R2 accounts in decePub: forgotten password, email by code, sessions, the theme kept with the login

Completion program R2, with PrivaPub's routes of the same release.

- Pages/PasswordRecovery.razor (/password-recovery): asks for a login or an address and shows the server's one
  sentence; with ?rc= it takes the code out of the address bar at once, checks it and sets a new password. Login links
  there ("Forgot your password?").
- Settings, the login: its email address with a verified badge, changed with the password and the code emailed to it
  (DOtp), removed with the password; "Sign out everywhere" (every device and persona, asked first).
- A password change takes the new JWT PrivaPub answers and exchanges the persona's token again, since every persona
  token ended with it.
- The theme kept with the login (PageSettings.SyncWithLogin, Settings > General): taken at sign-in and start-up once a
  client saved it, saved 1.5 s after a change here, never posted back when nothing changed, never the language.
- Login, Setup and Join start the session through CascadingState.SignedIn, which takes the login's theme.
- 38 keys in both resx files; CLAUDE.md follows.

Verified: dotnet build decePubClient.csproj -c Release (0 errors, no new warnings).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WpVCoDeM1qUTRp4fXQdfof

Pages/Join.razor

@@ -115,7 +115,7 @@
 			return;
 		}
 
-		await CascadingState.LoadSession();
+		await CascadingState.SignedIn(result.Data as JwtUser);
 		isWorking = false;
 		Toast.AddResponseSuccess(Localizer["Welcome: your persona is in the group."]);
 		Navigation.NavigateTo("");

Pages/Login.razor

@@ -4,7 +4,8 @@
 
 @* One sign-in for both of PrivaPub's APIs: the root signs in here, then picks the persona to act as when it has more than
    one (CascadingState.LoadSession picks the last one used, or the only one). A server without an administrator offers
-   its setup (Setup); anyone else joins through a group's invitation (Join). *@
+   its setup (Setup); anyone else joins through a group's invitation (Join). A forgotten password is recovered through
+   the login's verified address (PasswordRecovery). *@
 <section class="block relative w-full h-full neo-inset neo-xs rounded-xl">
 
 	<div class="flex flex-col items-center gap-6 p-4 md:p-5 w-full h-full absolute overflow-y-auto">
@@ -49,6 +50,7 @@
 						}
 						<span>@Localizer["Login"]</span>
 					</DButton>
+					<a class="link text-sm self-center touch-target" href="password-recovery" data-recovery-offer>@Localizer["Forgot your password?"]</a>
 				</EditForm>
 				<p class="text-sm text-center">
 					@Localizer["Have an invitation?"] <a class="link touch-target" href="join" data-join-offer>@Localizer["Join with an invitation"]</a>
@@ -130,7 +132,7 @@
 			return;
 		}
 
-		await CascadingState.LoadSession();
+		await CascadingState.SignedIn(result.Data as JwtUser);
 		isWorking = false;
 		if (CascadingState.Personas.Count == 1 && CascadingState.Persona is not null)
 			Continue();

