From a9f6b3dadbf116ecf54ec3af6a2279d406f2df3e Mon Sep 17 00:00:00 2001
From: Amrsatrio <satrionareswara@yahoo.com>
Date: Wed, 11 Dec 2024 05:06:30 +0700
Subject: [PATCH] Taskbar10: Better TaskbarSd handling. (#4020) - Invisible
 mode (2) now supports ep_taskbar. We do this by completely overriding
 WM_PAINT and WM_PRINTCLIENT when this mode is active, instead of null-ing the
 HTHEME. - Disabled mode (1) now hides the window instead of returning 0
 (width/height value depending on taskbar orientation) in message 0x464
 (calculate minimum size). Fortunately CTrayNotify handles the visibility of
 the button, therefore this also fixes tab navigation when the button is
 hidden.

---
 ExplorerPatcher/dllmain.c | 91 ++++++++++++++++++++++++++++-----------
 1 file changed, 65 insertions(+), 26 deletions(-)

diff --git a/ExplorerPatcher/dllmain.c b/ExplorerPatcher/dllmain.c
index 779a87962..46ce50632 100644
--- a/ExplorerPatcher/dllmain.c
+++ b/ExplorerPatcher/dllmain.c
@@ -5047,6 +5047,23 @@ __declspec(dllexport) BOOL explorer_SetChildWindowNoActivateHook(HWND hWnd)
 
 #pragma region "Hide Show desktop button"
 #if WITH_MAIN_PATCHER
+DWORD GetTaskbarSd()
+{
+    DWORD dwVal = 1, dwSize = sizeof(DWORD);
+    if (SHRegGetValueFromHKCUHKLMFunc && SHRegGetValueFromHKCUHKLMFunc(
+        TEXT("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced"),
+        TEXT("TaskbarSd"),
+        SRRF_RT_REG_DWORD,
+        NULL,
+        &dwVal,
+        &dwSize
+    ) == ERROR_SUCCESS)
+    {
+        return dwVal;
+    }
+    return 1; // Visible
+}
+
 INT64 ShowDesktopSubclassProc(
     _In_ HWND   hWnd,
     _In_ UINT   uMsg,
@@ -5056,31 +5073,60 @@ INT64 ShowDesktopSubclassProc(
     DWORD_PTR   dwRefData
 )
 {
-    if (uMsg == WM_NCDESTROY)
-    {
-        RemoveWindowSubclass(hWnd, ShowDesktopSubclassProc, ShowDesktopSubclassProc);
-    }
-    else if (uMsg == WM_USER + 100)
+    switch (uMsg)
     {
-        LRESULT lRes = DefSubclassProc(hWnd, uMsg, wParam, lParam);
-        if (lRes > 0)
+        case WM_NCDESTROY:
         {
-            DWORD dwVal = 0, dwSize = sizeof(DWORD);
-            if (SHRegGetValueFromHKCUHKLMFunc && SHRegGetValueFromHKCUHKLMFunc(
-                TEXT("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced"),
-                TEXT("TaskbarSd"),
-                SRRF_RT_REG_DWORD,
-                NULL,
-                &dwVal,
-                (LPDWORD)(&dwSize)
-            ) == ERROR_SUCCESS && !dwVal)
+            RemoveWindowSubclass(hWnd, ShowDesktopSubclassProc, ShowDesktopSubclassProc);
+            break;
+        }
+        case WM_PAINT:
+        case WM_PRINTCLIENT:
+        {
+            HANDLE h_dwTaskbarSd = GetPropW(hWnd, L"EP_TaskbarSd");
+            if (h_dwTaskbarSd)
             {
-                lRes = 0;
+                DWORD dwTaskbarSd = (DWORD)h_dwTaskbarSd - 1;
+                if (dwTaskbarSd == 2) // Invisible
+                {
+                    PAINTSTRUCT ps;
+                    HDC hdc = BeginPaint(hWnd, &ps);
+                    if (hdc)
+                    {
+                        HDC hdcPaint;
+                        HPAINTBUFFER hBufferedPaint = BeginBufferedPaint(hdc, &ps.rcPaint, BPBF_TOPDOWNDIB, NULL, &hdcPaint);
+                        if (hBufferedPaint)
+                        {
+                            if (IsThemeActive())
+                            {
+                                DrawThemeParentBackground(hWnd, hdcPaint, NULL);
+                            }
+                            else
+                            {
+                                RECT rc;
+                                GetClientRect(hWnd, &rc);
+                                FillRect(hdc, &rc, (HBRUSH)(COLOR_BTNFACE + 1));
+                            }
+                            EndBufferedPaint(hBufferedPaint, TRUE);
+                        }
+                        EndPaint(hWnd, &ps);
+                    }
+                    return 0;
+                }
             }
-            else if (dwVal) PostMessageW(hWnd, 794, 0, 0);
+            break;
+        }
+        case WM_THEMECHANGED:
+        case WM_SETTINGCHANGE:
+        {
+            LRESULT lRes = DefSubclassProc(hWnd, uMsg, wParam, lParam);
+            DWORD dwTaskbarSd = GetTaskbarSd();
+            SetPropW(hWnd, L"EP_TaskbarSd", (HANDLE)(dwTaskbarSd + 1));
+            ShowWindow(hWnd, dwTaskbarSd != 0 ? SW_SHOW : SW_HIDE);
+            return lRes;
         }
-        return lRes;
     }
+
     return DefSubclassProc(hWnd, uMsg, wParam, lParam);
 }
 #endif
@@ -7295,13 +7341,6 @@ HTHEME explorer_OpenThemeDataForDpi(
         }
         return hTheme;
     }
-    else if ((*((WORD*)&(pszClassList)+1)) && !wcscmp(pszClassList, L"TaskbarShowDesktop"))
-    {
-        DWORD dwVal = 0, dwSize = sizeof(DWORD);
-        RegGetValueW(HKEY_CURRENT_USER, L"Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced", L"TaskbarSD", RRF_RT_REG_DWORD, NULL, &dwVal, &dwSize);
-        if (dwVal == 2) return NULL;
-        return OpenThemeDataForDpi(hwnd, pszClassList, dpi);
-    }
 
     // task list - Taskband2 from CTaskListWnd::_HandleThemeChanged
     if (bClassicThemeMitigations && (*((WORD*)&(pszClassList)+1)) && !wcscmp(pszClassList, L"Taskband2"))