nsWindow.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sts=2 sw=2 et cin: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * nsWindow - Native window management and event handling.
 *
 * nsWindow is organized into a set of major blocks and
 * block subsections. The layout is as follows:
 *
 *  Includes
 *  Variables
 *  nsIWidget impl.
 *     nsIWidget methods and utilities
 *  nsSwitchToUIThread impl.
 *     nsSwitchToUIThread methods and utilities
 *  Moz events
 *     Event initialization
 *     Event dispatching
 *  Native events
 *     Wndproc(s)
 *     Event processing
 *     OnEvent event handlers
 *  IME management and accessibility
 *  Transparency
 *  Popup hook handling
 *  Misc. utilities
 *  Child window impl.
 *
 * Search for "BLOCK:" to find major blocks.
 * Search for "SECTION:" to find specific sections.
 *
 * Blocks should be split out into separate files if they
 * become unmanageable.
 *
 * Related source:
 *
 *  nsWindowDefs.h     - Definitions, macros, structs, enums
 *                       and general setup.
 *  nsWindowDbg.h/.cpp - Debug related code and directives.
 *  nsWindowGfx.h/.cpp - Graphics and painting.
 *
 */

/**************************************************************
 **************************************************************
 **
 ** BLOCK: Includes
 **
 ** Include headers.
 **
 **************************************************************
 **************************************************************/

#include "gfx2DGlue.h"
#include "gfxEnv.h"
#include "gfxPlatform.h"

#include "mozilla/AutoRestore.h"
#include "mozilla/Logging.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/MiscEvents.h"
#include "mozilla/MouseEvents.h"
#include "mozilla/TouchEvents.h"

#include "mozilla/ipc/MessageChannel.h"
#include <algorithm>
#include <limits>

#include "nsWindow.h"
#include "nsAppRunner.h"

#include <shellapi.h>
#include <windows.h>
#include <wtsapi32.h>
#include <process.h>
#include <commctrl.h>
#include <dbt.h>
#include <unknwn.h>
#include <psapi.h>

#include "mozilla/Logging.h"
#include "prtime.h"
#include "prenv.h"

#include "mozilla/WidgetTraceEvent.h"
#include "nsIAppShell.h"
#include "nsISupportsPrimitives.h"
#include "nsIKeyEventInPluginCallback.h"
#include "nsITheme.h"
#include "nsIObserverService.h"
#include "nsIScreenManager.h"
#include "imgIContainer.h"
#include "nsIFile.h"
#include "nsIRollupListener.h"
#include "nsIServiceManager.h"
#include "nsIClipboard.h"
#include "WinMouseScrollHandler.h"
#include "nsFontMetrics.h"
#include "nsIFontEnumerator.h"
#include "nsFont.h"
#include "nsRect.h"
#include "nsThreadUtils.h"
#include "nsNativeCharsetUtils.h"
#include "nsGkAtoms.h"
#include "nsCRT.h"
#include "nsAppDirectoryServiceDefs.h"
#include "nsWidgetsCID.h"
#include "nsTHashtable.h"
#include "nsHashKeys.h"
#include "nsString.h"
#include "mozilla/Services.h"
#include "nsNativeThemeWin.h"
#include "nsWindowsDllInterceptor.h"
#include "nsLayoutUtils.h"
#include "nsView.h"
#include "nsIWindowMediator.h"
#include "nsIServiceManager.h"
#include "nsWindowGfx.h"
#include "gfxWindowsPlatform.h"
#include "gfxDWriteFonts.h"
#include "Layers.h"
#include "nsPrintfCString.h"
#include "mozilla/Preferences.h"
#include "nsISound.h"
#include "SystemTimeConverter.h"
#include "WinTaskbar.h"
#include "WidgetUtils.h"
#include "nsIWidgetListener.h"
#include "mozilla/dom/MouseEventBinding.h"
#include "mozilla/dom/Touch.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/GPUProcessManager.h"
#include "nsIAppStartup.h"
#include "mozilla/WindowsVersion.h"
#include "mozilla/TextEvents.h"  // For WidgetKeyboardEvent
#include "mozilla/TextEventDispatcherListener.h"
#include "mozilla/widget/nsAutoRollup.h"
#include "mozilla/widget/WinNativeEventData.h"
#include "mozilla/widget/PlatformWidgetTypes.h"
#include "nsStyleConsts.h"
#include "nsBidiKeyboard.h"
#include "nsStyleConsts.h"
#include "gfxConfig.h"
#include "InProcessWinCompositorWidget.h"
#include "InputDeviceUtils.h"
#include "ScreenHelperWin.h"
#include "mozilla/StaticPrefs_layout.h"

