sharp-chat/SharpChat/Packet/ContextUsersPacket.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace SharpChat.Packet {
    public class ContextUsersPacket : ServerPacket {
        public IEnumerable<ChatUser> Users { get; private set; }

        public ContextUsersPacket(IEnumerable<ChatUser> users) {
            Users = users?.Where(u => u != null) ?? throw new ArgumentNullException(nameof(users));
        }

        public override string Pack() {
            StringBuilder sb = new();

            sb.AppendFormat("7\t0\t{0}", Users.Count());

            foreach(ChatUser user in Users)
                sb.AppendFormat(
                    "\t{0}\t{1}\t{2}\t{3} {4} {5} {6} {7}\t{8}",
                    user.UserId,
                    user.LegacyNameWithStatus,
                    user.Colour,
                    user.Rank,
                    user.Can(ChatUserPermissions.KickUser) ? 1 : 0,
                    user.Can(ChatUserPermissions.ViewLogs) ? 1 : 0,
                    user.Can(ChatUserPermissions.SetOwnNickname) ? 1 : 0,
                    user.Can(ChatUserPermissions.CreateChannel | ChatUserPermissions.SetChannelPermanent, true) ? 2 : (
                        user.Can(ChatUserPermissions.CreateChannel) ? 1 : 0
                    ),
                    1 // visibility flag
                );

            return sb.ToString();
        }
    }
}