Proto-kinetic crusher (#16277)

Co-authored-by: AJCM-git <60196617+AJCM-git@users.noreply.github.com>

Content.Server/PowerCell/PowerCellSystem.Draw.cs

@@ -0,0 +1,91 @@
+using Content.Server.Power.Components;
+using Content.Shared.PowerCell;
+using Content.Shared.PowerCell.Components;
+
+namespace Content.Server.PowerCell;
+
+public sealed partial class PowerCellSystem
+{
+    /*
+     * Handles PowerCellDraw
+     */
+
+    private static readonly TimeSpan Delay = TimeSpan.FromSeconds(1);
+
+    public override void Update(float frameTime)
+    {
+        base.Update(frameTime);
+        var query = EntityQueryEnumerator<PowerCellDrawComponent, PowerCellSlotComponent>();
+
+        while (query.MoveNext(out var uid, out var comp, out var slot))
+        {
+            if (!comp.Drawing)
+                continue;
+
+            if (_timing.CurTime < comp.NextUpdateTime)
+                continue;
+
+            comp.NextUpdateTime += Delay;
+
+            if (!TryGetBatteryFromSlot(uid, out var batteryEnt, out var battery, slot))
+                continue;
+
+            if (_battery.TryUseCharge(batteryEnt.Value, comp.DrawRate, battery))
+                continue;
+
+            comp.Drawing = false;
+            var ev = new PowerCellSlotEmptyEvent();
+            RaiseLocalEvent(uid, ref ev);
+        }
+    }
+
+    private void OnUnpaused(EntityUid uid, PowerCellDrawComponent component, ref EntityUnpausedEvent args)
+    {
+        component.NextUpdateTime += args.PausedTime;
+    }
+
+    private void OnDrawChargeChanged(EntityUid uid, PowerCellDrawComponent component, ref ChargeChangedEvent args)
+    {
+        // Update the bools for client prediction.
+        bool canDraw;
+        bool canUse;
+
+        if (component.UseRate > 0f)
+        {
+            canUse = args.Charge > component.UseRate;
+        }
+        else
+        {
+            canUse = true;
+        }
+
+        if (component.DrawRate > 0f)
+        {
+            canDraw = args.Charge > 0f;
+        }
+        else
+        {
+            canDraw = true;
+        }
+
+        if (canUse != component.CanUse || canDraw != component.CanDraw)
+        {
+            component.CanDraw = canDraw;
+            component.CanUse = canUse;
+            Dirty(component);
+        }
+    }
+
+    private void OnDrawCellChanged(EntityUid uid, PowerCellDrawComponent component, PowerCellChangedEvent args)
+    {
+        var canDraw = !args.Ejected && HasCharge(uid, float.MinValue);
+        var canUse = !args.Ejected && HasActivatableCharge(uid, component);
+
+        if (canUse != component.CanUse || canDraw != component.CanDraw)
+        {
+            component.CanDraw = canDraw;
+            component.CanUse = canUse;
+            Dirty(component);
+        }
+    }
+}