gecko-dev/layout/generic/nsSelection.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * Version: NPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.1 (the "License"); you may not use this file except in
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 *
 * 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 
 * 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 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"),
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 * ***** END LICENSE BLOCK ***** */

/*
 * Implementation of selection: nsISelection,nsISelectionPrivate and nsIFrameSelection
 */

#include "nsCOMPtr.h"
#include "nsWeakReference.h"
#include "nsIFactory.h"
#include "nsIEnumerator.h"
#include "nsString.h"
#include "nsReadableUtils.h"
#include "nsIDOMRange.h"
#include "nsIFrameSelection.h"
#include "nsISelection.h"
#include "nsISelectionPrivate.h"
#include "nsISelectionListener.h"
#include "nsIFocusTracker.h"
#include "nsIComponentManager.h"
#include "nsContentCID.h"
#include "nsIContent.h"
#include "nsIDOMElement.h"
#include "nsIDOMNode.h"
#include "nsRange.h"
#include "nsCOMArray.h"
#include "nsGUIEvent.h"
#include "nsIDOMKeyEvent.h"
#include "nsITableLayout.h"
#include "nsITableCellLayout.h"
#include "nsIDOMNodeList.h"
#include "nsITextContent.h"

#include "nsISelectionListener.h"
#include "nsIContentIterator.h"
#include "nsIDocumentEncoder.h"
#include "nsIPrefBranch.h"
#include "nsIPrefService.h"

// for IBMBIDI
#include "nsFrameTraversal.h"
#include "nsILineIterator.h"
#include "nsLayoutAtoms.h"
#include "nsIFrameTraversal.h"
#include "nsLayoutCID.h"
static NS_DEFINE_CID(kFrameTraversalCID, NS_FRAMETRAVERSAL_CID);

#include "nsIDOMText.h"

#include "nsContentUtils.h"

//included for desired x position;
#include "nsIPresContext.h"
#include "nsIPresShell.h"
#include "nsICaret.h"


// included for view scrolling
#include "nsIViewManager.h"
#include "nsIScrollableView.h"
#include "nsIDeviceContext.h"
#include "nsITimer.h"
#include "nsIServiceManager.h"
#include "nsIAutoCopy.h"
#include "nsIEventQueue.h"
#include "nsIEventQueueService.h"

// notifications
#include "nsIDOMDocument.h"
#include "nsIDocument.h"

#include "nsISelectionController.h"//for the enums
#include "nsHTMLAtoms.h"

#define STATUS_CHECK_RETURN_MACRO() {if (!mTracker) return NS_ERROR_FAILURE;}



//#define DEBUG_TABLE 1

// Selection's use of generated content iterators has been turned off
// temporarily since it bogs down selection in large documents. Using
// generated content iterators is slower because it must resolve the style
// for the content to find out if it has any before/after style, and it
// increases the number of calls to GetPrimaryFrame() which is very expensive.
//
// We can reduce the number of calls to GetPrimaryFrame() during selection
// by a good factor (maybe 2-3 times) if we just ignore the generated content
// and NOT hilite it when we cross it.
//
// #1 the output system doesn't handle it right now anyway so selecting
//    has no REAL benefit to generated content.
// #2 there is no available way given to me by troy that can give back the
//    necessary data without a frame to work from.
#ifdef USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
static NS_DEFINE_IID(kCGenContentIteratorCID, NS_GENERATEDCONTENTITERATOR_CID);
static NS_DEFINE_IID(kCGenSubtreeIteratorCID, NS_GENERATEDSUBTREEITERATOR_CID);
#else
static NS_DEFINE_IID(kCContentIteratorCID, NS_CONTENTITERATOR_CID);
static NS_DEFINE_IID(kCSubtreeIteratorCID, NS_SUBTREEITERATOR_CID);
#endif // USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE

#undef OLD_SELECTION
#undef OLD_TABLE_SELECTION


//PROTOTYPES
class nsSelectionIterator;
class nsSelection;
class nsAutoScrollTimer;
struct nsScrollSelectionIntoViewEvent;

PRBool  IsValidSelectionPoint(nsSelection *aFrameSel, nsIContent *aContent);
PRBool  IsValidSelectionPoint(nsSelection *aFrameSel, nsIDOMNode *aDomNode);

static nsIAtom *GetTag(nsIDOMNode *aNode);
static nsresult ParentOffset(nsIDOMNode *aNode, nsIDOMNode **aParent, PRInt32 *aChildOffset);
static nsIDOMNode *GetCellParent(nsIDOMNode *aDomNode);


#ifdef PRINT_RANGE
static void printRange(nsIDOMRange *aDomRange);
#define DEBUG_OUT_RANGE(x)  printRange(x)
#else
#define DEBUG_OUT_RANGE(x)  
#endif //MOZ_DEBUG



//#define DEBUG_SELECTION // uncomment for printf describing every collapse and extend.
//#define DEBUG_NAVIGATION


//#define DEBUG_TABLE_SELECTION 1


struct CachedOffsetForFrame {
  CachedOffsetForFrame()
  : mCachedFrameOffset(0, 0) // nsPoint ctor
  , mLastCaretFrame(nsnull)
  , mLastContentOffset(0)
  , mCanCacheFrameOffset(PR_FALSE)
  {}

  nsPoint      mCachedFrameOffset;      // cached frame offset
  nsIFrame*    mLastCaretFrame;         // store the frame the caret was last drawn in.
  PRInt32      mLastContentOffset;      // store last content offset
  PRPackedBool mCanCacheFrameOffset;    // cached frame offset is valid?
};

class nsTypedSelection : public nsISelection,
                         public nsISelectionPrivate,
                         public nsSupportsWeakReference
{
public:
  nsTypedSelection();
  nsTypedSelection(nsSelection *aList);
  virtual ~nsTypedSelection();
  
  NS_DECL_ISUPPORTS
  NS_DECL_NSISELECTION
  NS_DECL_NSISELECTIONPRIVATE

  // utility methods for scrolling the selection into view
  nsresult      GetPresContext(nsIPresContext **aPresContext);
  nsresult      GetPresShell(nsIPresShell **aPresShell);
  nsresult      GetRootScrollableView(nsIScrollableView **aScrollableView);
  nsresult      GetFrameToScrolledViewOffsets(nsIScrollableView *aScrollableView, nsIFrame *aFrame, nscoord *aXOffset, nscoord *aYOffset);
  nsresult      GetPointFromOffset(nsIFrame *aFrame, PRInt32 aContentOffset, nsPoint *aPoint);
  nsresult      GetSelectionRegionRectAndScrollableView(SelectionRegion aRegion, nsRect *aRect, nsIScrollableView **aScrollableView);
  nsresult      ScrollRectIntoView(nsIScrollableView *aScrollableView, nsRect& aRect, PRIntn  aVPercent, PRIntn  aHPercent, PRBool aScrollParentViews);

  nsresult      PostScrollSelectionIntoViewEvent(SelectionRegion aRegion);
  NS_IMETHOD    ScrollIntoView(SelectionRegion aRegion=nsISelectionController::SELECTION_FOCUS_REGION, PRBool aIsSynchronous=PR_TRUE);
  nsresult      AddItem(nsIDOMRange *aRange);
  nsresult      RemoveItem(nsIDOMRange *aRange);

  nsresult      Clear(nsIPresContext* aPresContext);
  // methods for convenience. Note, these don't addref
  nsIDOMNode*  FetchAnchorNode();  //where did the selection begin
  PRInt32      FetchAnchorOffset();

  nsIDOMNode*  FetchOriginalAnchorNode();  //where did the ORIGINAL selection begin
  PRInt32      FetchOriginalAnchorOffset();

  nsIDOMNode*  FetchFocusNode();   //where is the carret
  PRInt32      FetchFocusOffset();

  nsIDOMNode*  FetchStartParent(nsIDOMRange *aRange);   //skip all the com stuff and give me the start/end
  PRInt32      FetchStartOffset(nsIDOMRange *aRange);
  nsIDOMNode*  FetchEndParent(nsIDOMRange *aRange);     //skip all the com stuff and give me the start/end
  PRInt32      FetchEndOffset(nsIDOMRange *aRange);

  nsDirection  GetDirection(){return mDirection;}
  void         SetDirection(nsDirection aDir){mDirection = aDir;}
  PRBool       GetTrueDirection() {return mTrueDirection;}
  void         SetTrueDirection(PRBool aBool){mTrueDirection = aBool;}
  NS_IMETHOD   CopyRangeToAnchorFocus(nsIDOMRange *aRange);
  

