Added C2S and S2C markings to class names.

SharpChat/C2SPacketHandlers/SendMessageC2SPacketHandler.cs

@@ -0,0 +1,89 @@
+using SharpChat.Config;
+using SharpChat.Events;
+using SharpChat.Snowflake;
+using System.Globalization;
+using System.Text;
+
+namespace SharpChat.C2SPacketHandlers {
+    public class SendMessageC2SPacketHandler(
+        RandomSnowflake randomSnowflake,
+        CachedValue<int> maxMsgLength
+    ) : C2SPacketHandler {
+        private readonly CachedValue<int> MaxMessageLength = maxMsgLength ?? throw new ArgumentNullException(nameof(maxMsgLength));
+
+        private List<IChatCommand> Commands { get; } = [];
+
+        public void AddCommand(IChatCommand command) {
+            Commands.Add(command ?? throw new ArgumentNullException(nameof(command)));
+        }
+
+        public void AddCommands(IEnumerable<IChatCommand> commands) {
+            Commands.AddRange(commands ?? throw new ArgumentNullException(nameof(commands)));
+        }
+
+        public bool IsMatch(ChatPacketHandlerContext ctx) {
+            return ctx.CheckPacketId("2");
+        }
+
+        public void Handle(ChatPacketHandlerContext ctx) {
+            string[] args = ctx.SplitText(3);
+
+            ChatUser? user = ctx.Connection.User;
+            string? messageText = args.ElementAtOrDefault(2);
+
+            if(user == null || !user.Can(ChatUserPermissions.SendMessage) || string.IsNullOrWhiteSpace(messageText))
+                return;
+
+            // Extra validation step, not necessary at all but enforces proper formatting in SCv1.
+            if(!long.TryParse(args[1], out long mUserId) || user.UserId != mUserId)
+                return;
+
+            ctx.Chat.ContextAccess.Wait();
+            try {
+                if(!ctx.Chat.UserLastChannel.TryGetValue(user.UserId, out ChatChannel? channel)
+                    && (channel is null || !ctx.Chat.IsInChannel(user, channel)))
+                    return;
+
+                if(user.Status != ChatUserStatus.Online)
+                    ctx.Chat.UpdateUser(user, status: ChatUserStatus.Online);
+
+                int maxMsgLength = MaxMessageLength;
+                StringInfo messageTextInfo = new(messageText);
+                if(Encoding.UTF8.GetByteCount(messageText) > (maxMsgLength * 10)
+                    || messageTextInfo.LengthInTextElements > maxMsgLength)
+                    messageText = messageTextInfo.SubstringByTextElements(0, Math.Min(messageTextInfo.LengthInTextElements, maxMsgLength));
+
+                messageText = messageText.Trim();
+
+#if DEBUG
+                Logger.Write($"<{ctx.Connection.Id} {user.UserName}> {messageText}");
+#endif
+
+                if(messageText.StartsWith('/')) {
+                    ChatCommandContext context = new(messageText, ctx.Chat, user, ctx.Connection, channel);
+                    foreach(IChatCommand cmd in Commands)
+                        if(cmd.IsMatch(context)) {
+                            cmd.Dispatch(context);
+                            return;
+                        }
+                }
+
+                ctx.Chat.DispatchEvent(new MessageCreateEvent(
+                    randomSnowflake.Next(),
+                    channel.Name,
+                    user.UserId,
+                    user.UserName,
+                    user.Colour,
+                    user.Rank,
+                    user.NickName,
+                    user.Permissions,
+                    DateTimeOffset.Now,
+                    messageText,
+                    false, false, false
+                ));
+            } finally {
+                ctx.Chat.ContextAccess.Release();
+            }
+        }
+    }
+}