using SharpChat.SockChat.S2CPackets; using System.Globalization; using System.Text; namespace SharpChat.ClientCommands; public class NickClientCommand : ClientCommand { private const int MAX_GRAPHEMES = 16; private const int MAX_BYTES = MAX_GRAPHEMES * 10; public bool IsMatch(ClientCommandContext ctx) { return ctx.NameEquals("nick"); } public async Task Dispatch(ClientCommandContext ctx) { long msgId = ctx.Chat.RandomSnowflake.Next(); bool setOthersNick = ctx.User.Can(UserPermissions.SetOthersNickname); if(!setOthersNick && !ctx.User.Can(UserPermissions.SetOwnNickname)) { await ctx.Chat.SendTo(ctx.User, new CommandResponseS2CPacket(msgId, LCR.COMMAND_NOT_ALLOWED, true, $"/{ctx.Name}")); return; } User? targetUser = null; int offset = 0; if(setOthersNick && long.TryParse(ctx.Args.FirstOrDefault(), out long targetUserId) && targetUserId > 0) { targetUser = ctx.Chat.Users.FirstOrDefault(u => u.UserId == targetUserId.ToString()); ++offset; } targetUser ??= ctx.User; if(ctx.Args.Length < offset) { await ctx.Chat.SendTo(ctx.User, new CommandResponseS2CPacket(msgId, LCR.COMMAND_FORMAT_ERROR)); return; } string nickStr = string.Join('_', ctx.Args.Skip(offset)) .Replace("\n", string.Empty).Replace("\r", string.Empty) .Replace("\f", string.Empty).Replace("\t", string.Empty) .Replace(' ', '_').Trim(); if(nickStr == targetUser.UserName) nickStr = string.Empty; else if(string.IsNullOrEmpty(nickStr)) nickStr = string.Empty; else { StringInfo nsi = new(nickStr); if(Encoding.UTF8.GetByteCount(nickStr) > MAX_BYTES || nsi.LengthInTextElements > MAX_GRAPHEMES) nickStr = nsi.SubstringByTextElements(0, Math.Min(nsi.LengthInTextElements, MAX_GRAPHEMES)).Trim(); } if(!string.IsNullOrWhiteSpace(nickStr) && ctx.Chat.Users.Any(u => u.NameEquals(nickStr))) { await ctx.Chat.SendTo(ctx.User, new CommandResponseS2CPacket(msgId, LCR.NAME_IN_USE, true, nickStr)); return; } string? previousName = targetUser.UserId == ctx.User.UserId ? (targetUser.NickName ?? targetUser.UserName) : null; await ctx.Chat.UpdateUser(targetUser, nickName: nickStr, silent: previousName == null); } }