layout/xul/nsMenuPopupFrame.cpp
author Nika Layzell <nika@thelayzells.com>
Tue, 25 Sep 2018 17:34:53 +0200
changeset 507828 5e6dae0c1e5a4939ccd406f14607f7fafffd45a7
parent 504265 0e6ba097af01b9a61cae1bb3f49a0dd28a49797b
child 508163 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1448426 - Wrap windows.h to avoid problematic define statements, r=froydnj,glandium By default, windows.h exposes a large number of problematic define statements which are UpperCamelCase, such as a define from `CreateWindow` to `CreateWindow{A,W}`. As many of these names are generic (e.g. CreateFile, CreateWindow), they can mess up Gecko code that may legitimately have its own methods with the same names. The header also defines some traditional SCREAMING_SNAKE_CASE defines which can mess up our code by conflicting with local values. This patch adds a simple code generator which generates wrappers for these defines, and uses them to wrap the windows.h wrapper using the `stl_wrappers` mechanism, allowing us to use windows.h in more places. Differential Revision: https://phabricator.services.mozilla.com/D10932

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */

#include "nsMenuPopupFrame.h"
#include "nsGkAtoms.h"
#include "nsIContent.h"
#include "nsAtom.h"
#include "nsPresContext.h"
#include "mozilla/ComputedStyle.h"
#include "nsCSSRendering.h"
#include "nsNameSpaceManager.h"
#include "nsViewManager.h"
#include "nsWidgetsCID.h"
#include "nsMenuFrame.h"
#include "nsMenuBarFrame.h"
#include "nsPopupSetFrame.h"
#include "nsPIDOMWindow.h"
#include "nsIPresShell.h"
#include "nsFrameManager.h"
#include "nsIDocument.h"
#include "nsRect.h"
#include "nsIComponentManager.h"
#include "nsBoxLayoutState.h"
#include "nsIScrollableFrame.h"
#include "nsIPopupContainer.h"
#include "nsIDocShell.h"
#include "nsReadableUtils.h"
#include "nsUnicharUtils.h"
#include "nsLayoutUtils.h"
#include "nsContentUtils.h"
#include "nsCSSFrameConstructor.h"
#include "nsPIWindowRoot.h"
#include "nsIReflowCallback.h"
#include "nsBindingManager.h"
#include "nsIDocShellTreeOwner.h"
#include "nsIBaseWindow.h"
#include "nsISound.h"
#include "nsIScreenManager.h"
#include "nsIServiceManager.h"
#include "nsStyleConsts.h"
#include "nsTransitionManager.h"
#include "nsDisplayList.h"
#include "nsIDOMXULSelectCntrlItemEl.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/EventStateManager.h"
#include "mozilla/EventStates.h"
#include "mozilla/Preferences.h"
#include "mozilla/LookAndFeel.h"
#include "mozilla/MouseEvents.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/Event.h"
#include "mozilla/dom/KeyboardEvent.h"
#include "mozilla/dom/KeyboardEventBinding.h"
#include <algorithm>

using namespace mozilla;
using mozilla::dom::KeyboardEvent;
using mozilla::dom::Event;

int8_t nsMenuPopupFrame::sDefaultLevelIsTop = -1;

DOMTimeStamp nsMenuPopupFrame::sLastKeyTime = 0;

// XXX, kyle.yuan@sun.com, there are 4 definitions for the same purpose:
//  nsMenuPopupFrame.h, nsListControlFrame.cpp, listbox.xml, tree.xml
//  need to find a good place to put them together.
//  if someone changes one, please also change the other.
uint32_t nsMenuPopupFrame::sTimeoutOfIncrementalSearch = 1000;

const char kPrefIncrementalSearchTimeout[] =
  "ui.menu.incremental_search.timeout";

// NS_NewMenuPopupFrame
//
// Wrapper for creating a new menu popup container
//
nsIFrame*
NS_NewMenuPopupFrame(nsIPresShell* aPresShell, ComputedStyle* aStyle)
{
  return new (aPresShell) nsMenuPopupFrame(aStyle);
}

NS_IMPL_FRAMEARENA_HELPERS(nsMenuPopupFrame)

NS_QUERYFRAME_HEAD(nsMenuPopupFrame)
  NS_QUERYFRAME_ENTRY(nsMenuPopupFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsBoxFrame)

//
// nsMenuPopupFrame ctor
//
nsMenuPopupFrame::nsMenuPopupFrame(ComputedStyle* aStyle)
  : nsBoxFrame(aStyle, kClassID)
  , mCurrentMenu(nullptr)
  , mView(nullptr)
  , mPrefSize(-1, -1)
  , mXPos(0)
  , mYPos(0)
  , mAlignmentOffset(0)
  , mLastClientOffset(0, 0)
  , mPopupType(ePopupTypePanel)
  , mPopupState(ePopupClosed)
  , mPopupAlignment(POPUPALIGNMENT_NONE)
  , mPopupAnchor(POPUPALIGNMENT_NONE)
  , mPosition(POPUPPOSITION_UNKNOWN)
  , mFlip(FlipType_Default)
  , mIsOpenChanged(false)
  , mIsContextMenu(false)
  , mAdjustOffsetForContextMenu(false)
  , mGeneratedChildren(false)
  , mMenuCanOverlapOSBar(false)
  , mShouldAutoPosition(true)
  , mInContentShell(true)
  , mIsMenuLocked(false)
  , mMouseTransparent(false)
  , mIsOffset(false)
  , mHFlip(false)
  , mVFlip(false)
  , mPositionedOffset(0)
  , mAnchorType(MenuPopupAnchorType_Node)
{
  // the preference name is backwards here. True means that the 'top' level is
  // the default, and false means that the 'parent' level is the default.
  if (sDefaultLevelIsTop >= 0)
    return;
  sDefaultLevelIsTop =
    Preferences::GetBool("ui.panel.default_level_parent", false);
  Preferences::AddUintVarCache(&sTimeoutOfIncrementalSearch,
                               kPrefIncrementalSearchTimeout, 1000);
} // ctor

void
nsMenuPopupFrame::Init(nsIContent*       aContent,
                       nsContainerFrame* aParent,
                       nsIFrame*         aPrevInFlow)
{
  nsBoxFrame::Init(aContent, aParent, aPrevInFlow);

  // lookup if we're allowed to overlap the OS bar (menubar/taskbar) from the
  // look&feel object
  mMenuCanOverlapOSBar =
    LookAndFeel::GetInt(LookAndFeel::eIntID_MenusCanOverlapOSBar) != 0;

  CreatePopupView();

  // XXX Hack. The popup's view should float above all other views,
  // so we use the nsView::SetFloating() to tell the view manager
  // about that constraint.
  nsView* ourView = GetView();
  nsViewManager* viewManager = ourView->GetViewManager();
  viewManager->SetViewFloating(ourView, true);

  mPopupType = ePopupTypePanel;
  if (aContent->IsAnyOfXULElements(nsGkAtoms::menupopup, nsGkAtoms::popup)) {
    mPopupType = ePopupTypeMenu;
  } else if (aContent->IsXULElement(nsGkAtoms::tooltip)) {
    mPopupType = ePopupTypeTooltip;
  }

  nsCOMPtr<nsIDocShellTreeItem> dsti = PresContext()->GetDocShell();
  if (dsti && dsti->ItemType() == nsIDocShellTreeItem::typeChrome) {
    mInContentShell = false;
  }

  // To improve performance, create the widget for the popup only if it is not
  // a leaf. Leaf popups such as menus will create their widgets later when
  // the popup opens.
  if (!IsLeaf() && !ourView->HasWidget()) {
    CreateWidgetForView(ourView);
  }

  if (aContent->NodeInfo()->Equals(nsGkAtoms::tooltip, kNameSpaceID_XUL) &&
      aContent->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::_default,
                                         nsGkAtoms::_true, eIgnoreCase)) {
    nsIPopupContainer* popupContainer =
      nsIPopupContainer::GetPopupContainer(PresContext()->GetPresShell());
    if (popupContainer) {
      popupContainer->SetDefaultTooltip(aContent->AsElement());
    }
  }

  AddStateBits(NS_FRAME_IN_POPUP);
}

bool
nsMenuPopupFrame::HasRemoteContent() const
{
  return (!mInContentShell && mPopupType == ePopupTypePanel &&
          mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                             nsGkAtoms::remote,
                                             nsGkAtoms::_true, eIgnoreCase));
}

bool
nsMenuPopupFrame::IsNoAutoHide() const
{
  // Panels with noautohide="true" don't hide when the mouse is clicked
  // outside of them, or when another application is made active. Non-autohide
  // panels cannot be used in content windows.
  return (!mInContentShell && mPopupType == ePopupTypePanel &&
           mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                              nsGkAtoms::noautohide,
                                              nsGkAtoms::_true, eIgnoreCase));
}

nsPopupLevel
nsMenuPopupFrame::PopupLevel(bool aIsNoAutoHide) const
{
  // The popup level is determined as follows, in this order:
  //   1. non-panels (menus and tooltips) are always topmost
  //   2. any specified level attribute
  //   3. if a titlebar attribute is set, use the 'floating' level
  //   4. if this is a noautohide panel, use the 'parent' level
  //   5. use the platform-specific default level

  // If this is not a panel, this is always a top-most popup.
  if (mPopupType != ePopupTypePanel)
    return ePopupLevelTop;

  // If the level attribute has been set, use that.
  static Element::AttrValuesArray strings[] =
    {nsGkAtoms::top, nsGkAtoms::parent, nsGkAtoms::floating, nullptr};
  switch (mContent->AsElement()->FindAttrValueIn(kNameSpaceID_None,
                                                 nsGkAtoms::level, strings,
                                                 eCaseMatters)) {
    case 0:
      return ePopupLevelTop;
    case 1:
      return ePopupLevelParent;
    case 2:
      return ePopupLevelFloating;
  }

  // Panels with titlebars most likely want to be floating popups.
  if (mContent->AsElement()->HasAttr(kNameSpaceID_None, nsGkAtoms::titlebar))
    return ePopupLevelFloating;

  // If this panel is a noautohide panel, the default is the parent level.
  if (aIsNoAutoHide)
    return ePopupLevelParent;

  // Otherwise, the result depends on the platform.
  return sDefaultLevelIsTop ? ePopupLevelTop : ePopupLevelParent;
}

void
nsMenuPopupFrame::EnsureWidget(bool aRecreate)
{
  nsView* ourView = GetView();
  if (aRecreate) {
    ourView->DestroyWidget();
  }
  if (!ourView->HasWidget()) {
    NS_ASSERTION(!mGeneratedChildren && !PrincipalChildList().FirstChild(),
                 "Creating widget for MenuPopupFrame with children");
    CreateWidgetForView(ourView);
  }
}

nsresult
nsMenuPopupFrame::CreateWidgetForView(nsView* aView)
{
  // Create a widget for ourselves.
  nsWidgetInitData widgetData;
  widgetData.mWindowType = eWindowType_popup;
  widgetData.mBorderStyle = eBorderStyle_default;
  widgetData.clipSiblings = true;
  widgetData.mPopupHint = mPopupType;
  widgetData.mNoAutoHide = IsNoAutoHide();

  if (!mInContentShell) {
    // A drag popup may be used for non-static translucent drag feedback
    if (mPopupType == ePopupTypePanel &&
        mContent->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::type,
                                           nsGkAtoms::drag, eIgnoreCase)) {
      widgetData.mIsDragPopup = true;
    }

    // If mousethrough="always" is set directly on the popup, then the widget
    // should ignore mouse events, passing them through to the content behind.
    mMouseTransparent = GetStateBits() & NS_FRAME_MOUSE_THROUGH_ALWAYS;
    widgetData.mMouseTransparent = mMouseTransparent;
  }

  nsAutoString title;
  if (widgetData.mNoAutoHide) {
    if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                           nsGkAtoms::titlebar,
                                           nsGkAtoms::normal, eCaseMatters)) {
      widgetData.mBorderStyle = eBorderStyle_title;

      mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::label, title);

      if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::close,
                                             nsGkAtoms::_true, eCaseMatters)) {
        widgetData.mBorderStyle =
          static_cast<enum nsBorderStyle>(widgetData.mBorderStyle | eBorderStyle_close);
      }
    }
  }

  bool remote = HasRemoteContent();

  nsTransparencyMode mode = nsLayoutUtils::GetFrameTransparency(this, this);
  nsIContent* parentContent = GetContent()->GetParent();
  nsAtom *tag = nullptr;
  if (parentContent && parentContent->IsXULElement())
    tag = parentContent->NodeInfo()->NameAtom();
  widgetData.mHasRemoteContent = remote;
  widgetData.mSupportTranslucency = mode == eTransparencyTransparent;
  widgetData.mDropShadow = !(mode == eTransparencyTransparent || tag == nsGkAtoms::menulist);
  widgetData.mPopupLevel = PopupLevel(widgetData.mNoAutoHide);

