[backend/federation] Handle ASAnnounce activities

Iceshrimp.Backend/Controllers/Mastodon/Renderers/NoteRenderer.cs

@@ -164,7 +164,12 @@ public class NoteRenderer(
 		IEnumerable<Note> notes, User? user, List<AccountEntity>? accounts = null
 	)
 	{
-		var noteList = notes.ToList();
+		var noteList = notes.SelectMany<Note, Note?>(p => [p, p.Renote])
+		                    .Where(p => p != null)
+		                    .Cast<Note>()
+		                    .DistinctBy(p => p.Id)
+		                    .ToList();
+
 		accounts ??= await GetAccounts(noteList.Select(p => p.User));
 		var mentions    = await GetMentions(noteList);
 		var attachments = await GetAttachments(noteList);

Iceshrimp.Backend/Controllers/Mastodon/Renderers/NotificationRenderer.cs

@@ -14,9 +14,16 @@ public class NotificationRenderer(NoteRenderer noteRenderer, UserRenderer userRe
 	{
 		var dbNotifier = notification.Notifier ?? throw new GracefulException("Notification has no notifier");
 
+		var targetNote = notification.Type == Notification.NotificationType.Renote
+			? notification.Note?.Renote
+			: notification.Note;
+
+		if (notification.Note != null && targetNote == null)
+			throw new Exception("targetNote must not be null at this stage");
+
 		var note = notification.Note != null
-			? statuses?.FirstOrDefault(p => p.Id == notification.Note.Id) ??
+			? statuses?.FirstOrDefault(p => p.Id == targetNote!.Id) ??
-			  await noteRenderer.RenderAsync(notification.Note, user, accounts)
+			  await noteRenderer.RenderAsync(targetNote!, user, accounts)
 			: null;
 
 		var notifier = accounts?.FirstOrDefault(p => p.Id == dbNotifier.Id) ??
@@ -45,11 +52,17 @@ public class NotificationRenderer(NoteRenderer noteRenderer, UserRenderer userRe
 		var accounts = await noteRenderer.GetAccounts(notificationList.Where(p => p.Notifier != null)
 		                                                              .Select(p => p.Notifier)
 		                                                              .Concat(notificationList.Select(p => p.Notifiee))
+		                                                              .Concat(notificationList
+		                                                                      .Select(p => p.Note?.Renote?.User)
+		                                                                      .Where(p => p != null))
 		                                                              .Cast<User>()
 		                                                              .DistinctBy(p => p.Id));
 
 		var notes = await noteRenderer.RenderManyAsync(notificationList.Where(p => p.Note != null)
 		                                                               .Select(p => p.Note)
+		                                                               .Concat(notificationList
+		                                                                       .Select(p => p.Note?.Renote)
+		                                                                       .Where(p => p != null))
 		                                                               .Cast<Note>()
 		                                                               .DistinctBy(p => p.Id), user, accounts);
 

Iceshrimp.Backend/Controllers/Mastodon/Schemas/Entities/NotificationEntity.cs

@@ -22,8 +22,8 @@ public class NotificationEntity : IEntity
 			NotificationType.Follow                => "follow",
 			NotificationType.Mention               => "mention",
 			NotificationType.Reply                 => "mention",
-			NotificationType.Renote                => "renote",
+			NotificationType.Renote                => "reblog",
-			NotificationType.Quote                 => "reblog",
+			NotificationType.Quote                 => "status",
 			NotificationType.Like                  => "favourite",
 			NotificationType.PollEnded             => "poll",
 			NotificationType.FollowRequestReceived => "follow_request",
@@ -39,8 +39,7 @@ public class NotificationEntity : IEntity
 		{
 			"follow"         => [NotificationType.Follow],
 			"mention"        => [NotificationType.Mention, NotificationType.Reply],
-			"renote"         => [NotificationType.Renote],
+			"reblog"         => [NotificationType.Renote, NotificationType.Quote],
-			"reblog"         => [NotificationType.Quote],
 			"favourite"      => [NotificationType.Like],
 			"poll"           => [NotificationType.PollEnded],
 			"follow_request" => [NotificationType.FollowRequestReceived],

