WIP to allow mediter handlers to be subscribed to

Toolkit.Foundation/CommandValueViewModel.cs

@@ -6,7 +6,7 @@ public partial class CommandValueViewModel<TValue>(IServiceProvider provider,
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber,
+    ISubscription subscriber,
     IDisposer disposer) :
     ValueViewModel<TValue>(provider, factory, mediator, publisher, subscriber, disposer)
 {

Toolkit.Foundation/CommandViewModel.cs

@@ -6,7 +6,7 @@ public partial class CommandViewModel(IServiceProvider provider,
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber,
+    ISubscription subscriber,
     IDisposer disposer) :
     ObservableViewModel(provider, factory, mediator, publisher, subscriber, disposer)
 {

Toolkit.Foundation/ComponentBuilder.cs

@@ -27,11 +27,14 @@ public class ComponentBuilder :
                     new ServiceFactory((type, parameters) =>
                         ActivatorUtilities.CreateInstance(provider, type, parameters!)));
 
-                services.AddScoped<SubscriptionCollection>();
-                services.AddScoped<ISubscriptionManager, SubscriptionManager>();
                 services.AddSingleton<IDisposer, Disposer>();
 
-                services.AddTransient<ISubscriber, Subscriber>();
+                services.AddScoped<SubscriptionCollection>();
+
+                services.AddTransient<IHandlerProvider, HandlerProvider>();
+                services.AddTransient<ISubscription, Subscription>();
+
+                services.AddTransient<ISubscription, Subscription>();
                 services.AddTransient<IPublisher, Publisher>();
 
                 services.AddTransient<IMediator, Mediator>();

Toolkit.Foundation/ComponentConfigurationViewModel.cs

@@ -12,7 +12,7 @@ public partial class ComponentConfigurationViewModel<TConfiguration, TValue, THe
         IServiceFactory factory,
         IMediator mediator,
         IPublisher publisher,
-        ISubscriber subscriber,
+        ISubscription subscriber,
         IDisposer disposer,
         THeader header,
         TDescription description,
@@ -30,7 +30,7 @@ public partial class ComponentConfigurationViewModel<TConfiguration, TValue, TAc
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber,
+    ISubscription subscriber,
     IDisposer disposer,
     TAction action,
     TConfiguration configuration,
@@ -72,7 +72,7 @@ public partial class ComponentConfigurationViewModel<TConfiguration, TValue, TDe
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber,
+    ISubscription subscriber,
     IDisposer disposer,
     TAction action,
     TDescription description,

Toolkit.Foundation/DefaultHostBuilder.cs

@@ -26,9 +26,11 @@ public class DefaultHostBuilder :
                 services.AddSingleton<IDisposer, Disposer>();
 
                 services.AddScoped<SubscriptionCollection>();
-                services.AddTransient<ISubscriptionManager, SubscriptionManager>();
 
-                services.AddTransient<ISubscriber, Subscriber>();
+                services.AddTransient<IHandlerProvider, HandlerProvider>();
+                services.AddTransient<ISubscription, Subscription>();
+
+                services.AddTransient<ISubscription, Subscription>();
 
                 services.AddTransient<IPublisher, Publisher>();
                 services.AddTransient<IMediator, Mediator>();

Toolkit.Foundation/HandlerProvider.cs

@@ -0,0 +1,26 @@
+namespace Toolkit.Foundation;
+
+public class HandlerProvider(SubscriptionCollection subscriptions) : 
+    IHandlerProvider
+{
+    public IEnumerable<object?> Get(Type type,
+        object key)
+    {
+        string subscriptionKey = $"{(key is not null ? $"{key}:" : "")}{type}";
+        if (subscriptions.TryGetValue(subscriptionKey, out List<WeakReference>? subscribers))
+        {
+            foreach (WeakReference weakRef in subscribers.ToArray())
+            {
+                object? target = weakRef.Target;
+                if (target != null)
+                {
+                    yield return target;
+                }
+                else
+                {
+                    subscribers.Remove(weakRef);
+                }
+            }
+        }
+    }
+}

Toolkit.Foundation/IHandlerProvider.cs

@@ -0,0 +1,8 @@
+
+namespace Toolkit.Foundation
+{
+    public interface IHandlerProvider
+    {
+        IEnumerable<object?> Get(Type type, object key);
+    }
+}