  // panels which have a parent level need a parent widget. This allows them to
  // always appear in front of the parent window but behind other windows that
  // should be in front of it.
  nsCOMPtr<nsIWidget> parentWidget;
  if (widgetData.mPopupLevel != ePopupLevelTop) {
    nsCOMPtr<nsIDocShellTreeItem> dsti = PresContext()->GetDocShell();
    if (!dsti)
      return NS_ERROR_FAILURE;

    nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
    dsti->GetTreeOwner(getter_AddRefs(treeOwner));
    if (!treeOwner) return NS_ERROR_FAILURE;

    nsCOMPtr<nsIBaseWindow> baseWindow(do_QueryInterface(treeOwner));
    if (baseWindow)
      baseWindow->GetMainWidget(getter_AddRefs(parentWidget));
  }

  nsresult rv = aView->CreateWidgetForPopup(&widgetData, parentWidget,
                                            true, true);
  if (NS_FAILED(rv)) {
    return rv;
  }

  nsIWidget* widget = aView->GetWidget();
  widget->SetTransparencyMode(mode);
  widget->SetWindowShadowStyle(GetShadowStyle());

  // most popups don't have a title so avoid setting the title if there isn't one
  if (!title.IsEmpty()) {
    widget->SetTitle(title);
  }

  return NS_OK;
}

uint8_t
nsMenuPopupFrame::GetShadowStyle()
{
  uint8_t shadow = StyleUIReset()->mWindowShadow;
  if (shadow != NS_STYLE_WINDOW_SHADOW_DEFAULT)
    return shadow;

  switch (StyleDisplay()->mAppearance) {
    case StyleAppearance::Tooltip:
      return NS_STYLE_WINDOW_SHADOW_TOOLTIP;
    case StyleAppearance::Menupopup:
      return NS_STYLE_WINDOW_SHADOW_MENU;
    default:
      return NS_STYLE_WINDOW_SHADOW_DEFAULT;
  }
}

NS_IMETHODIMP nsXULPopupShownEvent::Run()
{
  nsMenuPopupFrame* popup = do_QueryFrame(mPopup->GetPrimaryFrame());
  // Set the state to visible if the popup is still open.
  if (popup && popup->IsOpen()) {
    popup->SetPopupState(ePopupShown);
  }

  WidgetMouseEvent event(true, eXULPopupShown, nullptr,
                         WidgetMouseEvent::eReal);
  return EventDispatcher::Dispatch(mPopup, mPresContext, &event);
}

NS_IMETHODIMP nsXULPopupShownEvent::HandleEvent(Event* aEvent)
{
  nsMenuPopupFrame* popup = do_QueryFrame(mPopup->GetPrimaryFrame());
  // Ignore events not targeted at the popup itself (ie targeted at
  // descendants):
  if (mPopup != aEvent->GetTarget()) {
    return NS_OK;
  }
  if (popup) {
    // ResetPopupShownDispatcher will delete the reference to this, so keep
    // another one until Run is finished.
    RefPtr<nsXULPopupShownEvent> event = this;
    // Only call Run if it the dispatcher was assigned. This avoids calling the
    // Run method if the transitionend event fires multiple times.
    if (popup->ClearPopupShownDispatcher()) {
      return Run();
    }
  }

  CancelListener();
  return NS_OK;
}

void nsXULPopupShownEvent::CancelListener()
{
  mPopup->RemoveSystemEventListener(NS_LITERAL_STRING("transitionend"), this, false);
}

NS_IMPL_ISUPPORTS_INHERITED(nsXULPopupShownEvent, Runnable, nsIDOMEventListener);

void
nsMenuPopupFrame::SetInitialChildList(ChildListID  aListID,
                                      nsFrameList& aChildList)
{
  // unless the list is empty, indicate that children have been generated.
  if (aListID == kPrincipalList && aChildList.NotEmpty()) {
    mGeneratedChildren = true;
  }
  nsBoxFrame::SetInitialChildList(aListID, aChildList);
}

bool
nsMenuPopupFrame::IsLeafDynamic() const
{
  if (mGeneratedChildren)
    return false;

  if (mPopupType != ePopupTypeMenu) {
    // any panel with a type attribute, such as the autocomplete popup,
    // is always generated right away.
    return !mContent->AsElement()->HasAttr(kNameSpaceID_None, nsGkAtoms::type);
  }

  // menu popups generate their child frames lazily only when opened, so
  // behave like a leaf frame. However, generate child frames normally if
  // the parent menu has a sizetopopup attribute. In this case the size of
  // the parent menu is dependent on the size of the popup, so the frames
  // need to exist in order to calculate this size.
  nsIContent* parentContent = mContent->GetParent();
  return parentContent &&
         (!parentContent->IsElement() ||
          !parentContent->AsElement()->HasAttr(kNameSpaceID_None,
                                               nsGkAtoms::sizetopopup));
}

void
nsMenuPopupFrame::UpdateWidgetProperties()
{
  if (nsIWidget* widget = GetWidget()) {
    widget->SetWindowOpacity(StyleUIReset()->mWindowOpacity);
    widget->SetWindowTransform(ComputeWidgetTransform());
  }
}

void
nsMenuPopupFrame::LayoutPopup(nsBoxLayoutState& aState, nsIFrame* aParentMenu,
                              nsIFrame* aAnchor, bool aSizedToPopup)
{
  if (!mGeneratedChildren)
    return;

  SchedulePaint();

  bool shouldPosition = true;
  bool isOpen = IsOpen();
  if (!isOpen) {
    // if the popup is not open, only do layout while showing or if the menu
    // is sized to the popup
    shouldPosition = (mPopupState == ePopupShowing || mPopupState == ePopupPositioning);
    if (!shouldPosition && !aSizedToPopup) {
      RemoveStateBits(NS_FRAME_FIRST_REFLOW);
      return;
    }
  }

  // if the popup has just been opened, make sure the scrolled window is at 0,0
  // Don't scroll menulists as they will scroll to their selected item on their own.
  if (mIsOpenChanged && !IsMenuList()) {
    nsIScrollableFrame *scrollframe = do_QueryFrame(nsBox::GetChildXULBox(this));
    if (scrollframe) {
      AutoWeakFrame weakFrame(this);
      scrollframe->ScrollTo(nsPoint(0,0), nsIScrollableFrame::INSTANT);
      if (!weakFrame.IsAlive()) {
        return;
      }
    }
  }

  // get the preferred, minimum and maximum size. If the menu is sized to the
  // popup, then the popup's width is the menu's width.
  nsSize prefSize = GetXULPrefSize(aState);
  nsSize minSize = GetXULMinSize(aState);
  nsSize maxSize = GetXULMaxSize(aState);

  if (aSizedToPopup) {
    prefSize.width = aParentMenu->GetRect().width;
  }
  prefSize = BoundsCheck(minSize, prefSize, maxSize);

  // if the size changed then set the bounds to be the preferred size
  bool sizeChanged = (mPrefSize != prefSize);
  if (sizeChanged) {
    SetXULBounds(aState, nsRect(0, 0, prefSize.width, prefSize.height), false);
    mPrefSize = prefSize;
  }

  bool needCallback = false;
  if (shouldPosition) {
    SetPopupPosition(aAnchor, false, aSizedToPopup, mPopupState == ePopupPositioning);
    needCallback = true;
  }

  nsRect bounds(GetRect());
  XULLayout(aState);

  // if the width or height changed, readjust the popup position. This is a
  // special case for tooltips where the preferred height doesn't include the
  // real height for its inline element, but does once it is laid out.
  // This is bug 228673 which doesn't have a simple fix.
  bool rePosition = shouldPosition && (mPosition == POPUPPOSITION_SELECTION);
  if (!aParentMenu) {
    nsSize newsize = GetSize();
    if (newsize.width > bounds.width || newsize.height > bounds.height) {
      // the size after layout was larger than the preferred size,
      // so set the preferred size accordingly
      mPrefSize = newsize;
      if (isOpen) {
        rePosition = true;
        needCallback = true;
      }
    }
  }

  if (rePosition) {
    SetPopupPosition(aAnchor, false, aSizedToPopup, false);
  }

  nsPresContext* pc = PresContext();
  nsView* view = GetView();

  if (sizeChanged) {
    // If the size of the popup changed, apply any size constraints.
    nsIWidget* widget = view->GetWidget();
    if (widget) {
      SetSizeConstraints(pc, widget, minSize, maxSize);
    }
  }

  if (isOpen) {
    nsViewManager* viewManager = view->GetViewManager();
    nsRect rect = GetRect();
    rect.x = rect.y = 0;
    rect.SizeTo(BoundsCheck(minSize, rect.Size(), maxSize));
    viewManager->ResizeView(view, rect);

    if (mPopupState == ePopupOpening) {
      mPopupState = ePopupVisible;
    }

    viewManager->SetViewVisibility(view, nsViewVisibility_kShow);
    SyncFrameViewProperties(view);
  }

  // finally, if the popup just opened, send a popupshown event
  bool openChanged = mIsOpenChanged;
  if (openChanged) {
    mIsOpenChanged = false;

    // Make sure the current selection in a menulist is visible.
    if (IsMenuList() && mCurrentMenu) {
      EnsureMenuItemIsVisible(mCurrentMenu);
    }

#ifndef MOZ_WIDGET_GTK
    // If the animate attribute is set to open, check for a transition and wait
    // for it to finish before firing the popupshown event.
    if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::animate,
                                           nsGkAtoms::open, eCaseMatters) &&
        nsLayoutUtils::HasCurrentTransitions(this)) {
      mPopupShownDispatcher = new nsXULPopupShownEvent(mContent, pc);
      mContent->AddSystemEventListener(NS_LITERAL_STRING("transitionend"),
                                       mPopupShownDispatcher, false, false);
      return;
    }
#endif

    // If there are no transitions, fire the popupshown event right away.
    nsCOMPtr<nsIRunnable> event = new nsXULPopupShownEvent(GetContent(), pc);
    mContent->OwnerDoc()->Dispatch(TaskCategory::Other,
                                   event.forget());
  }

  if (needCallback && !mReflowCallbackData.mPosted) {
    pc->PresShell()->PostReflowCallback(this);
    mReflowCallbackData.MarkPosted(aAnchor, aSizedToPopup, openChanged);
  }
}

bool
nsMenuPopupFrame::ReflowFinished()
{
  SetPopupPosition(mReflowCallbackData.mAnchor, false, mReflowCallbackData.mSizedToPopup, true);

  mReflowCallbackData.Clear();

  return false;
}

void
nsMenuPopupFrame::ReflowCallbackCanceled()
{
  mReflowCallbackData.Clear();
}

bool
nsMenuPopupFrame::IsMenuList()
{
  nsIFrame* parentMenu = GetParent();
  return (parentMenu && parentMenu->GetContent() &&
          parentMenu->GetContent()->IsXULElement(nsGkAtoms::menulist));
}

nsIContent*
nsMenuPopupFrame::GetTriggerContent(nsMenuPopupFrame* aMenuPopupFrame)
{
  while (aMenuPopupFrame) {
    if (aMenuPopupFrame->mTriggerContent)
      return aMenuPopupFrame->mTriggerContent;