Iceshrimp.Backend/Core/Extensions/QueryableExtensions.cs

@@ -253,7 +253,8 @@ public static class QueryableExtensions
 	)
 	{
 		var list = (await notes.ToListAsync())
-			.EnforceRenoteReplyVisibility();
+			.EnforceRenoteReplyVisibility()
+			.ToList();
 		return (await renderer.RenderManyAsync(list, user)).ToList();
 	}
 

Iceshrimp.Backend/Core/Federation/ActivityPub/ActivityHandlerService.cs

@@ -227,6 +227,16 @@ public class ActivityHandlerService(
 				await notificationSvc.GenerateBiteNotification(dbBite);
 				return;
 			}
+			case ASAnnounce announce:
+			{
+				if (announce.Object is not ASNote note)
+					throw GracefulException.UnprocessableEntity("Invalid or unsupported announce object");
+
+				var dbNote = await noteSvc.ResolveNoteAsync(note.Id, note.VerifiedFetch ? note : null);
+				var renote = await noteSvc.CreateNoteAsync(resolvedActor, announce.GetVisibility(activity.Actor), renote: dbNote);
+				await notificationSvc.GenerateRenoteNotification(renote);
+				return;
+			}
 			default:
 				throw new NotImplementedException($"Activity type {activity.Type} is unknown");
 		}

Iceshrimp.Backend/Core/Federation/ActivityPub/ObjectResolver.cs

@@ -31,7 +31,7 @@ public class ObjectResolver(
 		}
 
 		if (baseObj.Id.StartsWith($"https://{config.Value.WebDomain}/notes/"))
-			return new ASNote { Id = baseObj.Id };
+			return new ASNote { Id = baseObj.Id, VerifiedFetch = true };
 		if (baseObj.Id.StartsWith($"https://{config.Value.WebDomain}/users/"))
 			return new ASActor { Id = baseObj.Id };
 
@@ -42,14 +42,17 @@ public class ObjectResolver(
 		}
 
 		if (await db.Notes.AnyAsync(p => p.Uri == baseObj.Id))
-			return new ASNote { Id = baseObj.Id };
+			return new ASNote { Id = baseObj.Id, VerifiedFetch = true };
 		if (await db.Users.AnyAsync(p => p.Uri == baseObj.Id))
 			return new ASActor { Id = baseObj.Id };
 
 		try
 		{
 			var result      = await fetchSvc.FetchActivityAsync(baseObj.Id);
-			return result.FirstOrDefault();
+			var resolvedObj = result.FirstOrDefault();
+			if (resolvedObj is not ASNote note) return resolvedObj;
+			note.VerifiedFetch = true;
+			return note;
 		}
 		catch (Exception e)
 		{

Iceshrimp.Backend/Core/Federation/ActivityStreams/Types/ASActivity.cs

@@ -1,4 +1,5 @@
 using Iceshrimp.Backend.Core.Configuration;
+using Iceshrimp.Backend.Core.Database.Tables;
 using J = Newtonsoft.Json.JsonPropertyAttribute;
 using JC = Newtonsoft.Json.JsonConverterAttribute;
 using JI = Newtonsoft.Json.JsonIgnoreAttribute;
@@ -24,6 +25,7 @@ public class ASActivity : ASObject
 		public const string Create   = $"{Ns}#Create";
 		public const string Update   = $"{Ns}#Update";
 		public const string Delete   = $"{Ns}#Delete";
+		public const string Announce = $"{Ns}#Announce";
 		public const string Follow   = $"{Ns}#Follow";
 		public const string Unfollow = $"{Ns}#Unfollow";
 		public const string Accept   = $"{Ns}#Accept";
@@ -59,6 +61,29 @@ public class ASCreate : ASActivity
 	}
 }
 