Toolkit.Foundation/ISubscription.cs

@@ -1,8 +1,8 @@
 namespace Toolkit.Foundation;
 
-public interface ISubscriber
+public interface ISubscription
 {
-    void Remove(object subscriber);
-
     void Add(object subscriber);
+
+    void Remove(object subscriber);
 }

Toolkit.Foundation/ISubscriptionManager.cs

@@ -1,10 +0,0 @@
-namespace Toolkit.Foundation;
-
-public interface ISubscriptionManager
-{
-    IEnumerable<object?> GetHandlers(Type notificationType, object key);
-
-    void Remove(object subscriber);
-
-    void Add(object subscriber);
-}

Toolkit.Foundation/ObservableCollectionViewModel.cs

@@ -41,7 +41,7 @@ public partial class ObservableCollectionViewModel<TViewModel> :
         IServiceFactory factory,
         IMediator mediator,
         IPublisher publisher,
-        ISubscriber subscriber,
+        ISubscription subscriber,
         IDisposer disposer)
     {
         Provider = provider;
@@ -59,7 +59,7 @@ public partial class ObservableCollectionViewModel<TViewModel> :
         IServiceFactory factory,
         IMediator mediator,
         IPublisher publisher,
-        ISubscriber subscriber,
+        ISubscription subscriber,
         IDisposer disposer,
         IEnumerable<TViewModel> items)
     {
@@ -459,7 +459,7 @@ public partial class ObservableCollectionViewModel<TValue, TViewModel>(IServiceP
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber, IDisposer disposer) : ObservableCollectionViewModel<TViewModel>(provider, factory, mediator, publisher, subscriber, disposer)
+    ISubscription subscriber, IDisposer disposer) : ObservableCollectionViewModel<TViewModel>(provider, factory, mediator, publisher, subscriber, disposer)
     where TViewModel : notnull
 {
     [ObservableProperty]
@@ -470,6 +470,6 @@ public class ObservableCollectionViewModel(IServiceProvider provider,
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber,
+    ISubscription subscriber,
     IDisposer disposer) :
     ObservableCollectionViewModel<IDisposable>(provider, factory, mediator, publisher, subscriber, disposer);

Toolkit.Foundation/ObservableViewModel.cs

@@ -19,7 +19,7 @@ public partial class ObservableViewModel :
         IServiceFactory factory,
         IMediator mediator,
         IPublisher publisher,
-        ISubscriber subscriber,
+        ISubscription subscriber,
         IDisposer disposer)
     {
         Provider = provider;
@@ -80,7 +80,7 @@ public partial class ObservableViewModel<TValue>(IServiceProvider provider,
     IServiceFactory factory,
     IMediator mediator, 
     IPublisher publisher, 
-    ISubscriber subscriber, 
+    ISubscription subscriber, 
     IDisposer disposer) : ObservableViewModel(provider, factory, mediator, publisher, subscriber, disposer)
     where TValue : notnull
 {
@@ -92,7 +92,7 @@ public partial class ObservableViewModel<TKey, TValue>(IServiceProvider provider
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber,
+    ISubscription subscriber,
     IDisposer disposer,
     TValue? value = null) : ObservableViewModel(provider, factory, mediator, publisher, subscriber, disposer)
     where TValue : class

Toolkit.Foundation/Publisher.cs

@@ -3,7 +3,7 @@ using System.Reflection;
 
 namespace Toolkit.Foundation;
 
-public class Publisher(ISubscriptionManager subscriptionManager,
+public class Publisher(IHandlerProvider handlerProvider,
     IServiceProvider provider,
     IDispatcher dispatcher) :
     IPublisher
@@ -29,8 +29,8 @@ public class Publisher(ISubscriptionManager subscriptionManager,
         List<object?> handlers = provider.GetServices(typeof(NotificationHandlerWrapper<>)
             .MakeGenericType(notificationType)).ToList();
 
-        foreach (object? handler in subscriptionManager
-            .GetHandlers(notificationType, key!))
+        foreach (object? handler in handlerProvider
+            .Get(notificationType, key!))
         {
             handlers.Add(handler);
         }