    // check up the menu hierarchy until a popup with a trigger node is found
    nsMenuFrame* menuFrame = do_QueryFrame(aMenuPopupFrame->GetParent());
    if (!menuFrame)
      break;

    nsMenuParent* parentPopup = menuFrame->GetMenuParent();
    if (!parentPopup || !parentPopup->IsMenu())
      break;

    aMenuPopupFrame = static_cast<nsMenuPopupFrame *>(parentPopup);
  }

  return nullptr;
}

void
nsMenuPopupFrame::InitPositionFromAnchorAlign(const nsAString& aAnchor,
                                              const nsAString& aAlign)
{
  mTriggerContent = nullptr;

  if (aAnchor.EqualsLiteral("topleft"))
    mPopupAnchor = POPUPALIGNMENT_TOPLEFT;
  else if (aAnchor.EqualsLiteral("topright"))
    mPopupAnchor = POPUPALIGNMENT_TOPRIGHT;
  else if (aAnchor.EqualsLiteral("bottomleft"))
    mPopupAnchor = POPUPALIGNMENT_BOTTOMLEFT;
  else if (aAnchor.EqualsLiteral("bottomright"))
    mPopupAnchor = POPUPALIGNMENT_BOTTOMRIGHT;
  else if (aAnchor.EqualsLiteral("leftcenter"))
    mPopupAnchor = POPUPALIGNMENT_LEFTCENTER;
  else if (aAnchor.EqualsLiteral("rightcenter"))
    mPopupAnchor = POPUPALIGNMENT_RIGHTCENTER;
  else if (aAnchor.EqualsLiteral("topcenter"))
    mPopupAnchor = POPUPALIGNMENT_TOPCENTER;
  else if (aAnchor.EqualsLiteral("bottomcenter"))
    mPopupAnchor = POPUPALIGNMENT_BOTTOMCENTER;
  else
    mPopupAnchor = POPUPALIGNMENT_NONE;

  if (aAlign.EqualsLiteral("topleft"))
    mPopupAlignment = POPUPALIGNMENT_TOPLEFT;
  else if (aAlign.EqualsLiteral("topright"))
    mPopupAlignment = POPUPALIGNMENT_TOPRIGHT;
  else if (aAlign.EqualsLiteral("bottomleft"))
    mPopupAlignment = POPUPALIGNMENT_BOTTOMLEFT;
  else if (aAlign.EqualsLiteral("bottomright"))
    mPopupAlignment = POPUPALIGNMENT_BOTTOMRIGHT;
  else
    mPopupAlignment = POPUPALIGNMENT_NONE;

  mPosition = POPUPPOSITION_UNKNOWN;
}

void
nsMenuPopupFrame::InitializePopup(nsIContent* aAnchorContent,
                                  nsIContent* aTriggerContent,
                                  const nsAString& aPosition,
                                  int32_t aXPos, int32_t aYPos,
                                  MenuPopupAnchorType aAnchorType,
                                  bool aAttributesOverride)
{
  EnsureWidget();

  mPopupState = ePopupShowing;
  mAnchorContent = aAnchorContent;
  mTriggerContent = aTriggerContent;
  mXPos = aXPos;
  mYPos = aYPos;
  mAdjustOffsetForContextMenu = false;
  mVFlip = false;
  mHFlip = false;
  mAlignmentOffset = 0;
  mPositionedOffset = 0;

  mAnchorType = aAnchorType;

  // if aAttributesOverride is true, then the popupanchor, popupalign and
  // position attributes on the <popup> override those values passed in.
  // If false, those attributes are only used if the values passed in are empty
  if (aAnchorContent || aAnchorType == MenuPopupAnchorType_Rect) {
    nsAutoString anchor, align, position, flip;
    mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::popupanchor, anchor);
    mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::popupalign, align);
    mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::position, position);
    mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::flip, flip);

    if (aAttributesOverride) {
      // if the attributes are set, clear the offset position. Otherwise,
      // the offset is used to adjust the position from the anchor point
      if (anchor.IsEmpty() && align.IsEmpty() && position.IsEmpty())
        position.Assign(aPosition);
      else
        mXPos = mYPos = 0;
    }
    else if (!aPosition.IsEmpty()) {
      position.Assign(aPosition);
    }

    if (flip.EqualsLiteral("none")) {
      mFlip = FlipType_None;
    } else if (flip.EqualsLiteral("both")) {
      mFlip = FlipType_Both;
    } else if (flip.EqualsLiteral("slide")) {
      mFlip = FlipType_Slide;
    }

    position.CompressWhitespace();
    int32_t spaceIdx = position.FindChar(' ');
    // if there is a space in the position, assume it is the anchor and
    // alignment as two separate tokens.
    if (spaceIdx >= 0) {
      InitPositionFromAnchorAlign(Substring(position, 0, spaceIdx), Substring(position, spaceIdx + 1));
    }
    else if (position.EqualsLiteral("before_start")) {
      mPopupAnchor = POPUPALIGNMENT_TOPLEFT;
      mPopupAlignment = POPUPALIGNMENT_BOTTOMLEFT;
      mPosition = POPUPPOSITION_BEFORESTART;
    }
    else if (position.EqualsLiteral("before_end")) {
      mPopupAnchor = POPUPALIGNMENT_TOPRIGHT;
      mPopupAlignment = POPUPALIGNMENT_BOTTOMRIGHT;
      mPosition = POPUPPOSITION_BEFOREEND;
    }
    else if (position.EqualsLiteral("after_start")) {
      mPopupAnchor = POPUPALIGNMENT_BOTTOMLEFT;
      mPopupAlignment = POPUPALIGNMENT_TOPLEFT;
      mPosition = POPUPPOSITION_AFTERSTART;
    }
    else if (position.EqualsLiteral("after_end")) {
      mPopupAnchor = POPUPALIGNMENT_BOTTOMRIGHT;
      mPopupAlignment = POPUPALIGNMENT_TOPRIGHT;
      mPosition = POPUPPOSITION_AFTEREND;
    }
    else if (position.EqualsLiteral("start_before")) {
      mPopupAnchor = POPUPALIGNMENT_TOPLEFT;
      mPopupAlignment = POPUPALIGNMENT_TOPRIGHT;
      mPosition = POPUPPOSITION_STARTBEFORE;
    }
    else if (position.EqualsLiteral("start_after")) {
      mPopupAnchor = POPUPALIGNMENT_BOTTOMLEFT;
      mPopupAlignment = POPUPALIGNMENT_BOTTOMRIGHT;
      mPosition = POPUPPOSITION_STARTAFTER;
    }
    else if (position.EqualsLiteral("end_before")) {
      mPopupAnchor = POPUPALIGNMENT_TOPRIGHT;
      mPopupAlignment = POPUPALIGNMENT_TOPLEFT;
      mPosition = POPUPPOSITION_ENDBEFORE;
    }
    else if (position.EqualsLiteral("end_after")) {
      mPopupAnchor = POPUPALIGNMENT_BOTTOMRIGHT;
      mPopupAlignment = POPUPALIGNMENT_BOTTOMLEFT;
      mPosition = POPUPPOSITION_ENDAFTER;
    }
    else if (position.EqualsLiteral("overlap")) {
      mPopupAnchor = POPUPALIGNMENT_TOPLEFT;
      mPopupAlignment = POPUPALIGNMENT_TOPLEFT;
      mPosition = POPUPPOSITION_OVERLAP;
    }
    else if (position.EqualsLiteral("after_pointer")) {
      mPopupAnchor = POPUPALIGNMENT_TOPLEFT;
      mPopupAlignment = POPUPALIGNMENT_TOPLEFT;
      mPosition = POPUPPOSITION_AFTERPOINTER;
      // XXXndeakin this is supposed to anchor vertically after, but with the
      // horizontal position as the mouse pointer.
      mYPos += 21;
    }
    else if (position.EqualsLiteral("selection")) {
      mPopupAnchor = POPUPALIGNMENT_BOTTOMLEFT;
      mPopupAlignment = POPUPALIGNMENT_TOPLEFT;
      mPosition = POPUPPOSITION_SELECTION;
    }
    else {
      InitPositionFromAnchorAlign(anchor, align);
    }
  }

  mScreenRect = nsIntRect(-1, -1, 0, 0);

  if (aAttributesOverride) {
    // Use |left| and |top| dimension attributes to position the popup if
    // present, as they may have been persisted.
    nsAutoString left, top;
    mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::left, left);
    mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::top, top);

    nsresult err;
    if (!left.IsEmpty()) {
      int32_t x = left.ToInteger(&err);
      if (NS_SUCCEEDED(err))
        mScreenRect.x = x;
    }
    if (!top.IsEmpty()) {
      int32_t y = top.ToInteger(&err);
      if (NS_SUCCEEDED(err))
        mScreenRect.y = y;
    }
  }
}

void
nsMenuPopupFrame::InitializePopupAtScreen(nsIContent* aTriggerContent,
                                          int32_t aXPos, int32_t aYPos,
                                          bool aIsContextMenu)
{
  EnsureWidget();

  mPopupState = ePopupShowing;
  mAnchorContent = nullptr;
  mTriggerContent = aTriggerContent;
  mScreenRect = nsIntRect(aXPos, aYPos, 0, 0);
  mXPos = 0;
  mYPos = 0;
  mFlip = FlipType_Default;
  mPopupAnchor = POPUPALIGNMENT_NONE;
  mPopupAlignment = POPUPALIGNMENT_NONE;
  mPosition = POPUPPOSITION_UNKNOWN;
  mIsContextMenu = aIsContextMenu;
  mAdjustOffsetForContextMenu = aIsContextMenu;
  mAnchorType = MenuPopupAnchorType_Point;
  mPositionedOffset = 0;
}

void
nsMenuPopupFrame::InitializePopupAtRect(nsIContent* aTriggerContent,
                                        const nsAString& aPosition,
                                        const nsIntRect& aRect,
                                        bool aAttributesOverride)
{
  InitializePopup(nullptr, aTriggerContent, aPosition, 0, 0,
                  MenuPopupAnchorType_Rect, aAttributesOverride);
  mScreenRect = aRect;
}

void
nsMenuPopupFrame::ShowPopup(bool aIsContextMenu)
{
  mIsContextMenu = aIsContextMenu;

  InvalidateFrameSubtree();

  if (mPopupState == ePopupShowing || mPopupState == ePopupPositioning) {
    mPopupState = ePopupOpening;
    mIsOpenChanged = true;

    // Clear mouse capture when a popup is opened.
    if (mPopupType == ePopupTypeMenu) {
      EventStateManager* activeESM =
        static_cast<EventStateManager*>(
          EventStateManager::GetActiveEventStateManager());
      if (activeESM) {
        EventStateManager::ClearGlobalActiveContent(activeESM);
      }

      nsIPresShell::SetCapturingContent(nullptr, 0);
    }

    nsMenuFrame* menuFrame = do_QueryFrame(GetParent());
    if (menuFrame) {
      AutoWeakFrame weakFrame(this);
      menuFrame->PopupOpened();
      if (!weakFrame.IsAlive())
        return;
    }

    // do we need an actual reflow here?
    // is SetPopupPosition all that is needed?
    PresShell()->FrameNeedsReflow(this, nsIPresShell::eTreeChange,
                                  NS_FRAME_HAS_DIRTY_CHILDREN);

    if (mPopupType == ePopupTypeMenu) {
      nsCOMPtr<nsISound> sound(do_CreateInstance("@mozilla.org/sound;1"));
      if (sound)
        sound->PlayEventSound(nsISound::EVENT_MENU_POPUP);
    }
  }

  mShouldAutoPosition = true;
}

void
nsMenuPopupFrame::HidePopup(bool aDeselectMenu, nsPopupState aNewState)
{
  NS_ASSERTION(aNewState == ePopupClosed || aNewState == ePopupInvisible,
               "popup being set to unexpected state");

  ClearPopupShownDispatcher();

  // don't hide the popup when it isn't open
  if (mPopupState == ePopupClosed || mPopupState == ePopupShowing ||
      mPopupState == ePopupPositioning)
    return;

  // clear the trigger content if the popup is being closed. But don't clear
  // it if the popup is just being made invisible as a popuphiding or command
  // event may want to retrieve it.
  if (aNewState == ePopupClosed) {
    // if the popup had a trigger node set, clear the global window popup node
    // as well
    if (mTriggerContent) {
      nsIDocument* doc = mContent->GetUncomposedDoc();
      if (doc) {
        if (nsPIDOMWindowOuter* win = doc->GetWindow()) {
          nsCOMPtr<nsPIWindowRoot> root = win->GetTopWindowRoot();
          if (root) {
            root->SetPopupNode(nullptr);
          }
        }
      }
    }
    mTriggerContent = nullptr;
    mAnchorContent = nullptr;
  }

  // when invisible and about to be closed, HidePopup has already been called,
  // so just set the new state to closed and return
  if (mPopupState == ePopupInvisible) {
    if (aNewState == ePopupClosed)
      mPopupState = ePopupClosed;
    return;
  }

  mPopupState = aNewState;

  if (IsMenu())
    SetCurrentMenuItem(nullptr);

  mIncrementalString.Truncate();