//  NS_IMETHOD   GetPrimaryFrameForRangeEndpoint(nsIDOMNode *aNode, PRInt32 aOffset, PRBool aIsEndNode, nsIFrame **aResultFrame);
  NS_IMETHOD   GetPrimaryFrameForAnchorNode(nsIFrame **aResultFrame);
  NS_IMETHOD   GetPrimaryFrameForFocusNode(nsIFrame **aResultFrame, PRInt32 *aOffset);
  NS_IMETHOD   SetOriginalAnchorPoint(nsIDOMNode *aNode, PRInt32 aOffset);
  NS_IMETHOD   GetOriginalAnchorPoint(nsIDOMNode **aNode, PRInt32 *aOffset);
  NS_IMETHOD   LookUpSelection(nsIContent *aContent, PRInt32 aContentOffset, PRInt32 aContentLength,
                             SelectionDetails **aReturnDetails, SelectionType aType, PRBool aSlowCheck);
  NS_IMETHOD   Repaint(nsIPresContext* aPresContext);

  nsresult     StartAutoScrollTimer(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint, PRUint32 aDelay);
  nsresult     StopAutoScrollTimer();
  nsresult     DoAutoScroll(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint);
  nsresult     DoAutoScrollView(nsIPresContext *aPresContext, nsIView *aView, nsPoint& aPoint, PRBool aScrollParentViews);
  nsresult     ScrollPointIntoClipView(nsIPresContext *aPresContext, nsIView *aView, nsPoint& aPoint, PRBool *aDidScroll);
  nsresult     ScrollPointIntoView(nsIPresContext *aPresContext, nsIView *aView, nsPoint& aPoint, PRBool aScrollParentViews, PRBool *aDidScroll);
  nsresult     GetViewAncestorOffset(nsIView *aView, nsIView *aAncestorView, nscoord *aXOffset, nscoord *aYOffset);
  nsresult     GetClosestScrollableView(nsIView *aView, nsIScrollableView **aScrollableView);

  SelectionType GetType(){return mType;}
  void          SetType(SelectionType aType){mType = aType;}

  nsresult     NotifySelectionListeners();

private:
  friend class nsSelectionIterator;
  friend struct nsScrollSelectionIntoViewEvent;


  void         setAnchorFocusRange(PRInt32 aIndex); //pass in index into FrameSelection
  NS_IMETHOD   selectFrames(nsIPresContext* aPresContext, nsIContentIterator *aInnerIter, nsIContent *aContent, nsIDOMRange *aRange, nsIPresShell *aPresShell, PRBool aFlags);
  NS_IMETHOD   selectFrames(nsIPresContext* aPresContext, nsIDOMRange *aRange, PRBool aSelect);
  nsresult     getTableCellLocationFromRange(nsIDOMRange *aRange, PRInt32 *aSelectionType, PRInt32 *aRow, PRInt32 *aCol);
  nsresult     addTableCellRange(nsIDOMRange *aRange, PRBool *aDidAddRange);
  
#ifdef OLD_SELECTION
  NS_IMETHOD   FixupSelectionPoints(nsIDOMRange *aRange, nsDirection *aDir, PRBool *aFixupState);
#endif //OLD_SELECTION

  nsCOMArray<nsIDOMRange> mRangeArray;

  nsCOMPtr<nsIDOMRange> mAnchorFocusRange;
  nsCOMPtr<nsIDOMRange> mOriginalAnchorRange; //used as a point with range gravity for security
  nsDirection mDirection; //FALSE = focus, anchor;  TRUE = anchor, focus
  PRBool mFixupState; //was there a fixup?

  nsSelection *mFrameSelection;
  nsWeakPtr mPresShellWeak; //weak reference to presshell.
  SelectionType mType;//type of this nsTypedSelection;
  nsAutoScrollTimer *mAutoScrollTimer; // timer for autoscrolling.
  nsCOMArray<nsISelectionListener> mSelectionListeners;
  PRBool mTrueDirection;
  nsCOMPtr<nsIEventQueue> mEventQueue;
  PRBool mScrollEventPosted;
  CachedOffsetForFrame *mCachedOffsetForFrame;
};

// Stack-class to turn on/off selection batching for table selection
class nsSelectionBatcher
{
private:
  nsCOMPtr<nsISelectionPrivate> mSelection;
public:
  nsSelectionBatcher(nsISelectionPrivate *aSelection) : mSelection(aSelection)
  {
    if (mSelection) mSelection->StartBatchChanges();
  }
  virtual ~nsSelectionBatcher() 
  { 
    if (mSelection) mSelection->EndBatchChanges();
  }
};

class nsSelection : public nsIFrameSelection
                    
{
public:
  /*interfaces for addref and release and queryinterface*/
  
  NS_DECL_ISUPPORTS

/*BEGIN nsIFrameSelection interfaces*/
  NS_IMETHOD Init(nsIFocusTracker *aTracker, nsIContent *aLimiter);
  NS_IMETHOD SetScrollableView(nsIScrollableView *aScrollView);
  NS_IMETHOD GetScrollableView(nsIScrollableView **aScrollView) {*aScrollView = mScrollView; return NS_OK;}

  NS_IMETHOD ShutDown();
  NS_IMETHOD HandleTextEvent(nsGUIEvent *aGUIEvent);
  NS_IMETHOD HandleKeyEvent(nsIPresContext* aPresContext, nsGUIEvent *aGuiEvent);
  NS_IMETHOD HandleClick(nsIContent *aNewFocus, PRUint32 aContentOffset, PRUint32 aContentEndOffset, 
                       PRBool aContinueSelection, PRBool aMultipleSelection,PRBool aHint);
  NS_IMETHOD HandleDrag(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint);
  NS_IMETHOD HandleTableSelection(nsIContent *aParentContent, PRInt32 aContentOffset, PRInt32 aTarget, nsMouseEvent *aMouseEvent);
  NS_IMETHOD StartAutoScrollTimer(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint, PRUint32 aDelay);
  NS_IMETHOD StopAutoScrollTimer();
  NS_IMETHOD EnableFrameNotification(PRBool aEnable){mNotifyFrames = aEnable; return NS_OK;}
  NS_IMETHOD LookUpSelection(nsIContent *aContent, PRInt32 aContentOffset, PRInt32 aContentLength,
                             SelectionDetails **aReturnDetails, PRBool aSlowCheck);
  NS_IMETHOD SetMouseDownState(PRBool aState);
  NS_IMETHOD GetMouseDownState(PRBool *aState);

  NS_IMETHOD GetTableCellSelection(PRBool *aState){if (aState){*aState = mSelectingTableCellMode != 0; return NS_OK;}return NS_ERROR_NULL_POINTER;}
  NS_IMETHOD ClearTableCellSelection(){mSelectingTableCellMode = 0; return NS_OK;}
  
  NS_IMETHOD GetSelection(SelectionType aType, nsISelection **aDomSelection);
  NS_IMETHOD ScrollSelectionIntoView(SelectionType aType, SelectionRegion aRegion, PRBool aIsSynchronous);
  NS_IMETHOD RepaintSelection(nsIPresContext* aPresContext, SelectionType aType);
  NS_IMETHOD GetFrameForNodeOffset(nsIContent *aNode, PRInt32 aOffset, HINT aHint, nsIFrame **aReturnFrame, PRInt32 *aReturnOffset);
  NS_IMETHOD CommonPageMove(PRBool aForward, PRBool aExtend, nsIScrollableView *aScrollableView, nsIFrameSelection *aFrameSel);

  NS_IMETHOD AdjustOffsetsFromStyle(nsIFrame *aFrame, PRBool *changeSelection,
        nsIContent** outContent, PRInt32* outStartOffset, PRInt32* outEndOffset);
  
  NS_IMETHOD SetHint(HINT aHintRight);
  NS_IMETHOD GetHint(HINT *aHintRight);
  NS_IMETHOD CharacterMove(PRBool aForward, PRBool aExtend);
  NS_IMETHOD WordMove(PRBool aForward, PRBool aExtend);
  NS_IMETHOD LineMove(PRBool aForward, PRBool aExtend);
  NS_IMETHOD IntraLineMove(PRBool aForward, PRBool aExtend); 
  NS_IMETHOD SelectAll();
  NS_IMETHOD SetDisplaySelection(PRInt16 aState);
  NS_IMETHOD GetDisplaySelection(PRInt16 *aState);
  NS_IMETHOD SetDelayCaretOverExistingSelection(PRBool aDelay);
  NS_IMETHOD GetDelayCaretOverExistingSelection(PRBool *aDelay);
  NS_IMETHOD SetDelayedCaretData(nsMouseEvent *aMouseEvent);
  NS_IMETHOD GetDelayedCaretData(nsMouseEvent **aMouseEvent);
  NS_IMETHOD GetLimiter(nsIContent **aLimiterContent);
  NS_IMETHOD SetMouseDoubleDown(PRBool aDoubleDown);
  NS_IMETHOD GetMouseDoubleDown(PRBool *aDoubleDown);
  NS_IMETHOD GetPrevNextBidiLevels(nsIPresContext *aPresContext,
                                   nsIContent *aNode,
                                   PRUint32 aContentOffset,
                                   nsIFrame **aPrevFrame,
                                   nsIFrame **aNextFrame,
                                   PRUint8 *aPrevLevel,
                                   PRUint8 *aNextLevel);
  NS_IMETHOD GetFrameFromLevel(nsIPresContext *aPresContext,
                               nsIFrame *aFrameIn,
                               nsDirection aDirection,
                               PRUint8 aBidiLevel,
                               nsIFrame **aFrameOut);
  NS_IMETHOD MaintainSelection();
  /*END nsIFrameSelection interfaces */



  nsSelection();
  virtual ~nsSelection();