Pages/PasswordRecovery.razor

@@ -0,0 +1,216 @@
+@page "/password-recovery"
+@inherits LocalizableComponentBase
+<Title>@Localizer["Forgot your password?"]</Title>
+
+@* A forgotten password (PrivaPub's /clientapi/user/recover): the login's name, or its verified address, asks for a link,
+   and PrivaPub answers everyone with the same sentence, so the page never tells whether a login or an address exists.
+   The link comes back here with its code (?rc=), which leaves the address bar and the history at once and stays in the
+   page; a new password set with it ends every session the login had, and the reader signs in with it. *@
+<section class="block relative w-full h-full neo-inset neo-xs rounded-xl">
+
+	<div class="flex flex-col items-center gap-6 p-4 md:p-5 w-full h-full absolute overflow-y-auto">
+
+		@if (CascadingState.IsSignedIn)
+		{
+			<div class="flex flex-col gap-3 w-full max-w-sm mt-6 md:mt-16 p-5 rounded-xl neo-raised neo-sm" data-recovery-signed-in>
+				<h1 class="text-xl font-bold">@Localizer["You are signed in"]</h1>
+				<DButton Href="" Color="DColor.Primary">@Localizer["Home"]</DButton>
+			</div>
+		}
+		else if (recoveryCode is null && sentence is not null)
+		{
+			<div class="flex flex-col gap-3 w-full max-w-sm mt-6 md:mt-16 p-5 rounded-xl neo-raised neo-sm" data-recovery-sent>
+				<h1 class="text-xl font-bold">@Localizer["Check your inbox"]</h1>
+				<p class="text-sm">@sentence</p>
+				<DButton Href="login" Color="DColor.Primary">@Localizer["Login"]</DButton>
+			</div>
+		}
+		else if (recoveryCode is null)
+		{
+			<EditForm Model="request" OnValidSubmit="Request" class="flex flex-col gap-4 w-full max-w-sm mt-6 md:mt-16 p-5 rounded-xl neo-raised neo-sm" data-recovery-request>
+				<DataAnnotationsValidator />
+				<h1 class="text-xl font-bold">@Localizer["Forgot your password?"]</h1>
+				<p class="text-sm opacity-70">@Localizer["Give your login's username or its email address: if the login has a verified address, a link to choose a new password is sent to it."]</p>
+
+				<label class="flex flex-col gap-1">
+					<span class="text-sm">@Localizer["Username"]</span>
+					<DInput TValue="string" class="w-full" Value="request.UserName" ValueChanged="v => request.UserName = NullIfBlank(v)" ValueExpression="() => request.UserName"
+							Immediate="true" disabled="@request.IsUsernameDisabled" autocomplete="username" autocapitalize="none" spellcheck="false" data-recovery-username>
+						<Prefix><i class="ion-md-person"></i></Prefix>
+					</DInput>
+				</label>
+				<span class="text-sm text-center opacity-70">@Localizer["or"]</span>
+				<label class="flex flex-col gap-1">
+					<span class="text-sm">@Localizer["Email address"]</span>
+					<DInput TValue="string" Type="email" class="w-full" Value="request.Email" ValueChanged="v => request.Email = NullIfBlank(v)" ValueExpression="() => request.Email"
+							Immediate="true" disabled="@request.IsEmailDisabled" autocomplete="email" inputmode="email" autocapitalize="none" spellcheck="false" data-recovery-email>
+						<Prefix><i class="ion-md-mail"></i></Prefix>
+					</DInput>
+				</label>
+
+				<ErrorViewer AdditionalError="@error" />
+
+				<DButton Type="submit" Color="DColor.Primary" Disabled="IsDefaultDisabled || isWorking" data-recovery-submit>
+					@if (isWorking)
+					{
+						<DLoading Size="DSize.Sm" LabelText="@Localizer["loading"]" />
+					}
+					<span>@Localizer["Send the recovery link"]</span>
+				</DButton>
+				<a class="link text-sm self-center touch-target" href="login">@Localizer["I remember it: sign in"]</a>
+			</EditForm>
+		}
+		else if (IsLoading)
+		{
+			<DLoading Variant="DLoadingVariant.Dots" LabelText="@Localizer["loading"]" />
+		}
+		else if (isCodeValid is false)
+		{
+			<div class="flex flex-col gap-3 w-full max-w-sm mt-6 md:mt-16 p-5 rounded-xl neo-raised neo-sm" data-recovery-invalid>
+				<h1 class="text-xl font-bold">@Localizer["This recovery link doesn't work"]</h1>
+				<p class="text-sm">@Localizer["A link works for one hour, and only once. Ask for a new one."]</p>
+				<DButton Color="DColor.Primary" OnClick="AskAgain" data-recovery-again>@Localizer["Ask for a new link"]</DButton>
+			</div>
+		}
+		else
+		{
+			@* also while the code couldn't be checked (offline, or the check failed): the answer to the new password says *@
+			<EditForm Model="newPassword" OnValidSubmit="Recover" class="flex flex-col gap-4 w-full max-w-sm mt-6 md:mt-16 p-5 rounded-xl neo-raised neo-sm" data-recovery-new>
+				<DataAnnotationsValidator />
+				<h1 class="text-xl font-bold">@Localizer["Choose a new password"]</h1>
+				<p class="text-sm opacity-70">@Localizer["Every device signed in to this login is signed out."]</p>
+
+				<label class="flex flex-col gap-1">
+					<span class="text-sm">@Localizer["New password"]</span>
+					<DInput TValue="string" Type="password" class="w-full" @bind-Value="newPassword.NewPassword" autocomplete="new-password" data-recovery-password>
+						<Prefix><i class="ion-md-key"></i></Prefix>
+					</DInput>
+				</label>
+				<label class="flex flex-col gap-1">
+					<span class="text-sm">@Localizer["Repeat the new password"]</span>
+					<DInput TValue="string" Type="password" class="w-full" @bind-Value="newPassword.RepeatedPassword" autocomplete="new-password" data-recovery-repeat>
+						<Prefix><i class="ion-md-key"></i></Prefix>
+					</DInput>
+				</label>
+
+				<ErrorViewer AdditionalError="@error" />
+
+				<DButton Type="submit" Color="DColor.Primary" Disabled="IsDefaultDisabled || isWorking" data-recovery-new-submit>
+					@if (isWorking)
+					{
+						<DLoading Size="DSize.Sm" LabelText="@Localizer["loading"]" />
+					}
+					<span>@Localizer["Change the password"]</span>
+				</DButton>
+			</EditForm>
+		}
+
+	</div>
+
+</section>
+
+@code {
+	[Inject] AuthService AuthService { get; set; }
+
+	readonly PasswordRecoveryForm request = new();
+	NewPasswordForm newPassword = new();
+	/// <summary>The code of the link the page was opened from, kept here once it left the address bar.</summary>
+	string recoveryCode;
+	/// <summary>Whether the code works: null until PrivaPub said.</summary>
+	bool? isCodeValid;
+	/// <summary>PrivaPub's answer to a request, the same for everyone.</summary>
+	string sentence;
+	string error;
+	bool isWorking;
+
+	[SupplyParameterFromQuery(Name = "rc")] public string LinkCode { get; set; }
+
+	protected override async Task OnInitializedAsync()
+	{
+		if (LinkCode is { Length: > 0 } code)
+		{
+			recoveryCode = code.Trim();
+			newPassword.RecoveryCode = recoveryCode;
+			// the code is as good as the password for an hour: out of the address bar and the history at once
+			Navigation.NavigateTo("password-recovery", replace: true);
+		}
+
+		if (CascadingState.IsOffline)
+		{
+			WhenOnline(LoadData);
+			StartOnlinePolling();
+			IsLoading = false;
+			return;
+		}
+
+		await LoadData();
+		IsLoading = false;
+	}
+
+	async Task LoadData()
+	{
+		if (recoveryCode is null)
+			return;
+
+		var result = await AuthService.CheckRecoveryCode(recoveryCode);
+		if (result.IsInvalid)
+		{
+			error = result.ErrorMessage;
+			return;
+		}
+
+		isCodeValid = result.Data is true;
+	}
+
+	static string NullIfBlank(string value) => string.IsNullOrWhiteSpace(value) ? null : value;
+
+	async Task Request()
+	{
+		error = default;
+		isWorking = true;
+		request.UserName = request.UserName?.Trim();
+		request.Email = request.Email?.Trim().ToLowerInvariant();
+		var result = await AuthService.RequestRecovery(request);
+		isWorking = false;
+		if (result.IsInvalid)
+		{
+			error = result.ErrorMessage;
+			return;
+		}
+
+		sentence = result.Data is string { Length: > 0 } said
+			? said
+			: Localizer["If that account has an email address, a recovery link is on its way. It works for one hour."];
+	}
+
+	void AskAgain()
+	{
+		recoveryCode = null;
+		isCodeValid = null;
+		newPassword = new();
+		error = default;
+	}
+
+	async Task Recover()
+	{
+		error = default;
+		isWorking = true;
+		var result = await AuthService.Recover(newPassword);
+		isWorking = false;
+		if (result.StatusCode is (int)System.Net.HttpStatusCode.NotFound)
+		{
+			// used or expired meanwhile
+			isCodeValid = false;
+			return;
+		}
+
+		if (result.IsInvalid)
+		{
+			error = result.ErrorMessage;
+			return;
+		}
+
+		Toast.AddResponseSuccess(Localizer["Password changed: sign in with the new one."]);
+		Navigation.NavigateTo("login");
+	}
+}