  LockMenuUntilClosed(false);

  mIsOpenChanged = false;
  mCurrentMenu = nullptr; // make sure no current menu is set
  mHFlip = mVFlip = false;

  nsView* view = GetView();
  nsViewManager* viewManager = view->GetViewManager();
  viewManager->SetViewVisibility(view, nsViewVisibility_kHide);

  FireDOMEvent(NS_LITERAL_STRING("DOMMenuInactive"), mContent);

  // XXX, bug 137033, In Windows, if mouse is outside the window when the menupopup closes, no
  // mouse_enter/mouse_exit event will be fired to clear current hover state, we should clear it manually.
  // This code may not the best solution, but we can leave it here until we find the better approach.
  NS_ASSERTION(mContent->IsElement(), "How do we have a non-element?");
  EventStates state = mContent->AsElement()->State();

  if (state.HasState(NS_EVENT_STATE_HOVER)) {
    EventStateManager* esm = PresContext()->EventStateManager();
    esm->SetContentState(nullptr, NS_EVENT_STATE_HOVER);
  }

  nsMenuFrame* menuFrame = do_QueryFrame(GetParent());
  if (menuFrame) {
    menuFrame->PopupClosed(aDeselectMenu);
  }
}

uint32_t
nsMenuPopupFrame::GetXULLayoutFlags()
{
  return NS_FRAME_NO_SIZE_VIEW | NS_FRAME_NO_MOVE_VIEW | NS_FRAME_NO_VISIBILITY;
}

///////////////////////////////////////////////////////////////////////////////
// GetRootViewForPopup
//   Retrieves the view for the popup widget that contains the given frame.
//   If the given frame is not contained by a popup widget, return the
//   root view of the root viewmanager.
nsView*
nsMenuPopupFrame::GetRootViewForPopup(nsIFrame* aStartFrame)
{
  nsView* view = aStartFrame->GetClosestView();
  NS_ASSERTION(view, "frame must have a closest view!");
  while (view) {
    // Walk up the view hierarchy looking for a view whose widget has a
    // window type of eWindowType_popup - in other words a popup window
    // widget. If we find one, this is the view we want.
    nsIWidget* widget = view->GetWidget();
    if (widget && widget->WindowType() == eWindowType_popup) {
      return view;
    }

    nsView* temp = view->GetParent();
    if (!temp) {
      // Otherwise, we've walked all the way up to the root view and not
      // found a view for a popup window widget. Just return the root view.
      return view;
    }
    view = temp;
  }

  return nullptr;
}

nsPoint
nsMenuPopupFrame::AdjustPositionForAnchorAlign(nsRect& anchorRect,
                                               FlipStyle& aHFlip, FlipStyle& aVFlip)
{
  // flip the anchor and alignment for right-to-left
  int8_t popupAnchor(mPopupAnchor);
  int8_t popupAlign(mPopupAlignment);
  if (IsDirectionRTL()) {
    // no need to flip the centered anchor types vertically
    if (popupAnchor <= POPUPALIGNMENT_LEFTCENTER) {
      popupAnchor = -popupAnchor;
    }
    popupAlign = -popupAlign;
  }

  nsRect originalAnchorRect(anchorRect);

  // first, determine at which corner of the anchor the popup should appear
  nsPoint pnt;
  switch (popupAnchor) {
    case POPUPALIGNMENT_LEFTCENTER:
      pnt = nsPoint(anchorRect.x, anchorRect.y + anchorRect.height / 2);
      anchorRect.y = pnt.y;
      anchorRect.height = 0;
      break;
    case POPUPALIGNMENT_RIGHTCENTER:
      pnt = nsPoint(anchorRect.XMost(), anchorRect.y + anchorRect.height / 2);
      anchorRect.y = pnt.y;
      anchorRect.height = 0;
      break;
    case POPUPALIGNMENT_TOPCENTER:
      pnt = nsPoint(anchorRect.x + anchorRect.width / 2, anchorRect.y);
      anchorRect.x = pnt.x;
      anchorRect.width = 0;
      break;
    case POPUPALIGNMENT_BOTTOMCENTER:
      pnt = nsPoint(anchorRect.x + anchorRect.width / 2, anchorRect.YMost());
      anchorRect.x = pnt.x;
      anchorRect.width = 0;
      break;
    case POPUPALIGNMENT_TOPRIGHT:
      pnt = anchorRect.TopRight();
      break;
    case POPUPALIGNMENT_BOTTOMLEFT:
      pnt = anchorRect.BottomLeft();
      break;
    case POPUPALIGNMENT_BOTTOMRIGHT:
      pnt = anchorRect.BottomRight();
      break;
    case POPUPALIGNMENT_TOPLEFT:
    default:
      pnt = anchorRect.TopLeft();
      break;
  }

  // If the alignment is on the right edge of the popup, move the popup left
  // by the width. Similarly, if the alignment is on the bottom edge of the
  // popup, move the popup up by the height. In addition, account for the
  // margins of the popup on the edge on which it is aligned.
  nsMargin margin(0, 0, 0, 0);
  StyleMargin()->GetMargin(margin);
  switch (popupAlign) {
    case POPUPALIGNMENT_TOPRIGHT:
      pnt.MoveBy(-mRect.width - margin.right, margin.top);
      break;
    case POPUPALIGNMENT_BOTTOMLEFT:
      pnt.MoveBy(margin.left, -mRect.height - margin.bottom);
      break;
    case POPUPALIGNMENT_BOTTOMRIGHT:
      pnt.MoveBy(-mRect.width - margin.right, -mRect.height - margin.bottom);
      break;
    case POPUPALIGNMENT_TOPLEFT:
    default:
      pnt.MoveBy(margin.left, margin.top);
      break;
  }

  // If we aligning to the selected item in the popup, adjust the vertical
  // position by the height of the menulist label and the selected item's
  // position.
  if (mPosition == POPUPPOSITION_SELECTION) {
    MOZ_ASSERT(popupAnchor == POPUPALIGNMENT_BOTTOMLEFT ||
              popupAnchor == POPUPALIGNMENT_BOTTOMRIGHT);
    MOZ_ASSERT(popupAlign == POPUPALIGNMENT_TOPLEFT ||
               popupAlign == POPUPALIGNMENT_TOPRIGHT);

    // Only adjust the popup if it just opened, otherwise the popup will move around if its gets
    // resized or the selection changed. Cache the value in mPositionedOffset and use that instead
    // for any future calculations.
    if (mIsOpenChanged || mReflowCallbackData.mIsOpenChanged) {
      nsIFrame* selectedItemFrame = GetSelectedItemForAlignment();
      if (selectedItemFrame) {
        int32_t scrolly = 0;
        nsIScrollableFrame *scrollframe = do_QueryFrame(nsBox::GetChildXULBox(this));
        if (scrollframe) {
          scrolly = scrollframe->GetScrollPosition().y;
        }

        mPositionedOffset = originalAnchorRect.height + selectedItemFrame->GetRect().y - scrolly;
      }
    }

    pnt.y -= mPositionedOffset;
 }

  // Flipping horizontally is allowed as long as the popup is above or below
  // the anchor. This will happen if both the anchor and alignment are top or
  // both are bottom, but different values. Similarly, flipping vertically is
  // allowed if the popup is to the left or right of the anchor. In this case,
  // the values of the constants are such that both must be positive or both
  // must be negative. A special case, used for overlap, allows flipping
  // vertically as well.
  // If we are flipping in both directions, we want to set a flip style both
  // horizontally and vertically. However, we want to flip on the inside edge
  // of the anchor. Consider the example of a typical dropdown menu.
  // Vertically, we flip the popup on the outside edges of the anchor menu,
  // however horizontally, we want to to use the inside edges so the popup
  // still appears underneath the anchor menu instead of floating off the
  // side of the menu.
  switch (popupAnchor) {
    case POPUPALIGNMENT_LEFTCENTER:
    case POPUPALIGNMENT_RIGHTCENTER:
      aHFlip = FlipStyle_Outside;
      aVFlip = FlipStyle_Inside;
      break;
    case POPUPALIGNMENT_TOPCENTER:
    case POPUPALIGNMENT_BOTTOMCENTER:
      aHFlip = FlipStyle_Inside;
      aVFlip = FlipStyle_Outside;
      break;
    default:
    {
      FlipStyle anchorEdge = mFlip == FlipType_Both ? FlipStyle_Inside : FlipStyle_None;
      aHFlip = (popupAnchor == -popupAlign) ? FlipStyle_Outside : anchorEdge;
      if (((popupAnchor > 0) == (popupAlign > 0)) ||
          (popupAnchor == POPUPALIGNMENT_TOPLEFT && popupAlign == POPUPALIGNMENT_TOPLEFT))
        aVFlip = FlipStyle_Outside;
      else
        aVFlip = anchorEdge;
      break;
    }
  }

  return pnt;
}

nsIFrame* nsMenuPopupFrame::GetSelectedItemForAlignment()
{
  // This method adjusts a menulist's popup such that the selected item is under the cursor, aligned
  // with the menulist label.
  nsCOMPtr<nsIDOMXULSelectControlElement> select = do_QueryInterface(mAnchorContent);
  if (!select) {
    // If there isn't an anchor, then try just getting the parent of the popup.
    select = do_QueryInterface(mContent->GetParent());
    if (!select) {
      return nullptr;
    }
  }

  nsCOMPtr<nsIDOMXULSelectControlItemElement> item;
  select->GetSelectedItem(getter_AddRefs(item));

  nsCOMPtr<nsIContent> selectedElement = do_QueryInterface(item);
  return selectedElement ? selectedElement->GetPrimaryFrame() : nullptr;
}

nscoord
nsMenuPopupFrame::SlideOrResize(nscoord& aScreenPoint, nscoord aSize,
                               nscoord aScreenBegin, nscoord aScreenEnd,
                               nscoord *aOffset)
{
  // The popup may be positioned such that either the left/top or bottom/right
  // is outside the screen - but never both.
  nscoord newPos =
    std::max(aScreenBegin, std::min(aScreenEnd - aSize, aScreenPoint));
  *aOffset = newPos - aScreenPoint;
  aScreenPoint = newPos;
  return std::min(aSize, aScreenEnd - aScreenPoint);
}

nscoord
nsMenuPopupFrame::FlipOrResize(nscoord& aScreenPoint, nscoord aSize,
                               nscoord aScreenBegin, nscoord aScreenEnd,
                               nscoord aAnchorBegin, nscoord aAnchorEnd,
                               nscoord aMarginBegin, nscoord aMarginEnd,
                               nscoord aOffsetForContextMenu, FlipStyle aFlip,
                               bool aEndAligned, bool* aFlipSide)
{
  // The flip side argument will be set to true if there wasn't room and we
  // flipped to the opposite side.
  *aFlipSide = false;

  // all of the coordinates used here are in app units relative to the screen
  nscoord popupSize = aSize;
  if (aScreenPoint < aScreenBegin) {
    // at its current position, the popup would extend past the left or top
    // edge of the screen, so it will have to be moved or resized.
    if (aFlip) {
      // for inside flips, we flip on the opposite side of the anchor
      nscoord startpos = aFlip == FlipStyle_Outside ? aAnchorBegin : aAnchorEnd;
      nscoord endpos = aFlip == FlipStyle_Outside ? aAnchorEnd : aAnchorBegin;

      // check whether there is more room to the left and right (or top and
      // bottom) of the anchor and put the popup on the side with more room.
      if (startpos - aScreenBegin >= aScreenEnd - endpos) {
        aScreenPoint = aScreenBegin;
        popupSize = startpos - aScreenPoint - aMarginEnd;
        *aFlipSide = !aEndAligned;
      }
      else {
        // If the newly calculated position is different than the existing
        // position, flip such that the popup is to the right or bottom of the
        // anchor point instead . However, when flipping use the same margin
        // size.
        nscoord newScreenPoint = endpos + aMarginEnd;
        if (newScreenPoint != aScreenPoint) {
          *aFlipSide = aEndAligned;
          aScreenPoint = newScreenPoint;
          // check if the new position is still off the right or bottom edge of
          // the screen. If so, resize the popup.
          if (aScreenPoint + aSize > aScreenEnd) {
            popupSize = aScreenEnd - aScreenPoint;
          }
        }
      }
    }
    else {
      aScreenPoint = aScreenBegin;
    }
  }
  else if (aScreenPoint + aSize > aScreenEnd) {
    // at its current position, the popup would extend past the right or
    // bottom edge of the screen, so it will have to be moved or resized.
    if (aFlip) {
      // for inside flips, we flip on the opposite side of the anchor
      nscoord startpos = aFlip == FlipStyle_Outside ? aAnchorBegin : aAnchorEnd;
      nscoord endpos = aFlip == FlipStyle_Outside ? aAnchorEnd : aAnchorBegin;