  NS_IMETHOD    StartBatchChanges();
  NS_IMETHOD    EndBatchChanges();
  NS_IMETHOD    DeleteFromDocument();

  nsIFocusTracker *GetTracker(){return mTracker;}

private:
  NS_IMETHOD TakeFocus(nsIContent *aNewFocus, PRUint32 aContentOffset, PRUint32 aContentEndOffset, 
                       PRBool aContinueSelection, PRBool aMultipleSelection);

  void BidiLevelFromMove(nsIPresContext* aContext,
                         nsIPresShell* aPresShell,
                         nsIContent *aNode,
                         PRUint32 aContentOffset,
                         PRUint32 aKeycode);
  void BidiLevelFromClick(nsIContent *aNewFocus, PRUint32 aContentOffset);
#ifdef VISUALSELECTION
  NS_IMETHOD VisualSelectFrames(nsIPresContext* aContext,
                                nsIFrame* aCurrentFrame,
                                nsPeekOffsetStruct aPos);
  NS_IMETHOD VisualSequence(nsIPresContext *aPresContext,
                            nsIFrame* aSelectFrame,
                            nsIFrame* aCurrentFrame,
                            nsPeekOffsetStruct* aPos,
                            PRBool* aNeedVisualSelection);
  NS_IMETHOD SelectToEdge(nsIFrame *aFrame,
                          nsIContent *aContent,
                          PRInt32 aOffset,
                          PRInt32 aEdge,
                          PRBool aMultipleSelection);
  NS_IMETHOD SelectLines(nsIPresContext *aPresContext,
                         nsDirection aSelectionDirection,
                         nsIDOMNode *aAnchorNode,
                         nsIFrame* aAnchorFrame,
                         PRInt32 aAnchorOffset,
                         nsIDOMNode *aCurrentNode,
                         nsIFrame* aCurrentFrame,
                         PRInt32 aCurrentOffset,
                         nsPeekOffsetStruct aPos);
#endif // VISUALSELECTION

  PRBool AdjustForMaintainedSelection(nsIContent *aContent, PRInt32 aOffset);

// post and pop reasons for notifications. we may stack these later
  void    PostReason(PRInt16 aReason) { mSelectionChangeReason = aReason; }
  PRInt16 PopReason()
  {
    PRInt16 retval = mSelectionChangeReason;
    mSelectionChangeReason = 0;
    return retval;
  }

  friend class nsTypedSelection; 
#ifdef DEBUG
  void printSelection();       // for debugging
#endif /* DEBUG */

  void ResizeBuffer(PRUint32 aNewBufSize);
/*HELPER METHODS*/
  nsresult     MoveCaret(PRUint32 aKeycode, PRBool aContinue, nsSelectionAmount aAmount);

  nsresult     FetchDesiredX(nscoord &aDesiredX); //the x position requested by the Key Handling for up down
  void         InvalidateDesiredX(); //do not listen to mDesiredX you must get another.
  void         SetDesiredX(nscoord aX); //set the mDesiredX

  nsresult     GetRootForContentSubtree(nsIContent *aContent, nsIContent **aParent);
  nsresult     GetGlobalViewOffsetsFromFrame(nsIPresContext *aPresContext, nsIFrame *aFrame, nscoord *offsetX, nscoord *offsetY);
  nsresult     ConstrainFrameAndPointToAnchorSubtree(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint, nsIFrame **aRetFrame, nsPoint& aRetPoint);

  PRUint32     GetBatching(){return mBatching;}
  PRBool       GetNotifyFrames(){return mNotifyFrames;}
  void         SetDirty(PRBool aDirty=PR_TRUE){if (mBatching) mChangesDuringBatching = aDirty;}

  nsresult     NotifySelectionListeners(SelectionType aType);     // add parameters to say collapsed etc?

  // utility method to lookup frame style
  nsresult      FrameOrParentHasSpecialSelectionStyle(nsIFrame* aFrame, PRUint8 aSelectionStyle, nsIFrame* *foundFrame);

  nsTypedSelection *mDomSelections[nsISelectionController::NUM_SELECTIONTYPES];

  // Table selection support.
  // Interfaces that let us get info based on cellmap locations
  nsITableLayout* GetTableLayout(nsIContent *aTableContent);
  nsITableCellLayout* GetCellLayout(nsIContent *aCellContent);

  nsresult SelectBlockOfCells(nsIContent *aStartNode, nsIContent *aEndNode);
  nsresult SelectRowOrColumn(nsIContent *aCellContent, PRUint32 aTarget);
  nsresult GetCellIndexes(nsIContent *aCell, PRInt32 &aRowIndex, PRInt32 &aColIndex);

  nsresult GetFirstSelectedCellAndRange(nsIDOMNode **aCell, nsIDOMRange **aRange);
  nsresult GetNextSelectedCellAndRange(nsIDOMNode **aCell, nsIDOMRange **aRange);
  nsresult GetFirstCellNodeInRange(nsIDOMRange *aRange, nsIDOMNode **aCellNode);
  // aTableNode may be null if table isn't needed to be returned
  PRBool   IsInSameTable(nsIContent *aContent1, nsIContent *aContent2, nsIContent **aTableNode);
  nsresult GetParentTable(nsIContent *aCellNode, nsIContent **aTableNode);
  nsresult SelectCellElement(nsIDOMElement* aCellElement);
  nsresult CreateAndAddRange(nsIDOMNode *aParentNode, PRInt32 aOffset);
  nsresult ClearNormalSelection();

  nsCOMPtr<nsIDOMNode> mCellParent; //used to snap to table selection
  nsCOMPtr<nsIContent> mStartSelectedCell;
  nsCOMPtr<nsIContent> mEndSelectedCell;
  nsCOMPtr<nsIContent> mAppendStartSelectedCell;
  nsCOMPtr<nsIContent> mUnselectCellOnMouseUp;
  PRInt32  mSelectingTableCellMode;
  PRInt32  mSelectedCellIndex;

  // maintain selection
  nsCOMPtr<nsIDOMRange> mMaintainRange;

  //batching
  PRInt32 mBatching;
    
  nsIContent *mLimiter;     //limit selection navigation to a child of this node.
  nsIFocusTracker *mTracker;

  PRInt16 mSelectionChangeReason; // reason for notifications of selection changing
  PRInt16 mDisplaySelection; //for visual display purposes.

  HINT  mHint;   //hint to tell if the selection is at the end of this line or beginning of next

  PRInt32 mDesiredX;
  nsIScrollableView *mScrollView;

  nsMouseEvent mDelayedMouseEvent;

  PRPackedBool mDelayCaretOverExistingSelection;
  PRPackedBool mDelayedMouseEventValid;

  PRPackedBool mChangesDuringBatching;
  PRPackedBool mNotifyFrames;
  PRPackedBool mIsEditor;
  PRPackedBool mDragSelectingCells;
  PRPackedBool mMouseDownState;   //for drag purposes
  PRPackedBool mMouseDoubleDownState; //has the doubleclick down happened
  PRPackedBool mDesiredXSet;
};

class nsSelectionIterator : public nsIBidirectionalEnumerator
{
public:
/*BEGIN nsIEnumerator interfaces
see the nsIEnumerator for more details*/

  NS_DECL_ISUPPORTS

  NS_DECL_NSIENUMERATOR

  NS_DECL_NSIBIDIRECTIONALENUMERATOR

/*END nsIEnumerator interfaces*/
/*BEGIN Helper Methods*/
  NS_IMETHOD CurrentItem(nsIDOMRange **aRange);
/*END Helper Methods*/
private:
  friend class nsTypedSelection;

  //lame lame lame if delete from document goes away then get rid of this unless its debug
  friend class nsSelection; 

  nsSelectionIterator(nsTypedSelection *);
  virtual ~nsSelectionIterator();
  PRInt32     mIndex;
  nsTypedSelection *mDomSelection;
  SelectionType mType;
};

class nsAutoScrollTimer : public nsITimerCallback
{
public:

  NS_DECL_ISUPPORTS

  nsAutoScrollTimer()
      : mSelection(0), mView(0), mPresContext(0), mPoint(0,0), mDelay(30)
  {
  }

  virtual ~nsAutoScrollTimer()
  {
   if (mTimer)
       mTimer->Cancel();
  }

  nsresult Start(nsIPresContext *aPresContext, nsIView *aView, nsPoint &aPoint)
  {
    mView        = aView;
    mPresContext = aPresContext;
    mPoint       = aPoint;

    if (!mTimer)
    {
      nsresult result;
      mTimer = do_CreateInstance("@mozilla.org/timer;1", &result);

      if (NS_FAILED(result))
        return result;
    }

    return mTimer->InitWithCallback(this, mDelay, nsITimer::TYPE_ONE_SHOT);
  }

  nsresult Stop()
  {
    nsresult result = NS_OK;

    if (mTimer)
    {
      mTimer->Cancel();
      mTimer = 0;
    }

    return result;
  }

  nsresult Init(nsSelection *aFrameSelection, nsTypedSelection *aSelection)
  {
    mFrameSelection = aFrameSelection;
    mSelection = aSelection;
    return NS_OK;
  }

  nsresult SetDelay(PRUint32 aDelay)
  {
    mDelay = aDelay;
    return NS_OK;
  }

  NS_IMETHOD Notify(nsITimer *timer)
  {
    if (mSelection && mPresContext && mView)
    {
      nsIFrame *frame = NS_STATIC_CAST(nsIFrame*, mView->GetClientData());

      if (!frame)
        return NS_OK;

      //the frame passed in here will be a root frame for the view. there is no need to call the constrain
      //method here. the root frame has NO content now unfortunately...
      PRInt32 startPos = 0;
      PRInt32 contentOffsetEnd = 0;
      PRBool  beginOfContent;
      nsCOMPtr<nsIContent> newContent;
      nsresult result = frame->GetContentAndOffsetsFromPoint(mPresContext, mPoint,
                                                   getter_AddRefs(newContent), 
                                                   startPos, contentOffsetEnd,beginOfContent);

      if (NS_SUCCEEDED(result))
        result = mFrameSelection->HandleClick(newContent, startPos, contentOffsetEnd , PR_TRUE, PR_FALSE, beginOfContent);