#include "nsIGfxInfo.h"
#include "nsUXThemeConstants.h"
#include "KeyboardLayout.h"
#include "nsNativeDragTarget.h"
#include <mmsystem.h>  // needed for WIN32_LEAN_AND_MEAN
#include <zmouse.h>
#include <richedit.h>

#if defined(ACCESSIBILITY)

#  ifdef DEBUG
#    include "mozilla/a11y/Logging.h"
#  endif

#  include "oleidl.h"
#  include <winuser.h>
#  include "nsAccessibilityService.h"
#  include "mozilla/PresShell.h"
#  include "mozilla/a11y/DocAccessible.h"
#  include "mozilla/a11y/LazyInstantiator.h"
#  include "mozilla/a11y/Platform.h"
#  if !defined(WINABLEAPI)
#    include <winable.h>
#  endif  // !defined(WINABLEAPI)
#endif    // defined(ACCESSIBILITY)

#include "nsIWinTaskbar.h"
#define NS_TASKBAR_CONTRACTID "@mozilla.org/windows-taskbar;1"

#include "nsIWindowsUIUtils.h"

#include "nsWindowDefs.h"

#include "nsCrashOnException.h"
#include "nsIXULRuntime.h"

#include "nsIContent.h"

#include "mozilla/BackgroundHangMonitor.h"
#include "WinIMEHandler.h"

#include "npapi.h"

#include <d3d11.h>

#include "InkCollector.h"

// ERROR from wingdi.h (below) gets undefined by some code.
// #define ERROR               0
// #define RGN_ERROR ERROR
#define ERROR 0

#if !defined(SM_CONVERTIBLESLATEMODE)
#  define SM_CONVERTIBLESLATEMODE 0x2003
#endif

#if !defined(WM_DPICHANGED)
#  define WM_DPICHANGED 0x02E0
#endif

#include "mozilla/gfx/DeviceManagerDx.h"
#include "mozilla/layers/InputAPZContext.h"
#include "mozilla/layers/KnowsCompositor.h"
#include "InputData.h"

#include "mozilla/Telemetry.h"
#include "mozilla/plugins/PluginProcessParent.h"
#include "mozilla/webrender/WebRenderAPI.h"

using namespace mozilla;
using namespace mozilla::dom;
using namespace mozilla::gfx;
using namespace mozilla::layers;
using namespace mozilla::widget;
using namespace mozilla::plugins;

/**************************************************************
 **************************************************************
 **
 ** BLOCK: Variables
 **
 ** nsWindow Class static initializations and global variables.
 **
 **************************************************************
 **************************************************************/

/**************************************************************
 *
 * SECTION: nsWindow statics
 *
 **************************************************************/

bool nsWindow::sDropShadowEnabled = true;
uint32_t nsWindow::sInstanceCount = 0;
bool nsWindow::sSwitchKeyboardLayout = false;
BOOL nsWindow::sIsOleInitialized = FALSE;
HCURSOR nsWindow::sHCursor = nullptr;
imgIContainer* nsWindow::sCursorImgContainer = nullptr;
nsWindow* nsWindow::sCurrentWindow = nullptr;
bool nsWindow::sJustGotDeactivate = false;
bool nsWindow::sJustGotActivate = false;
bool nsWindow::sIsInMouseCapture = false;

// imported in nsWidgetFactory.cpp
TriStateBool nsWindow::sCanQuit = TRI_UNKNOWN;

// Hook Data Memebers for Dropdowns. sProcessHook Tells the
// hook methods whether they should be processing the hook
// messages.
HHOOK nsWindow::sMsgFilterHook = nullptr;
HHOOK nsWindow::sCallProcHook = nullptr;
HHOOK nsWindow::sCallMouseHook = nullptr;
bool nsWindow::sProcessHook = false;
UINT nsWindow::sRollupMsgId = 0;
HWND nsWindow::sRollupMsgWnd = nullptr;
UINT nsWindow::sHookTimerId = 0;

// Mouse Clicks - static variable definitions for figuring
// out 1 - 3 Clicks.
POINT nsWindow::sLastMousePoint = {0};
POINT nsWindow::sLastMouseMovePoint = {0};
LONG nsWindow::sLastMouseDownTime = 0L;
LONG nsWindow::sLastClickCount = 0L;
BYTE nsWindow::sLastMouseButton = 0;

bool nsWindow::sHaveInitializedPrefs = false;

