From 476651dc33025ea51f5b5ce0e0f4472c544cc170 Mon Sep 17 00:00:00 2001
From: Trident35ro <107998245+Trident35ro@users.noreply.github.com>
Date: Wed, 5 Aug 2026 17:42:58 +0300
Subject: [PATCH] Add: Replacing/updating item actions

Allows modders to handle, modify or replace the actions of items, from eating to attacking, allowing patching vanilla items with new behavior when used.
---
 .../Base/Base.GamePlugin.cs                   | 22 +++++++
 HAModHelper.GamePlugin/Items/Items.Systems.cs | 60 +++++++++++++++++++
 2 files changed, 82 insertions(+)

diff --git a/HAModHelper.GamePlugin/Base/Base.GamePlugin.cs b/HAModHelper.GamePlugin/Base/Base.GamePlugin.cs
index a7e5cfa..d0611de 100644
--- a/HAModHelper.GamePlugin/Base/Base.GamePlugin.cs
+++ b/HAModHelper.GamePlugin/Base/Base.GamePlugin.cs
@@ -282,5 +282,27 @@ public static void Prefix(Connection __instance)
             }
         }
     }
+
+    [HarmonyPatch(typeof(inventory_ctr), "ON_DOUBLE_CLICK")]
+    private static class InventoryDoubleClickPatch
+    {
+        [HarmonyPrefix]
+        static bool Prefix(inventory_ctr __instance, object[] __args)
+        {
+            try
+            {
+                // extract data about the item for logic patching
+                int uiSlotId = (int)__args[0];
+                string action = __args[1]?.ToString() ?? "null";
+
+                return ItemManager.Instance.HandleItemDoubleClick(__instance, uiSlotId, action);
+            }
+            catch (Exception ex)
+            {
+                HAMHMod.Logger.LogError($"[HAMH] Sniffer Patch Fail: {ex.Message}");
+                return true;
+            }
+        }
+    }
 }
 
diff --git a/HAModHelper.GamePlugin/Items/Items.Systems.cs b/HAModHelper.GamePlugin/Items/Items.Systems.cs
index d2762b3..fcfa175 100644
--- a/HAModHelper.GamePlugin/Items/Items.Systems.cs
+++ b/HAModHelper.GamePlugin/Items/Items.Systems.cs
@@ -1,6 +1,7 @@
 using HAModHelper.GamePlugin.Core;
 using HAModHelper.GamePlugin.Helpers;
 using HAModHelper.GamePlugin.Items.Interfaces;
+using System.Reflection;
 
 namespace HAModHelper.GamePlugin.Items.Systems;
 
@@ -133,6 +134,10 @@ public sealed class ItemManager
     private Dictionary<string, Item> _queuedItems = new();
     private HashSet<string> _removedBaseItems = new();
 
+    // these 2 variables are used for intercepting item actions
+    public delegate bool ItemActionHandler(string itemName, string action, int slotId);
+    private List<ItemActionHandler> _interceptors = new();
+
     // TEST-ONLY: Spoof a fake ResourceControl for HAModHelper.Tests to use
     public IResourceControl? DebugResourceControlSource { get; set; }
     private ItemManager() { }
@@ -286,4 +291,59 @@ public Dictionary<string, string> ConvertItem(Item item)
     {
         return ItemConverter.ToGameFields(item);
     }
+
+    public void RegisterInterceptor(ItemActionHandler handler)
+    {
+        _interceptors.Add(handler);
+    }
+
+    public bool HandleItemDoubleClick(object inventoryCtr, int uiSlotId, string action)
+    {
+        int trueSlotId = GetMappedIndex(inventoryCtr, uiSlotId);
+        string itemName = GetItemName(inventoryCtr, trueSlotId);
+
+        bool allowOriginal = true; // this tells the game whether to add the mod's logic on top of the original item logic (true) or to skip the original handling entirely (false)
+
+        foreach (var handler in _interceptors)
+        {
+            if (!handler.Invoke(itemName, action, trueSlotId))
+            {
+                allowOriginal = false;
+            }
+        }
+
+        return allowOriginal;
+    }
+
+
+    // some helpers
+    private string GetItemName(object instance, int trueSlotId)
+    {
+        try
+        {
+            var invProp = instance.GetType().GetProperty("player_inventory");
+            var playerInv = invProp?.GetValue(instance);
+            if (playerInv == null) return "Empty";
+
+            var getItem = playerInv.GetType().GetMethod("get_Item", [typeof(int)]);
+            var itemPair = getItem?.Invoke(playerInv, [trueSlotId]);
+            var item = itemPair?.GetType().GetProperty("item")?.GetValue(itemPair);
+            return item?.GetType().GetProperty("item_name")?.GetValue(item)?.ToString() ?? "Empty";
+        }
+        catch { return "Empty"; }
+    }
+
+    private int GetMappedIndex(object instance, int uiSlotId)
+    {
+        try
+        {
+            var method = instance.GetType().GetMethod("GetTrueInventoryIndex", (System.Reflection.BindingFlags)62);
+            if (method != null) return (int)method.Invoke(instance, [uiSlotId]);
+
+            var field = instance.GetType().GetField("current_page") ?? instance.GetType().GetField("page_index");
+            if (field != null) return ((int)field.GetValue(instance) * 15) + uiSlotId;
+        }
+        catch { }
+        return uiSlotId;
+    }
 }
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