Knowledge UI (#779)

* knowledge button in HUD

* ui controller

* bugfixes

* finish

* all-knowing ghosts

* Create knowledge-ui.ftl

Content.Client/_CP14/Knowledge/ClientCP14KnowledgeSystem.cs

@@ -1,7 +1,42 @@
 using Content.Shared._CP14.Knowledge;
+using Content.Shared._CP14.Knowledge.Prototypes;
+using Robust.Client.Player;
+using Robust.Shared.Prototypes;
 
 namespace Content.Client._CP14.Knowledge;
 
 public sealed partial class ClientCP14KnowledgeSystem : SharedCP14KnowledgeSystem
 {
+    [Dependency] private readonly IPlayerManager _players = default!;
+
+    public event Action<KnowledgeData>? OnKnowledgeUpdate;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeNetworkEvent<CP14KnowledgeInfoEvent>(OnCharacterKnowledgeEvent);
+    }
+
+    public void RequestKnowledgeInfo()
+    {
+        var entity = _players.LocalEntity;
+        if (entity is null)
+            return;
+
+        RaiseNetworkEvent(new RequestKnowledgeInfoEvent(GetNetEntity(entity.Value)));
+    }
+
+    private void OnCharacterKnowledgeEvent(CP14KnowledgeInfoEvent msg, EntitySessionEventArgs args)
+    {
+        var entity = GetEntity(msg.NetEntity);
+        var data = new KnowledgeData(entity, msg.AllKnowledge);
+
+        OnKnowledgeUpdate?.Invoke(data);
+    }
+
+    public readonly record struct KnowledgeData(
+        EntityUid Entity,
+        HashSet<ProtoId<CP14KnowledgePrototype>> AllKnowledges
+    );
 }