Hunger and thirst HUDs (#18066)

* security HUD now shows a job icon on entities with a body

* thirst goggles

* set starting hud gear

Content.Client/Overlays/ComponentAddedOverlaySystemBase.cs

@@ -0,0 +1,115 @@
+using Content.Shared.Clothing.Components;
+using Content.Shared.GameTicking;
+using Content.Shared.Inventory;
+using Content.Shared.Inventory.Events;
+using Robust.Client.GameObjects;
+using Robust.Client.Player;
+
+namespace Content.Client.Overlays
+{
+    public abstract class ComponentAddedOverlaySystemBase<T> : EntitySystem where T : IComponent
+    {
+        [Dependency] private readonly IPlayerManager _player = default!;
+        [Dependency] private readonly IEntityManager _entityManager = default!;
+        private InventorySystem _invSystem = default!;
+
+        protected bool IsActive = false;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            SubscribeLocalEvent<T, ComponentInit>(OnInit);
+            SubscribeLocalEvent<T, ComponentRemove>(OnRemove);
+
+            SubscribeLocalEvent<PlayerAttachedEvent>(OnPlayerAttached);
+            SubscribeLocalEvent<PlayerDetachedEvent>(OnPlayerDetached);
+
+            SubscribeLocalEvent<T, GotEquippedEvent>(OnCompEquip);
+            SubscribeLocalEvent<T, GotUnequippedEvent>(OnCompUnequip);
+
+            SubscribeLocalEvent<RoundRestartCleanupEvent>(OnRoundRestart);
+
+            _invSystem = _entityManager.System<InventorySystem>();
+        }
+
+        public void ApplyOverlay(T component)
+        {
+            IsActive = true;
+            OnApplyOverlay(component);
+        }
+
+        public void RemoveOverlay()
+        {
+            IsActive = false;
+            OnRemoveOverlay();
+        }
+
+        protected virtual void OnApplyOverlay(T component) { }
+
+        protected virtual void OnRemoveOverlay() { }
+
+        private void OnInit(EntityUid uid, T component, ComponentInit args)
+        {
+            if (_player.LocalPlayer?.ControlledEntity == uid)
+            {
+                ApplyOverlay(component);
+            }
+        }
+
+        private void OnRemove(EntityUid uid, T component, ComponentRemove args)
+        {
+            if (_player.LocalPlayer?.ControlledEntity == uid)
+            {
+                RemoveOverlay();
+            }
+        }
+
+        private void OnPlayerAttached(PlayerAttachedEvent args)
+        {
+            if (TryComp<T>(args.Entity, out var component))
+                ApplyOverlay(component);
+
+            if (TryComp(args.Entity, out InventoryComponent? inventoryComponent)
+                && _invSystem.TryGetSlots(args.Entity, out var slotDefinitions, inventoryComponent))
+            {
+                foreach (var slot in slotDefinitions)
+                {
+                    if (_invSystem.TryGetSlotEntity(args.Entity, slot.Name, out var itemUid)
+                        && TryComp(itemUid.Value, out component))
+                    {
+                        OnCompEquip(itemUid.Value, component, new GotEquippedEvent(args.Entity, itemUid.Value, slot));
+                    }
+                }
+            }
+        }
+
+        private void OnPlayerDetached(PlayerDetachedEvent args)
+        {
+            RemoveOverlay();
+        }
+
+        private void OnCompEquip(EntityUid uid, T component, GotEquippedEvent args)
+        {
+            if (!TryComp<ClothingComponent>(uid, out var clothing)) return;
+
+            if (args.Equipee != _player.LocalPlayer?.ControlledEntity) return;
+
+            if (!clothing.Slots.HasFlag(args.SlotFlags)) return;
+
+            ApplyOverlay(component);
+        }
+
+        private void OnCompUnequip(EntityUid uid, T component, GotUnequippedEvent args)
+        {
+            if (args.Equipee != _player.LocalPlayer?.ControlledEntity) return;
+
+            RemoveOverlay();
+        }
+
+        private void OnRoundRestart(RoundRestartCleanupEvent args)
+        {
+            RemoveOverlay();
+        }
+    }
+}