Reworked message system, implemented in ManageUsers and EmailSignup

Wave/Components/AlertComponent.razor

@@ -0,0 +1,45 @@
+@using Wave.Utilities
+@implements IDisposable
+@inject IMessageDisplay Messages
+
+@if (Message is {} message) {
+	<div class="alert @message.Type" role="alert">
+		<div> </div>
+		<div>
+			@if (message.Title is null) {
+				@message.Body
+			} else {
+				<span class="font-bold">@message.Title</span>
+				<span><small>@message.Body</small></span>
+			}
+		</div>
+		@if (CanDelete) {
+			<button class="btn btn-sm btn-square btn-ghost" onclick="this.parentElement.remove();">
+				<svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor" class="w-6 h-6">
+					<path stroke-linecap="round" stroke-linejoin="round" d="M6 18 18 6M6 6l12 12"/>
+				</svg>
+			</button>
+		}
+	</div>
+}
+
+@code {
+	[Parameter]
+	public bool CanDelete { get; set; }
+	
+	private IMessageDisplay.Message? Message { get; set; }
+
+	protected override void OnInitialized() {
+		Messages.OnMessage += OnMessage;
+	}
+
+	private bool OnMessage(IMessageDisplay.Message message) {
+		Message = message;
+		StateHasChanged();
+		return true;
+	}
+
+	public void Dispose() {
+		Messages.OnMessage -= OnMessage;
+	}
+}

Wave/Components/Layout/MainLayout.razor

@@ -28,7 +28,14 @@
 				<SectionOutlet SectionName="GlobalHeader" />
 				<input id="narrow-reading-toggle" type="checkbox" class="narrow-reading-toggle" />
 				<div class="flex-1 container mx-auto px-4 md:px-12 py-8 reading-toggle-target h-full">
+					<AlertComponent CanDelete="true" />
 					@Body
+					@if (HttpContext is null || HttpContext?.GetEndpoint()?
+						     .Metadata.GetMetadata<RenderModeAttribute>()?
+					     .Mode is not null) { 
+						// for some reason that's how you test for interactive render modes
+						<ToastComponent />
+					}
 				</div>
 			</main>
 			<footer class="flex flex-col md:flex-row items-center justify-center p-4 gap-y-3 gap-x-4 bg-base-300 text-base-content">
@@ -87,4 +94,6 @@
 @code {
 	[CascadingParameter(Name = "UserTheme")]
 	private string? UserTheme { get; set; }
+	[CascadingParameter]
+	private HttpContext? HttpContext { get; set; }
 }

Wave/Components/Pages/EmailSignup.razor

@@ -7,6 +7,7 @@
 @using System.Net
 @using Microsoft.EntityFrameworkCore
 @using Wave.Services
+@using Wave.Utilities	
 
 @inject ILogger<EmailSignup> Logger
 @inject IStringLocalizer<EmailSignup> Localizer
@@ -16,15 +17,10 @@
 @inject NavigationManager Navigation
 @inject IAdvancedEmailSender EmailSender
 @inject EmailTemplateService TemplateService
+@inject IMessageDisplay Messages
 
 <PageTitle>@(TitlePrefix + Localizer["Title"])</PageTitle>
 
-@if (!string.IsNullOrWhiteSpace(Message)) {
-	<div class="alert alert-success">
-		<span>@Message</span>
-	</div>
-}
-
 <BoardComponent CenterContent="true">
 	<BoardCardComponent Heading="@Localizer["Title"]">
 		<EditForm method="post" FormName="email-signup" Model="Model" OnValidSubmit="OnValidSubmit">
@@ -55,8 +51,6 @@
 	[Parameter, SupplyParameterFromQuery(Name = "token")]
     public string? Token { get; set; }
 
-	private string Message { get; set; } = string.Empty;
-
 	protected override async Task OnInitializedAsync() {
 		if (Features.Value.EmailSubscriptions is not true)
 			throw new ApplicationException("Email subscriptions not enabled.");
@@ -66,19 +60,19 @@
 			var id = await TemplateService.ValidateTokensAsync(Id, Token, deleteToken: false);
 
 			if (id is null) {
-				Message = Localizer["Failure_Message"];
+				Messages.ShowError(Localizer["Failure_Message"]);
 				return;
 			}
 
 			await using var context = await ContextFactory.CreateDbContextAsync();
 			var subscriber = context.Set<EmailSubscriber>().IgnoreQueryFilters().FirstOrDefault(s => s.Id == id);
 			if (subscriber is null) {
-				Message = Localizer["Failure_Message"];
+				Messages.ShowError(Localizer["Failure_Message"]);
 				return;
 			}
 			subscriber.Unsubscribed = false;
 			await context.SaveChangesAsync();
-			Message = Localizer["Success_Message"];
+			Messages.ShowSuccess(Localizer["Success_Message"]);
 
 			await TemplateService.ValidateTokensAsync(Id, Token, deleteToken: true);
 			
@@ -92,7 +86,7 @@
 				Localizer["WelcomeEmailSubject"], Localizer["WelcomeEmailTitle"], Localizer["WelcomeEmailBody"], articles);
 		} catch (Exception ex) {
 			Logger.LogError(ex, "Error trying to confirm subscriber.");
-			Message = Localizer["Failure_Message"];
+			Messages.ShowError(Localizer["Failure_Message"]);
 		}
 	}
 
