Implement missing API code for channel read state (#7425)

Implement missing API code for channel read state

osu.Game/Online/API/Requests/MarkChannelAsReadRequest.cs

@@ -0,0 +1,30 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Net.Http;
+using osu.Framework.IO.Network;
+using osu.Game.Online.Chat;
+
+namespace osu.Game.Online.API.Requests
+{
+    public class MarkChannelAsReadRequest : APIRequest
+    {
+        private readonly Channel channel;
+        private readonly Message message;
+
+        public MarkChannelAsReadRequest(Channel channel, Message message)
+        {
+            this.channel = channel;
+            this.message = message;
+        }
+
+        protected override string Target => $"chat/channels/{channel.Id}/mark-as-read/{message.Id}";
+
+        protected override WebRequest CreateWebRequest()
+        {
+            var req = base.CreateWebRequest();
+            req.Method = HttpMethod.Put;
+            return req;
+        }
+    }
+}

osu.Game/Online/Chat/Channel.cs

@@ -36,6 +36,11 @@ namespace osu.Game.Online.Chat
         /// </summary>
         public readonly SortedList<Message> Messages = new SortedList<Message>(Comparer<Message>.Default);
 
+        /// <summary>
+        /// Contains all the messages that weren't read by the user.
+        /// </summary>
+        public IEnumerable<Message> UnreadMessages => Messages.Where(m => LastReadId < m.Id);
+
         /// <summary>
         /// Contains all the messages that are still pending for submission to the server.
         /// </summary>
@@ -75,6 +80,9 @@ namespace osu.Game.Online.Chat
         [JsonProperty(@"last_message_id")]
         public long? LastMessageId;
 
+        [JsonProperty(@"last_read_id")]
+        public long? LastReadId;
+
         /// <summary>
         /// Signalles if the current user joined this channel or not. Defaults to false.
         /// </summary>

osu.Game/Online/Chat/ChannelManager.cs

@@ -445,6 +445,28 @@ namespace osu.Game.Online.Chat
             return tcs.Task;
         }
 
+        /// <summary>
+        /// Marks the <paramref name="channel"/> as read
+        /// </summary>
+        /// <param name="channel">The channel that will be marked as read</param>
+        public void MarkChannelAsRead(Channel channel)
+        {
+            if (channel.LastMessageId == channel.LastReadId)
+                return;
+
+            var message = channel.Messages.LastOrDefault();
+
+            if (message == null)
+                return;
+
+            var req = new MarkChannelAsReadRequest(channel, message);
+
+            req.Success += () => channel.LastReadId = message.Id;
+            req.Failure += e => Logger.Error(e, $"Failed to mark channel {channel} up to '{message}' as read");
+
+            api.Queue(req);
+        }
+
         [BackgroundDependencyLoader]
         private void load(IAPIProvider api)
         {

osu.Game/Overlays/ChatOverlay.cs

@@ -279,6 +279,10 @@ namespace osu.Game.Overlays
                 currentChannelContainer.Clear(false);
                 currentChannelContainer.Add(loaded);
             }
+
+            // mark channel as read when channel switched
+            if (e.NewValue.Messages.Any())
+                channelManager.MarkChannelAsRead(e.NewValue);
         }
 
         private float startDragChatHeight;