      //mFrameSelection->HandleDrag(mPresContext, mFrame, mPoint);
      mSelection->DoAutoScrollView(mPresContext, mView, mPoint, PR_TRUE);
    }
    return NS_OK;
  }
private:
  nsSelection    *mFrameSelection;
  nsTypedSelection *mSelection;
  nsCOMPtr<nsITimer> mTimer;
  nsIView        *mView;
  nsIPresContext *mPresContext;
  nsPoint         mPoint;
  PRUint32        mDelay;
};

NS_IMPL_ADDREF(nsAutoScrollTimer)
NS_IMPL_RELEASE(nsAutoScrollTimer)
NS_IMPL_QUERY_INTERFACE1(nsAutoScrollTimer, nsITimerCallback)

nsresult NS_NewAutoScrollTimer(nsAutoScrollTimer **aResult);

nsresult NS_NewAutoScrollTimer(nsAutoScrollTimer **aResult)
{
  if (!aResult)
    return NS_ERROR_NULL_POINTER;

  *aResult = (nsAutoScrollTimer*) new nsAutoScrollTimer;

  if (!aResult)
    return NS_ERROR_OUT_OF_MEMORY;

  NS_ADDREF(*aResult);

  return NS_OK;
}

nsresult NS_NewSelection(nsIFrameSelection **aFrameSelection);

nsresult NS_NewSelection(nsIFrameSelection **aFrameSelection)
{
  nsSelection *rlist = new nsSelection;
  if (!rlist)
    return NS_ERROR_OUT_OF_MEMORY;
  *aFrameSelection = (nsIFrameSelection *)rlist;
  rlist->AddRef();
  return NS_OK;
}

nsresult NS_NewDomSelection(nsISelection **aDomSelection);

nsresult NS_NewDomSelection(nsISelection **aDomSelection)
{
  nsTypedSelection *rlist = new nsTypedSelection;
  if (!rlist)
    return NS_ERROR_OUT_OF_MEMORY;
  *aDomSelection = (nsISelection *)rlist;
  rlist->AddRef();
  return NS_OK;
}

static PRInt8
GetIndexFromSelectionType(SelectionType aType)
{
    switch (aType)
    {
    case nsISelectionController::SELECTION_NORMAL: return 0; break;
    case nsISelectionController::SELECTION_SPELLCHECK: return 1; break;
    case nsISelectionController::SELECTION_IME_RAWINPUT: return 2; break;
    case nsISelectionController::SELECTION_IME_SELECTEDRAWTEXT: return 3; break;
    case nsISelectionController::SELECTION_IME_CONVERTEDTEXT: return 4; break;
    case nsISelectionController::SELECTION_IME_SELECTEDCONVERTEDTEXT: return 5; break;
    case nsISelectionController::SELECTION_ACCESSIBILITY: return 6; break;
    default:return -1;break;
    }
    /* NOTREACHED */
    return 0;
}

static SelectionType 
GetSelectionTypeFromIndex(PRInt8 aIndex)
{
  switch (aIndex)
  {
    case 0: return nsISelectionController::SELECTION_NORMAL;break;
    case 1: return nsISelectionController::SELECTION_SPELLCHECK;break;
    case 2: return nsISelectionController::SELECTION_IME_RAWINPUT;break;
    case 3: return nsISelectionController::SELECTION_IME_SELECTEDRAWTEXT;break;
    case 4: return nsISelectionController::SELECTION_IME_CONVERTEDTEXT;break;
    case 5: return nsISelectionController::SELECTION_IME_SELECTEDCONVERTEDTEXT;break;
    case 6: return nsISelectionController::SELECTION_ACCESSIBILITY;break;
    default:
      return nsISelectionController::SELECTION_NORMAL;break;
  }
  /* NOTREACHED */
  return 0;
}

//utility methods to check the content vs the limiter that will hold selection to a piece of the dom
PRBool       
IsValidSelectionPoint(nsSelection *aFrameSel, nsIDOMNode *aDomNode)
{
    nsCOMPtr<nsIContent> passedContent;
    passedContent = do_QueryInterface(aDomNode);
    if (!passedContent)
      return PR_FALSE;
    return IsValidSelectionPoint(aFrameSel,passedContent);
}

/*
The limiter is used specifically for the text areas and textfields
In that case it is the DIV tag that is anonymously created for the text
areas/fields.  Text nodes and BR nodes fall beneath it.  In the case of a 
BR node the limiter will be the parent and the offset will point before or
after the BR node.  In the case of the text node the parent content is 
the text node itself and the offset will be the exact character position.
The offset is not important to check for validity.  Simply look at the 
passed in content.  If it equals the limiter then the selection point is valid.
If its parent it the limiter then the point is also valid.  In the case of 
NO limiter all points are valid since you are in a topmost iframe. (browser
or composer)
*/
PRBool       
IsValidSelectionPoint(nsSelection *aFrameSel, nsIContent *aContent)
{
  if (!aFrameSel || !aContent)
    return PR_FALSE;
  if (aFrameSel)
  {
    nsresult result;
    nsCOMPtr<nsIContent> tLimiter;
    result = aFrameSel->GetLimiter(getter_AddRefs(tLimiter));
    if (NS_FAILED(result))
      return PR_FALSE;
    if (tLimiter && tLimiter != aContent)
    {
      if (tLimiter != aContent->GetParent()) //if newfocus == the limiter. thats ok. but if not there and not parent bad
        return PR_FALSE; //not in the right content. tLimiter said so
    }
  }
  return PR_TRUE;
}


NS_IMPL_ADDREF(nsSelectionIterator)
NS_IMPL_RELEASE(nsSelectionIterator)

NS_INTERFACE_MAP_BEGIN(nsSelectionIterator)
  NS_INTERFACE_MAP_ENTRY(nsIEnumerator)
  NS_INTERFACE_MAP_ENTRY(nsIBidirectionalEnumerator)
NS_INTERFACE_MAP_END_AGGREGATED(mDomSelection)


///////////BEGIN nsSelectionIterator methods

nsSelectionIterator::nsSelectionIterator(nsTypedSelection *aList)
:mIndex(0)
{
  if (!aList)
  {
    NS_NOTREACHED("nsSelection");
    return;
  }
  mDomSelection = aList;
}



nsSelectionIterator::~nsSelectionIterator()
{
}



////////////END nsSelectionIterator methods

////////////BEGIN nsIFrameSelectionIterator methods



NS_IMETHODIMP
nsSelectionIterator::Next()
{
  mIndex++;
  PRInt32 cnt = mDomSelection->mRangeArray.Count();
  if (mIndex < cnt)
    return NS_OK;
  return NS_ERROR_FAILURE;
}



NS_IMETHODIMP
nsSelectionIterator::Prev()
{
  mIndex--;
  if (mIndex >= 0 )
    return NS_OK;
  return NS_ERROR_FAILURE;
}



NS_IMETHODIMP
nsSelectionIterator::First()
{
  if (!mDomSelection)
    return NS_ERROR_NULL_POINTER;
  mIndex = 0;
  return NS_OK;
}



NS_IMETHODIMP
nsSelectionIterator::Last()
{
  if (!mDomSelection)
    return NS_ERROR_NULL_POINTER;
  mIndex = mDomSelection->mRangeArray.Count() - 1;
  return NS_OK;
}



NS_IMETHODIMP 
nsSelectionIterator::CurrentItem(nsISupports **aItem)
{
  if (!aItem)
    return NS_ERROR_NULL_POINTER;

  if (mIndex < 0 || mIndex >= mDomSelection->mRangeArray.Count()) {
    return NS_ERROR_FAILURE;
  }

  return CallQueryInterface(mDomSelection->mRangeArray[mIndex],
                            aItem);
}


NS_IMETHODIMP 
nsSelectionIterator::CurrentItem(nsIDOMRange **aItem)
{
  if (!aItem)
    return NS_ERROR_NULL_POINTER;
  if (mIndex < 0 || mIndex >= mDomSelection->mRangeArray.Count()) {
    return NS_ERROR_FAILURE;
  }

  *aItem = mDomSelection->mRangeArray[mIndex];
  NS_IF_ADDREF(*aItem);
  return NS_OK;
}



NS_IMETHODIMP
nsSelectionIterator::IsDone()
{
  PRInt32 cnt = mDomSelection->mRangeArray.Count();
  if (mIndex >= 0 && mIndex < cnt) {
    return NS_ENUMERATOR_FALSE;
  }
  return NS_OK;
}


////////////END nsIFrameSelectionIterator methods

#ifdef XP_MAC
#pragma mark -
#endif

////////////BEGIN nsSelection methods

nsSelection::nsSelection()
{
  PRInt32 i;
  for (i = 0;i<nsISelectionController::NUM_SELECTIONTYPES;i++){
    mDomSelections[i] = nsnull;
  }
  for (i = 0;i<nsISelectionController::NUM_SELECTIONTYPES;i++){
    mDomSelections[i] = new nsTypedSelection(this);
    if (!mDomSelections[i])
      return;
    mDomSelections[i]->AddRef();
    mDomSelections[i]->SetType(GetSelectionTypeFromIndex(i));
  }
  mBatching = 0;
  mChangesDuringBatching = PR_FALSE;
  mNotifyFrames = PR_TRUE;
  mLimiter = nsnull; //no default limiter.
  
