gecko-dev/layout/base/nsBidiPresUtils.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* 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.org code.
*
* The Initial Developer of the Original Code is
* IBM Corporation. Portions created by IBM are
* Copyright (C) 2000 IBM Corporation. All
* Rights Reserved.
*
* Contributor(s):
*
*/
#ifdef IBMBIDI
#ifndef nsBidiPresUtils_h___
#define nsBidiPresUtils_h___
#include "nsVoidArray.h"
#include "nsIFrame.h"
#include "nsBidi.h"
#include "nsBidiUtils.h"
#include "nsCOMPtr.h"
#include "nsDataHashtable.h"
class nsBidiPresUtils {
public:
nsBidiPresUtils();
~nsBidiPresUtils();
PRBool IsSuccessful(void) const;
/**
* Make Bidi engine calculate the embedding levels of the frames that are
* descendants of a given block frame.
*
* @param aPresContext The presContext
* @param aBlockFrame The block frame
* @param aFirstChild The first child frame of aBlockFrame
* @param aForceReflow [OUT] Set if we delete frames and will need to
* reflow the block frame
* @param aIsVisualFormControl [IN] Set if we are in a form control on a
* visual page.
* @see nsHTMLReflowState::IsBidiFormControl
*
* @lina 06/18/2000
*/
nsresult Resolve(nsIPresContext* aPresContext,
nsIFrame* aBlockFrame,
nsIFrame* aFirstChild,
PRBool& aForceReflow,
PRBool aIsVisualFormControl);
/**
* Reorder this line using Bidi engine.
* Update frame array, following the new visual sequence.
*
* @lina 05/02/2000
*/
void ReorderFrames(nsIPresContext* aPresContext,
nsIRenderingContext* aRendContext,
nsIFrame* aFirstChild,
nsIFrame* aNextInFlow,
PRInt32 aChildCount);
/**
* Format Unicode text, taking into account bidi capabilities
* of the platform. The formatting includes: reordering, Arabic shaping,
* symmetric and numeric swapping, removing control characters.
*
* @lina 06/18/2000
*/
nsresult FormatUnicodeText(nsIPresContext* aPresContext,
PRUnichar* aText,
PRInt32& aTextLength,
nsCharType aCharType,
PRBool aIsOddLevel,
PRBool aIsBidiSystem);
/**
* Reorder Unicode text, taking into account bidi capabilities of the
* platform. The reordering includes symmetric swapping and removing
* control characters.
*/
nsresult ReorderUnicodeText(PRUnichar* aText,
PRInt32& aTextLength,
nsCharType aCharType,
PRBool aIsOddLevel,
PRBool aIsBidiSystem);
/**
* Return our nsBidi object (bidi reordering engine)
*/
nsresult GetBidiEngine(nsBidi** aBidiEngine);
/**
* Reorder plain text using the Unicode Bidi algorithm and send it to
* a rendering context for rendering.
*
* @param aText the string to be rendered
* @param aLength the number of characters in the string
* @param aBaseDirection the base direction of the string
* NSBIDI_LTR - left-to-right string
* NSBIDI_RTL - right-to-left string
* @param aPresContext the presentation context
* @param aRenderingContext the rendering context
* @param aTextRect contains the coordinates to render the string
*/
nsresult RenderText(PRUnichar* aText,
PRInt32 aLength,
nsBidiDirection aBaseDirection,
nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nscoord aX,
nscoord aY);
private:
/**
* Create a string containing entire text content of this block.
*
* @lina 05/02/2000
*/
void CreateBlockBuffer(nsIPresContext* aPresContext);
/**
* Set up an array of the frames after splitting frames so that each frame has
* consistent directionality. At this point the frames are still in logical
* order
*/
nsresult InitLogicalArray(nsIPresContext* aPresContext,
nsIFrame* aCurrentFrame,
nsIFrame* aNextInFlow,
PRBool aAddMarkers = PR_FALSE);
/**
* Reorder the frame array from logical to visual order
*
* @param aPresContext the presentation context
* @param aBidiEnabled TRUE on return if the visual order is different from
* the logical order
*/
nsresult Reorder(nsIPresContext* aPresContext,
PRBool& aBidiEnabled);
/**
* Adjust frame positions following their visual order
*
* @param <code>nsIPresContext*</code>, the first kid
*
* @lina 04/11/2000
*/
void RepositionInlineFrames(nsIPresContext* aPresContext,
nsIRenderingContext* aRendContext,
nsIFrame* aFirstChild,
PRInt32 aChildCount) const;
void RepositionContainerFrame(nsIPresContext* aPresContext,
nsIFrame* aContainer,
PRInt32& aMinX,
PRInt32& aMaxX) const;
/**
* Helper method for Resolve()
* Truncate a text frame and possibly create a continuation frame with the
* remainder of its content.
*
* @param aPresContext the pres context
* @param aContent the content of the frame
* @param aFrame the original frame
* @param aNewFrame [OUT] the new frame that was created
* @param aFrameIndex [IN/OUT] index of aFrame in mLogicalFrames
*
* If there is already a bidi continuation for this frame in mLogicalFrames,
* no new frame will be created. On exit aNewFrame will point to the existing
* bidi continuation and aFrameIndex will contain its index.
* @see Resolve()
* @see RemoveBidiContinuation()
*/
PRBool EnsureBidiContinuation(nsIPresContext* aPresContext,
nsIContent* aContent,
nsIFrame* aFrame,
nsIFrame** aNewFrame,
PRInt32& aFrameIndex);
/**
* Helper method for Resolve()
* Delete one or more bidi continuation frames created in a previous reflow by
* EnsureBidiContinuation().
* @param aPresContext the pres context
* @param aFrame the frame whose continuations are to be removed
* @param aFirstIndex index of aFrame in mLogicalFrames
* @param aLastIndex index of the last frame to be removed
* @param aOffset [OUT] count of directional frames removed. Since
* directional frames have control characters
* corresponding to them in mBuffer, the pointers to
* mBuffer in Resolve() will need to be updated after
* deleting the frames.
*
* @see Resolve()
* @see EnsureBidiContinuation()
*/
void RemoveBidiContinuation(nsIPresContext* aPresContext,
nsIFrame* aFrame,
PRInt32 aFirstIndex,
PRInt32 aLastIndex,
PRInt32& aOffset) const;
void CalculateCharType(PRInt32& aOffset,
PRInt32 aCharTypeLimit,
PRInt32& aRunLimit,
PRInt32& aRunLength,
PRInt32& aRunCount,
PRUint8& aCharType,
PRUint8& aPrevCharType) const;
void StripBidiControlCharacters(PRUnichar* aText,
PRInt32& aTextLength) const;
nsAutoString mBuffer;
nsVoidArray mLogicalFrames;
nsVoidArray mVisualFrames;
nsDataHashtable<nsISupportsHashKey, PRInt32> mContentToFrameIndex;
PRInt32 mArraySize;
PRInt32* mIndexMap;
PRUint8* mLevels;
nsresult mSuccess;
nsBidi* mBidiEngine;
};
#endif /* nsBidiPresUtils_h___ */
#endif // IBMBIDI