TriStateBool nsWindow::sHasBogusPopupsDropShadowOnMultiMonitor = TRI_UNKNOWN;

static SystemTimeConverter<DWORD>& TimeConverter() {
  static SystemTimeConverter<DWORD> timeConverterSingleton;
  return timeConverterSingleton;
}

namespace mozilla {

class CurrentWindowsTimeGetter {
 public:
  explicit CurrentWindowsTimeGetter(HWND aWnd) : mWnd(aWnd) {}

  DWORD GetCurrentTime() const { return ::GetTickCount(); }

  void GetTimeAsyncForPossibleBackwardsSkew(const TimeStamp& aNow) {
    DWORD currentTime = GetCurrentTime();
    if (sBackwardsSkewStamp && currentTime == sLastPostTime) {
      // There's already one inflight with this timestamp. Don't
      // send a duplicate.
      return;
    }
    sBackwardsSkewStamp = Some(aNow);
    sLastPostTime = currentTime;
    static_assert(sizeof(WPARAM) >= sizeof(DWORD),
                  "Can't fit a DWORD in a WPARAM");
    ::PostMessage(mWnd, MOZ_WM_SKEWFIX, sLastPostTime, 0);
  }

  static bool GetAndClearBackwardsSkewStamp(DWORD aPostTime,
                                            TimeStamp* aOutSkewStamp) {
    if (aPostTime != sLastPostTime) {
      // The SKEWFIX message is stale; we've sent a new one since then.
      // Ignore this one.
      return false;
    }
    MOZ_ASSERT(sBackwardsSkewStamp);
    *aOutSkewStamp = sBackwardsSkewStamp.value();
    sBackwardsSkewStamp = Nothing();
    return true;
  }

 private:
  static Maybe<TimeStamp> sBackwardsSkewStamp;
  static DWORD sLastPostTime;
  HWND mWnd;
};

Maybe<TimeStamp> CurrentWindowsTimeGetter::sBackwardsSkewStamp;
DWORD CurrentWindowsTimeGetter::sLastPostTime = 0;

}  // namespace mozilla

/**************************************************************
 *
 * SECTION: globals variables
 *
 **************************************************************/

static const char* sScreenManagerContractID =
    "@mozilla.org/gfx/screenmanager;1";

extern mozilla::LazyLogModule gWindowsLog;

// Global used in Show window enumerations.
static bool gWindowsVisible = false;

// True if we have sent a notification that we are suspending/sleeping.
static bool gIsSleepMode = false;

static NS_DEFINE_CID(kCClipboardCID, NS_CLIPBOARD_CID);

// General purpose user32.dll hook object
static WindowsDllInterceptor sUser32Intercept;

// 2 pixel offset for eTransparencyBorderlessGlass which equals the size of
// the default window border Windows paints. Glass will be extended inward
// this distance to remove the border.
static const int32_t kGlassMarginAdjustment = 2;

// When the client area is extended out into the default window frame area,
// this is the minimum amount of space along the edge of resizable windows
// we will always display a resize cursor in, regardless of the underlying
// content.
static const int32_t kResizableBorderMinSize = 3;

// We should never really try to accelerate windows bigger than this. In some
// cases this might lead to no D3D9 acceleration where we could have had it
// but D3D9 does not reliably report when it supports bigger windows. 8192
// is as safe as we can get, we know at least D3D10 hardware always supports
// this, other hardware we expect to report correctly in D3D9.
#define MAX_ACCELERATED_DIMENSION 8192

// On window open (as well as after), Windows has an unfortunate habit of
// sending rather a lot of WM_NCHITTEST messages. Because we have to do point
// to DOM target conversions for these, we cache responses for a given
// coordinate this many milliseconds:
#define HITTEST_CACHE_LIFETIME_MS 50

#if defined(ACCESSIBILITY)

namespace mozilla {

/**
 * Windows touchscreen code works by setting a global WH_GETMESSAGE hook and
 * injecting tiptsf.dll. The touchscreen process then posts registered messages
 * to our main thread. The tiptsf hook picks up those registered messages and
 * uses them as commands, some of which call into UIA, which then calls into
 * MSAA, which then sends WM_GETOBJECT to us.
 *
 * We can get ahead of this by installing our own thread-local WH_GETMESSAGE
 * hook. Since thread-local hooks are called ahead of global hooks, we will
 * see these registered messages before tiptsf does. At this point we can then
 * raise a flag that blocks a11y before invoking CallNextHookEx which will then
 * invoke the global tiptsf hook. Then when we see WM_GETOBJECT, we check the
 * flag by calling TIPMessageHandler::IsA11yBlocked().
 *
 * For Windows 8, we also hook tiptsf!ProcessCaretEvents, which is an a11y hook
 * function that also calls into UIA.
 */
class TIPMessageHandler {
 public:
  ~TIPMessageHandler() {
    if (mHook) {
      ::UnhookWindowsHookEx(mHook);
    }
  }

