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.GamePreset.cs

@@ -0,0 +1,98 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+using System.Reflection;
+using Content.Server.GameTicking.Presets;
+using Content.Shared.CCVar;
+using Content.Shared.Preferences;
+using Robust.Shared.Network;
+using Robust.Shared.ViewVariables;
+using Robust.Shared.IoC;
+
+namespace Content.Server.GameTicking
+{
+    public partial class GameTicker
+    {
+        public const float PresetFailedCooldownIncrease = 30f;
+
+        [ViewVariables] private Type? _presetType;
+
+        [ViewVariables]
+        public GamePreset? Preset
+        {
+            get => _preset ?? MakeGamePreset(new Dictionary<NetUserId, HumanoidCharacterProfile>());
+            set => _preset = value;
+        }
+
+        public ImmutableDictionary<string, Type> Presets { get; private set; } = default!;
+
+        private GamePreset? _preset;
+
+        private void InitializeGamePreset()
+        {
+            var presets = new Dictionary<string, Type>();
+
+            foreach (var type in _reflectionManager.FindTypesWithAttribute<GamePresetAttribute>())
+            {
+                var attribute = type.GetCustomAttribute<GamePresetAttribute>();
+
+                presets.Add(attribute!.Id.ToLowerInvariant(), type);
+
+                foreach (var alias in attribute.Aliases)
+                {
+                    presets.Add(alias.ToLowerInvariant(), type);
+                }
+            }
+
+            Presets = presets.ToImmutableDictionary();
+
+            SetStartPreset(_configurationManager.GetCVar(CCVars.GameLobbyDefaultPreset));
+        }
+
+        public bool OnGhostAttempt(Mind.Mind mind, bool canReturnGlobal)
+        {
+            return Preset?.OnGhostAttempt(mind, canReturnGlobal) ?? false;
+        }
+
+        public bool TryGetPreset(string name, [NotNullWhen(true)] out Type? type)
+        {
+            name = name.ToLowerInvariant();
+            return Presets.TryGetValue(name, out type);
+        }
+
+        public void SetStartPreset(Type type, bool force = false)
+        {
+            // Do nothing if this game ticker is a dummy!
+            if (DummyTicker)
+                return;
+
+            if (!typeof(GamePreset).IsAssignableFrom(type)) throw new ArgumentException("type must inherit GamePreset");
+
+            _presetType = type;
+            UpdateInfoText();
+
+            if (force)
+            {
+                StartRound(true);
+            }
+        }
+
+        public void SetStartPreset(string name, bool force = false)
+        {
+            if (!TryGetPreset(name, out var type))
+            {
+                throw new NotSupportedException($"No preset found with name {name}");
+            }
+
+            SetStartPreset(type, force);
+        }
+
+        private GamePreset MakeGamePreset(Dictionary<NetUserId, HumanoidCharacterProfile> readyProfiles)
+        {
+            var preset = _dynamicTypeFactory.CreateInstance<GamePreset>(_presetType ?? typeof(PresetSandbox));
+            preset.ReadyProfiles = readyProfiles;
+            return preset;
+        }
+    }
+}