nsTableCellFrame.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 nsTableCellFrame_h__
#define nsTableCellFrame_h__

#include "mozilla/Attributes.h"
#include "celldata.h"
#include "nsITableCellLayout.h"
#include "nscore.h"
#include "nsContainerFrame.h"
#include "mozilla/ComputedStyle.h"
#include "nsIPercentBSizeObserver.h"
#include "nsTArray.h"
#include "nsTableRowFrame.h"
#include "mozilla/WritingModes.h"

/**
 * nsTableCellFrame
 * data structure to maintain information about a single table cell's frame
 *
 * NOTE:  frames are not ref counted.  We expose addref and release here
 * so we can change that decsion in the future.  Users of nsITableCellLayout
 * should refcount correctly as if this object is being ref counted, though
 * no actual support is under the hood.
 *
 * @author  sclark
 */
class nsTableCellFrame : public nsContainerFrame,
                         public nsITableCellLayout,
                         public nsIPercentBSizeObserver
{
  typedef mozilla::gfx::DrawTarget DrawTarget;
  typedef mozilla::image::ImgDrawResult ImgDrawResult;

  friend nsTableCellFrame* NS_NewTableCellFrame(nsIPresShell*   aPresShell,
                                                ComputedStyle* aStyle,
                                                nsTableFrame* aTableFrame);

  nsTableCellFrame(ComputedStyle* aStyle, nsTableFrame* aTableFrame)
    : nsTableCellFrame(aStyle, aTableFrame, kClassID) {}

protected:
  typedef mozilla::WritingMode WritingMode;
  typedef mozilla::LogicalSide LogicalSide;
  typedef mozilla::LogicalMargin LogicalMargin;

public:
  NS_DECL_QUERYFRAME
  NS_DECL_FRAMEARENA_HELPERS(nsTableCellFrame)

  nsTableRowFrame* GetTableRowFrame() const
  {
    nsIFrame* parent = GetParent();
    MOZ_ASSERT(parent && parent->IsTableRowFrame());
    return static_cast<nsTableRowFrame*>(parent);
  }

  nsTableFrame* GetTableFrame() const
  {
    return GetTableRowFrame()->GetTableFrame();
  }

  virtual void Init(nsIContent*       aContent,
                    nsContainerFrame* aParent,
                    nsIFrame*         aPrevInFlow) override;

  virtual void DestroyFrom(nsIFrame* aDestructRoot, PostDestroyData& aPostDestroyData) override;

#ifdef ACCESSIBILITY
  virtual mozilla::a11y::AccType AccessibleType() override;
#endif

  virtual nsresult  AttributeChanged(int32_t         aNameSpaceID,
                                     nsAtom*        aAttribute,
                                     int32_t         aModType) override;

  /** @see nsIFrame::DidSetComputedStyle */
  virtual void DidSetComputedStyle(ComputedStyle* aOldComputedStyle) override;

#ifdef DEBUG
  // Our anonymous block frame is the content insertion frame so these
  // methods should never be called:
  virtual void AppendFrames(ChildListID     aListID,
                            nsFrameList&    aFrameList) override;
  virtual void InsertFrames(ChildListID     aListID,
                            nsIFrame*       aPrevFrame,
                            nsFrameList&    aFrameList) override;
  virtual void RemoveFrame(ChildListID     aListID,
                           nsIFrame*       aOldFrame) override;
#endif

  virtual nsContainerFrame* GetContentInsertionFrame() override {
    return PrincipalChildList().FirstChild()->GetContentInsertionFrame();
  }

  virtual nsMargin GetUsedMargin() const override;

  virtual void NotifyPercentBSize(const ReflowInput& aReflowInput) override;

  virtual bool NeedsToObserve(const ReflowInput& aReflowInput) override;

  virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                const nsDisplayListSet& aLists) override;

  virtual nsresult ProcessBorders(nsTableFrame* aFrame,
                                  nsDisplayListBuilder* aBuilder,
                                  const nsDisplayListSet& aLists);

  virtual nscoord GetMinISize(gfxContext *aRenderingContext) override;
  virtual nscoord GetPrefISize(gfxContext *aRenderingContext) override;
  IntrinsicISizeOffsetData IntrinsicISizeOffsets(nscoord aPercentageBasis =
                                                 NS_UNCONSTRAINEDSIZE) override;

  virtual void Reflow(nsPresContext*      aPresContext,
                      ReflowOutput& aDesiredSize,
                      const ReflowInput& aReflowInput,
                      nsReflowStatus&      aStatus) override;

#ifdef DEBUG_FRAME_DUMP
  virtual nsresult GetFrameName(nsAString& aResult) const override;
#endif

  void BlockDirAlignChild(mozilla::WritingMode aWM, nscoord aMaxAscent);