  mMouseDoubleDownState = PR_FALSE;
  
  mHint = HINTLEFT;
  mDragSelectingCells = PR_FALSE;
  mSelectingTableCellMode = 0;
  mSelectedCellIndex = 0;


  
  // Check to see if the autocopy pref is enabled
  //   and add the autocopy listener if it is
  nsCOMPtr<nsIPrefBranch> prefBranch(do_GetService(NS_PREFSERVICE_CONTRACTID));
  if (prefBranch) {
    static char pref[] = "clipboard.autocopy";
    PRBool autoCopy = PR_FALSE;
    if (NS_SUCCEEDED(prefBranch->GetBoolPref(pref, &autoCopy)) && autoCopy) {
      nsCOMPtr<nsIAutoCopyService> autoCopyService = 
        do_GetService("@mozilla.org/autocopy;1");

      if (autoCopyService) {
        PRInt8 index =
          GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
        if (mDomSelections[index]) {
          autoCopyService->Listen(mDomSelections[index]);
        }
      }
    }
  }

  mDisplaySelection = nsISelectionController::SELECTION_OFF;

  mDelayCaretOverExistingSelection = PR_TRUE;
  mDelayedMouseEventValid = PR_FALSE;
  mSelectionChangeReason = nsISelectionListener::NO_REASON;
}


nsSelection::~nsSelection() 
{
  PRInt32 i;
  for (i = 0;i<nsISelectionController::NUM_SELECTIONTYPES;i++){
    if (mDomSelections[i])
        NS_IF_RELEASE(mDomSelections[i]);
  }
}


NS_IMPL_ISUPPORTS1(nsSelection, nsIFrameSelection)


nsresult
nsSelection::FetchDesiredX(nscoord &aDesiredX) //the x position requested by the Key Handling for up down
{
  if (!mTracker)
  {
    NS_ASSERTION(0,"fetch desired X failed\n");
    return NS_ERROR_FAILURE;
  }
  if (mDesiredXSet)
  {
    aDesiredX = mDesiredX;
    return NS_OK;
  }

  nsCOMPtr<nsIPresContext> context;
  nsresult result = mTracker->GetPresContext(getter_AddRefs(context));
  if (NS_FAILED(result))
    return result;
  if (!context)
    return NS_ERROR_NULL_POINTER;

  nsIPresShell *shell = context->GetPresShell();
  if (!shell)
    return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsICaret> caret;
  result = shell->GetCaret(getter_AddRefs(caret));
  if (NS_FAILED(result))
    return result;
  if (!caret)
    return NS_ERROR_NULL_POINTER;

  nsRect coord;
  PRBool  collapsed;
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  result = caret->SetCaretDOMSelection(mDomSelections[index]);
  if (NS_FAILED(result))
    return result;

  result = caret->GetCaretCoordinates(nsICaret::eClosestViewCoordinates, mDomSelections[index], &coord, &collapsed, nsnull);
  if (NS_FAILED(result))
    return result;
   
  aDesiredX = coord.x;
  return NS_OK;
}



void
nsSelection::InvalidateDesiredX() //do not listen to mDesiredX you must get another.
{
  mDesiredXSet = PR_FALSE;
}



void
nsSelection::SetDesiredX(nscoord aX) //set the mDesiredX
{
  mDesiredX = aX;
  mDesiredXSet = PR_TRUE;
}

nsresult
nsSelection::GetRootForContentSubtree(nsIContent *aContent, nsIContent **aParent)
{
  // This method returns the root of the sub-tree containing aContent.
  // We do this by searching up through the parent hierarchy, and stopping
  // when there are no more parents, or we hit a situation where the
  // parent/child relationship becomes invalid.
  //
  // An example of an invalid parent/child relationship is anonymous content.
  // Anonymous content has a pointer to it's parent, but it is not listed
  // as a child of it's parent. In this case, the anonymous content would
  // be considered the root of the subtree.

  if (!aContent || !aParent)
    return NS_ERROR_NULL_POINTER;

  *aParent = 0;

  nsIContent* child = aContent;

  while (child)
  {
    nsIContent* parent = child->GetParent();

    if (!parent)
      break;

    PRUint32 childCount = parent->GetChildCount();

    if (childCount < 1)
      break;

    PRInt32 childIndex = parent->IndexOf(child);

    if (childIndex < 0 || ((PRUint32)childIndex) >= childCount)
      break;

    child = parent;
  }

  NS_IF_ADDREF(*aParent = child);

  return NS_OK;
}

nsresult
nsSelection::GetGlobalViewOffsetsFromFrame(nsIPresContext *aPresContext, nsIFrame *aFrame, nscoord *offsetX, nscoord *offsetY)
{
  //
  // The idea here is to figure out what the offset of aFrame's view
  // is within the global space. Where I define the global space to
  // be the coordinate system that exists above all views.
  //
  // The offsets are calculated by walking up the view parent hierarchy,
  // adding up all the view positions, until there are no more views.
  //
  // A point in a view's coordinate space can be converted to the global
  // coordinate space by simply adding the offsets returned by this method
  // to the point itself.
  //

  if (!aPresContext || !aFrame || !offsetX || !offsetY)
    return NS_ERROR_NULL_POINTER;

  *offsetX = *offsetY = 0;

  nsIFrame *frame = aFrame;
  while (frame)
  {
    frame = frame->GetAncestorWithView();

    if (frame) {
      nsIView *view = frame->GetView();

      if (view)
      {
        nsPoint pt = view->GetPosition();
        *offsetX += pt.x;
        *offsetY += pt.y;
      }
    }
  }

  return NS_OK;
}

nsresult
nsSelection::ConstrainFrameAndPointToAnchorSubtree(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint, nsIFrame **aRetFrame, nsPoint& aRetPoint)
{
  //
  // The whole point of this method is to return a frame and point that
  // that lie within the same valid subtree as the anchor node's frame,
  // for use with the method GetContentAndOffsetsFromPoint().
  //
  // A valid subtree is defined to be one where all the content nodes in
  // the tree have a valid parent-child relationship.
  //
  // If the anchor frame and aFrame are in the same subtree, aFrame will
  // be returned in aRetFrame. If they are in different subtrees, we
  // return the frame for the root of the subtree.
  //

  if (!aFrame || !aRetFrame)
    return NS_ERROR_NULL_POINTER;

  *aRetFrame = aFrame;
  aRetPoint  = aPoint;

  //
  // Get the frame and content for the selection's anchor point!
  //

  nsresult result;
  nsCOMPtr<nsIDOMNode> anchorNode;
  PRInt32 anchorOffset = 0;
  PRInt32 anchorFrameOffset = 0;

  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  if (! mDomSelections[index])
    return NS_ERROR_NULL_POINTER;

  result = mDomSelections[index]->GetAnchorNode(getter_AddRefs(anchorNode));

  if (NS_FAILED(result))
    return result;

  if (!anchorNode)
    return NS_OK;

  result = mDomSelections[index]->GetAnchorOffset(&anchorOffset);

  if (NS_FAILED(result))
    return result;

  nsIFrame *anchorFrame = 0;
  nsCOMPtr<nsIContent> anchorContent = do_QueryInterface(anchorNode);

  if (!anchorContent)
    return NS_ERROR_FAILURE;
  
  result = GetFrameForNodeOffset(anchorContent, anchorOffset, mHint, &anchorFrame, &anchorFrameOffset);

  //
  // Now find the root of the subtree containing the anchor's content.
  //

  nsCOMPtr<nsIContent> anchorRoot;
  result = GetRootForContentSubtree(anchorContent, getter_AddRefs(anchorRoot));

  if (NS_FAILED(result))
    return result;

  //
  // Now find the root of the subtree containing aFrame's content.
  //

  nsIContent* content = aFrame->GetContent();

  if (content)
  {
    nsCOMPtr<nsIContent> contentRoot;

    result = GetRootForContentSubtree(content, getter_AddRefs(contentRoot));

    if (anchorRoot == contentRoot)
    {
      //
      // The anchor and AFrame's root are the same. There
      // is no need to constrain, simply return aFrame.
      //
      *aRetFrame = aFrame;
      return NS_OK;
    }
  }

  //
  // aFrame's root does not match the anchor's root, or there is no
  // content associated with aFrame. Just return the primary frame
  // for the anchor's root. We'll let GetContentAndOffsetsFromPoint()
  // find the closest frame aPoint.
  //

  result = mTracker->GetPrimaryFrameFor(anchorRoot, aRetFrame);

  if (NS_FAILED(result))
    return result;

  if (! *aRetFrame)
    return NS_ERROR_FAILURE;

  //
  // Now make sure that aRetPoint is converted to the same coordinate
  // system used by aRetFrame.
  //

  nsPoint frameOffset;
  nsPoint retFrameOffset;

  result = GetGlobalViewOffsetsFromFrame(aPresContext, aFrame, &frameOffset.x, &frameOffset.y);

  if (NS_FAILED(result))
    return result;

  result = GetGlobalViewOffsetsFromFrame(aPresContext, *aRetFrame, &retFrameOffset.x, &retFrameOffset.y);

  if (NS_FAILED(result))
    return result;

  aRetPoint = aPoint + frameOffset - retFrameOffset;

  return NS_OK;
}

#ifdef XP_MAC
#pragma mark -
#endif

#ifdef PRINT_RANGE
void printRange(nsIDOMRange *aDomRange)
{
  if (!aDomRange)
  {
    printf("NULL nsIDOMRange\n");
  }
  nsCOMPtr<nsIDOMNode> startNode;
  nsCOMPtr<nsIDOMNode> endNode;
  PRInt32 startOffset;
  PRInt32 endOffset;
  aDomRange->GetStartParent(getter_AddRefs(startNode));
  aDomRange->GetStartOffset(&startOffset);
  aDomRange->GetEndParent(getter_AddRefs(endNode));
  aDomRange->GetEndOffset(&endOffset);
  
  printf("range: 0x%lx\t start: 0x%lx %ld, \t end: 0x%lx,%ld\n",
         (unsigned long)aDomRange,
         (unsigned long)(nsIDOMNode*)startNode, (long)startOffset,
         (unsigned long)(nsIDOMNode*)endNode, (long)endOffset);
         
