threading fixes

Hyperbar/Configuration/ConfigurationChanged.cs

@@ -0,0 +1,5 @@
+namespace Hyperbar;
+
+public record ConfigurationChanged<TConfiguration>(TConfiguration Configuration) : INotification 
+    where TConfiguration : 
+    class;

Hyperbar/Configuration/ConfigurationInitializer.cs

@@ -1,13 +1,7 @@
-using Microsoft.Extensions.Configuration;
-using Microsoft.Extensions.Options;
-using System.Threading;
+using Microsoft.Extensions.Options;
 
 namespace Hyperbar;
 
-public record ConfigurationChanged<TConfiguration>(TConfiguration Configuration) : INotification 
-    where TConfiguration : 
-    class;
-
 public class ConfigurationInitializer<TConfiguration>(DefaultConfiguration<TConfiguration> defaults,
     IConfigurationWriter<TConfiguration> writer,
     IOptionsMonitor<TConfiguration> options,
@@ -17,12 +11,16 @@ public class ConfigurationInitializer<TConfiguration>(DefaultConfiguration<TConf
 {
     public Task InitializeAsync()
     {
-        options.OnChange(args =>
+        options.OnChange(async args =>
         {
-            mediator.PublishAsync(new ConfigurationChanged<TConfiguration>(args));
+            await mediator.PublishAsync(new ConfigurationChanged<TConfiguration>(args));
         });
 
-        writer.Write(defaults.Configuration);
+        if (defaults.Configuration is not null)
+        {
+            writer.Write(defaults.Configuration);
+        }
+
         return Task.CompletedTask;
     }
 }

Hyperbar/Configuration/DefaultConfiguration.cs

@@ -1,6 +1,8 @@
 namespace Hyperbar;
 
-public class DefaultConfiguration<TConfiguration>(TConfiguration configuration)
+public class DefaultConfiguration<TConfiguration>(TConfiguration? configuration = null) 
+    where TConfiguration :
+    class
 {
-    public TConfiguration Configuration => configuration;
+    public TConfiguration? Configuration => configuration;
 }

Hyperbar/Extensions/IServiceCollectionExtensions.cs

@@ -21,7 +21,7 @@ public static class IServiceCollectionExtensions
             {
                 Type notificationType = arguments[0];
 
-                services.TryAdd(new ServiceDescriptor(typeof(THandler), typeof(THandler), ServiceLifetime.Singleton));
+                services.TryAdd(new ServiceDescriptor(typeof(THandler), typeof(THandler), lifetime));
                 services.Add(new ServiceDescriptor(typeof(INotificationHandler<>).MakeGenericType(notificationType),
                     provider => provider.GetRequiredService<THandler>(), lifetime));
             }
@@ -53,13 +53,24 @@ public static class IServiceCollectionExtensions
                 Type responseType = arguments[1];
 
                 services.AddTransient(typeof(THandler));
-                services.AddTransient(responseType, provider => ((dynamic)provider.GetRequiredService<THandler>()).Map());
+                services.AddTransient(responseType, provider =>
+                {
+                    return ((dynamic)provider.GetRequiredService<THandler>()).Handle();
+                });
             }
         }
 
         return services;
     }
 
+    public static IServiceCollection AddConfiguration<TConfiguration>(this IServiceCollection services,
+        IConfiguration configuration)
+        where TConfiguration :
+        class, new()
+    {
+        return services.AddConfiguration<TConfiguration>(configuration, typeof(TConfiguration).Name, "Settings.json", null);
+    }
+
     public static IServiceCollection AddConfiguration<TConfiguration>(this IServiceCollection services,
         IConfiguration configuration,
         TConfiguration? defaults = null)
@@ -107,10 +118,11 @@ public static class IServiceCollectionExtensions
 
         if (defaults is not null)
         {
-            services.AddTransient(provider => new DefaultConfiguration<TConfiguration>(defaults));
-            services.AddTransient<IInitializer, ConfigurationInitializer<TConfiguration>>();
         }
 
+        services.AddTransient(provider => new DefaultConfiguration<TConfiguration>(defaults));
+        services.AddTransient<IInitializer, ConfigurationInitializer<TConfiguration>>();
+
         services.AddTransient<IWritableConfiguration<TConfiguration>, WritableConfiguration<TConfiguration>>();
         return services;
     }

Hyperbar/Mediators/IMappingHandler.cs

@@ -2,5 +2,5 @@
 
 public interface IMappingHandler<TFrom, TTo> : IHandler 
 {
-    TTo Map();
+    TTo Handle();
 }

Hyperbar/Mediators/INotificationHandler.cs

@@ -1,6 +1,7 @@
 namespace Hyperbar;
 