      // check whether there is more room to the left and right (or top and
      // bottom) of the anchor and put the popup on the side with more room.
      if (aScreenEnd - endpos >= startpos - aScreenBegin) {
        *aFlipSide = aEndAligned;
        if (mIsContextMenu) {
          aScreenPoint = aScreenEnd - aSize;
        }
        else {
          aScreenPoint = endpos + aMarginBegin;
          popupSize = aScreenEnd - aScreenPoint;
        }
      }
      else {
        // if the newly calculated position is different than the existing
        // position, we flip such that the popup is to the left or top of the
        // anchor point instead.
        nscoord newScreenPoint = startpos - aSize - aMarginBegin - std::max(aOffsetForContextMenu, 0);
        if (newScreenPoint != aScreenPoint) {
          *aFlipSide = !aEndAligned;
          aScreenPoint = newScreenPoint;

          // check if the new position is still off the left or top edge of the
          // screen. If so, resize the popup.
          if (aScreenPoint < aScreenBegin) {
            aScreenPoint = aScreenBegin;
            if (!mIsContextMenu) {
              popupSize = startpos - aScreenPoint - aMarginBegin;
            }
          }
        }
      }
    }
    else {
      aScreenPoint = aScreenEnd - aSize;
    }
  }

  // Make sure that the point is within the screen boundaries and that the
  // size isn't off the edge of the screen. This can happen when a large
  // positive or negative margin is used.
  if (aScreenPoint < aScreenBegin) {
    aScreenPoint = aScreenBegin;
  }
  if (aScreenPoint > aScreenEnd) {
    aScreenPoint = aScreenEnd - aSize;
  }

  // If popupSize ended up being negative, or the original size was actually
  // smaller than the calculated popup size, just use the original size instead.
  if (popupSize <= 0 || aSize < popupSize) {
    popupSize = aSize;
  }

  return std::min(popupSize, aScreenEnd - aScreenPoint);
}

nsRect
nsMenuPopupFrame::ComputeAnchorRect(nsPresContext* aRootPresContext, nsIFrame* aAnchorFrame)
{
  // Get the root frame for a reference
  nsIFrame* rootFrame = aRootPresContext->PresShell()->GetRootFrame();

  // The dimensions of the anchor
  nsRect anchorRect = aAnchorFrame->GetRectRelativeToSelf();

  // Relative to the root
  anchorRect = nsLayoutUtils::TransformFrameRectToAncestor(aAnchorFrame,
                                                           anchorRect,
                                                           rootFrame);
  // Relative to the screen
  anchorRect.MoveBy(rootFrame->GetScreenRectInAppUnits().TopLeft());

  // In its own app units
  return anchorRect.ScaleToOtherAppUnitsRoundOut(aRootPresContext->AppUnitsPerDevPixel(),
                                                 PresContext()->AppUnitsPerDevPixel());
}

nsresult
nsMenuPopupFrame::SetPopupPosition(nsIFrame* aAnchorFrame, bool aIsMove, bool aSizedToPopup, bool aNotify)
{
  if (!mShouldAutoPosition)
    return NS_OK;

  // If this is due to a move, return early if the popup hasn't been laid out
  // yet. On Windows, this can happen when using a drag popup before it opens.
  if (aIsMove && (mPrefSize.width == -1 || mPrefSize.height == -1)) {
    return NS_OK;
  }

  nsPresContext* presContext = PresContext();
  nsIFrame* rootFrame = presContext->PresShell()->GetRootFrame();
  NS_ASSERTION(rootFrame->GetView() && GetView() &&
               rootFrame->GetView() == GetView()->GetParent(),
               "rootFrame's view is not our view's parent???");

  // For anchored popups, the anchor rectangle. For non-anchored popups, the
  // size will be 0.
  nsRect anchorRect;

  // Width of the parent, used when aSizedToPopup is true.
  int32_t parentWidth = 0;

  bool anchored = IsAnchored();
  if (anchored || aSizedToPopup) {
    // In order to deal with transforms, we need the root prescontext:
    nsPresContext* rootPresContext = presContext->GetRootPresContext();

    // If we can't reach a root pres context, don't bother continuing:
    if (!rootPresContext) {
      return NS_OK;
    }

    // If anchored to a rectangle, use that rectangle. Otherwise, determine the
    // rectangle from the anchor.
    if (mAnchorType == MenuPopupAnchorType_Rect) {
      anchorRect = ToAppUnits(mScreenRect, AppUnitsPerCSSPixel());
    }
    else {
      // if the frame is not specified, use the anchor node passed to OpenPopup. If
      // that wasn't specified either, use the root frame. Note that mAnchorContent
      // might be a different document so its presshell must be used.
      if (!aAnchorFrame) {
        if (mAnchorContent) {
          aAnchorFrame = mAnchorContent->GetPrimaryFrame();
        }

        if (!aAnchorFrame) {
          aAnchorFrame = rootFrame;
          if (!aAnchorFrame)
            return NS_OK;
        }
      }

      anchorRect = ComputeAnchorRect(rootPresContext, aAnchorFrame);
    }

    // The width is needed when aSizedToPopup is true
    parentWidth = anchorRect.width;
  }

  // Set the popup's size to the preferred size. Below, this size will be
  // adjusted to fit on the screen or within the content area. If the anchor
  // is sized to the popup, use the anchor's width instead of the preferred
  // width. The preferred size should already be set by the parent frame.
  NS_ASSERTION(mPrefSize.width >= 0 || mPrefSize.height >= 0,
               "preferred size of popup not set");
  mRect.width = aSizedToPopup ? parentWidth : mPrefSize.width;
  mRect.height = mPrefSize.height;

  // If we're anchoring to a rect, and the rect is smaller than the preferred size
  // of the popup, change its width accordingly.
  if (mAnchorType == MenuPopupAnchorType_Rect &&
      parentWidth < mPrefSize.width) {
    mRect.width = mPrefSize.width;
  }

  // the screen position in app units where the popup should appear
  nsPoint screenPoint;

  // indicators of whether the popup should be flipped or resized.
  FlipStyle hFlip = FlipStyle_None, vFlip = FlipStyle_None;

  nsMargin margin(0, 0, 0, 0);
  StyleMargin()->GetMargin(margin);

  // the screen rectangle of the root frame, in dev pixels.
  nsRect rootScreenRect = rootFrame->GetScreenRectInAppUnits();

  nsDeviceContext* devContext = presContext->DeviceContext();
  nsPoint offsetForContextMenu;

  bool isNoAutoHide = IsNoAutoHide();
  nsPopupLevel popupLevel = PopupLevel(isNoAutoHide);

  if (anchored) {
    // if we are anchored, there are certain things we don't want to do when
    // repositioning the popup to fit on the screen, such as end up positioned
    // over the anchor, for instance a popup appearing over the menu label.
    // When doing this reposition, we want to move the popup to the side with
    // the most room. The combination of anchor and alignment dictate if we
    // readjust above/below or to the left/right.
    if (mAnchorContent || mAnchorType == MenuPopupAnchorType_Rect) {
      // move the popup according to the anchor and alignment. This will also
      // tell us which axis the popup is flush against in case we have to move
      // it around later. The AdjustPositionForAnchorAlign method accounts for
      // the popup's margin.
      screenPoint = AdjustPositionForAnchorAlign(anchorRect, hFlip, vFlip);
    }
    else {
      // with no anchor, the popup is positioned relative to the root frame
      anchorRect = rootScreenRect;
      screenPoint = anchorRect.TopLeft() + nsPoint(margin.left, margin.top);
    }

    // mXPos and mYPos specify an additonal offset passed to OpenPopup that
    // should be added to the position.  We also add the offset to the anchor
    // pos so a later flip/resize takes the offset into account.
    nscoord anchorXOffset = nsPresContext::CSSPixelsToAppUnits(mXPos);
    if (IsDirectionRTL()) {
      screenPoint.x -= anchorXOffset;
      anchorRect.x -= anchorXOffset;
    } else {
      screenPoint.x += anchorXOffset;
      anchorRect.x += anchorXOffset;
    }
    nscoord anchorYOffset = nsPresContext::CSSPixelsToAppUnits(mYPos);
    screenPoint.y += anchorYOffset;
    anchorRect.y += anchorYOffset;

    // If this is a noautohide popup, set the screen coordinates of the popup.
    // This way, the popup stays at the location where it was opened even when
    // the window is moved. Popups at the parent level follow the parent
    // window as it is moved and remained anchored, so we want to maintain the
    // anchoring instead.
    if (isNoAutoHide &&
        (popupLevel != ePopupLevelParent || mAnchorType == MenuPopupAnchorType_Rect)) {
      // Account for the margin that will end up being added to the screen coordinate
      // the next time SetPopupPosition is called.
      mAnchorType = MenuPopupAnchorType_Point;
      mScreenRect.x = nsPresContext::AppUnitsToIntCSSPixels(screenPoint.x - margin.left);
      mScreenRect.y = nsPresContext::AppUnitsToIntCSSPixels(screenPoint.y - margin.top);
    }
  }
  else {
    // The popup is positioned at a screen coordinate.
    // First convert the screen position in mScreenRect from CSS pixels into
    // device pixels, ignoring any zoom as mScreenRect holds unzoomed screen
    // coordinates.
    int32_t factor = devContext->AppUnitsPerDevPixelAtUnitFullZoom();

    // Depending on the platform, context menus should be offset by varying amounts
    // to ensure that they don't appear directly where the cursor is. Otherwise,
    // it is too easy to have the context menu close up again.
    if (mAdjustOffsetForContextMenu) {
      nsPoint offsetForContextMenuDev;
      offsetForContextMenuDev.x = nsPresContext::CSSPixelsToAppUnits(LookAndFeel::GetInt(
                                    LookAndFeel::eIntID_ContextMenuOffsetHorizontal)) / factor;
      offsetForContextMenuDev.y = nsPresContext::CSSPixelsToAppUnits(LookAndFeel::GetInt(
                                    LookAndFeel::eIntID_ContextMenuOffsetVertical)) / factor;
      offsetForContextMenu.x = presContext->DevPixelsToAppUnits(offsetForContextMenuDev.x);
      offsetForContextMenu.y = presContext->DevPixelsToAppUnits(offsetForContextMenuDev.y);
    }

    // next, convert into app units accounting for the zoom
    screenPoint.x = presContext->DevPixelsToAppUnits(
                      nsPresContext::CSSPixelsToAppUnits(mScreenRect.x) / factor);
    screenPoint.y = presContext->DevPixelsToAppUnits(
                      nsPresContext::CSSPixelsToAppUnits(mScreenRect.y) / factor);
    anchorRect = nsRect(screenPoint, nsSize(0, 0));

    // add the margins on the popup
    screenPoint.MoveBy(margin.left + offsetForContextMenu.x,
                       margin.top + offsetForContextMenu.y);

#ifdef XP_MACOSX
    // OSX tooltips follow standard flip rule but other popups flip horizontally not vertically
    if (mPopupType == ePopupTypeTooltip) {
        vFlip = FlipStyle_Outside;
    } else {
        hFlip = FlipStyle_Outside;
    }
#else
    // Other OS screen positioned popups can be flipped vertically but never horizontally
    vFlip = FlipStyle_Outside;
#endif // #ifdef XP_MACOSX
  }

  nscoord oldAlignmentOffset = mAlignmentOffset;

  // If a panel is being moved or has flip="none", don't constrain or flip it, in order to avoid
  // visual noise when moving windows between screens. However, if a panel is already constrained
  // or flipped (mIsOffset), then we want to continue to calculate this. Also, always do this for
  // content shells, so that the popup doesn't extend outside the containing frame.
  if (mInContentShell || (mFlip != FlipType_None &&
                          (!aIsMove || mIsOffset || mPopupType != ePopupTypePanel))) {
    int32_t appPerDev = presContext->AppUnitsPerDevPixel();
    LayoutDeviceIntRect anchorRectDevPix =
      LayoutDeviceIntRect::FromAppUnitsToNearest(anchorRect, appPerDev);
    LayoutDeviceIntRect rootScreenRectDevPix =
      LayoutDeviceIntRect::FromAppUnitsToNearest(rootScreenRect, appPerDev);
    LayoutDeviceIntRect screenRectDevPix =
      GetConstraintRect(anchorRectDevPix, rootScreenRectDevPix, popupLevel);
    nsRect screenRect =
      LayoutDeviceIntRect::ToAppUnits(screenRectDevPix, appPerDev);

    // Ensure that anchorRect is on screen.
    anchorRect = anchorRect.Intersect(screenRect);

    // shrink the the popup down if it is larger than the screen size
    if (mRect.width > screenRect.width)
      mRect.width = screenRect.width;
    if (mRect.height > screenRect.height)
      mRect.height = screenRect.height;

    // at this point the anchor (anchorRect) is within the available screen
    // area (screenRect) and the popup is known to be no larger than the screen.