  static void Initialize() {
    if (!IsWin8OrLater()) {
      return;
    }

    if (sInstance) {
      return;
    }

    sInstance = new TIPMessageHandler();
    ClearOnShutdown(&sInstance);
  }

  static bool IsA11yBlocked() {
    if (!sInstance) {
      return false;
    }

    return sInstance->mA11yBlockCount > 0;
  }

 private:
  TIPMessageHandler() : mHook(nullptr), mA11yBlockCount(0) {
    MOZ_ASSERT(NS_IsMainThread());

    // Registered messages used by tiptsf
    mMessages[0] = ::RegisterWindowMessage(L"ImmersiveFocusNotification");
    mMessages[1] = ::RegisterWindowMessage(L"TipCloseMenus");
    mMessages[2] = ::RegisterWindowMessage(L"TabletInputPanelOpening");
    mMessages[3] = ::RegisterWindowMessage(L"IHM Pen or Touch Event noticed");
    mMessages[4] = ::RegisterWindowMessage(L"ProgrammabilityCaretVisibility");
    mMessages[5] = ::RegisterWindowMessage(L"CaretTrackingUpdateIPHidden");
    mMessages[6] = ::RegisterWindowMessage(L"CaretTrackingUpdateIPInfo");

    mHook = ::SetWindowsHookEx(WH_GETMESSAGE, &TIPHook, nullptr,
                               ::GetCurrentThreadId());
    MOZ_ASSERT(mHook);

    // On touchscreen devices, tiptsf.dll will have been loaded when STA COM was
    // first initialized.
    if (!IsWin10OrLater() && GetModuleHandle(L"tiptsf.dll") &&
        !sProcessCaretEventsStub) {
      sTipTsfInterceptor.Init("tiptsf.dll");
      DebugOnly<bool> ok = sProcessCaretEventsStub.Set(
          sTipTsfInterceptor, "ProcessCaretEvents", &ProcessCaretEventsHook);
      MOZ_ASSERT(ok);
    }

    if (!sSendMessageTimeoutWStub) {
      sUser32Intercept.Init("user32.dll");
      DebugOnly<bool> hooked = sSendMessageTimeoutWStub.Set(
          sUser32Intercept, "SendMessageTimeoutW", &SendMessageTimeoutWHook);
      MOZ_ASSERT(hooked);
    }
  }

  class MOZ_RAII A11yInstantiationBlocker {
   public:
    A11yInstantiationBlocker() {
      if (!TIPMessageHandler::sInstance) {
        return;
      }
      ++TIPMessageHandler::sInstance->mA11yBlockCount;
    }

    ~A11yInstantiationBlocker() {
      if (!TIPMessageHandler::sInstance) {
        return;
      }
      MOZ_ASSERT(TIPMessageHandler::sInstance->mA11yBlockCount > 0);
      --TIPMessageHandler::sInstance->mA11yBlockCount;
    }
  };

  friend class A11yInstantiationBlocker;

  static LRESULT CALLBACK TIPHook(int aCode, WPARAM aWParam, LPARAM aLParam) {
    if (aCode < 0 || !sInstance) {
      return ::CallNextHookEx(nullptr, aCode, aWParam, aLParam);
    }

    MSG* msg = reinterpret_cast<MSG*>(aLParam);
    UINT& msgCode = msg->message;

    for (uint32_t i = 0; i < ArrayLength(sInstance->mMessages); ++i) {
      if (msgCode == sInstance->mMessages[i]) {
        A11yInstantiationBlocker block;
        return ::CallNextHookEx(nullptr, aCode, aWParam, aLParam);
      }
    }

    return ::CallNextHookEx(nullptr, aCode, aWParam, aLParam);
  }

  static void CALLBACK ProcessCaretEventsHook(HWINEVENTHOOK aWinEventHook,
                                              DWORD aEvent, HWND aHwnd,
                                              LONG aObjectId, LONG aChildId,
                                              DWORD aGeneratingTid,
                                              DWORD aEventTime) {
    A11yInstantiationBlocker block;
    sProcessCaretEventsStub(aWinEventHook, aEvent, aHwnd, aObjectId, aChildId,
                            aGeneratingTid, aEventTime);
  }