Toolkit.Foundation/Subscriber.cs

@@ -1,11 +0,0 @@
-namespace Toolkit.Foundation;
-
-public class Subscriber(ISubscriptionManager subscriptionManager) :
-    ISubscriber
-{
-    public void Remove(object subscriber) =>
-        subscriptionManager.Remove(subscriber);
-
-    public void Add(object subscriber) =>
-        subscriptionManager.Add(subscriber);
-}

Toolkit.Foundation/Subscription.cs

@@ -2,27 +2,26 @@
 
 namespace Toolkit.Foundation;
 
-public class SubscriptionManager(SubscriptionCollection subscriptions, 
-    IDisposer disposer) : 
-    ISubscriptionManager
+public class Subscription(SubscriptionCollection subscriptions,
+    IDisposer disposer) :
+    ISubscription
 {
-    public IEnumerable<object?> GetHandlers(Type notificationType, 
-        object key)
+    public void Add(object subscriber)
     {
-        string subscriptionKey = $"{(key is not null ? $"{key}:" : "")}{notificationType}";
-        if (subscriptions.TryGetValue(subscriptionKey, out List<WeakReference>? subscribers))
+        Type handlerType = subscriber.GetType();
+        object? key = GetKeyFromHandler(subscriber);
+        foreach (Type interfaceType in GetHandlerInterfaces(handlerType))
         {
-            foreach (WeakReference weakRef in subscribers.ToArray())
+            if (interfaceType.GetGenericArguments().FirstOrDefault() is Type argumentType)
             {
-                object? target = weakRef.Target;
-                if (target != null)
+                string subscriptionKey = $"{(key is not null ? $"{key}:" : "")}{argumentType}";
+                subscriptions.AddOrUpdate(subscriptionKey, _ => new List<WeakReference> { new(subscriber) }, (_, collection) =>
                 {
-                    yield return target;
-                }
-                else
-                {
-                    subscribers.Remove(weakRef);
-                }
+                    collection.Add(new WeakReference(subscriber));
+                    return collection;
+                });
+
+                disposer.Add(subscriber, Disposable.Create(() => RemoveSubscriber(subscriber, argumentType)));
             }
         }
     }
@@ -50,27 +49,8 @@ public class SubscriptionManager(SubscriptionCollection subscriptions,
         }
     }
 
-    public void Add(object subscriber)
-    {
-        Type handlerType = subscriber.GetType();
-        object? key = GetKeyFromHandler(subscriber);
-        foreach (Type interfaceType in GetHandlerInterfaces(handlerType))
-        {
-            if (interfaceType.GetGenericArguments().FirstOrDefault() is Type argumentType)
-            {
-                string subscriptionKey = $"{(key is not null ? $"{key}:" : "")}{argumentType}";
-                subscriptions.AddOrUpdate(subscriptionKey, _ => new List<WeakReference> { new(subscriber) }, (_, collection) =>
-                {
-                    collection.Add(new WeakReference(subscriber));
-                    return collection;
-                });
 
-                disposer.Add(subscriber, Disposable.Create(() => RemoveSubscriber(subscriber, argumentType)));
-            }
-        }
-    }
-
-    private void RemoveSubscriber(object subscriber, 
+    private void RemoveSubscriber(object subscriber,
         Type argumentType)
     {
         string subscriptionKey = $"{argumentType}";
@@ -91,11 +71,11 @@ public class SubscriptionManager(SubscriptionCollection subscriptions,
         }
     }
 
-    private object? GetKeyFromHandler(object handler) => 
+    private object? GetKeyFromHandler(object handler) =>
         handler.GetAttribute<NotificationAttribute>() is NotificationAttribute attribute
             ? handler.GetPropertyValue(() => attribute.Key) is { } value ? value : attribute.Key : null;
 
     private IEnumerable<Type> GetHandlerInterfaces(Type handlerType) =>
         handlerType.GetInterfaces().Where(interfaceType => interfaceType.IsGenericType &&
             interfaceType.GetGenericTypeDefinition() == typeof(INotificationHandler<>));
-}
+}

Toolkit.Foundation/ValueViewModel.cs

@@ -6,7 +6,7 @@ public partial class ValueViewModel<TValue>(IServiceProvider provider,
     IServiceFactory factory,
     IMediator mediator,
     IPublisher publisher,
-    ISubscriber subscriber,
+    ISubscription subscriber,
     IDisposer disposer) :
     ObservableViewModel(provider, factory, mediator, publisher, subscriber, disposer)
 {