Rejigging Item slots (#4933)

* itemslot overhaul

* remove "shared" prefix

* handle component shutdown

* comments, cleanup, tests

* comments and minor tweak

* rename ItemSlotManagerState

* fix swapping

* fix merge

* Add ItemSlot verb text override

* fix merge  (IEntity -> entityUid)

* Fix merge (LabelSystem)

* Fix merge (nuke disk)

* fix test

Content.Shared/Containers/ItemSlot/ItemSlotsComponent.cs

@@ -0,0 +1,124 @@
+using Content.Shared.Sound;
+using Content.Shared.Whitelist;
+using Robust.Shared.Analyzers;
+using Robust.Shared.Containers;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Prototypes;
+using Robust.Shared.Serialization;
+using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype;
+using Robust.Shared.ViewVariables;
+using System;
+using System.Collections.Generic;
+
+namespace Content.Shared.Containers.ItemSlots
+{
+    /// <summary>
+    ///     Used for entities that can hold items in different slots. Needed by ItemSlotSystem to support basic
+    ///     insert/eject interactions.
+    /// </summary>
+    [RegisterComponent]
+    [Friend(typeof(ItemSlotsSystem))]
+    public class ItemSlotsComponent : Component
+    {
+        public override string Name => "ItemSlots";
+
+        [ViewVariables]
+        [DataField("slots")]
+        public Dictionary<string, ItemSlot> Slots = new();
+    }
+
+    [Serializable, NetSerializable]
+    public sealed class ItemSlotsComponentState : ComponentState
+    {
+        public readonly Dictionary<string, bool> SlotLocked;
+
+        public ItemSlotsComponentState(Dictionary<string, ItemSlot> slots)
+        {
+            SlotLocked = new(slots.Count);
+
+            foreach (var (key, slot) in slots)
+            {
+                SlotLocked[key] = slot.Locked;
+            }
+        }
+    }
+
+    /// <summary>
+    ///     This is effectively a wrapper for a ContainerSlot that adds content functionality like entity whitelists and
+    ///     insert/eject sounds.
+    /// </summary>
+    [DataDefinition]
+    [Friend(typeof(ItemSlotsSystem))]
+    public class ItemSlot
+    {
+        [DataField("whitelist")]
+        public EntityWhitelist? Whitelist;
+
+        [DataField("insertSound")]
+        public SoundSpecifier? InsertSound;
+        // maybe default to /Audio/Weapons/Guns/MagIn/batrifle_magin.ogg ??
+
+        [DataField("ejectSound")]
+        public SoundSpecifier? EjectSound;
+        // maybe default to /Audio/Machines/id_swipe.ogg?
+
+        /// <summary>
+        ///     The name of this item slot. This will be shown to the user in the verb menu.
+        /// </summary>
+        /// <remarks>
+        ///     This will be passed through Loc.GetString. If the name is an empty string, then verbs will use the name
+        ///     of the currently held or currently inserted entity instead.
+        /// </remarks>
+        [DataField("name")]
+        public string Name = string.Empty;
+
+        [DataField("startingItem", customTypeSerializer: typeof(PrototypeIdSerializer<EntityPrototype>))]
+        public string? StartingItem;
+
+        /// <summary>
+        ///     Whether or not an item can currently be ejected or inserted from this slot.
+        /// </summary>
+        /// <remarks>
+        ///     This doesn't have to mean the slot is somehow physically locked. In the case of the item cabinet, the
+        ///     cabinet may simply be closed at the moment and needs to be opened first.
+        /// </remarks>
+        [DataField("locked")]
+        [ViewVariables(VVAccess.ReadWrite)]
+        public bool Locked = false;
+
+        /// <summary>
+        ///     Whether the item slots system will attempt to eject this item to the user's hands when interacted with.
+        /// </summary>
+        /// <remarks>
+        ///     For most item slots, this is probably not the case (eject is usually an alt-click interaction). But
+        ///     there are some exceptions. For example item cabinets and charging stations should probably eject their
+        ///     contents when clicked on normally.
+        /// </remarks>
+        [DataField("ejectOnInteract")]
+        public bool EjectOnInteract = false;
+
+        /// <summary>
+        ///     Override the insert verb text. Defaults to [insert category] -> [item-name]. If not null, the verb will
+        ///     not be given a category.
+        /// </summary>
+        [DataField("insertVerbText")]
+        public string? InsertVerbText;
+
+        /// <summary>
+        ///     Override the insert verb text. Defaults to [eject category] -> [item-name]. If not null, the verb will
+        ///     not be given a category.
+        /// </summary>
+        [DataField("ejectVerbText")]
+        public string? EjectVerbText;
+
+        [ViewVariables]
+        public ContainerSlot ContainerSlot = default!;
+
+        public string ID => ContainerSlot.ID;
+
+        // Convenience properties
+        public bool HasItem => ContainerSlot.ContainedEntity != null;
+        public IEntity? Item => ContainerSlot.ContainedEntity;
+    }
+}