  static LRESULT WINAPI SendMessageTimeoutWHook(HWND aHwnd, UINT aMsgCode,
                                                WPARAM aWParam, LPARAM aLParam,
                                                UINT aFlags, UINT aTimeout,
                                                PDWORD_PTR aMsgResult) {
    // We don't want to handle this unless the message is a WM_GETOBJECT that we
    // want to block, and the aHwnd is a nsWindow that belongs to the current
    // thread.
    if (!aMsgResult || aMsgCode != WM_GETOBJECT ||
        static_cast<DWORD>(aLParam) != OBJID_CLIENT ||
        !WinUtils::GetNSWindowPtr(aHwnd) ||
        ::GetWindowThreadProcessId(aHwnd, nullptr) != ::GetCurrentThreadId() ||
        !IsA11yBlocked()) {
      return sSendMessageTimeoutWStub(aHwnd, aMsgCode, aWParam, aLParam, aFlags,
                                      aTimeout, aMsgResult);
    }

    // In this case we want to fake the result that would happen if we had
    // decided not to handle WM_GETOBJECT in our WndProc. We hand the message
    // off to DefWindowProc to accomplish this.
    *aMsgResult = static_cast<DWORD_PTR>(
        ::DefWindowProcW(aHwnd, aMsgCode, aWParam, aLParam));

    return static_cast<LRESULT>(TRUE);
  }

  static WindowsDllInterceptor sTipTsfInterceptor;
  static WindowsDllInterceptor::FuncHookType<WINEVENTPROC>
      sProcessCaretEventsStub;
  static WindowsDllInterceptor::FuncHookType<decltype(&SendMessageTimeoutW)>
      sSendMessageTimeoutWStub;
  static StaticAutoPtr<TIPMessageHandler> sInstance;

  HHOOK mHook;
  UINT mMessages[7];
  uint32_t mA11yBlockCount;
};

WindowsDllInterceptor TIPMessageHandler::sTipTsfInterceptor;
WindowsDllInterceptor::FuncHookType<WINEVENTPROC>
    TIPMessageHandler::sProcessCaretEventsStub;
WindowsDllInterceptor::FuncHookType<decltype(&SendMessageTimeoutW)>
    TIPMessageHandler::sSendMessageTimeoutWStub;
StaticAutoPtr<TIPMessageHandler> TIPMessageHandler::sInstance;

}  // namespace mozilla

#endif  // defined(ACCESSIBILITY)

/**************************************************************
 **************************************************************
 **
 ** BLOCK: nsIWidget impl.
 **
 ** nsIWidget interface implementation, broken down into
 ** sections.
 **
 **************************************************************
 **************************************************************/

/**************************************************************
 *
 * SECTION: nsWindow construction and destruction
 *
 **************************************************************/

nsWindow::nsWindow(bool aIsChildWindow)
    : nsWindowBase(),
      mResizeState(NOT_RESIZING),
      mIsChildWindow(aIsChildWindow) {
  mIconSmall = nullptr;
  mIconBig = nullptr;
  mWnd = nullptr;
  mTransitionWnd = nullptr;
  mPaintDC = nullptr;
  mPrevWndProc = nullptr;
  mNativeDragTarget = nullptr;
  mDeviceNotifyHandle = nullptr;
  mInDtor = false;
  mIsVisible = false;
  mIsTopWidgetWindow = false;
  mUnicodeWidget = true;
  mDisplayPanFeedback = false;
  mTouchWindow = false;
  mFutureMarginsToUse = false;
  mCustomNonClient = false;
  mHideChrome = false;
  mFullscreenMode = false;
  mMousePresent = false;
  mMouseInDraggableArea = false;
  mDestroyCalled = false;
  mIsEarlyBlankWindow = false;
  mHasTaskbarIconBeenCreated = false;
  mMouseTransparent = false;
  mPickerDisplayCount = 0;
  mWindowType = eWindowType_child;
  mBorderStyle = eBorderStyle_default;
  mOldSizeMode = nsSizeMode_Normal;
  mLastSizeMode = nsSizeMode_Normal;
  mLastSize.width = 0;
  mLastSize.height = 0;
  mOldStyle = 0;
  mOldExStyle = 0;
  mPainting = 0;
  mLastKeyboardLayout = 0;
  mBlurSuppressLevel = 0;
  mLastPaintEndTime = TimeStamp::Now();
  mCachedHitTestPoint.x = 0;
  mCachedHitTestPoint.y = 0;
  mCachedHitTestTime = TimeStamp::Now();
  mCachedHitTestResult = 0;
#ifdef MOZ_XUL
  mTransparencyMode = eTransparencyOpaque;
  memset(&mGlassMargins, 0, sizeof mGlassMargins);
#endif
  DWORD background = ::GetSysColor(COLOR_BTNFACE);
  mBrush = ::CreateSolidBrush(NSRGB_2_COLOREF(background));
  mSendingSetText = false;
  mDefaultScale = -1.0;  // not yet set, will be calculated on first use
  mAspectRatio = 0.0;    // not yet set, will be calculated on first use

