refactors adminmenu a timid amount (#5095)

Co-authored-by: Paul <ritter.paul1+git@googlemail.com>
Co-authored-by: metalgearsloth <comedian_vs_clown@hotmail.com>

Content.Server/Administration/AdminSystem.cs

@@ -0,0 +1,107 @@
+using System;
+using System.Linq;
+using Content.Server.Administration.Managers;
+using Content.Server.Players;
+using Content.Shared.Administration;
+using Content.Shared.Administration.Events;
+using Robust.Server.GameObjects;
+using Robust.Server.Player;
+using Robust.Shared.Enums;
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+
+namespace Content.Server.Administration
+{
+    public class AdminSystem : EntitySystem
+    {
+        [Dependency] private readonly IPlayerManager _playerManager = default!;
+        [Dependency] private readonly IAdminManager _adminManager = default!;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            _playerManager.PlayerStatusChanged += OnPlayerStatusChanged;
+            SubscribeLocalEvent<PlayerAttachedEvent>(OnPlayerAttached);
+            SubscribeLocalEvent<PlayerDetachedEvent>(OnPlayerDetached);
+        }
+
+        private void OnPlayerDetached(PlayerDetachedEvent ev)
+        {
+            foreach (var admin in _adminManager.ActiveAdmins)
+            {
+                RaiseNetworkEvent(GetChangedEvent(ev.Player), admin.ConnectedClient);
+            }
+        }
+
+        private void OnPlayerAttached(PlayerAttachedEvent ev)
+        {
+            foreach (var admin in _adminManager.ActiveAdmins)
+            {
+                RaiseNetworkEvent(GetChangedEvent(ev.Player), admin.ConnectedClient);
+            }
+        }
+
+        public override void Shutdown()
+        {
+            base.Shutdown();
+            _playerManager.PlayerStatusChanged -= OnPlayerStatusChanged;
+        }
+
+        private PlayerInfoChangedEvent GetChangedEvent(IPlayerSession session)
+        {
+            return new()
+            {
+                PlayerInfo = new PlayerInfo(
+                    session.Name, session.AttachedEntity?.Name ?? string.Empty,
+                    session.ContentData()?.Mind?.AllRoles.Any(r => r.Antagonist) ?? false,
+                    session.AttachedEntity?.Uid ?? EntityUid.Invalid,
+                    session.UserId),
+            };
+        }
+
+        private void OnPlayerStatusChanged(object? sender, SessionStatusEventArgs e)
+        {
+            EntityEventArgs? args = null;
+            switch (e.NewStatus)
+            {
+                case SessionStatus.InGame:
+                case SessionStatus.Connected:
+                    args = GetChangedEvent(e.Session);
+                    break;
+                case SessionStatus.Disconnected:
+                    args = new PlayerInfoRemovalMessage {NetUserId = e.Session.UserId};
+                    break;
+            }
+
+            if(args == null) return;
+
+            foreach (var admin in _adminManager.ActiveAdmins)
+            {
+                RaiseNetworkEvent(args, admin.ConnectedClient);
+            }
+
+            if (e.NewStatus != SessionStatus.Disconnected && _adminManager.IsAdmin(e.Session))
+            {
+                SendFullPlayerList(e.Session);
+            }
+        }
+
+        private void SendFullPlayerList(IPlayerSession playerSession)
+        {
+            var ev = new FullPlayerListEvent();
+            ev.PlayersInfo.Clear();
+            foreach (var session in _playerManager.GetAllPlayers())
+            {
+                var name = session.Name;
+                var username = session.AttachedEntity?.Name ?? string.Empty;
+                var antag = session.ContentData()?.Mind?.AllRoles.Any(r => r.Antagonist) ?? false;
+                var uid = session.AttachedEntity?.Uid ?? EntityUid.Invalid;
+
+                ev.PlayersInfo.Add(new PlayerInfo(name, username, antag, uid, session.UserId));
+            }
+
+            RaiseNetworkEvent(ev, playerSession.ConnectedClient);
+        }
+    }
+}