}
#endif /* PRINT_RANGE */

static
nsIAtom *GetTag(nsIDOMNode *aNode)
{
  nsCOMPtr<nsIContent> content = do_QueryInterface(aNode);
  if (!content) 
  {
    NS_NOTREACHED("bad node passed to GetTag()");
    return nsnull;
  }
  
  return content->Tag();
}

nsresult
ParentOffset(nsIDOMNode *aNode, nsIDOMNode **aParent, PRInt32 *aChildOffset)
{
  if (!aNode || !aParent || !aChildOffset)
    return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsIContent> content = do_QueryInterface(aNode);
  if (content)
  {
    nsIContent* parent = content->GetParent();
    if (parent)
    {
      *aChildOffset = parent->IndexOf(content);

      return CallQueryInterface(parent, aParent);
    }
  }

  return NS_OK;
}

nsIDOMNode *
GetCellParent(nsIDOMNode *aDomNode)
{
    if (!aDomNode)
      return 0;
    nsCOMPtr<nsIDOMNode> parent(aDomNode);
    nsCOMPtr<nsIDOMNode> current(aDomNode);
    PRInt32 childOffset;
    nsIAtom *tag;
    // Start with current node and look for a table cell
    while(current)
    {
      tag = GetTag(current);
      if (tag == nsHTMLAtoms::td)
        return current;
      if (NS_FAILED(ParentOffset(current,getter_AddRefs(parent),&childOffset)) || !parent)
        return 0;
      current = parent;
    }
    return 0;
}


NS_IMETHODIMP
nsSelection::Init(nsIFocusTracker *aTracker, nsIContent *aLimiter)
{
  mTracker = aTracker;
  mMouseDownState = PR_FALSE;
  mDesiredXSet = PR_FALSE;
  mLimiter = aLimiter;
  mScrollView = nsnull;
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::SetScrollableView(nsIScrollableView *aScrollView)
{
  mScrollView = aScrollView;
  return NS_OK;
}


NS_IMETHODIMP
nsSelection::ShutDown()
{
  return NS_OK;
}

  
  
NS_IMETHODIMP
nsSelection::HandleTextEvent(nsGUIEvent *aGUIEvent)
{
  if (!aGUIEvent)
    return NS_ERROR_NULL_POINTER;

#ifdef DEBUG_TAGUE
  printf("nsSelection: HandleTextEvent\n");
#endif
  nsresult result(NS_OK);
  if (NS_TEXT_TEXT == aGUIEvent->message) {
    PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
    result = mDomSelections[index]->ScrollIntoView();
  }
  return result;
}


nsresult
nsSelection::MoveCaret(PRUint32 aKeycode, PRBool aContinue, nsSelectionAmount aAmount)
{
  nsCOMPtr<nsIPresContext> context;
  nsresult result = mTracker->GetPresContext(getter_AddRefs(context));
  if (NS_FAILED(result) || !context)
    return result?result:NS_ERROR_FAILURE;

  nsCOMPtr<nsIDOMNode> weakNodeUsed;
  PRInt32 offsetused = 0;

  PRBool isCollapsed;
  nscoord desiredX = 0; //we must keep this around and revalidate it when its just UP/DOWN

  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  result = mDomSelections[index]->GetIsCollapsed(&isCollapsed);
  if (NS_FAILED(result))
    return result;
  if (aKeycode == nsIDOMKeyEvent::DOM_VK_UP || aKeycode == nsIDOMKeyEvent::DOM_VK_DOWN)
  {
    result = FetchDesiredX(desiredX);
    if (NS_FAILED(result))
      return result;
    SetDesiredX(desiredX);
  }

  if (!isCollapsed && !aContinue) {
    switch (aKeycode){
      case nsIDOMKeyEvent::DOM_VK_LEFT  : 
      case nsIDOMKeyEvent::DOM_VK_UP    : {
          if ((mDomSelections[index]->GetDirection() == eDirPrevious)) { //f,a
            offsetused = mDomSelections[index]->FetchFocusOffset();
            weakNodeUsed = mDomSelections[index]->FetchFocusNode();
          }
          else {
            offsetused = mDomSelections[index]->FetchAnchorOffset();
            weakNodeUsed = mDomSelections[index]->FetchAnchorNode();
          }
          result = mDomSelections[index]->Collapse(weakNodeUsed,offsetused);
          mDomSelections[index]->ScrollIntoView();
          mHint = HINTRIGHT;
          return NS_OK;
         } break;
      case nsIDOMKeyEvent::DOM_VK_RIGHT : 
      case nsIDOMKeyEvent::DOM_VK_DOWN  : {
          if ((mDomSelections[index]->GetDirection() == eDirPrevious)) { //f,a
            offsetused = mDomSelections[index]->FetchAnchorOffset();
            weakNodeUsed = mDomSelections[index]->FetchAnchorNode();
          }
          else {
            offsetused = mDomSelections[index]->FetchFocusOffset();
            weakNodeUsed = mDomSelections[index]->FetchFocusNode();
          }
          result = mDomSelections[index]->Collapse(weakNodeUsed,offsetused);
          mDomSelections[index]->ScrollIntoView();
          mHint = HINTLEFT;
          return NS_OK;
         } break;
      
    }
//      if (keyEvent->keyCode == nsIDOMKeyEvent::DOM_VK_UP || keyEvent->keyCode == nsIDOMKeyEvent::DOM_VK_DOWN)
//        SetDesiredX(desiredX);
  }

  nsCOMPtr<nsICaret> caret;
  nsIPresShell *shell = context->GetPresShell();
  if (!shell)
    return 0;
  result = shell->GetCaret(getter_AddRefs(caret));
  if (NS_FAILED(result) || !caret)
    return 0;

  offsetused = mDomSelections[index]->FetchFocusOffset();
  weakNodeUsed = mDomSelections[index]->FetchFocusNode();

    
  nsIFrame *frame;
  result = mDomSelections[index]->GetPrimaryFrameForFocusNode(&frame, &offsetused);

  if (NS_FAILED(result) || !frame)
    return result?result:NS_ERROR_FAILURE;
  nsCOMPtr<nsIDOMNode> node = do_QueryInterface(frame->GetContent());
  nsCOMPtr<nsIDOMNode> parentNode;
  nsPeekOffsetStruct pos;

  //set data using mLimiter to stop on scroll views.  If we have a limiter then we stop peeking
  //when we hit scrollable views.  If no limiter then just let it go ahead
  pos.SetData(mTracker, desiredX, aAmount, eDirPrevious, offsetused, PR_FALSE,
              PR_TRUE, PR_TRUE, mLimiter != nsnull, PR_TRUE);

  HINT tHint(mHint); //temporary variable so we dont set mHint until it is necessary
  switch (aKeycode){
    case nsIDOMKeyEvent::DOM_VK_RIGHT : 
        InvalidateDesiredX();
        pos.mDirection = eDirNext;
        tHint = HINTLEFT;//stick to this line
        PostReason(nsISelectionListener::KEYPRESS_REASON);
      break;
    case nsIDOMKeyEvent::DOM_VK_LEFT  : //no break
        InvalidateDesiredX();
        tHint = HINTRIGHT;//stick to opposite of movement
        PostReason(nsISelectionListener::KEYPRESS_REASON);
      break;
    case nsIDOMKeyEvent::DOM_VK_DOWN : 
        pos.mAmount = eSelectLine;
        pos.mDirection = eDirNext;//no break here
        PostReason(nsISelectionListener::KEYPRESS_REASON);
      break;
    case nsIDOMKeyEvent::DOM_VK_UP : 
        pos.mAmount = eSelectLine;
        PostReason(nsISelectionListener::KEYPRESS_REASON);
      break;
    case nsIDOMKeyEvent::DOM_VK_HOME :
        InvalidateDesiredX();
        pos.mAmount = eSelectBeginLine;
        tHint = HINTRIGHT;//stick to opposite of movement
        PostReason(nsISelectionListener::KEYPRESS_REASON);
      break;
    case nsIDOMKeyEvent::DOM_VK_END :
        InvalidateDesiredX();
        pos.mAmount = eSelectEndLine;
        tHint = HINTLEFT;//stick to this line
        PostReason(nsISelectionListener::KEYPRESS_REASON);
     break;
  default :return NS_ERROR_FAILURE;
  }
  pos.mPreferLeft = tHint;
  if (NS_SUCCEEDED(result) && NS_SUCCEEDED(result = frame->PeekOffset(context, &pos)) && pos.mResultContent)
  {
    tHint = (HINT)pos.mPreferLeft;
    PRBool bidiEnabled = PR_FALSE;
    context->GetBidiEnabled(&bidiEnabled);
    if (bidiEnabled)
    {
      nsIFrame *theFrame;
      PRInt32 currentOffset, frameStart, frameEnd;
      PRUint8 level;

