Health analyzer displays turns off when the battery dies (#16125)

Content.Server/Power/EntitySystems/BatterySystem.cs

@@ -11,6 +11,7 @@ namespace Content.Server.Power.EntitySystems
     [UsedImplicitly]
     public sealed class BatterySystem : EntitySystem
     {
+        [Dependency] private readonly SharedAppearanceSystem _sharedAppearanceSystem = default!;
         public override void Initialize()
         {
             base.Initialize();

Content.Server/PowerCell/PowerCellSystem.cs

@@ -166,7 +166,6 @@ public sealed class PowerCellSystem : SharedPowerCellSystem
 
         return HasCharge(uid, battery.UseRate, cell, user);
     }
-
     /// <summary>
     /// Tries to use the <see cref="PowerCellDrawComponent.UseRate"/> for this entity.
     /// </summary>
@@ -179,6 +178,7 @@ public sealed class PowerCellSystem : SharedPowerCellSystem
 
         if (TryUseCharge(uid, battery.UseRate, cell, user))
         {
+            _sharedAppearanceSystem.SetData(uid, PowerCellSlotVisuals.Enabled, HasActivatableCharge(uid, battery, cell, user));
             _activatable.CheckUsage(uid);
             return true;
         }
@@ -243,6 +243,7 @@ public sealed class PowerCellSystem : SharedPowerCellSystem
             return false;
         }
 
+        _sharedAppearanceSystem.SetData(uid, PowerCellSlotVisuals.Enabled, battery.Charge > 0);
         return true;
     }
 

Content.Shared/PowerCell/Components/PowerCellComponent.cs

@@ -24,3 +24,8 @@ public enum PowerCellVisuals : byte
 {
     ChargeLevel
 }
+[Serializable, NetSerializable]
+public enum PowerCellSlotVisuals : byte
+{
+    Enabled
+}

Content.Shared/PowerCell/SharedPowerCellSystem.cs

@@ -8,6 +8,7 @@ namespace Content.Shared.PowerCell;
 public abstract class SharedPowerCellSystem : EntitySystem
 {
     [Dependency] private readonly ItemSlotsSystem _itemSlots = default!;
+    [Dependency] private readonly SharedAppearanceSystem _appearance = default!;
 
     public override void Initialize()
     {
@@ -48,7 +49,7 @@ public abstract class SharedPowerCellSystem : EntitySystem
 
         if (args.Container.ID != component.CellSlotId)
             return;
-
+        _appearance.SetData(uid, PowerCellSlotVisuals.Enabled, true);
         RaiseLocalEvent(uid, new PowerCellChangedEvent(false), false);
     }
 
@@ -56,7 +57,7 @@ public abstract class SharedPowerCellSystem : EntitySystem
     {
         if (args.Container.ID != component.CellSlotId)
             return;
-
+        _appearance.SetData(uid, PowerCellSlotVisuals.Enabled, false);
         RaiseLocalEvent(uid, new PowerCellChangedEvent(true), false);
     }
 }

Resources/Prototypes/Entities/Objects/Specific/Medical/healthanalyzer.yml

@@ -9,7 +9,13 @@
   - type: Sprite
     sprite: Objects/Specific/Medical/healthanalyzer.rsi
     netsync: false
-    state: analyzer
+    state: icon
+    layers:
+    - state: icon
+    - state: analyzer
+      shader: unshaded
+      visible: true
+      map: [ "enum.PowerDeviceVisualLayers.Powered" ]
   - type: PowerCellDraw
     drawRate: 0
     useRate: 20
@@ -27,6 +33,13 @@
   - type: Tag
     tags:
     - DiscreteHealthAnalyzer
+  - type: Appearance
+  - type: GenericVisualizer
+    visuals:
+      enum.PowerCellSlotVisuals.Enabled:
+        enum.PowerDeviceVisualLayers.Powered:
+          True: { visible: true }
+          False: { visible: false }
 
 - type: entity
   id: HandheldHealthAnalyzerEmpty