From fe871bf130a2d32345175c454fdb2dc17314e476 Mon Sep 17 00:00:00 2001
From: Laura Hausmann <laura@hausmann.dev>
Date: Fri, 9 Feb 2024 10:50:42 +0100
Subject: [PATCH] [backend/federation] Handle activities based on derived
 activity type instead of their type property

---
 .../ActivityPub/ActivityHandlerService.cs          | 14 +++++++-------
 .../Federation/ActivityPub/ActivityRenderer.cs     |  5 ++---
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityHandlerService.cs b/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityHandlerService.cs
index 022f6efb..5ac12cd1 100644
--- a/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityHandlerService.cs
+++ b/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityHandlerService.cs
@@ -31,39 +31,39 @@ public class ActivityHandlerService(
 
 		//TODO: validate inboxUserId
 
-		switch (activity.Type) {
-			case ASActivity.Types.Create: {
+		switch (activity) {
+			case ASCreate: {
 				//TODO: implement the rest
 				if (activity.Object is not ASNote note)
 					throw GracefulException.UnprocessableEntity("Create activity object is invalid");
 				await noteSvc.ProcessNoteAsync(note, activity.Actor);
 				return;
 			}
-			case ASActivity.Types.Follow: {
+			case ASFollow: {
 				if (activity.Object is not { } obj)
 					throw GracefulException.UnprocessableEntity("Follow activity object is invalid");
 				await FollowAsync(obj, activity.Actor, activity.Id);
 				return;
 			}
-			case ASActivity.Types.Unfollow: {
+			case ASUnfollow: {
 				if (activity.Object is not { } obj)
 					throw GracefulException.UnprocessableEntity("Unfollow activity object is invalid");
 				await UnfollowAsync(obj, activity.Actor);
 				return;
 			}
-			case ASActivity.Types.Accept: {
+			case ASAccept: {
 				if (activity.Object is not { } obj)
 					throw GracefulException.UnprocessableEntity("Accept activity object is invalid");
 				await AcceptAsync(obj, activity.Actor);
 				return;
 			}
-			case ASActivity.Types.Reject: {
+			case ASReject: {
 				if (activity.Object is not { } obj)
 					throw GracefulException.UnprocessableEntity("Reject activity object is invalid");
 				await RejectAsync(obj, activity.Actor);
 				return;
 			}
-			case ASActivity.Types.Undo: {
+			case ASUndo: {
 				//TODO: implement the rest
 				if (activity.Object is not ASActivity { Type: ASActivity.Types.Follow, Object: not null } undoActivity)
 					throw new NotImplementedException("Unsupported undo operation");
diff --git a/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityRenderer.cs b/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityRenderer.cs
index 433131ef..5685f65f 100644
--- a/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityRenderer.cs
+++ b/Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityRenderer.cs
@@ -11,10 +11,9 @@ public class ActivityRenderer(IOptions<Config.InstanceSection> config, UserRende
 	private string GenerateActivityId() =>
 		$"https://{config.Value.WebDomain}/activities/{Guid.NewGuid().ToString().ToLowerInvariant()}";
 
-	public static ASActivity RenderCreate(ASObject obj, ASObject actor) {
-		return new ASActivity {
+	public static ASCreate RenderCreate(ASObject obj, ASObject actor) {
+		return new ASCreate {
 			Id     = $"{obj.Id}#Create",
-			Type   = ASActivity.Types.Create,
 			Actor  = new ASActor { Id = actor.Id },
 			Object = obj
 		};