Mypal/layout/generic/nsIFrameInlines.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */

#ifndef nsIFrameInlines_h___
#define nsIFrameInlines_h___

#include "nsContainerFrame.h"
#include "nsPlaceholderFrame.h"
#include "nsStyleStructInlines.h"
#include "nsCSSAnonBoxes.h"
#include "nsFrameManager.h"

bool
nsIFrame::IsFlexItem() const
{
  return GetParent() &&
    GetParent()->GetType() == nsGkAtoms::flexContainerFrame &&
    !(GetStateBits() & NS_FRAME_OUT_OF_FLOW);
}

bool
nsIFrame::IsFlexOrGridContainer() const
{
  nsIAtom* t = GetType();
  return t == nsGkAtoms::flexContainerFrame ||
         t == nsGkAtoms::gridContainerFrame;
}

bool
nsIFrame::IsFlexOrGridItem() const
{
  return !(GetStateBits() & NS_FRAME_OUT_OF_FLOW) &&
         GetParent() &&
         GetParent()->IsFlexOrGridContainer();
}

bool
nsIFrame::IsTableCaption() const
{
  return StyleDisplay()->mDisplay == mozilla::StyleDisplay::TableCaption &&
    GetParent()->StyleContext()->GetPseudo() == nsCSSAnonBoxes::tableWrapper;
}

bool
nsIFrame::IsFloating() const
{
  return StyleDisplay()->IsFloating(this);
}

bool
nsIFrame::IsAbsPosContainingBlock() const
{
  return StyleDisplay()->IsAbsPosContainingBlock(this);
}

bool
nsIFrame::IsFixedPosContainingBlock() const
{
  return StyleDisplay()->IsFixedPosContainingBlock(this);
}

bool
nsIFrame::IsRelativelyPositioned() const
{
  return StyleDisplay()->IsRelativelyPositioned(this);
}

bool
nsIFrame::IsAbsolutelyPositioned() const
{
  return StyleDisplay()->IsAbsolutelyPositioned(this);
}

bool
nsIFrame::IsBlockInside() const
{
  return StyleDisplay()->IsBlockInside(this);
}

bool
nsIFrame::IsBlockOutside() const
{
  return StyleDisplay()->IsBlockOutside(this);
}

bool
nsIFrame::IsInlineOutside() const
{
  return StyleDisplay()->IsInlineOutside(this);
}

mozilla::StyleDisplay
nsIFrame::GetDisplay() const
{
  return StyleDisplay()->GetDisplay(this);
}

nscoord
nsIFrame::SynthesizeBaselineBOffsetFromMarginBox(
            mozilla::WritingMode aWM,
            BaselineSharingGroup aGroup) const
{
  MOZ_ASSERT(!aWM.IsOrthogonalTo(GetWritingMode()));
  auto margin = GetLogicalUsedMargin(aWM);
  if (aGroup == BaselineSharingGroup::eFirst) {
    if (aWM.IsAlphabeticalBaseline()) {
      // First baseline for inverted-line content is the block-start margin edge,
      // as the frame is in effect "flipped" for alignment purposes.
      return MOZ_UNLIKELY(aWM.IsLineInverted()) ? -margin.BStart(aWM)
                                                : BSize(aWM) + margin.BEnd(aWM);
    }
    nscoord marginBoxCenter = (BSize(aWM) + margin.BStartEnd(aWM)) / 2;
    return marginBoxCenter - margin.BStart(aWM);
  }
  MOZ_ASSERT(aGroup == BaselineSharingGroup::eLast);
  if (aWM.IsAlphabeticalBaseline()) {
    // Last baseline for inverted-line content is the block-start margin edge,
    // as the frame is in effect "flipped" for alignment purposes.
    return MOZ_UNLIKELY(aWM.IsLineInverted()) ? BSize(aWM) + margin.BStart(aWM)
                                              : -margin.BEnd(aWM);
  }
  // Round up for central baseline offset, to be consistent with eFirst.
  nscoord marginBoxSize = BSize(aWM) + margin.BStartEnd(aWM);
  nscoord marginBoxCenter = (marginBoxSize / 2) + (marginBoxSize % 2);
  return marginBoxCenter - margin.BEnd(aWM);
}

nscoord
nsIFrame::SynthesizeBaselineBOffsetFromBorderBox(
            mozilla::WritingMode aWM,
            BaselineSharingGroup aGroup) const
{
  MOZ_ASSERT(!aWM.IsOrthogonalTo(GetWritingMode()));
  nscoord borderBoxSize = BSize(aWM);
  if (aGroup == BaselineSharingGroup::eFirst) {
    return MOZ_LIKELY(aWM.IsAlphabeticalBaseline()) ? borderBoxSize
                                                    : borderBoxSize / 2;
  }
  MOZ_ASSERT(aGroup == BaselineSharingGroup::eLast);
  // Round up for central baseline offset, to be consistent with eFirst.
  auto borderBoxCenter = (borderBoxSize / 2) + (borderBoxSize % 2);
  return MOZ_LIKELY(aWM.IsAlphabeticalBaseline()) ? 0 : borderBoxCenter;
}

nscoord
nsIFrame::BaselineBOffset(mozilla::WritingMode aWM,
                          BaselineSharingGroup aBaselineGroup,
                          AlignmentContext     aAlignmentContext) const
{
  MOZ_ASSERT(!aWM.IsOrthogonalTo(GetWritingMode()));
  nscoord baseline;
  if (GetNaturalBaselineBOffset(aWM, aBaselineGroup, &baseline)) {
    return baseline;
  }
  if (aAlignmentContext == AlignmentContext::eInline) {
    return SynthesizeBaselineBOffsetFromMarginBox(aWM, aBaselineGroup);
  }
  // XXX AlignmentContext::eTable should use content box?
  return SynthesizeBaselineBOffsetFromBorderBox(aWM, aBaselineGroup);
}

nsContainerFrame*
nsIFrame::GetInFlowParent()
{
  if (GetStateBits() & NS_FRAME_OUT_OF_FLOW) {
    nsIFrame* ph = FirstContinuation()->GetProperty(nsIFrame::PlaceholderFrameProperty());
    return ph->GetParent();
  }

  return GetParent();
}

#endif