      // XXX - I expected to be able to use pos.mResultFrame, but when we move from frame to frame
      //       and |PeekOffset| is called recursively, pos.mResultFrame on exit is sometimes set to the original
      //       frame, not the frame that we ended up in, so I need this call to |GetFrameForNodeOffset|.
      //       I don't know if that could or should be changed or if it would break something else.
      GetFrameForNodeOffset(pos.mResultContent, pos.mContentOffset, tHint, &theFrame, &currentOffset);
      theFrame->GetOffsets(frameStart, frameEnd);

      // the hint might have been reversed by an RTL frame, so make sure of it
      if (nsIDOMKeyEvent::DOM_VK_HOME == aKeycode)
        pos.mPreferLeft = PR_TRUE;
      else if (nsIDOMKeyEvent::DOM_VK_END == aKeycode)
        pos.mPreferLeft = PR_FALSE;
      tHint = (HINT)pos.mPreferLeft;
      if (frameStart !=0 || frameEnd !=0) // Otherwise the frame is not a text frame, so nothing more to do
      {
        switch (aKeycode) {
          case nsIDOMKeyEvent::DOM_VK_HOME:
          case nsIDOMKeyEvent::DOM_VK_END:

            // force the offset to the logical beginning (for HOME) or end (for END) of the frame
            // (if it is an RTL frame it will be at the visual beginning or end, which we don't want in this case)
            if (nsIDOMKeyEvent::DOM_VK_HOME == aKeycode)
              pos.mContentOffset = frameStart;
            else
              pos.mContentOffset = frameEnd;

            // set the cursor Bidi level to the paragraph embedding level
            theFrame->GetBidiProperty(context, nsLayoutAtoms::baseLevel, (void**)&level,
                                      sizeof(level) );
            shell->SetCaretBidiLevel(level);
            break;

          default:
            // If the current position is not a frame boundary, it's enough just to take the Bidi level of the current frame
            if ((pos.mContentOffset != frameStart && pos.mContentOffset != frameEnd)
                || (eSelectDir == aAmount)
                || (eSelectLine == aAmount))
            {
              theFrame->GetBidiProperty(context, nsLayoutAtoms::embeddingLevel, (void**)&level,
                                        sizeof(level) );
              shell->SetCaretBidiLevel(level);
            }
            else
              BidiLevelFromMove(context, shell, pos.mResultContent, pos.mContentOffset, aKeycode);
        }
      }
#ifdef VISUALSELECTION
      // Handle visual selection
      if (aContinue)
      {
        result = VisualSelectFrames(context, theFrame, pos);
        if (NS_FAILED(result)) // Back out by collapsing the selection to the current position
          result = TakeFocus(pos.mResultContent, pos.mContentOffset, pos.mContentOffset, PR_FALSE, PR_FALSE);
      }    
      else
        result = TakeFocus(pos.mResultContent, pos.mContentOffset, pos.mContentOffset, aContinue, PR_FALSE);
    }
    else
#else
    }
#endif // VISUALSELECTION
    result = TakeFocus(pos.mResultContent, pos.mContentOffset, pos.mContentOffset, aContinue, PR_FALSE);
  }
  if (NS_SUCCEEDED(result))
  {
    mHint = tHint; //save the hint parameter now for the next time
    result = mDomSelections[index]->ScrollIntoView();
  }

  return result;
}



/** This raises a question, if this method is called and the aFrame does not reflect the current
 *  focus  DomNode, it is invalid?  The answer now is yes.
 */
NS_IMETHODIMP
nsSelection::HandleKeyEvent(nsIPresContext* aPresContext, nsGUIEvent *aGuiEvent)
{
  if (!aGuiEvent)
    return NS_ERROR_NULL_POINTER;
  STATUS_CHECK_RETURN_MACRO();

  nsresult result = NS_ERROR_FAILURE;
  if (NS_KEY_PRESS == aGuiEvent->message) {
    nsKeyEvent *keyEvent = (nsKeyEvent *)aGuiEvent; //this is ok. It really is a keyevent
    switch (keyEvent->keyCode)
    {
        case nsIDOMKeyEvent::DOM_VK_LEFT  : 
        case nsIDOMKeyEvent::DOM_VK_UP    :
        case nsIDOMKeyEvent::DOM_VK_DOWN  : 
        case nsIDOMKeyEvent::DOM_VK_RIGHT    :
        case nsIDOMKeyEvent::DOM_VK_HOME  : 
        case nsIDOMKeyEvent::DOM_VK_END    :
          break;
        default:
           return NS_ERROR_FAILURE;
    }

//XXX Need xp way get platfrom specific behavior into key navigation.
//XXX This really shouldn't have to use an ifdef
#ifdef _WIN32
    if (keyEvent->isAlt) {
      return NS_ERROR_FAILURE;
    }
#endif
    nsSelectionAmount amount = eSelectCharacter;
    if (keyEvent->isControl)
      amount = eSelectWord;
    return MoveCaret(keyEvent->keyCode, keyEvent->isShift, amount);
  }
  return result;
}

//END nsSelection methods


//BEGIN nsIFrameSelection methods

NS_IMETHODIMP
nsTypedSelection::ToString(PRUnichar **aReturn)
{
  return ToStringWithFormat("text/plain", 0, 0, aReturn);
}


NS_IMETHODIMP
nsTypedSelection::ToStringWithFormat(const char * aFormatType, PRUint32 aFlags, 
                                   PRInt32 aWrapCol, PRUnichar **aReturn)
{
  nsresult rv = NS_OK;
  if (!aReturn)
    return NS_ERROR_NULL_POINTER;
  
  nsCAutoString formatType( NS_DOC_ENCODER_CONTRACTID_BASE );
  formatType.Append(aFormatType);
  nsCOMPtr<nsIDocumentEncoder> encoder =
           do_CreateInstance(formatType.get(), &rv);
  NS_ENSURE_SUCCESS(rv, rv);

  nsCOMPtr<nsIPresShell> shell;
  rv = GetPresShell(getter_AddRefs(shell));
  if (NS_FAILED(rv) || !shell) {
    return NS_ERROR_FAILURE;
  }

  nsCOMPtr<nsIDocument> doc;
  rv = shell->GetDocument(getter_AddRefs(doc));
  NS_ENSURE_SUCCESS(rv, rv);

  // Flags should always include OutputSelectionOnly if we're coming from here:
  aFlags |= nsIDocumentEncoder::OutputSelectionOnly;
  nsAutoString readstring;
  readstring.AssignWithConversion(aFormatType);
  rv = encoder->Init(doc, readstring, aFlags);
  NS_ENSURE_SUCCESS(rv, rv);

  encoder->SetSelection(this);
  if (aWrapCol != 0)
    encoder->SetWrapColumn(aWrapCol);

  nsAutoString tmp;
  rv = encoder->EncodeToString(tmp);
  *aReturn = ToNewUnicode(tmp);//get the unicode pointer from it. this is temporary
  return rv;
}

NS_IMETHODIMP
nsTypedSelection::SetInterlinePosition(PRBool aHintRight)
{
  nsIFrameSelection::HINT hint;
  if (aHintRight)
    hint = nsIFrameSelection::HINTRIGHT;
  else
    hint = nsIFrameSelection::HINTLEFT;
  return mFrameSelection->SetHint(hint);
}

NS_IMETHODIMP
nsTypedSelection::GetInterlinePosition(PRBool *aHintRight)
{
  nsIFrameSelection::HINT hint;
  nsresult rv = mFrameSelection->GetHint(&hint);
  if (hint == nsIFrameSelection::HINTRIGHT)
    *aHintRight = PR_TRUE;
  else
    *aHintRight = PR_FALSE;
  return rv;
}

#ifdef VISUALSELECTION

static nsDirection
ReverseDirection(nsDirection aDirection)
{
  return (eDirNext == aDirection) ? eDirPrevious : eDirNext;
}

static nsresult
FindLineContaining(nsIFrame* aFrame, nsIFrame** aBlock, PRInt32* aLine)
{
  nsIFrame *blockFrame = aFrame;
  nsIFrame *thisBlock = nsnull;
  nsCOMPtr<nsILineIteratorNavigator> it; 
  nsresult result = NS_ERROR_FAILURE;
  while (NS_FAILED(result) && blockFrame)
  {
    thisBlock = blockFrame;
    blockFrame = blockFrame->GetParent();
    if (blockFrame) {
      it = do_QueryInterface(blockFrame, &result);
    }
  }
  if (!blockFrame || !it)
    return NS_ERROR_FAILURE;
  *aBlock = blockFrame;
  return it->FindLineContaining(thisBlock, aLine);  
}

