page logic split by concern with partials (`Home.State/Auth/Campaign/Character/Skill/Lifecycle/Realtime/Api/Presentation/Validation.cs`) to keep churn localized.
-- Form UX state uses reusable `FormState<TModel>` containers (`Home.Models.cs`) rather than parallel form/error/message property sets.
+- Form UX state uses reusable `FormState<TModel>` containers in leaf controls (`HomeControls/*`) rather than parallel form/error/message property sets in `Home`.
+- `Home` workflows return `FormSubmissionResult` so controls can render field and summary errors without parent-owned form wiring.
 - Browser API calls and SSE are handled via `wwwroot/js/rpgroller-api.js` interop.
 - UI state is maintained server-side per circuit with session/tab persistence for campaign + screen selection.
 - SSE-driven campaign refresh with reconnect backoff and explicit offline/manual-refresh fallback.