  /*
   * Get the value of vertical-align adjusted for CSS 2's rules for a
   * table cell, which means the result is always
   * NS_STYLE_VERTICAL_ALIGN_{TOP,MIDDLE,BOTTOM,BASELINE}.
   */
  virtual uint8_t GetVerticalAlign() const;

  bool HasVerticalAlignBaseline() const {
    return GetVerticalAlign() == NS_STYLE_VERTICAL_ALIGN_BASELINE;
  }

  bool CellHasVisibleContent(nscoord       aBSize,
                             nsTableFrame* tableFrame,
                             nsIFrame*     kidFrame);

  /**
   * Get the first-line baseline of the cell relative to its block-start border
   * edge, as if the cell were vertically aligned to the top of the row.
   */
  nscoord GetCellBaseline() const;

  /**
   * return the cell's specified row span. this is what was specified in the
   * content model or in the style info, and is always >= 0.
   * to get the effective row span (the actual value that applies), use GetEffectiveRowSpan()
   * @see nsTableFrame::GetEffectiveRowSpan()
   */
  int32_t GetRowSpan();

  // there is no set row index because row index depends on the cell's parent row only

  // Return our cell content frame.
  void AppendDirectlyOwnedAnonBoxes(nsTArray<OwnedAnonBox>& aResult) override;

  /*---------------- nsITableCellLayout methods ------------------------*/

  /**
   * return the cell's starting row index (starting at 0 for the first row).
   * for continued cell frames the row index is that of the cell's first-in-flow
   * and the column index (starting at 0 for the first column
   */
  NS_IMETHOD GetCellIndexes(int32_t &aRowIndex, int32_t &aColIndex) override;

  /** return the mapped cell's row index (starting at 0 for the first row) */
  uint32_t RowIndex() const
  {
    return static_cast<nsTableRowFrame*>(GetParent())->GetRowIndex();
  }

  /**
   * return the cell's specified col span. this is what was specified in the
   * content model or in the style info, and is always >= 1.
   * to get the effective col span (the actual value that applies), use GetEffectiveColSpan()
   * @see nsTableFrame::GetEffectiveColSpan()
   */
  int32_t GetColSpan();

  /** return the cell's column index (starting at 0 for the first column) */
  uint32_t ColIndex() const
  {
    // NOTE: We copy this from previous continuations, and we don't ever have
    // dynamic updates when tables split, so our mColIndex always matches our
    // first continuation's.
    MOZ_ASSERT(static_cast<nsTableCellFrame*>(FirstContinuation())->mColIndex ==
               mColIndex,
               "mColIndex out of sync with first continuation");
    return mColIndex;
  }
    
  void SetColIndex(int32_t aColIndex);

  /** return the available isize given to this frame during its last reflow */
  inline nscoord GetPriorAvailISize();

  /** set the available isize given to this frame during its last reflow */
  inline void SetPriorAvailISize(nscoord aPriorAvailISize);

  /** return the desired size returned by this frame during its last reflow */
  inline mozilla::LogicalSize GetDesiredSize();

  /** set the desired size returned by this frame during its last reflow */
  inline void SetDesiredSize(const ReflowOutput & aDesiredSize);

  bool GetContentEmpty() const;
  void SetContentEmpty(bool aContentEmpty);

  bool HasPctOverBSize();
  void SetHasPctOverBSize(bool aValue);

  nsTableCellFrame* GetNextCell() const
  {
    nsIFrame* sibling = GetNextSibling();
#ifdef DEBUG
    if (sibling) {
      nsTableCellFrame* cellFrame = do_QueryFrame(sibling);
      MOZ_ASSERT(cellFrame, "How do we have a non-cell sibling?");
    }
#endif // DEBUG
    return static_cast<nsTableCellFrame*>(sibling);
  }

  virtual LogicalMargin GetBorderWidth(WritingMode aWM) const;

  virtual ImgDrawResult PaintBackground(gfxContext&          aRenderingContext,
                                     const nsRect&        aDirtyRect,
                                     nsPoint              aPt,
                                     uint32_t             aFlags);

  void DecorateForSelection(DrawTarget* aDrawTarget, nsPoint aPt);

  virtual bool ComputeCustomOverflow(nsOverflowAreas& aOverflowAreas) override;

  virtual bool IsFrameOfType(uint32_t aFlags) const override
  {
    return nsContainerFrame::IsFrameOfType(aFlags & ~(nsIFrame::eTablePart));
  }

  virtual void InvalidateFrame(uint32_t aDisplayItemKey = 0, bool aRebuildDisplayItems = true) override;
  virtual void InvalidateFrameWithRect(const nsRect& aRect, uint32_t aDisplayItemKey = 0, bool aRebuildDisplayItems = true) override;
  virtual void InvalidateFrameForRemoval() override { InvalidateFrameSubtree(); }

  bool ShouldPaintBordersAndBackgrounds() const;

  bool ShouldPaintBackground(nsDisplayListBuilder* aBuilder);

protected:
  nsTableCellFrame(ComputedStyle* aStyle, nsTableFrame* aTableFrame,
                   ClassID aID);
  ~nsTableCellFrame();

  virtual LogicalSides
  GetLogicalSkipSides(const ReflowInput* aReflowInput = nullptr) const override;

