Notifications in groups, and what is unread

The Notifications tab reads grouped notifications (/api/v2/notifications):
likes and boosts of one post, or follows of one hour, are one card naming
both accounts of a pair, or the newest and how many others, with their
avatars. A notification the stream tells joins its group and waits on top.
The tab's badge counts what is unread; opening the tab moves the
notifications marker to the newest shown, which reads it on PrivaPub.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw

Services/TimelineService.cs

@@ -78,25 +78,47 @@ namespace decePubClient.Services
 			};
 		}
 
+		/// <summary>Notifications folded into groups (/api/v2/notifications): likes and boosts of one post, follows of one
+		/// hour, each an item with its count and a few of its accounts. Paged by notification ids from the Link header.</summary>
 		async Task<WebResult> Notifications(string maxId, string minId, CancellationToken cancellationToken)
 		{
-			using var response = await httpService.Get(APIs.Mastodon.GET_Notifications, Paging([], maxId, minId), cancellationToken: cancellationToken);
+			using var response = await httpService.Get(APIs.Mastodon.GET_GroupedNotifications, Paging([], maxId, minId), cancellationToken: cancellationToken);
 			if (!response.IsSuccessStatusCode)
 				return await response.Content.ReadWebResult(response.StatusCode, localizer, cancellationToken);
 
-			var notifications = await response.MastodonReadFromJsonAsync<List<Notification>>(cancellationToken) ?? [];
+			var grouped = await response.MastodonReadFromJsonAsync<GroupedNotifications>(cancellationToken) ?? new GroupedNotifications();
+			var accounts = grouped.Accounts.DistinctBy(a => a.Id).ToDictionary(a => a.Id);
+			var statuses = grouped.Statuses.DistinctBy(s => s.Id).ToDictionary(s => s.Id);
 			var (nextMaxId, prevMinId) = response.PageCursors();
 			return new WebResult
 			{
 				Data = new FeedPage
 				{
-					Posts = [.. notifications.Select(FeedPost.Of)],
-					MaxId = notifications.Count < PageSize ? null : nextMaxId ?? notifications.LastOrDefault()?.Id,
-					MinId = prevMinId ?? notifications.FirstOrDefault()?.Id ?? minId
+					Posts = [.. grouped.NotificationGroups.Select(g => FeedPost.Of(g, accounts, statuses))],
+					MaxId = grouped.NotificationGroups.Count == 0 ? null : nextMaxId,
+					MinId = prevMinId ?? grouped.NotificationGroups.FirstOrDefault()?.MostRecentNotificationId ?? minId
 				}
 			};
 		}
 
+		/// <summary>How many groups of notifications are unread (newer than the notifications marker).</summary>
+		public async Task<int> UnreadNotifications(CancellationToken cancellationToken = default)
+		{
+			using var response = await httpService.Get(APIs.Mastodon.GET_UnreadNotifications, cancellationToken: cancellationToken);
+			return response.IsSuccessStatusCode ? (await response.MastodonReadFromJsonAsync<UnreadCount>(cancellationToken))?.Count ?? 0 : 0;
+		}
+
+		/// <summary>Moves the notifications marker to the newest one seen, which reads everything up to it.</summary>
+		public async Task<WebResult> ReadNotificationsUpTo(string notificationId, CancellationToken cancellationToken = default)
+		{
+			using var response = await httpService.Post(APIs.Mastodon.POST_Markers, new MarkersForm { Notifications = new MarkerForm { LastReadId = notificationId } },
+				cancellationToken: cancellationToken);
+			if (!response.IsSuccessStatusCode)
+				return await response.Content.ReadWebResult(response.StatusCode, localizer, cancellationToken);
+
+			return new WebResult();
+		}
+
 		/// <summary>Direct conversations, newest first; PrivaPub answers one page.</summary>
 		async Task<WebResult> Conversations(CancellationToken cancellationToken)
 		{