Remove FoodContainer, add whitelists, replace with SpawnItemsOnUse (#4358)

Content.Server/Storage/EntitySystems/StorageSystem.cs

@@ -0,0 +1,96 @@
+using System.Collections.Generic;
+using Content.Server.Interaction;
+using Content.Server.Storage.Components;
+using JetBrains.Annotations;
+using Robust.Server.Player;
+using Robust.Shared.Containers;
+using Robust.Shared.GameObjects;
+
+namespace Content.Server.Storage.EntitySystems
+{
+    [UsedImplicitly]
+    internal sealed class StorageSystem : EntitySystem
+    {
+        private readonly List<IPlayerSession> _sessionCache = new();
+
+        /// <inheritdoc />
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            SubscribeLocalEvent<EntRemovedFromContainerMessage>(HandleEntityRemovedFromContainer);
+            SubscribeLocalEvent<EntInsertedIntoContainerMessage>(HandleEntityInsertedIntoContainer);
+        }
+
+        /// <inheritdoc />
+        public override void Update(float frameTime)
+        {
+            foreach (var component in ComponentManager.EntityQuery<ServerStorageComponent>(true))
+            {
+                CheckSubscribedEntities(component);
+            }
+        }
+
+        private static void HandleEntityRemovedFromContainer(EntRemovedFromContainerMessage message)
+        {
+            var oldParentEntity = message.Container.Owner;
+
+            if (oldParentEntity.TryGetComponent(out ServerStorageComponent? storageComp))
+            {
+                storageComp.HandleEntityMaybeRemoved(message);
+            }
+
+            if (oldParentEntity.TryGetComponent<StorageCounterComponent>(out var newStorageComp))
+            {
+                newStorageComp.ContainerUpdateAppearance(message.Container);
+            }
+        }
+
+        private static void HandleEntityInsertedIntoContainer(EntInsertedIntoContainerMessage message)
+        {
+            var oldParentEntity = message.Container.Owner;
+
+            if (oldParentEntity.TryGetComponent(out ServerStorageComponent? storageComp))
+            {
+                storageComp.HandleEntityMaybeInserted(message);
+            }
+
+            if (oldParentEntity.TryGetComponent<StorageCounterComponent>(out var newStorageComp))
+            {
+                newStorageComp.ContainerUpdateAppearance(message.Container);
+            }
+        }
+
+        private void CheckSubscribedEntities(ServerStorageComponent storageComp)
+        {
+
+            // We have to cache the set of sessions because Unsubscribe modifies the original.
+            _sessionCache.Clear();
+            _sessionCache.AddRange(storageComp.SubscribedSessions);
+
+            if (_sessionCache.Count == 0)
+                return;
+
+            var storagePos = storageComp.Owner.Transform.WorldPosition;
+            var storageMap = storageComp.Owner.Transform.MapID;
+
+            foreach (var session in _sessionCache)
+            {
+                var attachedEntity = session.AttachedEntity;
+
+                // The component manages the set of sessions, so this invalid session should be removed soon.
+                if (attachedEntity == null || !attachedEntity.IsValid())
+                    continue;
+
+                if (storageMap != attachedEntity.Transform.MapID)
+                    continue;
+
+                var distanceSquared = (storagePos - attachedEntity.Transform.WorldPosition).LengthSquared;
+                if (distanceSquared > InteractionSystem.InteractionRangeSquared)
+                {
+                    storageComp.UnsubscribeSession(session);
+                }
+            }
+        }
+    }
+}