gecko/layout/generic/nsInlineFrame.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

/* rendering object for CSS display:inline objects */

#ifndef nsInlineFrame_h___
#define nsInlineFrame_h___

#include "nsHTMLContainerFrame.h"
#include "nsAbsoluteContainingBlock.h"
#include "nsLineLayout.h"

class nsAnonymousBlockFrame;

#define nsInlineFrameSuper nsHTMLContainerFrame

/**  In Bidi left (or right) margin/padding/border should be applied to left
 *  (or right) most frame (or a continuation frame).
 *  This state value shows if this frame is left (or right) most continuation
 *  or not.
 */
#define NS_INLINE_FRAME_BIDI_VISUAL_STATE_IS_SET     NS_FRAME_STATE_BIT(21)

#define NS_INLINE_FRAME_BIDI_VISUAL_IS_LEFT_MOST     NS_FRAME_STATE_BIT(22)

#define NS_INLINE_FRAME_BIDI_VISUAL_IS_RIGHT_MOST    NS_FRAME_STATE_BIT(23)

/**
 * Inline frame class.
 *
 * This class manages a list of child frames that are inline frames. Working with
 * nsLineLayout, the class will reflow and place inline frames on a line.
 */
class nsInlineFrame : public nsInlineFrameSuper
{
public:
  NS_DECL_QUERYFRAME_TARGET(nsInlineFrame)
  NS_DECL_QUERYFRAME
  NS_DECL_FRAMEARENA_HELPERS

  friend nsIFrame* NS_NewInlineFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);

  // nsIFrame overrides
  NS_IMETHOD BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                              const nsRect&           aDirtyRect,
                              const nsDisplayListSet& aLists);

#ifdef ACCESSIBILITY
  virtual already_AddRefed<nsAccessible> CreateAccessible();
#endif

#ifdef DEBUG
  NS_IMETHOD GetFrameName(nsAString& aResult) const;
#endif
  virtual nsIAtom* GetType() const;

  virtual PRBool IsFrameOfType(PRUint32 aFlags) const
  {
    return nsInlineFrameSuper::IsFrameOfType(aFlags &
      ~(nsIFrame::eBidiInlineContainer | nsIFrame::eLineParticipant));
  }

  virtual PRBool IsEmpty();
  virtual PRBool IsSelfEmpty();

  virtual PRBool PeekOffsetCharacter(PRBool aForward, PRInt32* aOffset,
                                     PRBool aRespectClusters = PR_TRUE);
  
  // nsIHTMLReflow overrides
  virtual void AddInlineMinWidth(nsIRenderingContext *aRenderingContext,
                                 InlineMinWidthData *aData);
  virtual void AddInlinePrefWidth(nsIRenderingContext *aRenderingContext,
                                  InlinePrefWidthData *aData);
  virtual nsSize ComputeSize(nsIRenderingContext *aRenderingContext,
                             nsSize aCBSize, nscoord aAvailableWidth,
                             nsSize aMargin, nsSize aBorder, nsSize aPadding,
                             PRBool aShrinkWrap);
  virtual nsRect ComputeTightBounds(gfxContext* aContext) const;
  NS_IMETHOD Reflow(nsPresContext* aPresContext,
                    nsHTMLReflowMetrics& aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus& aStatus);

  virtual PRBool CanContinueTextRun() const;

  virtual void PullOverflowsFromPrevInFlow();
  virtual nscoord GetBaseline() const;

  /**
   * Return true if the frame is leftmost frame or continuation.
   */
  PRBool IsLeftMost() const {
    // If the frame's bidi visual state is set, return is-leftmost state
    // else return true if it's the first continuation.
    return (GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_STATE_IS_SET)
             ? !!(GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_IS_LEFT_MOST)
             : (!GetPrevInFlow());
  }

  /**
   * Return true if the frame is rightmost frame or continuation.
   */
  PRBool IsRightMost() const {
    // If the frame's bidi visual state is set, return is-rightmost state
    // else return true if it's the last continuation.
    return (GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_STATE_IS_SET)
             ? !!(GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_IS_RIGHT_MOST)
             : (!GetNextInFlow());
  }

protected:
  // Additional reflow state used during our reflow methods
  struct InlineReflowState {
    nsIFrame* mPrevFrame;
    nsInlineFrame* mNextInFlow;
    nsIFrame*      mLineContainer;
    nsLineLayout*  mLineLayout;
    PRPackedBool mSetParentPointer;  // when reflowing child frame first set its
                                     // parent frame pointer