  mTaskbarPreview = nullptr;

  mCompositorWidgetDelegate = nullptr;

  // Global initialization
  if (!sInstanceCount) {
    // Global app registration id for Win7 and up. See
    // WinTaskbar.cpp for details.
    mozilla::widget::WinTaskbar::RegisterAppUserModelID();
    KeyboardLayout::GetInstance()->OnLayoutChange(::GetKeyboardLayout(0));
#if defined(ACCESSIBILITY)
    mozilla::TIPMessageHandler::Initialize();
#endif  // defined(ACCESSIBILITY)
    if (SUCCEEDED(::OleInitialize(nullptr))) {
      sIsOleInitialized = TRUE;
    }
    NS_ASSERTION(sIsOleInitialized, "***** OLE is not initialized!\n");
    MouseScrollHandler::Initialize();
    // Init theme data
    nsUXThemeData::UpdateNativeThemeInfo();
    RedirectedKeyDownMessageManager::Forget();
    if (mPointerEvents.ShouldEnableInkCollector()) {
      InkCollector::sInkCollector = new InkCollector();
    }
  }  // !sInstanceCount

  mIdleService = nullptr;

  mSizeConstraintsScale = GetDefaultScale().scale;
  mMaxTextureSize = -1;  // Will be calculated when layer manager is created.

  mRequestFxrOutputPending = false;

  sInstanceCount++;
}

nsWindow::~nsWindow() {
  mInDtor = true;

  // If the widget was released without calling Destroy() then the native window
  // still exists, and we need to destroy it. Destroy() will early-return if it
  // was already called. In any case it is important to call it before
  // destroying mPresentLock (cf. 1156182).
  Destroy();

  // Free app icon resources.  This must happen after `OnDestroy` (see bug
  // 708033).
  if (mIconSmall) ::DestroyIcon(mIconSmall);

  if (mIconBig) ::DestroyIcon(mIconBig);

  sInstanceCount--;

  // Global shutdown
  if (sInstanceCount == 0) {
    if (InkCollector::sInkCollector) {
      InkCollector::sInkCollector->Shutdown();
      InkCollector::sInkCollector = nullptr;
    }
    IMEHandler::Terminate();
    NS_IF_RELEASE(sCursorImgContainer);
    if (sIsOleInitialized) {
      ::OleFlushClipboard();
      ::OleUninitialize();
      sIsOleInitialized = FALSE;
    }
  }

  NS_IF_RELEASE(mNativeDragTarget);
}

/**************************************************************
 *
 * SECTION: nsIWidget::Create, nsIWidget::Destroy
 *
 * Creating and destroying windows for this widget.
 *
 **************************************************************/

// Allow Derived classes to modify the height that is passed
// when the window is created or resized.
int32_t nsWindow::GetHeight(int32_t aProposedHeight) { return aProposedHeight; }

static bool ShouldCacheTitleBarInfo(nsWindowType aWindowType,
                                    nsBorderStyle aBorderStyle) {
  return (aWindowType == eWindowType_toplevel) &&
         (aBorderStyle == eBorderStyle_default ||
          aBorderStyle == eBorderStyle_all) &&
         (!nsUXThemeData::sTitlebarInfoPopulatedThemed ||
          !nsUXThemeData::sTitlebarInfoPopulatedAero);
}

// Create the proper widget
nsresult nsWindow::Create(nsIWidget* aParent, nsNativeWidget aNativeParent,
                          const LayoutDeviceIntRect& aRect,
                          nsWidgetInitData* aInitData) {
  nsWidgetInitData defaultInitData;
  if (!aInitData) aInitData = &defaultInitData;

  mUnicodeWidget = aInitData->mUnicode;

  nsIWidget* baseParent =
      aInitData->mWindowType == eWindowType_dialog ||
              aInitData->mWindowType == eWindowType_toplevel ||
              aInitData->mWindowType == eWindowType_invisible
          ? nullptr
          : aParent;

  mIsTopWidgetWindow = (nullptr == baseParent);
  mBounds = aRect;

