From 59d5f15bdfd0f8d4890169a08716d3a5799cbd75 Mon Sep 17 00:00:00 2001
From: ragnarok-clanker <ragnarok-clanker>
Date: Fri, 30 Oct 2026 10:19:34 +0000
Subject: [PATCH] Decompile 2 functions in Source/UI/Items/MergeItemWnd.cpp,
 Source/UI/Items/MergeItemWnd.h

Batch #5300 by eAthena: 0 byte-identical, 2 confirmed by peer review.

- fn_09672 CMergeItemWnd::UpdateScroll: logic confirmed by peer review
- fn_09673 CMergeItemWnd::Resize: logic confirmed by peer review

Peer-reviewed-by: meitogi, alisonrag, sherollyner
Accepted without human review: peers confirmed the logic ("same" ahead by at least 3, with 70% of the votes).
---
 Source/UI/Items/MergeItemWnd.cpp | 40 +++++++++++++++++++++++++++++++-
 Source/UI/Items/MergeItemWnd.h   | 11 +++++----
 2 files changed, 46 insertions(+), 5 deletions(-)

diff --git a/Source/UI/Items/MergeItemWnd.cpp b/Source/UI/Items/MergeItemWnd.cpp
index 9bbbf3f6..db3988e9 100644
--- a/Source/UI/Items/MergeItemWnd.cpp
+++ b/Source/UI/Items/MergeItemWnd.cpp
@@ -5,10 +5,10 @@
 #include "Contents/MessageTable.h"
 #include "Network/Connection/Connection.h"
 #include "UI/Buttons/UICheckBox.h"
+#include "UI/Lists/UIScrollBar.h"
 #include "UI/Layout/WindowSnapping.h"
 #include "UI/Window/UIWindowMgr.h"
 #include "Utility/Math/AffineMatrix.h"
-
 #include <cstdlib>
 #include <windows.h>
 
@@ -112,6 +112,44 @@ int CMergeItemWnd::ItemAt(int x, int y) {
   return -1;
 }
 
+// OFFSET: 0x007DFF10
+// FUNCTION: fn_09672
+void CMergeItemWnd::UpdateScroll() {
+  if (this->m_scrollBar == nullptr) {
+    return;
+  }
+
+  const int columns = (this->geometry.width - this->m_marginRight - this->m_gridLeft) / this->m_cellSize;
+  const int rows = this->m_itemCount / columns;
+  const int total = rows > 0 ? rows + 1 : rows;
+  int maximum = total - this->m_rows;
+  if (maximum <= 0) {
+    maximum = 0;
+    this->m_scrollRow = 0;
+  } else if (this->m_scrollRow < 0) {
+    this->m_scrollRow = 0;
+  } else if (this->m_scrollRow > maximum) {
+    this->m_scrollRow = maximum;
+  }
+  this->m_scrollable = maximum;
+  this->m_scrollBar->SetRange(maximum, this->m_rows, total);
+  this->m_scrollBar->SetPosition(this->m_scrollRow);
+  this->m_scrollBar->Invalidate();
+}
+
+// OFFSET: 0x007DFFC0
+// FUNCTION: fn_09673
+void CMergeItemWnd::Resize(int width, int height) {
+  UIWindow::Resize(width, height);
+  this->m_mergeButton->Move(width - 110, height - 25);
+  this->m_cancelButton->Move(width - 60, height - 25);
+  this->m_closeButton->Move(width - 14, 3);
+  this->unknown_00F8->Move(width - 15, height - 15);
+  this->m_scrollBar->Move(width - 15, 17);
+  this->m_scrollBar->Resize(this->m_scrollBar->geometry.width, this->geometry.height - 38);
+  this->UpdateScroll();
+}
+
 // OFFSET: 0x007E0060
 // FUNCTION: fn_09674
 void CMergeItemWnd::FitToGrid(int width, int height) {
diff --git a/Source/UI/Items/MergeItemWnd.h b/Source/UI/Items/MergeItemWnd.h
index 6d2fd868..cc4e0f2b 100644
--- a/Source/UI/Items/MergeItemWnd.h
+++ b/Source/UI/Items/MergeItemWnd.h
@@ -7,10 +7,12 @@
 #include <vector>
 
 class UICheckBox;
+class UIScrollBar;
 
 class CMergeItemWnd : public UIFrameWnd {
 public:
   ~CMergeItemWnd() override;
+  void Resize(int width, int height) override;
   void Slot19() override;
   void Slot25(int x, int y) override;
   void Slot35(int delta) override;
@@ -19,6 +21,7 @@ public:
   __declspec(noinline) int ItemAt(int x, int y);
   void FitToGrid(int width, int height);
   bool RequestMerge();
+  __declspec(noinline) void UpdateScroll();
 
   /* 00B4 */ int m_cellSize;
   /* 00B8 */ int m_gridTop;
@@ -31,12 +34,12 @@ public:
   /* 00D4 */ int unknown_00D4;
   /* 00D8 */ int m_slotRadius;
   /* 00DC */ unsigned int m_minSelection;
-  /* 00E0 */ int unknown_00E0;
-  /* 00E4 */ int unknown_00E4;
-  /* 00E8 */ int unknown_00E8;
+  /* 00E0 */ UIWindow* m_mergeButton;
+  /* 00E4 */ UIWindow* m_cancelButton;
+  /* 00E8 */ UIWindow* m_closeButton;
   /* 00EC */ std::vector<UICheckBox*> m_items;
   /* 00F8 */ UIWindow* unknown_00F8;
-  /* 00FC */ UIWindow* m_scrollBar;
+  /* 00FC */ UIScrollBar* m_scrollBar;
   /* 0100 */ int m_itemCount;
   /* 0104 */ int m_columns;
   /* 0108 */ int m_rows;