Keep username changes

GameServer/Server/Packet/Recv/Login/HandlerReqLogin.cs

@@ -43,6 +43,8 @@ public class HandlerReqLogin : Handler
         connection.State = SessionStateEnum.WAITING_FOR_LOGIN;
         var pd = DatabaseHelper.GetInstance<PlayerGameData>(account.Uid);
         connection.Player = pd == null ? new PlayerInstance(account.Uid) : new PlayerInstance(pd);
+        if (connection.Player.Data.EnsureDisplayName())
+            DatabaseHelper.UpdateInstance(connection.Player.Data);
 
         connection.DebugFile = Path.Combine(ConfigManager.Config.Path.LogPath, "Debug/", $"{account.Uid}/",
             $"Debug-{DateTime.Now:yyyy-MM-dd HH-mm-ss}.log");

GameServer/Server/Packet/Recv/Player/HandlerReqRename.cs

@@ -1,4 +1,6 @@
-using MikuSB.Proto;
+using Google.Protobuf;
+using MikuSB.Database;
+using MikuSB.Proto;
 
 namespace MikuSB.GameServer.Server.Packet.Recv.Login;
 
@@ -7,6 +9,57 @@ public class HandlerReqRename : Handler
 {
     public override async Task OnHandle(Connection connection, byte[] data, ushort seqNo)
     {
+        var player = connection.Player;
+        if (player != null)
+        {
+            var requestedName = ParseDisplayName(data);
+            player.SetDisplayName(requestedName);
+            DatabaseHelper.UpdateInstance(player.Data);
+            await player.OnHeartBeat();
+        }
+
         await connection.SendPacket(CmdIds.RspRename);
     }
+
+    private static string? ParseDisplayName(byte[] data)
+    {
+        if (data.Length == 0)
+            return null;
+
+        try
+        {
+            var input = new CodedInputStream(data);
+            while (!input.IsAtEnd)
+            {
+                var tag = input.ReadTag();
+                if (tag == 0)
+                    break;
+
+                if (WireFormat.GetTagWireType(tag) == WireFormat.WireType.LengthDelimited)
+                {
+                    var value = input.ReadString();
+                    if (!string.IsNullOrWhiteSpace(value))
+                        return value;
+                }
+                else
+                {
+                    input.SkipLastField();
+                }
+            }
+        }
+        catch
+        {
+            // Fall back to raw UTF-8 payload handling below.
+        }
+
+        try
+        {
+            var rawText = System.Text.Encoding.UTF8.GetString(data).Trim('\0', ' ', '\r', '\n', '\t');
+            return string.IsNullOrWhiteSpace(rawText) ? null : rawText;
+        }
+        catch
+        {
+            return null;
+        }
+    }
 }