@@ -101,7 +95,7 @@
 			throw new ApplicationException("Email subscriptions not enabled.");
 
 		try {
-			Message = Localizer["Submit_Message"];
+			Messages.ShowSuccess(Localizer["Submit_Message"]);
 			await using var context = await ContextFactory.CreateDbContextAsync();
 
 			var subscriber = context.Set<EmailSubscriber>().IgnoreQueryFilters().FirstOrDefault(s => s.Email == Model.Email);
@@ -127,7 +121,6 @@
 			}
 		} catch (Exception ex) {
 			Logger.LogError(ex, "Failed to create subscriber/send confirmation mail.");
-			Message = Localizer["Failure_Message"];
 		}
 	}
 

Wave/Components/Pages/ManageUsers.razor

@@ -11,6 +11,7 @@
 @inject RoleManager<IdentityRole> RoleManager
 @inject UserManager<ApplicationUser> UserManager
 @inject IStringLocalizer<ManageUsers> Localizer
+@inject IMessageDisplay Toast
 
 <PageTitle>@(TitlePrefix + Localizer["Title"])</PageTitle>
 
@@ -55,12 +56,9 @@
     }
 </section>
 
-<ToastComponent @ref="Toast" />
-
 @code {
 	[CascadingParameter(Name = "TitlePrefix")]
 	private string TitlePrefix { get; set; } = default!;
-	public IMessageDisplay Toast { get; set; } = null!;
     private string ModalId { get; } = "UserDialog";
 
 	[CascadingParameter]

Wave/Components/ToastComponent.razor

@@ -1,9 +1,11 @@
 @using Wave.Utilities
-@implements IMessageDisplay
+@implements IDisposable
+@inject IMessageDisplay Messages
+@rendermode InteractiveServer
 
 <div class="toast toast-start z-10" role="alert">
-	@foreach (var message in Messages) {
-		<div class="alert @message.Type" @onclick="() => Messages.Remove(message)">
+	@foreach (var message in MessagesDisplayed) {
+		<div class="alert @message.Type" @onclick="() => MessagesDisplayed.Remove(message)">
 			@if (message.Title is null) {
 				@message.Body
 			} else {
@@ -15,10 +17,19 @@
 </div>
 
 @code {
-	private List<IMessageDisplay.Message> Messages { get; } = [];
+	private List<IMessageDisplay.Message> MessagesDisplayed { get; } = [];
 
-	public void ShowMessage(IMessageDisplay.Message message) {
-		Messages.Add(message);
+	protected override void OnInitialized() {
+		Messages.OnMessage += OnMessage;
+	}
+
+	private bool OnMessage(IMessageDisplay.Message message) {
+		MessagesDisplayed.Add(message);
 		StateHasChanged();
+		return true;
+	}
+
+	public void Dispose() {
+		Messages.OnMessage -= OnMessage;
 	}
 }

Wave/Program.cs

@@ -129,6 +129,7 @@
 	logMessages.Add("No Email provider configured.");
 }
 
+builder.Services.AddSingleton<IMessageDisplay, MessageService>();
 builder.Services.AddSingleton<FileSystemService>();
 builder.Services.AddSingleton<EmailTemplateService>();
 builder.Services.AddHostedService<EmailBackgroundWorker>();

Wave/Services/MessageService.cs

@@ -0,0 +1,19 @@
+using Wave.Utilities;
+using static Wave.Utilities.IMessageDisplay;
+
+namespace Wave.Services;
+
+public class MessageService : IMessageDisplay {
+	private Queue<Message> Messages { get; } = new();
+
+	public event Func<Message, bool>? OnMessage;
+
+	public IReadOnlyList<Message> GetMessages() => [.. Messages];
+	public Message? Pop() => Messages.TryDequeue(out var m) ? m : null;
+
+	public void ShowMessage(Message message) {
+		if (OnMessage?.Invoke(message) is not true) {
+			Messages.Enqueue(message);
+		}
+	}
+}

Wave/Utilities/IMessageDisplay.cs

@@ -1,16 +1,21 @@
 namespace Wave.Utilities;
 
 public interface IMessageDisplay {
-	public void ShowMessage(Message message);
+	IReadOnlyList<Message> GetMessages();
+	event Func<Message, bool>? OnMessage;
 
-	public void ShowInfo(string message, string? title = null)
+	Message? Pop();
+
+	void ShowMessage(Message message);
+	
+	void ShowInfo(string message, string? title = null)
 		=> ShowMessage(new Message(message, "alert-info", title, DateTimeOffset.UtcNow));
-	public void ShowSuccess(string message, string? title = null)
+	void ShowSuccess(string message, string? title = null)
 		=> ShowMessage(new Message(message, "alert-success", title, DateTimeOffset.UtcNow));
-	public void ShowWarning(string message, string? title = null)
+	void ShowWarning(string message, string? title = null)
 		=> ShowMessage(new Message(message, "alert-warning", title, DateTimeOffset.UtcNow));
-	public void ShowError(string message, string? title = null)
+	void ShowError(string message, string? title = null)
 		=> ShowMessage(new Message(message, "alert-error", title, DateTimeOffset.UtcNow));
 
-	public sealed record Message(string Body, string Type, string? Title, DateTimeOffset Created);
+	sealed record Message(string Body, string Type, string? Title, DateTimeOffset Created);
 }