    InlineReflowState()  {
      mPrevFrame = nsnull;
      mNextInFlow = nsnull;
      mLineContainer = nsnull;
      mLineLayout = nsnull;
      mSetParentPointer = PR_FALSE;
    }
  };

  nsInlineFrame(nsStyleContext* aContext) : nsInlineFrameSuper(aContext) {}

  virtual PRIntn GetSkipSides() const;

  nsresult ReflowFrames(nsPresContext* aPresContext,
                        const nsHTMLReflowState& aReflowState,
                        InlineReflowState& rs,
                        nsHTMLReflowMetrics& aMetrics,
                        nsReflowStatus& aStatus);

  nsresult ReflowInlineFrame(nsPresContext* aPresContext,
                             const nsHTMLReflowState& aReflowState,
                             InlineReflowState& rs,
                             nsIFrame* aFrame,
                             nsReflowStatus& aStatus);

  /**
   * Reparent floats whose placeholders are inline descendants of aFrame from
   * whatever block they're currently parented by to aOurBlock.
   * @param aReparentSiblings if this is true, we follow aFrame's
   * GetNextSibling chain reparenting them all
   */
  void ReparentFloatsForInlineChild(nsIFrame* aOurBlock, nsIFrame* aFrame,
                                    PRBool aReparentSiblings);

  virtual nsIFrame* PullOneFrame(nsPresContext* aPresContext,
                                 InlineReflowState& rs,
                                 PRBool* aIsComplete);

  virtual void PushFrames(nsPresContext* aPresContext,
                          nsIFrame* aFromChild,
                          nsIFrame* aPrevSibling,
                          InlineReflowState& aState);
};

//----------------------------------------------------------------------

/**
 * Variation on inline-frame used to manage lines for line layout in
 * special situations (:first-line style in particular).
 */
class nsFirstLineFrame : public nsInlineFrame {
public:
  NS_DECL_FRAMEARENA_HELPERS

  friend nsIFrame* NS_NewFirstLineFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);

#ifdef DEBUG
  NS_IMETHOD GetFrameName(nsAString& aResult) const;
#endif
  virtual nsIAtom* GetType() const;
  NS_IMETHOD Reflow(nsPresContext* aPresContext,
                    nsHTMLReflowMetrics& aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus& aStatus);

  virtual void PullOverflowsFromPrevInFlow();

protected:
  nsFirstLineFrame(nsStyleContext* aContext) : nsInlineFrame(aContext) {}

  virtual nsIFrame* PullOneFrame(nsPresContext* aPresContext,
                                 InlineReflowState& rs,
                                 PRBool* aIsComplete);
};

//----------------------------------------------------------------------

// Derived class created for relatively positioned inline-level elements
// that acts as a containing block for child absolutely positioned
// elements

class nsPositionedInlineFrame : public nsInlineFrame
{
public:
  NS_DECL_FRAMEARENA_HELPERS

  nsPositionedInlineFrame(nsStyleContext* aContext)
    : nsInlineFrame(aContext)
    , mAbsoluteContainer(nsGkAtoms::absoluteList)
  {}

  virtual ~nsPositionedInlineFrame() { } // useful for debugging

  virtual void DestroyFrom(nsIFrame* aDestructRoot);

  NS_IMETHOD SetInitialChildList(nsIAtom*        aListName,
                                 nsFrameList&    aChildList);
  NS_IMETHOD AppendFrames(nsIAtom*        aListName,
                          nsFrameList&    aFrameList);
  NS_IMETHOD InsertFrames(nsIAtom*        aListName,
                          nsIFrame*       aPrevFrame,
                          nsFrameList&    aFrameList);
  NS_IMETHOD RemoveFrame(nsIAtom*        aListName,
                         nsIFrame*       aOldFrame);

  NS_IMETHOD BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                              const nsRect&           aDirtyRect,
                              const nsDisplayListSet& aLists);

  virtual nsIAtom* GetAdditionalChildListName(PRInt32 aIndex) const;

  virtual nsFrameList GetChildList(nsIAtom* aListName) const;

  NS_IMETHOD Reflow(nsPresContext*          aPresContext,
                    nsHTMLReflowMetrics&     aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus&          aStatus);
  
  virtual nsIAtom* GetType() const;

  virtual PRBool NeedsView() { return PR_TRUE; }

protected:
  nsAbsoluteContainingBlock mAbsoluteContainer;
};

#endif /* nsInlineFrame_h___ */