Flashlights now run off a power cell. (#121)

* Flashlight runs off a power cell now.

* Cleanup

Content.Server/GameObjects/Components/Interactable/HandheldLightComponent.cs

@@ -1,14 +1,10 @@
 using Content.Server.GameObjects.EntitySystems;
+using Content.Server.GameObjects.Components.Power;
 using SS14.Server.GameObjects;
+using SS14.Server.GameObjects.Components.Container;
 using SS14.Shared.Enums;
-using SS14.Shared.GameObjects;
 using SS14.Shared.Interfaces.GameObjects;
-using SS14.Shared.Serialization;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
+using SS14.Shared.GameObjects;
 using SS14.Shared.ViewVariables;
 
 namespace Content.Server.GameObjects.Components.Interactable
@@ -16,10 +12,25 @@ namespace Content.Server.GameObjects.Components.Interactable
     /// <summary>
     /// Component that represents a handheld lightsource which can be toggled on and off.
     /// </summary>
-    class HandheldLightComponent : Component, EntitySystems.IUse, EntitySystems.IExamine
+    class HandheldLightComponent : Component, IUse, IExamine
     {
-        PointLightComponent pointLight;
-        SpriteComponent spriteComponent;
+        private PointLightComponent _pointLight;
+        private SpriteComponent _spriteComponent;
+        [ViewVariables] private ContainerSlot _cellContainer;
+
+        private PowerCellComponent Cell
+        {
+            get
+            {
+                if (_cellContainer.ContainedEntity == null)
+                {
+                    return null;
+                }
+
+                _cellContainer.ContainedEntity.TryGetComponent(out PowerCellComponent cell);
+                return cell;
+            }
+        }
 
         public override string Name => "HandheldLight";
 
@@ -29,12 +40,22 @@ namespace Content.Server.GameObjects.Components.Interactable
         [ViewVariables]
         public bool Activated { get; private set; } = false;
 
+        public const float Wattage = 10;
+
         public override void Initialize()
         {
             base.Initialize();
 
-            pointLight = Owner.GetComponent<PointLightComponent>();
-            spriteComponent = Owner.GetComponent<SpriteComponent>();
+            _pointLight = Owner.GetComponent<PointLightComponent>();
+            _spriteComponent = Owner.GetComponent<SpriteComponent>();
+            _cellContainer =
+                ContainerManagerComponent.Ensure<ContainerSlot>("flashlight_cell_container", Owner, out var existed);
+
+            if (!existed)
+            {
+                var cell = Owner.EntityManager.SpawnEntity("PowerCellSmallHyper");
+                _cellContainer.Insert(cell);
+            }
         }
 
         bool IUse.UseEntity(IEntity user)
@@ -54,19 +75,56 @@ namespace Content.Server.GameObjects.Components.Interactable
             // Update sprite and light states to match the activation.
             if (Activated)
             {
-                spriteComponent.LayerSetState(0, "lantern_on");
-                pointLight.State = LightState.On;
+                _spriteComponent.LayerSetState(0, "lantern_on");
+                _pointLight.State = LightState.On;
             }
             else
             {
-                spriteComponent.LayerSetState(0, "lantern_off");
-                pointLight.State = LightState.Off;
+                _spriteComponent.LayerSetState(0, "lantern_off");
+                _pointLight.State = LightState.Off;
             }
 
             // Toggle always succeeds.
             return true;
         }
 
+        public void TurnOff()
+        {
+            if (!Activated)
+            {
+                return;
+            }
+
+            _spriteComponent.LayerSetState(0, "lantern_off");
+            _pointLight.State = LightState.Off;
+            Activated = false;
+        }
+
+        public void TurnOn()
+        {
+            if (Activated)
+            {
+                return;
+            }
+
+            var cell = Cell;
+            if (cell == null)
+            {
+                return;
+            }
+
+            // To prevent having to worry about frame time in here.
+            // Let's just say you need a whole second of charge before you can turn it on.
+            // Simple enough.
+            if (cell.AvailableCharge(1) < Wattage)
+            {
+                return;
+            }
+
+            _spriteComponent.LayerSetState(0, "lantern_on");
+            _pointLight.State = LightState.On;
+        }
+
         string IExamine.Examine()
         {
             if (Activated)
@@ -76,5 +134,19 @@ namespace Content.Server.GameObjects.Components.Interactable
 
             return null;
         }
+
+        public void OnUpdate(float frameTime)
+        {
+            if (!Activated)
+            {
+                return;
+            }
+
+            var cell = Cell;
+            if (cell == null || !cell.TryDeductWattage(Wattage, frameTime))
+            {
+                TurnOff();
+            }
+        }
     }
 }