Create alt-tab-delayer.wh.cpp (#993)

* Create alt-tab-delayer.wh.cpp

* Update alt-tab-delayer.wh.cpp

* Update alt-tab-delayer.wh.cpp

* Update alt-tab-delayer.wh.cpp

* Update alt-tab-delayer.wh.cpp

* Update alt-tab-delayer.wh.cpp

* Update alt-tab-delayer.wh.cpp

* Update alt-tab-delayer.wh.cpp

mods/alt-tab-delayer.wh.cpp

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+// ==WindhawkMod==
+// @id              alt-tab-delayer
+// @name            Alt+Tab window delayer
+// @description     Delays the appearance of the Alt+Tab window, preventing flickering and reducing distractions during fast app switching
+// @version         1.0.0
+// @author          L3r0y
+// @github          https://github.com/L3r0yThingz
+// @include         explorer.exe
+// @architecture    x86-64
+// @compilerOptions -lversion
+// ==/WindhawkMod==
+
+// ==WindhawkModReadme==
+/*
+# Alt tab window delayer
+
+This mod improves the Alt+Tab behavior by introducing a short delay before
+displaying the tasks window. It helps reduce visual distractions by preventing
+brief flickers when quickly switching between apps, similar to how macOS and
+Ubuntu handle fast app switching.
+*/
+// ==/WindhawkModReadme==
+
+// ==WindhawkModSettings==
+/*
+- delay: 150
+  $name: Delay
+  $description: The number of milliseconds to delay the switcher.
+*/
+// ==/WindhawkModSettings==
+
+#include <windhawk_utils.h>
+
+enum class WinVersion {
+    Unsupported,
+    Win10,
+    Win11,
+};
+
+WinVersion g_winVersion;
+
+std::atomic<DWORD> g_threadIdForAltTabShowWindow;
+HWND g_taskSwitcherHwnd;
+UINT_PTR g_timerId;
+int g_nCmdShow;
+int g_delayMilliseconds;
+
+VS_FIXEDFILEINFO* GetModuleVersionInfo(HMODULE hModule, UINT* puPtrLen) {
+    void* pFixedFileInfo = nullptr;
+    UINT uPtrLen = 0;
+
+    HRSRC hResource =
+        FindResource(hModule, MAKEINTRESOURCE(VS_VERSION_INFO), RT_VERSION);
+    if (hResource) {
+        HGLOBAL hGlobal = LoadResource(hModule, hResource);
+        if (hGlobal) {
+            void* pData = LockResource(hGlobal);
+            if (pData) {
+                if (!VerQueryValue(pData, L"\\", &pFixedFileInfo, &uPtrLen) ||
+                    uPtrLen == 0) {
+                    pFixedFileInfo = nullptr;
+                    uPtrLen = 0;
+                }
+            }
+        }
+    }
+
+    if (puPtrLen) {
+        *puPtrLen = uPtrLen;
+    }
+
+    return (VS_FIXEDFILEINFO*)pFixedFileInfo;
+}
+
+WinVersion GetWindowsVersion() {
+    VS_FIXEDFILEINFO* fixedFileInfo = GetModuleVersionInfo(nullptr, nullptr);
+    if (!fixedFileInfo) {
+        return WinVersion::Unsupported;
+    }
+
+    WORD major = HIWORD(fixedFileInfo->dwFileVersionMS);
+    WORD minor = LOWORD(fixedFileInfo->dwFileVersionMS);
+    WORD build = HIWORD(fixedFileInfo->dwFileVersionLS);
+    WORD qfe = LOWORD(fixedFileInfo->dwFileVersionLS);
+
+    Wh_Log(L"Version: %u.%u.%u.%u", major, minor, build, qfe);
+
+    switch (major) {
+        case 10:
+            if (build < 22000) {
+                return WinVersion::Win10;
+            } else {
+                return WinVersion::Win11;
+            }
+            break;
+    }
+
+    return WinVersion::Unsupported;
+}
+
+void ClearState() {
+    if (g_timerId != 0) {
+        KillTimer(nullptr, g_timerId);
+        g_timerId = 0;
+    }
+    g_taskSwitcherHwnd = 0;
+}
+
+using XamlAltTabViewHost_DisplayAltTab_t = void(WINAPI*)(void* pThis);
+XamlAltTabViewHost_DisplayAltTab_t XamlAltTabViewHost_DisplayAltTab_Original;
+void WINAPI XamlAltTabViewHost_DisplayAltTab_Hook(void* pThis) {
+    Wh_Log(L">");
+    ClearState();
+    g_threadIdForAltTabShowWindow = GetCurrentThreadId();
+    XamlAltTabViewHost_DisplayAltTab_Original(pThis);