  // Ensure that the toolkit is created.
  nsToolkit::GetToolkit();

  BaseCreate(baseParent, aInitData);

  HWND parent;
  if (aParent) {  // has a nsIWidget parent
    parent = aParent ? (HWND)aParent->GetNativeData(NS_NATIVE_WINDOW) : nullptr;
    mParent = aParent;
  } else {  // has a nsNative parent
    parent = (HWND)aNativeParent;
    mParent =
        aNativeParent ? WinUtils::GetNSWindowPtr((HWND)aNativeParent) : nullptr;
  }

  mIsRTL = aInitData->mRTL;
  mOpeningAnimationSuppressed = aInitData->mIsAnimationSuppressed;
  mAlwaysOnTop = aInitData->mAlwaysOnTop;

  DWORD style = WindowStyle();
  DWORD extendedStyle = WindowExStyle();

  if (mWindowType == eWindowType_popup) {
    if (!aParent) {
      parent = nullptr;
    }

    if (!IsWin8OrLater() && HasBogusPopupsDropShadowOnMultiMonitor() &&
        ShouldUseOffMainThreadCompositing()) {
      extendedStyle |= WS_EX_COMPOSITED;
    }

    if (aInitData->mMouseTransparent) {
      // This flag makes the window transparent to mouse events
      mMouseTransparent = true;
      extendedStyle |= WS_EX_TRANSPARENT;
    }
  } else if (mWindowType == eWindowType_invisible) {
    // Make sure CreateWindowEx succeeds at creating a toplevel window
    style &= ~0x40000000;  // WS_CHILDWINDOW
  } else {
    // See if the caller wants to explictly set clip children and clip siblings
    if (aInitData->clipChildren) {
      style |= WS_CLIPCHILDREN;
    } else {
      style &= ~WS_CLIPCHILDREN;
    }
    if (aInitData->clipSiblings) {
      style |= WS_CLIPSIBLINGS;
    }
  }

  const wchar_t* className;
  if (aInitData->mDropShadow) {
    className = GetWindowPopupClass();
  } else {
    className = GetWindowClass();
  }
  // Plugins are created in the disabled state so that they can't
  // steal focus away from our main window.  This is especially
  // important if the plugin has loaded in a background tab.
  if (aInitData->mWindowType == eWindowType_plugin ||
      aInitData->mWindowType == eWindowType_plugin_ipc_chrome ||
      aInitData->mWindowType == eWindowType_plugin_ipc_content) {
    style |= WS_DISABLED;
  }
  mWnd = ::CreateWindowExW(extendedStyle, className, L"", style, aRect.X(),
                           aRect.Y(), aRect.Width(), GetHeight(aRect.Height()),
                           parent, nullptr, nsToolkit::mDllInstance, nullptr);

  if (!mWnd) {
    NS_WARNING("nsWindow CreateWindowEx failed.");
    return NS_ERROR_FAILURE;
  }

  mDeviceNotifyHandle = InputDeviceUtils::RegisterNotification(mWnd);

  // If mDefaultScale is set before mWnd has been set, it will have the scale of
  // the primary monitor, rather than the monitor that the window is actually
  // on. For non-popup windows this gets corrected by the WM_DPICHANGED message
  // which resets mDefaultScale, but for popup windows we don't reset
  // mDefaultScale on that message. In order to ensure that popup windows
  // spawned on a non-primary monitor end up with the correct scale, we reset
  // mDefaultScale here so that it gets recomputed using the correct monitor now
  // that we have a mWnd.
  mDefaultScale = -1.0;

  if (mIsRTL) {
    DWORD dwAttribute = TRUE;
    DwmSetWindowAttribute(mWnd, DWMWA_NONCLIENT_RTL_LAYOUT, &dwAttribute,
                          sizeof dwAttribute);
  }

  if (mOpeningAnimationSuppressed) {
    SuppressAnimation(true);
  }

  if (mAlwaysOnTop) {
    ::SetWindowPos(mWnd, HWND_TOPMOST, 0, 0, 0, 0,
                   SWP_NOMOVE | SWP_NOSIZE | SWP_NOACTIVATE);
  }