-public interface INotificationHandler<in TNotification>
+public interface INotificationHandler<in TNotification> :
+    IHandler
     where TNotification :
     INotification
 {

Hyperbar/Mediators/Mediator.cs

@@ -6,9 +6,9 @@ namespace Hyperbar;
 public class Mediator(IServiceProvider provider) :
     IMediator
 {
-    private readonly ConditionalWeakTable<Type, dynamic> handlers = [];
+    private readonly ConditionalWeakTable<Type, dynamic> addedHandlers = [];
 
-    public ValueTask PublishAsync<TNotification>(TNotification notification,
+    public async ValueTask PublishAsync<TNotification>(TNotification notification,
         CancellationToken cancellationToken = default)
         where TNotification :
         INotification
@@ -16,7 +16,7 @@ public class Mediator(IServiceProvider provider) :
         List<INotificationHandler<TNotification>> handlers =
             provider.GetServices<INotificationHandler<TNotification>>().ToList();
 
-        foreach (KeyValuePair<Type, dynamic> handler in this.handlers)
+        foreach (KeyValuePair<Type, dynamic> handler in addedHandlers)
         {
             if (handler.Key == typeof(TNotification))
             {
@@ -26,14 +26,12 @@ public class Mediator(IServiceProvider provider) :
 
         if (handlers.Count == 0)
         {
-            return default;
         }
         else if (handlers.Count == 1)
         {
-            return handlers[0].Handle(notification, cancellationToken);
+            await handlers[0].Handle(notification, cancellationToken);
         }
 
-        return default;
     }
 
     public ValueTask<TResponse> SendAsync<TResponse>(IRequest<TResponse> request,
@@ -82,7 +80,7 @@ public class Mediator(IServiceProvider provider) :
                 if (interfaceType.GetGenericArguments() is { Length: 1 } arguments)
                 {
                     Type notificationType = arguments[0];
-                    handlers.Add(notificationType, subject);
+                    addedHandlers.Add(notificationType, subject);
                 }
             }
         }

Hyperbar/Views/CollectionChanged.cs

@@ -0,0 +1,5 @@
+using System.Collections;
+
+namespace Hyperbar;
+
+public record CollectionChanged<TCollection>(TCollection Items) : INotification where TCollection : IEnumerable;

Hyperbar/Views/ObservableCollectionViewModel.cs

@@ -3,19 +3,29 @@
 namespace Hyperbar;
 
 public class ObservableCollectionViewModel<TItem> :
-    ObservableCollection<TItem>
+    ObservableCollection<TItem>,
+    INotificationHandler<CollectionChanged<IEnumerable<TItem>>>
 {
     private readonly IServiceFactory serviceFactory;
-
-    public ObservableCollectionViewModel(IServiceFactory serviceFactory)
+    private SynchronizationContext? context;
+    public ObservableCollectionViewModel(IServiceFactory serviceFactory, 
+        IMediator mediator)
     {
+        context = SynchronizationContext.Current;
+
         this.serviceFactory = serviceFactory;
+        mediator.Subscribe(this);
     }
 
-    public ObservableCollectionViewModel(IServiceFactory serviceFactory, 
+    public ObservableCollectionViewModel(IServiceFactory serviceFactory,
+        IMediator mediator,
         IEnumerable<TItem> items)
     {
+        context = SynchronizationContext.Current;
+
         this.serviceFactory = serviceFactory;
+        mediator.Subscribe(this);
+
         AddRange(items);
     }
 
@@ -31,7 +41,7 @@ public class ObservableCollectionViewModel<TItem> :
         where T : TItem
     {
         T? item = serviceFactory.Create<T>(parameters);
-        Add(item);
+        context?.Post(state => Add(item), null);
 
         return item;
     }
@@ -41,7 +51,7 @@ public class ObservableCollectionViewModel<TItem> :
         TItem
     {
         T? item = serviceFactory.Create<T>();
-        Add(item);
+        context?.Post(state => Add(item), null);
 
         return item;
     }
@@ -50,12 +60,19 @@ public class ObservableCollectionViewModel<TItem> :
     {
         foreach (TItem? item in items)
         {
-            Add(item);
+            context?.Post(state => Add(item), null);
         }
     }
+
+    public ValueTask Handle(CollectionChanged<IEnumerable<TItem>> notification, 
+        CancellationToken cancellationToken)
+    {
+        context?.Post(state => Clear(), null);
+        AddRange(notification.Items);
+
+        return ValueTask.CompletedTask;
+    }
 }
 
-public class ObservableCollectionViewModel(IServiceFactory serviceFactory) :
-    ObservableCollectionViewModel<object>(serviceFactory)
-{
-}
+public class ObservableCollectionViewModel(IServiceFactory serviceFactory, IMediator mediator) :
+    ObservableCollectionViewModel<object>(serviceFactory, mediator);