+public class ASAnnounce : ASActivity
+{
+	public ASAnnounce() => Type = Types.Announce;
+
+	[J($"{Constants.ActivityStreamsNs}#to")]
+	public List<ASObjectBase>? To { get; set; }
+
+	[J($"{Constants.ActivityStreamsNs}#cc")]
+	public List<ASObjectBase>? Cc { get; set; }
+	
+	public Note.NoteVisibility GetVisibility(ASActor actor)
+	{
+		if (To?.Any(p => p.Id == $"{Constants.ActivityStreamsNs}#Public") ?? false)
+			return Note.NoteVisibility.Public;
+		if (Cc?.Any(p => p.Id == $"{Constants.ActivityStreamsNs}#Public") ?? false)
+			return Note.NoteVisibility.Home;
+		if (To?.Any(p => p.Id is not null && p.Id == (actor.Followers?.Id ?? actor.Id + "/followers")) ?? false)
+			return Note.NoteVisibility.Followers;
+
+		return Note.NoteVisibility.Specified;
+	}
+}
+
 public class ASDelete : ASActivity
 {
 	public ASDelete() => Type = Types.Delete;

Iceshrimp.Backend/Core/Federation/ActivityStreams/Types/ASNote.cs

@@ -59,6 +59,8 @@ public class ASNote : ASObject
 	[JC(typeof(ASAttachmentConverter))]
 	public List<ASAttachment>? Attachments { get; set; }
 
+	public bool VerifiedFetch = false;
+
 	public Note.NoteVisibility GetVisibility(ASActor actor)
 	{
 		if (To.Any(p => p.Id == $"{Constants.ActivityStreamsNs}#Public"))

Iceshrimp.Backend/Core/Federation/ActivityStreams/Types/ASObject.cs

@@ -52,6 +52,7 @@ public class ASObject : ASObjectBase
 						ASActivity.Types.Undo      => token.ToObject<ASUndo>(),
 						ASActivity.Types.Like      => token.ToObject<ASLike>(),
 						ASActivity.Types.Bite      => token.ToObject<ASBite>(),
+						ASActivity.Types.Announce  => token.ToObject<ASAnnounce>(),
 						_                          => token.ToObject<ASObject>()
 					};
 				case JTokenType.Array:

Iceshrimp.Backend/Core/Services/NoteService.cs

@@ -91,11 +91,17 @@ public class NoteService(
 
 		user.NotesCount++;
 		if (reply != null) reply.RepliesCount++;
+		if (renote != null && !note.IsQuote)
+			if (!db.Notes.Any(p => p.UserId == user.Id && p.RenoteId == renote.Id && p.IsPureRenote))
+				renote.RenoteCount++;
+
 		await db.AddAsync(note);
 		await db.SaveChangesAsync();
 		eventSvc.RaiseNotePublished(this, note);
 		await notificationSvc.GenerateMentionNotifications(note, mentionedLocalUserIds);
 
+		if (user.Host != null) return note;
+
 		var actor    = userRenderer.RenderLite(user);
 		var obj      = await noteRenderer.RenderAsync(note, mentions);
 		var activity = ActivityPub.ActivityRenderer.RenderCreate(obj, actor);

Iceshrimp.Backend/Core/Services/NotificationService.cs

@@ -179,4 +179,27 @@ public class NotificationService(
 		await db.SaveChangesAsync();
 		eventSvc.RaiseNotification(this, notification);
 	}
+
+	[SuppressMessage("ReSharper", "EntityFramework.UnsupportedServerSideFunctionCall", Justification = "Projectables")]
+	public async Task GenerateRenoteNotification(Note note)
+	{
+		if (note.Renote is not { UserHost: null }) return;
+		if (!note.VisibilityIsPublicOrHome &&
+		    await db.Notes.AnyAsync(p => p.Id == note.Id && p.IsVisibleFor(note.Renote.User)))
+			return;
+
+		var notification = new Notification
+		{
+			Id        = IdHelpers.GenerateSlowflakeId(),
+			CreatedAt = DateTime.UtcNow,
+			Note      = note,
+			Notifiee  = note.Renote.User,
+			Notifier  = note.User,
+			Type      = Notification.NotificationType.Renote
+		};
+
+		await db.AddAsync(notification);
+		await db.SaveChangesAsync();
+		eventSvc.RaiseNotification(this, notification);
+	}
 }