  if (!IsPlugin() && mWindowType != eWindowType_invisible &&
      MouseScrollHandler::Device::IsFakeScrollableWindowNeeded()) {
    // Ugly Thinkpad Driver Hack (Bugs 507222 and 594977)
    //
    // We create two zero-sized windows as descendants of the top-level window,
    // like so:
    //
    //   Top-level window (MozillaWindowClass)
    //     FAKETRACKPOINTSCROLLCONTAINER (MozillaWindowClass)
    //       FAKETRACKPOINTSCROLLABLE (MozillaWindowClass)
    //
    // We need to have the middle window, otherwise the Trackpoint driver
    // will fail to deliver scroll messages.  WM_MOUSEWHEEL messages are
    // sent to the FAKETRACKPOINTSCROLLABLE, which then propagate up the
    // window hierarchy until they are handled by nsWindow::WindowProc.
    // WM_HSCROLL messages are also sent to the FAKETRACKPOINTSCROLLABLE,
    // but these do not propagate automatically, so we have the window
    // procedure pretend that they were dispatched to the top-level window
    // instead.
    //
    // The FAKETRACKPOINTSCROLLABLE needs to have the specific window styles it
    // is given below so that it catches the Trackpoint driver's heuristics.
    HWND scrollContainerWnd = ::CreateWindowW(
        className, L"FAKETRACKPOINTSCROLLCONTAINER", WS_CHILD | WS_VISIBLE, 0,
        0, 0, 0, mWnd, nullptr, nsToolkit::mDllInstance, nullptr);
    HWND scrollableWnd = ::CreateWindowW(
        className, L"FAKETRACKPOINTSCROLLABLE",
        WS_CHILD | WS_VISIBLE | WS_VSCROLL | WS_TABSTOP | 0x30, 0, 0, 0, 0,
        scrollContainerWnd, nullptr, nsToolkit::mDllInstance, nullptr);

    // Give the FAKETRACKPOINTSCROLLABLE window a specific ID so that
    // WindowProcInternal can distinguish it from the top-level window
    // easily.
    ::SetWindowLongPtrW(scrollableWnd, GWLP_ID, eFakeTrackPointScrollableID);

    // Make FAKETRACKPOINTSCROLLABLE use nsWindow::WindowProc, and store the
    // old window procedure in its "user data".
    WNDPROC oldWndProc;
    if (mUnicodeWidget)
      oldWndProc = (WNDPROC)::SetWindowLongPtrW(scrollableWnd, GWLP_WNDPROC,
                                                (LONG_PTR)nsWindow::WindowProc);
    else
      oldWndProc = (WNDPROC)::SetWindowLongPtrA(scrollableWnd, GWLP_WNDPROC,
                                                (LONG_PTR)nsWindow::WindowProc);
    ::SetWindowLongPtrW(scrollableWnd, GWLP_USERDATA, (LONG_PTR)oldWndProc);
  }

  SubclassWindow(TRUE);

  // Starting with Windows XP, a process always runs within a terminal services
  // session. In order to play nicely with RDP, fast user switching, and the
  // lock screen, we should be handling WM_WTSSESSION_CHANGE. We must register
  // our HWND in order to receive this message.
  DebugOnly<BOOL> wtsRegistered =
      ::WTSRegisterSessionNotification(mWnd, NOTIFY_FOR_THIS_SESSION);
  NS_ASSERTION(wtsRegistered, "WTSRegisterSessionNotification failed!\n");

  mDefaultIMC.Init(this);
  IMEHandler::InitInputContext(this, mInputContext);

  // Do some initialization work, but only if (a) it hasn't already been done,
  // and (b) this is the hidden window (which is conveniently created before
  // any visible windows but after the profile has been initialized).
  if (!sHaveInitializedPrefs && mWindowType == eWindowType_invisible) {
    sSwitchKeyboardLayout =
        Preferences::GetBool("intl.keyboard.per_window_layout", false);
    sHaveInitializedPrefs = true;
  }

  // Query for command button metric data for rendering the titlebar. We
  // only do this once on the first window that has an actual titlebar
  if (ShouldCacheTitleBarInfo(mWindowType, mBorderStyle)) {
    nsUXThemeData::UpdateTitlebarInfo(mWnd);
  }

  static bool a11yPrimed = false;
  if (!a11yPrimed && mWindowType == eWindowType_toplevel) {
    a11yPrimed = true;
    if (Preferences::GetInt("accessibility.force_disabled", 0) == -1) {
      ::PostMessage(mWnd, MOZ_WM_STARTA11Y, 0, 0);
    }
  }
  return NS_OK;
}

// Close this nsWindow
void nsWindow::Destroy() {