ECS BatteryComponent (#15337)

Content.Server/Power/EntitySystems/BatterySystem.cs

@@ -4,6 +4,7 @@ using Content.Server.Power.Components;
 using Content.Shared.Examine;
 using Content.Shared.Rejuvenate;
 using JetBrains.Annotations;
+using Robust.Shared.Utility;
 
 namespace Content.Server.Power.EntitySystems
 {
@@ -61,8 +62,9 @@ namespace Content.Server.Power.EntitySystems
             var enumerator = AllEntityQuery<PowerNetworkBatteryComponent, BatteryComponent>();
             while (enumerator.MoveNext(out var netBat, out var bat))
             {
+                DebugTools.Assert(bat.Charge <= bat.MaxCharge && bat.Charge >= 0);
                 netBat.NetworkBattery.Capacity = bat.MaxCharge;
-                netBat.NetworkBattery.CurrentStorage = bat.CurrentCharge;
+                netBat.NetworkBattery.CurrentStorage = bat.Charge;
             }
         }
 
@@ -73,10 +75,17 @@ namespace Content.Server.Power.EntitySystems
             while (enumerator.MoveNext(out var uid, out var netBat, out var bat))
             {
                 var netCharge = netBat.NetworkBattery.CurrentStorage;
+
+                bat.Charge = netCharge;
+                DebugTools.Assert(bat.Charge <= bat.MaxCharge && bat.Charge >= 0);
+
+                // TODO maybe decrease tolerance & track the charge at the time the event was most recently raised.
+                // Ensures that events aren't skipped when there are many tiny power changes.
                 if (MathHelper.CloseTo(bat.CurrentCharge, netCharge))
                     continue;
 
-                bat.CurrentCharge = netCharge;
+                var changeEv = new ChargeChangedEvent(netCharge, bat.MaxCharge);
+                RaiseLocalEvent(uid, ref changeEv);
             }
         }
 
@@ -101,7 +110,61 @@ namespace Content.Server.Power.EntitySystems
         private void OnEmpPulse(EntityUid uid, BatteryComponent component, ref EmpPulseEvent args)
         {
             args.Affected = true;
-            component.UseCharge(args.EnergyConsumption);
+            UseCharge(uid, args.EnergyConsumption, component);
+        }
+
+        public float UseCharge(EntityUid uid, float value, BatteryComponent? battery = null)
+        {
+            if (value <= 0 ||  !Resolve(uid, ref battery) || battery.CurrentCharge == 0)
+                return 0;
+
+            var newValue = Math.Clamp(0, battery.CurrentCharge - value, battery._maxCharge);
+            var delta = newValue - battery.Charge;
+            battery.Charge = newValue;
+            var ev = new ChargeChangedEvent(battery.CurrentCharge, battery._maxCharge);
+            RaiseLocalEvent(uid, ref ev);
+            return delta;
+        }
+
+        public void SetMaxCharge(EntityUid uid, float value, BatteryComponent? battery = null)
+        {
+            if (!Resolve(uid, ref battery))
+                return;
+
+            var old = battery._maxCharge;
+            battery._maxCharge = Math.Max(value, 0);
+            battery.Charge = Math.Min(battery.Charge, battery._maxCharge);
+            if (MathHelper.CloseTo(battery._maxCharge, old))
+                return;
+
+            var ev = new ChargeChangedEvent(battery.CurrentCharge, battery._maxCharge);
+            RaiseLocalEvent(uid, ref ev);
+        }
+
+        public void SetCharge(EntityUid uid, float value, BatteryComponent? battery = null)
+        {
+            if (!Resolve(uid, ref battery))
+                return;
+
+            var old = battery.Charge;
+            battery.Charge = MathHelper.Clamp(value, 0, battery._maxCharge);
+            if (MathHelper.CloseTo(battery.Charge, old))
+                return;
+
+            var ev = new ChargeChangedEvent(battery.CurrentCharge, battery._maxCharge);
+            RaiseLocalEvent(uid, ref ev);
+        }
+
+        /// <summary>
+        ///     If sufficient charge is available on the battery, use it. Otherwise, don't.
+        /// </summary>
+        public bool TryUseCharge(EntityUid uid, float value, BatteryComponent? battery = null)
+        {
+            if (!Resolve(uid, ref battery, false) || value > battery.Charge)
+                return false;
+
+            UseCharge(uid, value, battery);
+            return true;
         }
     }
 }