    // We might want to "slide" an arrow if the panel is of the correct type -
    // but we can only slide on one axis - the other axis must be "flipped or
    // resized" as normal.
    bool slideHorizontal = false, slideVertical = false;
    if (mFlip == FlipType_Slide) {
      int8_t position = GetAlignmentPosition();
      slideHorizontal = position >= POPUPPOSITION_BEFORESTART &&
                        position <= POPUPPOSITION_AFTEREND;
      slideVertical = position >= POPUPPOSITION_STARTBEFORE &&
                      position <= POPUPPOSITION_ENDAFTER;
    }

    // Next, check if there is enough space to show the popup at full size when
    // positioned at screenPoint. If not, flip the popups to the opposite side
    // of their anchor point, or resize them as necessary.
    bool endAligned = IsDirectionRTL() ?
      mPopupAlignment == POPUPALIGNMENT_TOPLEFT || mPopupAlignment == POPUPALIGNMENT_BOTTOMLEFT :
      mPopupAlignment == POPUPALIGNMENT_TOPRIGHT || mPopupAlignment == POPUPALIGNMENT_BOTTOMRIGHT;
    nscoord preOffsetScreenPoint = screenPoint.x;
    if (slideHorizontal) {
      mRect.width = SlideOrResize(screenPoint.x, mRect.width, screenRect.x,
                                  screenRect.XMost(), &mAlignmentOffset);
    } else {
      mRect.width = FlipOrResize(screenPoint.x, mRect.width, screenRect.x,
                                 screenRect.XMost(), anchorRect.x, anchorRect.XMost(),
                                 margin.left, margin.right, offsetForContextMenu.x, hFlip,
                                 endAligned, &mHFlip);
    }
    mIsOffset = preOffsetScreenPoint != screenPoint.x;

    endAligned = mPopupAlignment == POPUPALIGNMENT_BOTTOMLEFT ||
                 mPopupAlignment == POPUPALIGNMENT_BOTTOMRIGHT;
    preOffsetScreenPoint = screenPoint.y;
    if (slideVertical) {
      mRect.height = SlideOrResize(screenPoint.y, mRect.height, screenRect.y,
                                  screenRect.YMost(), &mAlignmentOffset);
    } else {
      mRect.height = FlipOrResize(screenPoint.y, mRect.height, screenRect.y,
                                  screenRect.YMost(), anchorRect.y, anchorRect.YMost(),
                                  margin.top, margin.bottom, offsetForContextMenu.y, vFlip,
                                  endAligned, &mVFlip);
    }
    mIsOffset = mIsOffset || (preOffsetScreenPoint != screenPoint.y);

    NS_ASSERTION(screenPoint.x >= screenRect.x && screenPoint.y >= screenRect.y &&
                 screenPoint.x + mRect.width <= screenRect.XMost() &&
                 screenPoint.y + mRect.height <= screenRect.YMost(),
                 "Popup is offscreen");
  }

  // snap the popup's position in screen coordinates to device pixels,
  // see bug 622507, bug 961431
  screenPoint.x = presContext->RoundAppUnitsToNearestDevPixels(screenPoint.x);
  screenPoint.y = presContext->RoundAppUnitsToNearestDevPixels(screenPoint.y);

  // determine the x and y position of the view by subtracting the desired
  // screen position from the screen position of the root frame.
  nsPoint viewPoint = screenPoint - rootScreenRect.TopLeft();

  nsView* view = GetView();
  NS_ASSERTION(view, "popup with no view");

  // Offset the position by the width and height of the borders and titlebar.
  // Even though GetClientOffset should return (0, 0) when there is no
  // titlebar or borders, we skip these calculations anyway for non-panels
  // to save time since they will never have a titlebar.
  nsIWidget* widget = view->GetWidget();
  if (mPopupType == ePopupTypePanel && widget) {
    mLastClientOffset = widget->GetClientOffset();
    viewPoint.x += presContext->DevPixelsToAppUnits(mLastClientOffset.x);
    viewPoint.y += presContext->DevPixelsToAppUnits(mLastClientOffset.y);
  }

  presContext->GetPresShell()->GetViewManager()->
    MoveViewTo(view, viewPoint.x, viewPoint.y);

  // Now that we've positioned the view, sync up the frame's origin.
  nsBoxFrame::SetPosition(viewPoint - GetParent()->GetOffsetTo(rootFrame));

  if (aSizedToPopup) {
    nsBoxLayoutState state(PresContext());
    // XXXndeakin can parentSize.width still extend outside?
    SetXULBounds(state, mRect);
  }

  // If the popup is in the positioned state or if it is shown and the position
  // or size changed, dispatch a popuppositioned event if the popup wants it.
  nsIntRect newRect(screenPoint.x, screenPoint.y, mRect.width, mRect.height);
  if (mPopupState == ePopupPositioning ||
      (mPopupState == ePopupShown && !newRect.IsEqualEdges(mUsedScreenRect)) ||
      (mPopupState == ePopupShown && oldAlignmentOffset != mAlignmentOffset)) {
    mUsedScreenRect = newRect;
    if (aNotify) {
      nsXULPopupPositionedEvent::DispatchIfNeeded(mContent, false, false);
    }
  }

  return NS_OK;
}

/* virtual */ nsMenuFrame*
nsMenuPopupFrame::GetCurrentMenuItem()
{
  return mCurrentMenu;
}

LayoutDeviceIntRect
nsMenuPopupFrame::GetConstraintRect(const LayoutDeviceIntRect& aAnchorRect,
                                    const LayoutDeviceIntRect& aRootScreenRect,
                                    nsPopupLevel aPopupLevel)
{
  LayoutDeviceIntRect screenRectPixels;

  // determine the available screen space. It will be reduced by the OS chrome
  // such as menubars. It addition, for content shells, it will be the area of
  // the content rather than the screen.
  nsCOMPtr<nsIScreen> screen;
  nsCOMPtr<nsIScreenManager> sm(do_GetService("@mozilla.org/gfx/screenmanager;1"));
  if (sm) {
    // for content shells, get the screen where the root frame is located.
    // This is because we need to constrain the content to this content area,
    // so we should use the same screen. Otherwise, use the screen where the
    // anchor is located.
    DesktopToLayoutDeviceScale scale =
      PresContext()->DeviceContext()->GetDesktopToDeviceScale();
    DesktopRect rect =
      (mInContentShell ? aRootScreenRect : aAnchorRect) / scale;
    int32_t width = std::max(1, NSToIntRound(rect.width));
    int32_t height = std::max(1, NSToIntRound(rect.height));
    sm->ScreenForRect(rect.x, rect.y, width, height, getter_AddRefs(screen));
    if (screen) {
      // Non-top-level popups (which will always be panels)
      // should never overlap the OS bar:
      bool dontOverlapOSBar = aPopupLevel != ePopupLevelTop;
      // get the total screen area if the popup is allowed to overlap it.
      if (!dontOverlapOSBar && mMenuCanOverlapOSBar && !mInContentShell)
        screen->GetRect(&screenRectPixels.x, &screenRectPixels.y,
          &screenRectPixels.width, &screenRectPixels.height);
      else
        screen->GetAvailRect(&screenRectPixels.x, &screenRectPixels.y,
          &screenRectPixels.width, &screenRectPixels.height);
    }
  }

  if (mInContentShell) {
    // for content shells, clip to the client area rather than the screen area
    screenRectPixels.IntersectRect(screenRectPixels, aRootScreenRect);
  }
  else if (!mOverrideConstraintRect.IsEmpty()) {
    LayoutDeviceIntRect overrideConstrainRect =
      LayoutDeviceIntRect::FromAppUnitsToNearest(mOverrideConstraintRect,
                                                 PresContext()->AppUnitsPerDevPixel());
    // This is currently only used for <select> elements where we want to constrain
    // vertically to the screen but not horizontally, so do the intersection and then
    // reset the horizontal values.
    screenRectPixels.IntersectRect(screenRectPixels, overrideConstrainRect);
    screenRectPixels.x = overrideConstrainRect.x;
    screenRectPixels.width = overrideConstrainRect.width;
  }

  return screenRectPixels;
}

void nsMenuPopupFrame::CanAdjustEdges(Side aHorizontalSide,
                                      Side aVerticalSide,
                                      LayoutDeviceIntPoint& aChange)
{
  int8_t popupAlign(mPopupAlignment);
  if (IsDirectionRTL()) {
    popupAlign = -popupAlign;
  }

  if (aHorizontalSide == (mHFlip ? eSideRight : eSideLeft)) {
    if (popupAlign == POPUPALIGNMENT_TOPLEFT || popupAlign == POPUPALIGNMENT_BOTTOMLEFT) {
      aChange.x = 0;
    }
  }
  else if (aHorizontalSide == (mHFlip ? eSideLeft : eSideRight)) {
    if (popupAlign == POPUPALIGNMENT_TOPRIGHT || popupAlign == POPUPALIGNMENT_BOTTOMRIGHT) {
      aChange.x = 0;
    }
  }

  if (aVerticalSide == (mVFlip ? eSideBottom : eSideTop)) {
    if (popupAlign == POPUPALIGNMENT_TOPLEFT || popupAlign == POPUPALIGNMENT_TOPRIGHT) {
      aChange.y = 0;
    }
  }
  else if (aVerticalSide == (mVFlip ? eSideTop : eSideBottom)) {
    if (popupAlign == POPUPALIGNMENT_BOTTOMLEFT || popupAlign == POPUPALIGNMENT_BOTTOMRIGHT) {
      aChange.y = 0;
    }
  }
}

ConsumeOutsideClicksResult nsMenuPopupFrame::ConsumeOutsideClicks()
{
  if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                         nsGkAtoms::consumeoutsideclicks,
                                         nsGkAtoms::_true, eCaseMatters)) {
    return ConsumeOutsideClicks_True;
  }
  if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                         nsGkAtoms::consumeoutsideclicks,
                                         nsGkAtoms::_false, eCaseMatters)) {
    return ConsumeOutsideClicks_ParentOnly;
  }
  if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                         nsGkAtoms::consumeoutsideclicks,
                                         nsGkAtoms::never, eCaseMatters)) {
    return ConsumeOutsideClicks_Never;
  }

  nsCOMPtr<nsIContent> parentContent = mContent->GetParent();
  if (parentContent) {
    dom::NodeInfo *ni = parentContent->NodeInfo();
    if (ni->Equals(nsGkAtoms::menulist, kNameSpaceID_XUL)) {
      return ConsumeOutsideClicks_True;  // Consume outside clicks for combo boxes on all platforms
    }
#if defined(XP_WIN)
    // Don't consume outside clicks for menus in Windows
    if (ni->Equals(nsGkAtoms::menu, kNameSpaceID_XUL) ||
        ni->Equals(nsGkAtoms::popupset, kNameSpaceID_XUL) ||
        ((ni->Equals(nsGkAtoms::button, kNameSpaceID_XUL) ||
          ni->Equals(nsGkAtoms::toolbarbutton, kNameSpaceID_XUL)) &&
         parentContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                                 nsGkAtoms::type,
                                                 nsGkAtoms::menu,
                                                 eCaseMatters))) {
      return ConsumeOutsideClicks_Never;
    }
#endif
    if (ni->Equals(nsGkAtoms::textbox, kNameSpaceID_XUL)) {
      // Don't consume outside clicks for autocomplete widget
      if (parentContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                                  nsGkAtoms::type,
                                                  nsGkAtoms::autocomplete,
                                                  eCaseMatters)) {
        return ConsumeOutsideClicks_Never;
      }
    }
  }

  return ConsumeOutsideClicks_True;
}

// XXXroc this is megalame. Fossicking around for a frame of the right
// type is a recipe for disaster in the long term.
nsIScrollableFrame* nsMenuPopupFrame::GetScrollFrame(nsIFrame* aStart)
{
  if (!aStart)
    return nullptr;