Pages/Settings.razor

@@ -21,6 +21,10 @@
 							 ValueChanged="v => Update(s => s.SetDarkMode(v))" ValueExpression="() => IsDark" />
 					<DToggle LabelText="@Localizer["Grey"]" Value="IsGray"
 							 ValueChanged="v => Update(s => s.SetGray(v, IsDark))" ValueExpression="() => IsGray" />
+					@* The theme is the login's: taken at sign-in, saved to it as it changes here (CascadingState.SaveSettingsSoon). *@
+					<DToggle LabelText="@Localizer["Keep the theme the same on every device signed in to this login"]" Value="CascadingState.PublicCacheData.PageSettings.SyncWithLogin"
+							 ValueChanged="v => Update(s => s.SyncWithLogin = v)" ValueExpression="() => CascadingState.PublicCacheData.PageSettings.SyncWithLogin"
+							 data-sync-with-login />
 					<DToggle LabelText="@Localizer["Remind me to describe pictures before publishing"]" Value="CascadingState.PublicCacheData.PageSettings.RemindAltText"
 							 ValueChanged="v => Update(s => s.RemindAltText = v)" ValueExpression="() => CascadingState.PublicCacheData.PageSettings.RemindAltText"
 							 data-remind-alt-text />

Pages/Setup.razor

@@ -129,7 +129,7 @@
 			return;
 		}
 
-		await CascadingState.LoadSession();
+		await CascadingState.SignedIn(result.Data as JwtUser);
 		isWorking = false;
 		Toast.AddResponseSuccess(Localizer["PrivaPub is set up: you are its administrator."]);
 		Navigation.NavigateTo("");