SpawnOnBatteryFull component (#43727)

* code stuff

* fix error

* now its fixed

* use the charge from the arg

* only on battery full

* remove whitespace

Co-authored-by: slarticodefast <161409025+slarticodefast@users.noreply.github.com>

* use default! instead of null!

Co-authored-by: slarticodefast <161409025+slarticodefast@users.noreply.github.com>

* use set charge

---------

Co-authored-by: slarticodefast <161409025+slarticodefast@users.noreply.github.com>

Content.Server/Power/Components/SpawnOnBatteryFullComponent.cs

@@ -0,0 +1,25 @@
+using Content.Shared.EntityTable.EntitySelectors;
+using Robust.Shared.Prototypes;
+
+namespace Content.Server.Power.Components;
+
+/// <summary>
+/// Spawns a entity when the battery reaches max charge.
+/// It also consumes all power when spawning the entity.
+/// </summary>
+[RegisterComponent]
+public sealed partial class SpawnOnBatteryFullComponent : Component
+{
+    /// <summary>
+    /// A entity proto to spawn.
+    /// </summary>
+    /// <remarks>Takes priority over <see cref="Table"/></remarks>
+    [DataField]
+    public EntProtoId? Proto;
+
+    /// <summary>
+    /// A entity table to spawn stuff from.
+    /// </summary>
+    [DataField]
+    public EntityTableSelector? Table;
+}

Content.Server/Power/EntitySystems/SpawnOnBatteryFullSystem.cs

@@ -0,0 +1,48 @@
+using Content.Server.Power.Components;
+using Content.Shared.EntityTable;
+using Content.Shared.EntityTable.EntitySelectors;
+using Content.Shared.Power;
+using Content.Shared.Power.Components;
+using Robust.Shared.Prototypes;
+
+namespace Content.Server.Power.EntitySystems;
+
+public sealed class SpawnOnBatteryFullSystem : EntitySystem
+{
+    [Dependency] private readonly BatterySystem _battery = default!;
+    [Dependency] private readonly EntityTableSystem _entityTable = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<SpawnOnBatteryFullComponent, BatteryStateChangedEvent>(OnBatteryStateChange);
+    }
+
+    private void OnBatteryStateChange(Entity<SpawnOnBatteryFullComponent> entity, ref BatteryStateChangedEvent args)
+    {
+        if (args.NewState != BatteryState.Full)
+            return;
+
+        if (entity.Comp.Proto == null)
+            SpawnFromEntityTable(entity, entity.Comp.Table);
+        else
+            SpawnFromProto(entity, entity.Comp.Proto.Value);
+
+        _battery.SetCharge(entity.Owner, 0);
+    }
+
+    private void SpawnFromEntityTable(EntityUid entity, EntityTableSelector? table)
+    {
+        var spawns = _entityTable.GetSpawns(table);
+        foreach (var spawn in spawns)
+        {
+            Spawn(spawn, Transform(entity).Coordinates);
+        }
+    }
+
+    private void SpawnFromProto(EntityUid entity, EntProtoId proto)
+    {
+        Spawn(proto, Transform(entity).Coordinates);
+    }
+}