  // try start frame and siblings
  nsIFrame* currFrame = aStart;
  do {
    nsIScrollableFrame* sf = do_QueryFrame(currFrame);
    if (sf)
      return sf;
    currFrame = currFrame->GetNextSibling();
  } while (currFrame);

  // try children
  currFrame = aStart;
  do {
    nsIFrame* childFrame = currFrame->PrincipalChildList().FirstChild();
    nsIScrollableFrame* sf = GetScrollFrame(childFrame);
    if (sf)
      return sf;
    currFrame = currFrame->GetNextSibling();
  } while (currFrame);

  return nullptr;
}

void nsMenuPopupFrame::EnsureMenuItemIsVisible(nsMenuFrame* aMenuItem)
{
  if (aMenuItem) {
    aMenuItem->PresShell()->ScrollFrameRectIntoView(
      aMenuItem,
      nsRect(nsPoint(0,0), aMenuItem->GetRect().Size()),
      nsIPresShell::ScrollAxis(),
      nsIPresShell::ScrollAxis(),
      nsIPresShell::SCROLL_OVERFLOW_HIDDEN |
      nsIPresShell::SCROLL_FIRST_ANCESTOR_ONLY);
  }
}

void nsMenuPopupFrame::ChangeByPage(bool aIsUp)
{
  // Only scroll by page within menulists.
  if (!IsMenuList()) {
    return;
  }

  nsMenuFrame* newMenu = nullptr;
  nsIFrame* currentMenu = mCurrentMenu;
  if (!currentMenu) {
    // If there is no current menu item, get the first item. When moving up,
    // just use this as the newMenu and leave currentMenu null so that no
    // check for a later element is performed. When moving down, set currentMenu
    // so that we look for one page down from the first item.
    newMenu = nsXULPopupManager::GetNextMenuItem(this, nullptr, true, false);
    if (!aIsUp) {
      currentMenu = newMenu;
    }
  }

  if (currentMenu) {
    nscoord scrollHeight = mRect.height;
    nsIScrollableFrame *scrollframe = GetScrollFrame(this);
    if (scrollframe) {
      scrollHeight = scrollframe->GetScrollPortRect().height;
    }

    // Get the position of the current item and add or subtract one popup's
    // height to or from it.
    nscoord targetPosition = aIsUp ? currentMenu->GetRect().YMost() - scrollHeight :
                                     currentMenu->GetRect().y + scrollHeight;

    // Indicates that the last visible child was a valid menuitem.
    bool lastWasValid = false;

    // Look for the next child which is just past the target position. This child
    // will need to be selected.
    while (currentMenu) {
      // Only consider menu frames.
      nsMenuFrame* menuFrame = do_QueryFrame(currentMenu);
      if (menuFrame &&
          nsXULPopupManager::IsValidMenuItem(menuFrame->GetContent(), true)) {

        // If the right position was found, break out. Otherwise, look for another item.
        if ((!aIsUp && currentMenu->GetRect().YMost() > targetPosition) ||
            (aIsUp && currentMenu->GetRect().y < targetPosition)) {

          // If the last visible child was not a valid menuitem or was disabled,
          // use this as the menu to select, skipping over any non-valid items at
          // the edge of the page.
          if (!lastWasValid) {
            newMenu = menuFrame;
          }

          break;
        }

        // Assign this item to newMenu. This item will be selected in case we
        // don't find any more.
        lastWasValid = true;
        newMenu = menuFrame;
      }
      else {
        lastWasValid = false;
      }

      currentMenu = aIsUp ? currentMenu->GetPrevSibling() :
                            currentMenu->GetNextSibling();
    }
  }

  // Select the new menuitem.
  if (newMenu) {
    ChangeMenuItem(newMenu, false, true);
  }
}

NS_IMETHODIMP nsMenuPopupFrame::SetCurrentMenuItem(nsMenuFrame* aMenuItem)
{
  if (mCurrentMenu == aMenuItem)
    return NS_OK;

  if (mCurrentMenu) {
    mCurrentMenu->SelectMenu(false);
  }

  if (aMenuItem) {
    EnsureMenuItemIsVisible(aMenuItem);
    aMenuItem->SelectMenu(true);
  }

  mCurrentMenu = aMenuItem;

  return NS_OK;
}

void
nsMenuPopupFrame::CurrentMenuIsBeingDestroyed()
{
  mCurrentMenu = nullptr;
}

NS_IMETHODIMP
nsMenuPopupFrame::ChangeMenuItem(nsMenuFrame* aMenuItem,
                                 bool aSelectFirstItem,
                                 bool aFromKey)
{
  if (mCurrentMenu == aMenuItem)
    return NS_OK;

  // When a context menu is open, the current menu is locked, and no change
  // to the menu is allowed.
  nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
  if (!mIsContextMenu && pm && pm->HasContextMenu(this))
    return NS_OK;

  // Unset the current child.
  if (mCurrentMenu) {
    mCurrentMenu->SelectMenu(false);
    nsMenuPopupFrame* popup = mCurrentMenu->GetPopup();
    if (popup) {
      if (mCurrentMenu->IsOpen()) {
        if (pm)
          pm->HidePopupAfterDelay(popup);
      }
    }
  }

  // Set the new child.
  if (aMenuItem) {
    EnsureMenuItemIsVisible(aMenuItem);
    aMenuItem->SelectMenu(true);

    // On Windows, a menulist should update its value whenever navigation was
    // done by the keyboard.
#ifdef XP_WIN
    if (aFromKey && IsOpen() && IsMenuList()) {
      // Fire a command event as the new item, but we don't want to close
      // the menu, blink it, or update any other state of the menuitem. The
      // command event will cause the item to be selected.
      nsContentUtils::DispatchXULCommand(aMenuItem->GetContent(), /* aTrusted = */ true,
                                         nullptr, PresShell(),
                                         false, false, false, false);
    }
#endif
  }

  mCurrentMenu = aMenuItem;

  return NS_OK;
}

nsMenuFrame*
nsMenuPopupFrame::Enter(WidgetGUIEvent* aEvent)
{
  mIncrementalString.Truncate();

  // Give it to the child.
  if (mCurrentMenu)
    return mCurrentMenu->Enter(aEvent);

  return nullptr;
}

nsMenuFrame*
nsMenuPopupFrame::FindMenuWithShortcut(KeyboardEvent* aKeyEvent, bool& doAction)
{
  uint32_t charCode = aKeyEvent->CharCode();
  uint32_t keyCode = aKeyEvent->KeyCode();

  doAction = false;

  // Enumerate over our list of frames.
  nsContainerFrame* immediateParent =
    nsXULPopupManager::ImmediateParentFrame(this);
  uint32_t matchCount = 0, matchShortcutCount = 0;
  bool foundActive = false;
  nsMenuFrame* frameBefore = nullptr;
  nsMenuFrame* frameAfter = nullptr;
  nsMenuFrame* frameShortcut = nullptr;

  nsIContent* parentContent = mContent->GetParent();

  bool isMenu = parentContent &&
                  !parentContent->NodeInfo()->Equals(nsGkAtoms::menulist, kNameSpaceID_XUL);

  DOMTimeStamp keyTime = aKeyEvent->TimeStamp();

  if (charCode == 0) {
    if (keyCode == dom::KeyboardEvent_Binding::DOM_VK_BACK_SPACE) {
      if (!isMenu && !mIncrementalString.IsEmpty()) {
        mIncrementalString.SetLength(mIncrementalString.Length() - 1);
        return nullptr;
      }
      else {
#ifdef XP_WIN
        nsCOMPtr<nsISound> soundInterface = do_CreateInstance("@mozilla.org/sound;1");
        if (soundInterface)
          soundInterface->Beep();
#endif  // #ifdef XP_WIN
      }
    }
    return nullptr;
  }
  else {
    char16_t uniChar = ToLowerCase(static_cast<char16_t>(charCode));
    if (isMenu) {
      // Menu supports only first-letter navigation
      mIncrementalString = uniChar;
    } else if (IsWithinIncrementalTime(keyTime)) {
      mIncrementalString.Append(uniChar);
    } else {
      // Interval too long, treat as new typing
      mIncrementalString = uniChar;
    }
  }

  // See bug 188199 & 192346, if all letters in incremental string are same, just try to match the first one
  nsAutoString incrementalString(mIncrementalString);
  uint32_t charIndex = 1, stringLength = incrementalString.Length();
  while (charIndex < stringLength && incrementalString[charIndex] == incrementalString[charIndex - 1]) {
    charIndex++;
  }
  if (charIndex == stringLength) {
    incrementalString.Truncate(1);
    stringLength = 1;
  }

  sLastKeyTime = keyTime;

  // NOTE: If you crashed here due to a bogus |immediateParent| it is
  //       possible that the menu whose shortcut is being looked up has
  //       been destroyed already.  One strategy would be to
  //       setTimeout(<func>,0) as detailed in:
  //       <http://bugzilla.mozilla.org/show_bug.cgi?id=126675#c32>
  nsIFrame* firstMenuItem = nsXULPopupManager::GetNextMenuItem(immediateParent, nullptr, true, false);
  nsIFrame* currFrame = firstMenuItem;

  int32_t menuAccessKey = -1;
  nsMenuBarListener::GetMenuAccessKey(&menuAccessKey);

  // We start searching from first child. This process is divided into two parts
  //   -- before current and after current -- by the current item
  while (currFrame) {
    nsIContent* current = currFrame->GetContent();
    nsAutoString textKey;
    bool isShortcut = false;
    if (current->IsElement()) {
      if (menuAccessKey >= 0) {
        // Get the shortcut attribute.
        current->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::accesskey,
                                      textKey);
      }
      isShortcut = !textKey.IsEmpty();
      if (textKey.IsEmpty()) { // No shortcut, try first letter
        current->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::label,
                                      textKey);
        if (textKey.IsEmpty()) // No label, try another attribute (value)
          current->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::value,
                                        textKey);
      }
    }

    if (StringBeginsWith(textKey, incrementalString,
                         nsCaseInsensitiveStringComparator())) {
      // mIncrementalString is a prefix of textKey
      nsMenuFrame* menu = do_QueryFrame(currFrame);
      if (menu) {
        // There is one match
        matchCount++;
        if (isShortcut) {
          // There is one shortcut-key match
          matchShortcutCount++;
          // Record the matched item. If there is only one matched shortcut item, do it
          frameShortcut = menu;
        }
        if (!foundActive) {
          // It's a first candidate item located before/on the current item
          if (!frameBefore)
            frameBefore = menu;
        }
        else {
          // It's a first candidate item located after the current item
          if (!frameAfter)
            frameAfter = menu;
        }
      }
      else
        return nullptr;
    }

    // Get the active status
    if (current->IsElement() &&
        current->AsElement()->AttrValueIs(kNameSpaceID_None,
                                          nsGkAtoms::menuactive,
                                          nsGkAtoms::_true, eCaseMatters)) {
      foundActive = true;
      if (stringLength > 1) {
        // If there is more than one char typed, the current item has highest priority,
        //   otherwise the item next to current has highest priority
        if (currFrame == frameBefore)
          return frameBefore;
      }
    }

    nsMenuFrame* menu = do_QueryFrame(currFrame);
    currFrame = nsXULPopupManager::GetNextMenuItem(immediateParent, menu, true, true);
    if (currFrame == firstMenuItem)
      break;
  }

  doAction = (isMenu && (matchCount == 1 || matchShortcutCount == 1));

  if (matchShortcutCount == 1) // We have one matched shortcut item
    return frameShortcut;
  if (frameAfter) // If we have matched item after the current, use it
    return frameAfter;
  else if (frameBefore) // If we haven't, use the item before the current
    return frameBefore;

  // If we don't match anything, rollback the last typing
  mIncrementalString.SetLength(mIncrementalString.Length() - 1);

  // didn't find a matching menu item
#ifdef XP_WIN
  // behavior on Windows - this item is in a menu popup off of the
  // menu bar, so beep and do nothing else
  if (isMenu) {
    nsCOMPtr<nsISound> soundInterface = do_CreateInstance("@mozilla.org/sound;1");
    if (soundInterface)
      soundInterface->Beep();
  }
#endif  // #ifdef XP_WIN

  return nullptr;
}

void
nsMenuPopupFrame::LockMenuUntilClosed(bool aLock)
{
  mIsMenuLocked = aLock;

