add special creature ability as item type

src/module/actor/actor-data.ts

@@ -1,21 +1,10 @@
+import { ModifiableData, ResourceData, UsableResource } from "../common/common-data";
+import { DS4 } from "../config";
+
+export type ActorType = keyof typeof DS4.actorTypes;
+
 export type DS4ActorDataType = DS4ActorDataCharacter | DS4ActorDataCreature;
 
-export interface ModifiableData<T> {
-    base: T;
-    mod: T;
-    total?: T;
-}
-
-interface ResourceData<T> extends ModifiableData<T> {
-    value: T;
-    max?: T;
-}
-
-interface UsableResource<T> {
-    total: T;
-    used: T;
-}
-
 interface DS4ActorDataBase {
     attributes: DS4ActorDataAttributes;
     traits: DS4ActorDataTraits;

src/module/actor/actor-sheet.ts

@@ -1,4 +1,5 @@
-import { DS4ItemDataType } from "../item/item-data";
+import { DS4Item } from "../item/item";
+import { DS4ItemDataType, ItemType } from "../item/item-data";
 import { DS4Actor } from "./actor";
 import { DS4ActorDataType } from "./actor-data";
 
@@ -207,4 +208,26 @@ export class DS4ActorSheet extends ActorSheet<DS4ActorDataType, DS4Actor, DS4Ite
             });
         }
     }
+
+    /**
+     * @override
+     */
+    async _onDrop(event: DragEvent): Promise<boolean | unknown> {
+        const data = JSON.parse(event.dataTransfer?.getData("text/plain")) as { type?: string };
+        if (data.type === "Item") {
+            const item = await Item.fromDropData(data as Parameters<typeof DS4Item.fromDropData>[0]);
+            if (item && !this.actor.canOwnItemType(item.data.type as ItemType)) {
+                ui.notifications.warn(
+                    game.i18n.format("DS4.WarningActorCannotOwnItem", {
+                        actorName: this.actor.name,
+                        actorType: this.actor.data.type,
+                        itemName: item.name,
+                        itemType: item.data.type,
+                    }),
+                );
+                return false;
+            }
+        }
+        super._onDrop(event);
+    }
 }

src/module/actor/actor.ts

@@ -1,6 +1,7 @@
+import { ModifiableData } from "../common/common-data";
 import { DS4Item } from "../item/item";
-import { DS4ItemDataType } from "../item/item-data";
-import { DS4ActorDataType, ModifiableData } from "./actor-data";
+import { DS4ItemDataType, ItemType } from "../item/item-data";
+import { DS4ActorDataType } from "./actor-data";
 
 export class DS4Actor extends Actor<DS4ActorDataType, DS4ItemDataType, DS4Item> {
     /** @override */
@@ -21,4 +22,37 @@ export class DS4Actor extends Actor<DS4ActorDataType, DS4ItemDataType, DS4Item>
 
         combatValues.hitPoints.max = combatValues.hitPoints.total;
     }
+
+    /**
+     * The list of item types that can be owned by this actor.
+     */
+    get ownableItemTypes(): Array<ItemType> {
+        switch (this.data.type) {
+            case "character":
+                return [
+                    "weapon",
+                    "armor",
+                    "shield",
+                    "spell",
+                    "trinket",
+                    "equipment",
+                    "talent",
+                    "racialAbility",
+                    "language",
+                    "alphabet",
+                ];
+            case "creature":
+                return ["weapon", "armor", "spell", "specialCreatureAbility"];
+            default:
+                [];
+        }
+    }
+
+    /**
+     * Checks whether or not the given item type can be owned by the actor.
+     * @param itemType the item type to check
+     */
+    canOwnItemType(itemType: ItemType): boolean {
+        return this.ownableItemTypes.includes(itemType);
+    }
 }