From fc2f525052f2afa5b1dcbe949ce722cd1092008c Mon Sep 17 00:00:00 2001
From: ph <patrickmheintz@gmail.com>
Date: Sun, 14 Jun 2026 11:55:37 -0700
Subject: [PATCH] fix halfmilk RBA (#6670)

---
 .../Restorations/BottleAdventure.cpp             | 16 ++++++++++++++++
 .../vanilla-behavior/GIVanillaBehavior.h         | 10 ++++++++++
 soh/src/code/z_parameter.c                       |  7 +++++--
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/soh/soh/Enhancements/Restorations/BottleAdventure.cpp b/soh/soh/Enhancements/Restorations/BottleAdventure.cpp
index 22cc74e679..ef4a8d4e8a 100644
--- a/soh/soh/Enhancements/Restorations/BottleAdventure.cpp
+++ b/soh/soh/Enhancements/Restorations/BottleAdventure.cpp
@@ -452,6 +452,11 @@ void DoRBA(uint8_t itemToPutInBottle) {
     }
 }
 
+bool DoHalfMilkRBA(uint8_t item) {
+    auto itemOnCRight = gSaveContext.equips.buttonItems[3];
+    return (item == ITEM_BOTTLE) && (gSaveContext.inventory.items[itemOnCRight] == ITEM_MILK_BOTTLE);
+}
+
 void RegisterBottleAdventure() {
     REGISTER_VB_SHOULD(VB_SET_BUTTON_ITEM_FROM_C_BUTTON_SLOT, {
         // if we aren't dealing with the b button, early return
@@ -476,6 +481,17 @@ void RegisterBottleAdventure() {
         auto itemToPutInBottle = static_cast<uint8_t>(va_arg(args, int32_t));
         DoRBA(itemToPutInBottle);
     });
+
+    REGISTER_VB_SHOULD(VB_EMPTY_BOTTLE_TO_HALF_MILK, {
+        // if we aren't dealing with a bottle on b, early return
+        auto buttonBottleIsOn = static_cast<uint8_t>(va_arg(args, int32_t));
+        if (buttonBottleIsOn != 0) {
+            return;
+        }
+
+        auto item = static_cast<uint8_t>(va_arg(args, int32_t));
+        *should = DoHalfMilkRBA(item);
+    });
 }
 
 static RegisterShipInitFunc initFunc(RegisterBottleAdventure);
diff --git a/soh/soh/Enhancements/game-interactor/vanilla-behavior/GIVanillaBehavior.h b/soh/soh/Enhancements/game-interactor/vanilla-behavior/GIVanillaBehavior.h
index 1b64f2b4d7..c252a62599 100644
--- a/soh/soh/Enhancements/game-interactor/vanilla-behavior/GIVanillaBehavior.h
+++ b/soh/soh/Enhancements/game-interactor/vanilla-behavior/GIVanillaBehavior.h
@@ -620,6 +620,16 @@ typedef enum {
     // - Player*
     VB_EMPTYING_BOTTLE,
 
+    // #### `result`
+    // ```c
+    // (gSaveContext.inventory.items[gSaveContext.equips.cButtonSlots[button - 1]] == ITEM_MILK_BOTTLE) &&
+    //     (item == ITEM_BOTTLE)
+    // ```
+    // #### `args`
+    // - `int32_t` (button - promoted from `u8`)
+    // - `int32_t` (item - promoted from `u8`)
+    VB_EMPTY_BOTTLE_TO_HALF_MILK,
+
     // #### `result`
     // ```c
     // (Message_GetState(&play->msgCtx) == TEXT_STATE_EVENT) && Message_ShouldAdvance(play)
diff --git a/soh/src/code/z_parameter.c b/soh/src/code/z_parameter.c
index e96929a109..c378d15f48 100644
--- a/soh/src/code/z_parameter.c
+++ b/soh/src/code/z_parameter.c
@@ -2671,8 +2671,11 @@ void Inventory_UpdateBottleItem(PlayState* play, u8 item, u8 button) {
                  gSaveContext.inventory.items[gSaveContext.equips.cButtonSlots[button - 1]]);
 
     // Special case to only empty half of a Lon Lon Milk Bottle
-    if ((gSaveContext.inventory.items[gSaveContext.equips.cButtonSlots[button - 1]] == ITEM_MILK_BOTTLE) &&
-        (item == ITEM_BOTTLE)) {
+    if (GameInteractor_Should(
+            VB_EMPTY_BOTTLE_TO_HALF_MILK,
+            (gSaveContext.inventory.items[gSaveContext.equips.cButtonSlots[button - 1]] == ITEM_MILK_BOTTLE) &&
+                (item == ITEM_BOTTLE),
+            button, item)) {
         item = ITEM_MILK_HALF;
     }