Turns GameTicker into an EntitySystem. (#4197)

* GameTicker turned into an EntitySystem

* Turns ClientGameTicker into an EntitySystem, turn NetMessages into events

* Change event names to be more consistent with the rest.

* YAML linter uses the dummy gameticker CVar override.

* Fix game ticker initialization order

* Dummy ticker won't spawn players.

* Fix character creation test

Content.Server/GameTicking/GameTicker.Lobby.cs

@@ -0,0 +1,139 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Content.Shared.GameTicking;
+using Robust.Server.Player;
+using Robust.Shared.Localization;
+using Robust.Shared.Network;
+using Robust.Shared.Player;
+using Robust.Shared.Players;
+using Robust.Shared.ViewVariables;
+
+namespace Content.Server.GameTicking
+{
+    public partial class GameTicker
+    {
+        [ViewVariables]
+        private readonly Dictionary<IPlayerSession, LobbyPlayerStatus> _playersInLobby = new();
+
+        [ViewVariables]
+        private TimeSpan _roundStartTime;
+
+        [ViewVariables]
+        private TimeSpan _pauseTime;
+
+        [ViewVariables]
+        public bool Paused { get; set; }
+
+        [ViewVariables]
+        private bool _roundStartCountdownHasNotStartedYetDueToNoPlayers;
+
+        private void UpdateInfoText()
+        {
+            RaiseNetworkEvent(GetInfoMsg(), Filter.Empty().AddPlayers(_playersInLobby.Keys));
+        }
+
+        private string GetInfoText()
+        {
+            if (Preset == null)
+            {
+                return string.Empty;
+            }
+
+            var gmTitle = Preset.ModeTitle;
+            var desc = Preset.Description;
+            return Loc.GetString(@"Hi and welcome to [color=white]Space Station 14![/color]
+
+The current game mode is: [color=white]{0}[/color].
+[color=yellow]{1}[/color]", gmTitle, desc);
+        }
+
+        private TickerLobbyReadyEvent GetStatusSingle(ICommonSession player, LobbyPlayerStatus status)
+        {
+            return new (new Dictionary<NetUserId, LobbyPlayerStatus> { { player.UserId, status } });
+        }
+
+        private TickerLobbyReadyEvent GetPlayerStatus()
+        {
+            var players = new Dictionary<NetUserId, LobbyPlayerStatus>();
+            foreach (var player in _playersInLobby.Keys)
+            {
+                _playersInLobby.TryGetValue(player, out var status);
+                players.Add(player.UserId, status);
+            }
+            return new TickerLobbyReadyEvent(players);
+        }
+
+        private TickerLobbyStatusEvent GetStatusMsg(IPlayerSession session)
+        {
+            _playersInLobby.TryGetValue(session, out var status);
+            return new TickerLobbyStatusEvent(RunLevel != GameRunLevel.PreRoundLobby, LobbySong, status == LobbyPlayerStatus.Ready, _roundStartTime, Paused);
+        }
+
+        private void SendStatusToAll()
+        {
+            foreach (var player in _playersInLobby.Keys)
+            {
+                RaiseNetworkEvent(GetStatusMsg(player), player.ConnectedClient);
+            }
+        }
+
+        private TickerLobbyInfoEvent GetInfoMsg()
+        {
+            return new (GetInfoText());
+        }
+
+        private void UpdateLateJoinStatus()
+        {
+            RaiseNetworkEvent(new TickerLateJoinStatusEvent(DisallowLateJoin));
+        }
+
+        public bool PauseStart(bool pause = true)
+        {
+            if (Paused == pause)
+            {
+                return false;
+            }
+
+            Paused = pause;
+
+            if (pause)
+            {
+                _pauseTime = _gameTiming.CurTime;
+            }
+            else if (_pauseTime != default)
+            {
+                _roundStartTime += _gameTiming.CurTime - _pauseTime;
+            }
+
+            RaiseNetworkEvent(new TickerLobbyCountdownEvent(_roundStartTime, Paused));
+
+            _chatManager.DispatchServerAnnouncement(Paused
+                ? "Round start has been paused."
+                : "Round start countdown is now resumed.");
+
+            return true;
+        }
+
+        public bool TogglePause()
+        {
+            PauseStart(!Paused);
+            return Paused;
+        }
+
+        public void ToggleReady(IPlayerSession player, bool ready)
+        {
+            if (!_playersInLobby.ContainsKey(player)) return;
+
+            if (!_prefsManager.HavePreferencesLoaded(player))
+            {
+                return;
+            }
+
+            var status = ready ? LobbyPlayerStatus.Ready : LobbyPlayerStatus.NotReady;
+            _playersInLobby[player] = ready ? LobbyPlayerStatus.Ready : LobbyPlayerStatus.NotReady;
+            RaiseNetworkEvent(GetStatusMsg(player), player.ConnectedClient);
+            RaiseNetworkEvent(GetStatusSingle(player, status));
+        }
+    }
+}