  // Lock / unlock the parent, too.
  nsMenuFrame* menu = do_QueryFrame(GetParent());
  if (menu) {
    nsMenuParent* parentParent = menu->GetMenuParent();
    if (parentParent) {
      parentParent->LockMenuUntilClosed(aLock);
    }
  }
}

nsIWidget*
nsMenuPopupFrame::GetWidget()
{
  nsView * view = GetRootViewForPopup(this);
  if (!view)
    return nullptr;

  return view->GetWidget();
}

// helpers /////////////////////////////////////////////////////////////

nsresult
nsMenuPopupFrame::AttributeChanged(int32_t aNameSpaceID,
                                   nsAtom* aAttribute,
                                   int32_t aModType)

{
  nsresult rv = nsBoxFrame::AttributeChanged(aNameSpaceID, aAttribute,
                                             aModType);

  if (aAttribute == nsGkAtoms::left || aAttribute == nsGkAtoms::top)
    MoveToAttributePosition();

  if (aAttribute == nsGkAtoms::remote) {
    // When the remote attribute changes, we need to create a new widget to
    // ensure that it has the correct compositor and transparency settings to
    // match the new value.
    EnsureWidget(true);
  }

  if (aAttribute == nsGkAtoms::followanchor) {
    nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
    if (pm) {
      pm->UpdateFollowAnchor(this);
    }
  }

  if (aAttribute == nsGkAtoms::label) {
    // set the label for the titlebar
    nsView* view = GetView();
    if (view) {
      nsIWidget* widget = view->GetWidget();
      if (widget) {
        nsAutoString title;
        mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::label, title);
        if (!title.IsEmpty()) {
          widget->SetTitle(title);
        }
      }
    }
  } else if (aAttribute == nsGkAtoms::ignorekeys) {
    nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
    if (pm) {
      nsAutoString ignorekeys;
      mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::ignorekeys, ignorekeys);
      pm->UpdateIgnoreKeys(ignorekeys.EqualsLiteral("true"));
    }
  }

  return rv;
}

void
nsMenuPopupFrame::MoveToAttributePosition()
{
  // Move the widget around when the user sets the |left| and |top| attributes.
  // Note that this is not the best way to move the widget, as it results in lots
  // of FE notifications and is likely to be slow as molasses. Use |moveTo| on
  // the element if possible.
  nsAutoString left, top;
  mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::left, left);
  mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::top, top);
  nsresult err1, err2;
  mozilla::CSSIntPoint pos(left.ToInteger(&err1), top.ToInteger(&err2));

  if (NS_SUCCEEDED(err1) && NS_SUCCEEDED(err2))
    MoveTo(pos, false);
}

void
nsMenuPopupFrame::DestroyFrom(nsIFrame* aDestructRoot, PostDestroyData& aPostDestroyData)
{
  if (mReflowCallbackData.mPosted) {
    PresShell()->CancelReflowCallback(this);
    mReflowCallbackData.Clear();
  }

  nsMenuFrame* menu = do_QueryFrame(GetParent());
  if (menu) {
    // clear the open attribute on the parent menu
    nsContentUtils::AddScriptRunner(
      new nsUnsetAttrRunnable(menu->GetContent()->AsElement(), nsGkAtoms::open));
  }

  ClearPopupShownDispatcher();

  nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
  if (pm)
    pm->PopupDestroyed(this);

  nsIPopupContainer* popupContainer =
    nsIPopupContainer::GetPopupContainer(PresContext()->GetPresShell());
  if (popupContainer && popupContainer->GetDefaultTooltip() == mContent) {
    popupContainer->SetDefaultTooltip(nullptr);
  }

  nsBoxFrame::DestroyFrom(aDestructRoot, aPostDestroyData);
}


void
nsMenuPopupFrame::MoveTo(const CSSIntPoint& aPos, bool aUpdateAttrs)
{
  nsIWidget* widget = GetWidget();
  if ((mScreenRect.x == aPos.x && mScreenRect.y == aPos.y) &&
      (!widget || widget->GetClientOffset() == mLastClientOffset)) {
    return;
  }

  // reposition the popup at the specified coordinates. Don't clear the anchor
  // and position, because the popup can be reset to its anchor position by
  // using (-1, -1) as coordinates. Subtract off the margin as it will be
  // added to the position when SetPopupPosition is called.
  nsMargin margin(0, 0, 0, 0);
  StyleMargin()->GetMargin(margin);

  // Workaround for bug 788189.  See also bug 708278 comment #25 and following.
  if (mAdjustOffsetForContextMenu) {
    margin.left += nsPresContext::CSSPixelsToAppUnits(LookAndFeel::GetInt(
                     LookAndFeel::eIntID_ContextMenuOffsetHorizontal));
    margin.top += nsPresContext::CSSPixelsToAppUnits(LookAndFeel::GetInt(
                     LookAndFeel::eIntID_ContextMenuOffsetVertical));
  }

  mAnchorType = MenuPopupAnchorType_Point;
  mScreenRect.x = aPos.x - nsPresContext::AppUnitsToIntCSSPixels(margin.left);
  mScreenRect.y = aPos.y - nsPresContext::AppUnitsToIntCSSPixels(margin.top);

  SetPopupPosition(nullptr, true, false, true);

  RefPtr<Element> popup = mContent->AsElement();
  if (aUpdateAttrs && (popup->HasAttr(kNameSpaceID_None, nsGkAtoms::left) ||
                       popup->HasAttr(kNameSpaceID_None, nsGkAtoms::top)))
  {
    nsAutoString left, top;
    left.AppendInt(aPos.x);
    top.AppendInt(aPos.y);
    popup->SetAttr(kNameSpaceID_None, nsGkAtoms::left, left, false);
    popup->SetAttr(kNameSpaceID_None, nsGkAtoms::top, top, false);
  }
}

void
nsMenuPopupFrame::MoveToAnchor(nsIContent* aAnchorContent,
                               const nsAString& aPosition,
                               int32_t aXPos, int32_t aYPos,
                               bool aAttributesOverride)
{
  NS_ASSERTION(IsVisible(), "popup must be visible to move it");

  nsPopupState oldstate = mPopupState;
  InitializePopup(aAnchorContent, mTriggerContent, aPosition,
                  aXPos, aYPos, MenuPopupAnchorType_Node, aAttributesOverride);
  // InitializePopup changed the state so reset it.
  mPopupState = oldstate;

  // Pass false here so that flipping and adjusting to fit on the screen happen.
  SetPopupPosition(nullptr, false, false, true);
}

bool
nsMenuPopupFrame::GetAutoPosition()
{
  return mShouldAutoPosition;
}

void
nsMenuPopupFrame::SetAutoPosition(bool aShouldAutoPosition)
{
  mShouldAutoPosition = aShouldAutoPosition;
  nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
  if (pm) {
    pm->UpdateFollowAnchor(this);
  }
}

int8_t
nsMenuPopupFrame::GetAlignmentPosition() const
{
  // The code below handles most cases of alignment, anchor and position values. Those that are
  // not handled just return POPUPPOSITION_UNKNOWN.

  if (mPosition == POPUPPOSITION_OVERLAP || mPosition == POPUPPOSITION_AFTERPOINTER ||
      mPosition == POPUPPOSITION_SELECTION)
    return mPosition;

  int8_t position = mPosition;

  if (position == POPUPPOSITION_UNKNOWN) {
    switch (mPopupAnchor) {
      case POPUPALIGNMENT_BOTTOMCENTER:
        position = mPopupAlignment == POPUPALIGNMENT_TOPRIGHT ?
                     POPUPPOSITION_AFTEREND : POPUPPOSITION_AFTERSTART;
        break;
      case POPUPALIGNMENT_TOPCENTER:
        position = mPopupAlignment == POPUPALIGNMENT_BOTTOMRIGHT ?
                     POPUPPOSITION_BEFOREEND : POPUPPOSITION_BEFORESTART;
        break;
      case POPUPALIGNMENT_LEFTCENTER:
        position = mPopupAlignment == POPUPALIGNMENT_BOTTOMRIGHT ?
                     POPUPPOSITION_STARTAFTER : POPUPPOSITION_STARTBEFORE;
        break;
      case POPUPALIGNMENT_RIGHTCENTER:
        position = mPopupAlignment == POPUPALIGNMENT_BOTTOMLEFT ?
                     POPUPPOSITION_ENDAFTER : POPUPPOSITION_ENDBEFORE;
        break;
      default:
        break;
    }
  }

  if (mHFlip) {
    position = POPUPPOSITION_HFLIP(position);
  }

  if (mVFlip) {
    position = POPUPPOSITION_VFLIP(position);
  }

  return position;
}

/**
 * KEEP THIS IN SYNC WITH nsFrame::CreateView
 * as much as possible. Until we get rid of views finally...
 */
void
nsMenuPopupFrame::CreatePopupView()
{
  if (HasView()) {
    return;
  }

  nsViewManager* viewManager = PresContext()->GetPresShell()->GetViewManager();
  NS_ASSERTION(nullptr != viewManager, "null view manager");

  // Create a view
  nsView* parentView = viewManager->GetRootView();
  nsViewVisibility visibility = nsViewVisibility_kHide;
  int32_t zIndex = INT32_MAX;
  bool    autoZIndex = false;

  NS_ASSERTION(parentView, "no parent view");

  // Create a view
  nsView *view = viewManager->CreateView(GetRect(), parentView, visibility);
  viewManager->SetViewZIndex(view, autoZIndex, zIndex);
  // XXX put view last in document order until we can do better
  viewManager->InsertChild(parentView, view, nullptr, true);

  // Remember our view
  SetView(view);

  NS_FRAME_LOG(NS_FRAME_TRACE_CALLS,
    ("nsMenuPopupFrame::CreatePopupView: frame=%p view=%p", this, view));
}

bool
nsMenuPopupFrame::ShouldFollowAnchor()
{
  if (!mShouldAutoPosition ||
      mAnchorType != MenuPopupAnchorType_Node || !mAnchorContent) {
    return false;
  }

  // Follow anchor mode is used when followanchor="true" is set or for arrow panels.
  if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                         nsGkAtoms::followanchor,
                                         nsGkAtoms::_true, eCaseMatters)) {
    return true;
  }

  if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None,
                                         nsGkAtoms::followanchor,
                                         nsGkAtoms::_false, eCaseMatters)) {
    return false;
  }

  return (mPopupType == ePopupTypePanel &&
          mContent->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::type,
                                             nsGkAtoms::arrow, eCaseMatters));
}

bool
nsMenuPopupFrame::ShouldFollowAnchor(nsRect& aRect)
{
  if (!ShouldFollowAnchor()) {
    return false;
  }

  nsIFrame* anchorFrame = mAnchorContent->GetPrimaryFrame();
  if (anchorFrame) {
    nsPresContext* rootPresContext = PresContext()->GetRootPresContext();
    if (rootPresContext) {
      aRect = ComputeAnchorRect(rootPresContext, anchorFrame);
    }
  }

  return true;
}

void
nsMenuPopupFrame::CheckForAnchorChange(nsRect& aRect)
{
  // Don't update if the popup isn't visible or we shouldn't be following the anchor.
  if (!IsVisible() || !ShouldFollowAnchor()) {
    return;
  }

  bool shouldHide = false;

  nsPresContext* rootPresContext = PresContext()->GetRootPresContext();

  // If the frame for the anchor has gone away, hide the popup.
  nsIFrame* anchor = mAnchorContent->GetPrimaryFrame();
  if (!anchor || !rootPresContext) {
    shouldHide = true;
  } else if (!anchor->IsVisibleConsideringAncestors(VISIBILITY_CROSS_CHROME_CONTENT_BOUNDARY)) {
    // If the anchor is now inside something that is invisible, hide the popup.
    shouldHide = true;
  } else {
    // If the anchor is now inside a hidden parent popup, hide the popup.
    nsIFrame* frame = anchor;
    while (frame) {
      nsMenuPopupFrame* popup = do_QueryFrame(frame);
      if (popup && popup->PopupState() != ePopupShown) {
        shouldHide = true;
        break;
      }

      frame = frame->GetParent();
    }
  }

  if (shouldHide) {
    nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
    if (pm) {
      // As the caller will be iterating over the open popups, hide asyncronously.
      pm->HidePopup(mContent, false, true, true, false);
    }

    return;
  }

  nsRect anchorRect = ComputeAnchorRect(rootPresContext, anchor);

  // If the rectangles are different, move the popup.
  if (!anchorRect.IsEqualEdges(aRect)) {
    aRect = anchorRect;
    SetPopupPosition(nullptr, true, false, true);
  }
}