  /**
   * GetBorderOverflow says how far the cell's own borders extend
   * outside its own bounds.  In the separated borders model this should
   * just be zero (as it is for most frames), but in the collapsed
   * borders model (for which nsBCTableCellFrame overrides this virtual
   * method), it considers the extents of the collapsed border.
   */
  virtual nsMargin GetBorderOverflow();

  friend class nsTableRowFrame;

  uint32_t     mColIndex;             // the starting column for this cell

  nscoord      mPriorAvailISize;      // the avail isize during the last reflow
  mozilla::LogicalSize mDesiredSize;  // the last desired inline and block size
};

inline nscoord nsTableCellFrame::GetPriorAvailISize()
{ return mPriorAvailISize; }

inline void nsTableCellFrame::SetPriorAvailISize(nscoord aPriorAvailISize)
{ mPriorAvailISize = aPriorAvailISize; }

inline mozilla::LogicalSize nsTableCellFrame::GetDesiredSize()
{ return mDesiredSize; }

inline void nsTableCellFrame::SetDesiredSize(const ReflowOutput & aDesiredSize)
{
  mozilla::WritingMode wm = aDesiredSize.GetWritingMode();
  mDesiredSize = aDesiredSize.Size(wm).ConvertTo(GetWritingMode(), wm);
}

inline bool nsTableCellFrame::GetContentEmpty() const
{
  return HasAnyStateBits(NS_TABLE_CELL_CONTENT_EMPTY);
}

inline void nsTableCellFrame::SetContentEmpty(bool aContentEmpty)
{
  if (aContentEmpty) {
    AddStateBits(NS_TABLE_CELL_CONTENT_EMPTY);
  } else {
    RemoveStateBits(NS_TABLE_CELL_CONTENT_EMPTY);
  }
}

inline bool nsTableCellFrame::HasPctOverBSize()
{
  return HasAnyStateBits(NS_TABLE_CELL_HAS_PCT_OVER_BSIZE);
}

inline void nsTableCellFrame::SetHasPctOverBSize(bool aValue)
{
  if (aValue) {
    AddStateBits(NS_TABLE_CELL_HAS_PCT_OVER_BSIZE);
  } else {
    RemoveStateBits(NS_TABLE_CELL_HAS_PCT_OVER_BSIZE);
  }
}

// nsBCTableCellFrame
class nsBCTableCellFrame final : public nsTableCellFrame
{
  typedef mozilla::image::ImgDrawResult ImgDrawResult;
public:
  NS_DECL_FRAMEARENA_HELPERS(nsBCTableCellFrame)

  nsBCTableCellFrame(ComputedStyle* aStyle, nsTableFrame* aTableFrame);

  ~nsBCTableCellFrame();

  virtual nsMargin GetUsedBorder() const override;

  // Get the *inner half of the border only*, in twips.
  virtual LogicalMargin GetBorderWidth(WritingMode aWM) const override;

  // Get the *inner half of the border only*, in pixels.
  BCPixelSize GetBorderWidth(LogicalSide aSide) const;

  // Set the full (both halves) width of the border
  void SetBorderWidth(LogicalSide aSide, BCPixelSize aPixelValue);

  virtual nsMargin GetBorderOverflow() override;

#ifdef DEBUG_FRAME_DUMP
  virtual nsresult GetFrameName(nsAString& aResult) const override;
#endif

  virtual ImgDrawResult PaintBackground(gfxContext&          aRenderingContext,
                                     const nsRect&        aDirtyRect,
                                     nsPoint              aPt,
                                     uint32_t             aFlags) override;

private:

  // These are the entire width of the border (the cell edge contains only
  // the inner half, per the macros in nsTablePainter.h).
  BCPixelSize mBStartBorder;
  BCPixelSize mIEndBorder;
  BCPixelSize mBEndBorder;
  BCPixelSize mIStartBorder;
};

// Implemented here because that's a sane-ish way to make the includes work out.
inline nsTableCellFrame* nsTableRowFrame::GetFirstCell() const
{
  nsIFrame* firstChild = mFrames.FirstChild();
#ifdef DEBUG
    if (firstChild) {
      nsTableCellFrame* cellFrame = do_QueryFrame(firstChild);
      MOZ_ASSERT(cellFrame, "How do we have a non-cell sibling?");
    }
#endif // DEBUG
  return static_cast<nsTableCellFrame*>(firstChild);
}

#endif