+    g_threadIdForAltTabShowWindow = 0;
+}
+
+using CAltTabViewHost_Show_t = HRESULT(WINAPI*)(void* pThis,
+                                                void* param1,
+                                                void* param2,
+                                                void* param3);
+CAltTabViewHost_Show_t CAltTabViewHost_Show_Original;
+HRESULT WINAPI CAltTabViewHost_Show_Hook(void* pThis,
+                                         void* param1,
+                                         void* param2,
+                                         void* param3) {
+    Wh_Log(L">");
+    ClearState();
+    g_threadIdForAltTabShowWindow = GetCurrentThreadId();
+    HRESULT ret = CAltTabViewHost_Show_Original(pThis, param1, param2, param3);
+    g_threadIdForAltTabShowWindow = 0;
+    return ret;
+}
+
+using ShowWindow_t = decltype(&ShowWindow);
+ShowWindow_t ShowWindow_Original;
+void CALLBACK TimerProc(HWND hWnd, UINT uMsg, UINT_PTR idTimer, DWORD dwTime) {
+    KillTimer(nullptr, g_timerId);
+    g_timerId = 0;
+    Wh_Log(L"Timer proc %d", g_nCmdShow);
+    ShowWindow_Original(g_taskSwitcherHwnd, g_nCmdShow);
+}
+
+BOOL WINAPI ShowWindow_Hook(HWND hWnd, int nCmdShow) {
+    if (hWnd == g_taskSwitcherHwnd && nCmdShow == SW_HIDE) {
+        Wh_Log(L"> Resetting state");
+        ClearState();
+        return ShowWindow_Original(hWnd, nCmdShow);
+    }
+    if (g_threadIdForAltTabShowWindow != GetCurrentThreadId()) {
+        return ShowWindow_Original(hWnd, nCmdShow);
+    }
+
+    Wh_Log(L">");
+    if (nCmdShow != SW_HIDE) {
+        g_taskSwitcherHwnd = hWnd;
+        g_nCmdShow = nCmdShow;
+        g_timerId =
+            SetTimer(nullptr, g_timerId, g_delayMilliseconds, TimerProc);
+        return TRUE;
+    }
+
+    return ShowWindow_Original(hWnd, nCmdShow);
+}
+
+void LoadSettings() {
+    g_delayMilliseconds = Wh_GetIntSetting(L"delay");
+}
+
+BOOL Wh_ModInit() {
+    Wh_Log(L">");
+
+    g_winVersion = GetWindowsVersion();
+
+    LoadSettings();
+
+    HMODULE twinuiPcshellModule = LoadLibrary(L"twinui.pcshell.dll");
+    if (!twinuiPcshellModule) {
+        Wh_Log(L"Couldn't load twinui.pcshell.dll");
+        return FALSE;
+    }
+
+    if (g_winVersion == WinVersion::Win11) {
+        // twinui.pcshell.dll
+        WindhawkUtils::SYMBOL_HOOK twinuiPcshellSymbolHooks[] = {
+            {
+                {LR"(private: void __cdecl XamlAltTabViewHost::DisplayAltTab(void))"},
+                &XamlAltTabViewHost_DisplayAltTab_Original,
+                XamlAltTabViewHost_DisplayAltTab_Hook,
+            },
+
+        };
+
+        if (!HookSymbols(twinuiPcshellModule, twinuiPcshellSymbolHooks,
+                         ARRAYSIZE(twinuiPcshellSymbolHooks))) {
+            return FALSE;
+        }
+    } else if (g_winVersion == WinVersion::Win10) {
+        // twinui.pcshell.dll
+        WindhawkUtils::SYMBOL_HOOK twinuiPcshellSymbolHooks[] = {
+            {
+                {LR"(public: virtual long __cdecl CAltTabViewHost::Show(struct IImmersiveMonitor *,enum ALT_TAB_VIEW_FLAGS,struct IApplicationView *))"},
+                &CAltTabViewHost_Show_Original,
+                CAltTabViewHost_Show_Hook,
+            },
+
+        };
+
+        if (!HookSymbols(twinuiPcshellModule, twinuiPcshellSymbolHooks,
+                         ARRAYSIZE(twinuiPcshellSymbolHooks))) {
+            return FALSE;
+        }
+    } else {
+        Wh_Log(L"Unsupported Windows version");
+        return FALSE;
+    }
+
+    WindhawkUtils::Wh_SetFunctionHookT(ShowWindow, ShowWindow_Hook,
+                                       &ShowWindow_Original);
+
+    return TRUE;
+}
+
+void Wh_ModSettingsChanged() {
+    LoadSettings();
+}