Add HUD button that displays your SSS role and allies (#1895)

* Add button that displays your SSS role and allies

* Capitalize button name

* Add cases for 0, 1 and invalid number of allies

* Make the ally syncing system saner

Content.Client/GameObjects/Components/Suspicion/SuspicionRoleComponent.cs

@@ -0,0 +1,109 @@
+#nullable enable
+using System.Collections.Generic;
+using System.Linq;
+using Content.Client.UserInterface;
+using Content.Client.UserInterface.Suspicion;
+using Content.Shared.GameObjects.Components.Suspicion;
+using Robust.Client.GameObjects;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Interfaces.GameObjects;
+using Robust.Shared.Interfaces.Network;
+using Robust.Shared.IoC;
+using Robust.Shared.Players;
+
+namespace Content.Client.GameObjects.Components.Suspicion
+{
+    [RegisterComponent]
+    public class SuspicionRoleComponent : SharedSuspicionRoleComponent
+    {
+        [Dependency] private readonly IGameHud _gameHud = default!;
+        [Dependency] private readonly IEntityManager _entityManager = default!;
+
+        private SuspicionGui? _gui;
+        private string? _role;
+        private bool? _antagonist;
+
+        public string? Role
+        {
+            get => _role;
+            set
+            {
+                _role = value;
+                _gui?.UpdateLabel();
+                Dirty();
+            }
+        }
+
+        public bool? Antagonist
+        {
+            get => _antagonist;
+            set
+            {
+                _antagonist = value;
+                _gui?.UpdateLabel();
+                Dirty();
+            }
+        }
+
+        public HashSet<IEntity> Allies { get; } = new HashSet<IEntity>();
+
+        public override void HandleComponentState(ComponentState? curState, ComponentState? nextState)
+        {
+            base.HandleComponentState(curState, nextState);
+
+            if (!(curState is SuspicionRoleComponentState state))
+            {
+                return;
+            }
+
+            _role = state.Role;
+            _antagonist = state.Antagonist;
+        }
+
+        public override void HandleMessage(ComponentMessage message, IComponent? component)
+        {
+            base.HandleMessage(message, component);
+
+            switch (message)
+            {
+                case PlayerAttachedMsg _:
+                    if (_gui == null)
+                    {
+                        _gui = new SuspicionGui();
+                    }
+                    else
+                    {
+                        _gui.Parent?.RemoveChild(_gui);
+                    }
+
+                    _gameHud.SuspicionContainer.AddChild(_gui);
+                    _gui.UpdateLabel();
+
+                    break;
+                case PlayerDetachedMsg _:
+                    _gui?.Parent?.RemoveChild(_gui);
+                    break;
+            }
+        }
+
+        public override void HandleNetworkMessage(ComponentMessage message, INetChannel netChannel, ICommonSession? session = null)
+        {
+            base.HandleNetworkMessage(message, netChannel, session);
+
+            switch (message)
+            {
+                case SuspicionAlliesMessage msg:
+                    Allies.Clear();
+                    Allies.UnionWith(msg.Allies.Select(_entityManager.GetEntity));
+                    break;
+            }
+        }
+
+        public override void OnRemove()
+        {
+            base.OnRemove();
+
+            _gui?.Dispose();
+        }
+    }
+}