Targeted item actions (action/heal), item.add scenario action, inventory cell Decorate; mod cover

src/ITargetedItemAction.cs

@@ -0,0 +1,23 @@
+using Cthangover.Core.Items;
+using Cthangover.Core.Settings;
+
+namespace Cthangover.Mods.Items
+{
+    /// <summary>
+    /// Item action that needs to know whom it is applied to. The core
+    /// <see cref="IItemAction"/> contract has no target, so an effect on a party
+    /// member (healing) could not tell which member was picked in
+    /// <see cref="Cthangover.Core.UI.Inventory.CharacterTargetPanel"/>. Items with
+    /// <see cref="ItemType.TargetUsed"/> whose action implements this interface get
+    /// <see cref="UseOn"/> with the chosen character; other actions keep receiving
+    /// the plain <see cref="IItemAction.UseAction"/>.
+    /// </summary>
+    public interface ITargetedItemAction : IItemAction
+    {
+        /// <summary>
+        /// Applies the item to <paramref name="target"/>. Returns <c>false</c> when
+        /// nothing happened (e.g. healing at full health), so the item is not spent.
+        /// </summary>
+        bool UseOn(IItem item, CharacterInfoData target);
+    }
+}