NS_IMETHODIMP
nsSelection::VisualSequence(nsIPresContext *aPresContext,
                            nsIFrame* aSelectFrame,
                            nsIFrame* aCurrentFrame,
                            nsPeekOffsetStruct* aPos,
                            PRBool* aNeedVisualSelection)
{
  nsVoidArray frameArray;
  PRUint8 bidiLevel, currentLevel;
  PRInt32 frameStart, frameEnd;
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  nsresult result = nsnull;
  
  aCurrentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel, (void**)&currentLevel, sizeof(currentLevel) );

  result = aSelectFrame->PeekOffset(aPresContext, aPos);
  while (aCurrentFrame != (aSelectFrame = aPos->mResultFrame))
  {
    if (NS_FAILED(result))
      return NS_OK; // we have passed the end of the line, and we will carry on from there
    if (!aSelectFrame)
      return NS_ERROR_FAILURE;
    if (frameArray.IndexOf(aSelectFrame) > -1)
      // If we have already seen this frame, we must be in an infinite loop
      return NS_OK;
    else
      frameArray.AppendElement(aSelectFrame);

    aSelectFrame->GetOffsets(frameStart, frameEnd);
    aSelectFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel, (void**)&bidiLevel, sizeof(bidiLevel) );
    
    if (currentLevel != bidiLevel)
      *aNeedVisualSelection = PR_TRUE;
    if ((eDirNext == aPos->mDirection) == (bidiLevel & 1))
    {
      mDomSelections[index]->SetDirection(eDirPrevious);
      result = TakeFocus(aPos->mResultContent, frameEnd, frameStart, PR_FALSE, PR_TRUE);
    }
    else
    {
      mDomSelections[index]->SetDirection(eDirNext);
      result = TakeFocus(aPos->mResultContent, frameStart, frameEnd, PR_FALSE, PR_TRUE);
    }
    if (NS_FAILED(result))
      return result;

    aPos->mAmount = eSelectDir; // reset this because PeekOffset will have changed it to eSelectNoAmount
    aPos->mContentOffset = 0;
    result = aSelectFrame->PeekOffset(aPresContext, aPos);
  }
  
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::SelectToEdge(nsIFrame *aFrame, nsIContent *aContent, PRInt32 aOffset, PRInt32 aEdge, PRBool aMultipleSelection)
{
  PRInt32 frameStart, frameEnd;
  
  aFrame->GetOffsets(frameStart, frameEnd);
  if (0 == aEdge)
    aEdge = frameStart;
  else if (-1 == aEdge)
    aEdge = frameEnd;
  if (0 == aOffset)
    aOffset = frameStart;
  else if (-1 == aOffset)
    aOffset = frameEnd;
  return TakeFocus(aContent, aOffset, aEdge, PR_FALSE, aMultipleSelection);
}

NS_IMETHODIMP
nsSelection::SelectLines(nsIPresContext *aPresContext,
                         nsDirection aSelectionDirection,
                         nsIDOMNode *aAnchorNode,
                         nsIFrame* aAnchorFrame,
                         PRInt32 aAnchorOffset,
                         nsIDOMNode *aCurrentNode,
                         nsIFrame* aCurrentFrame,
                         PRInt32 aCurrentOffset,
                         nsPeekOffsetStruct aPos)
{
  nsIFrame *startFrame, *endFrame;
  PRInt32 startOffset, endOffset;
  PRInt32 relativePosition;
  nsCOMPtr<nsIDOMNode> startNode;
  nsCOMPtr<nsIDOMNode> endNode;
  nsIContent *startContent;
  nsIContent *endContent;
  nsresult result;

  // normalize the order before we start to avoid piles of conditions later
  relativePosition = ComparePoints(aAnchorNode, aAnchorOffset, aCurrentNode, aCurrentOffset);
  if (0 == relativePosition)
    return NS_ERROR_FAILURE;
  else if (relativePosition < 0)
  {
    startNode = aAnchorNode;
    startFrame = aAnchorFrame;
    startOffset = aAnchorOffset;
    endNode = aCurrentNode;
    endFrame = aCurrentFrame;
    endOffset = aCurrentOffset;
  }
  else
  {
    startNode = aCurrentNode;
    startFrame = aCurrentFrame;
    startOffset = aCurrentOffset;
    endNode = aAnchorNode;
    endFrame = aAnchorFrame;
    endOffset = aAnchorOffset;
  }

  aPos.mStartOffset = startOffset;
  aPos.mDirection = eDirNext;
  aPos.mAmount = eSelectLine;
  result = startFrame->PeekOffset(aPresContext, &aPos);
  if (NS_FAILED(result))
    return result;
  startFrame = aPos.mResultFrame;
  
  aPos.mStartOffset = aPos.mContentOffset;
  aPos.mAmount = eSelectBeginLine;
  result = startFrame->PeekOffset(aPresContext, &aPos);
  if (NS_FAILED(result))
    return result;
  
  nsIFrame *theFrame;
  PRInt32 currentOffset, frameStart, frameEnd;
  
  result = GetFrameForNodeOffset(aPos.mResultContent, aPos.mContentOffset, HINTLEFT, &theFrame, &currentOffset);
  if (NS_FAILED(result))
    return result;
  theFrame->GetOffsets(frameStart, frameEnd);
  startOffset = frameStart;
  startContent = aPos.mResultContent;
  startNode = do_QueryInterface(startContent);

  // If we have already overshot the endpoint, back out
  if (ComparePoints(startNode, startOffset, endNode, endOffset) >= 0)
    return NS_ERROR_FAILURE;

  aPos.mStartOffset = endOffset;
  aPos.mDirection = eDirPrevious;
  aPos.mAmount = eSelectLine;
  result = endFrame->PeekOffset(aPresContext, &aPos);
  if (NS_FAILED(result))
    return result;
  endFrame = aPos.mResultFrame;

  aPos.mStartOffset = aPos.mContentOffset;
  aPos.mAmount = eSelectEndLine;
  result = endFrame->PeekOffset(aPresContext, &aPos);
  if (NS_FAILED(result))
    return result;

  result = GetFrameForNodeOffset(aPos.mResultContent, aPos.mContentOffset, HINTRIGHT, &theFrame, &currentOffset);
  if (NS_FAILED(result))
    return result;
  theFrame->GetOffsets(frameStart, frameEnd);
  endOffset = frameEnd;
  endContent = aPos.mResultContent;
  endNode = do_QueryInterface(endContent);

  if (ComparePoints(startNode, startOffset, endNode, endOffset) < 0)
  {
    TakeFocus(startContent, startOffset, startOffset, PR_FALSE, PR_TRUE);
    return TakeFocus(endContent, endOffset, endOffset, PR_TRUE, PR_TRUE);
  }
  else
    return NS_ERROR_FAILURE;
}

NS_IMETHODIMP
nsSelection::VisualSelectFrames(nsIPresContext *aPresContext,
                                nsIFrame* aCurrentFrame,
                                nsPeekOffsetStruct aPos)
{
  nsCOMPtr<nsIContent> anchorContent;
  nsCOMPtr<nsIDOMNode> anchorNode;
  PRInt32 anchorOffset;
  nsIFrame* anchorFrame;
  PRUint8 anchorLevel;
  nsCOMPtr<nsIContent> focusContent;
  nsCOMPtr<nsIDOMNode> focusNode;
  PRInt32 focusOffset;
  nsIFrame* focusFrame;
  PRUint8 focusLevel;
  nsCOMPtr<nsIContent> currentContent;
  nsCOMPtr<nsIDOMNode> currentNode;
  PRInt32 currentOffset;
  PRUint8 currentLevel;
  nsresult result;
  nsIFrame* startFrame;
  PRBool needVisualSelection = PR_FALSE;
  nsDirection selectionDirection;
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);

  result = mDomSelections[index]->GetOriginalAnchorPoint(getter_AddRefs(anchorNode), &anchorOffset);
  if (NS_FAILED(result))
    return result;
  anchorContent = do_QueryInterface(anchorNode);
  result = GetFrameForNodeOffset(anchorContent, anchorOffset, mHint, &anchorFrame, &anchorOffset);
  if (NS_FAILED(result))
    return result;
  anchorFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel, (void**)&anchorLevel, sizeof(anchorLevel) );

  currentContent = aPos.mResultContent;
  currentNode = do_QueryInterface(currentContent);
  currentOffset = aPos.mContentOffset;
  aCurrentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel, (void**)&currentLevel, sizeof(currentLevel) );

  // Moving from simplest case to more complicated:
  // case 1: selection starts and ends in the same frame: no special treatment
  if (anchorFrame == aCurrentFrame) {
    mDomSelections[index]->SetTrueDirection(!(anchorLevel & 1));
    return TakeFocus(currentContent, anchorOffset, currentOffset, PR_FALSE, PR_FALSE);
  }

  focusOffset = mDomSelections[index]->FetchFocusOffset();
  focusNode = mDomSelections[index]->FetchFocusNode();
  focusContent = do_QueryInterface(focusNode);
  HINT hint;
  if ((HINTLEFT == mHint) == (currentLevel & 1))
    hint = HINTRIGHT;
  else
    hint = HINTLEFT;

  result = GetFrameForNodeOffset(focusContent, focusOffset, hint, &focusFrame, &focusOffset);
  if (NS_FAILED(result))
    return result;

  focusFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel, (void**)&focusLevel, sizeof(focusLevel) );

  if (currentLevel != anchorLevel)
    needVisualSelection = PR_TRUE;

  // Make sure of the selection direction
  selectionDirection = mDomSelections[index]->GetDirection();
  if (!mDomSelections[index]->GetTrueDirection()) {
    selectionDirection = ReverseDirection(selectionDirection);
    mDomSelections[index]->SetDirection(selectionDirection);
  }

  PRInt32 anchorLine, currentLine;
  nsIFrame* anchorBlock  = nsnull;
  nsIFrame* currentBlock = nsnull;
  FindLineContaining(anchorFrame, &anchorBlock, &anchorLine);
  FindLineContaining(aCurrentFrame, &currentBlock, &currentLine);

  if (anchorBlock==currentBlock && anchorLine==currentLine)
  {
    // case 2: selection starts and ends in the same line

    // Select from the anchor point to the edge of the frame
    // Which edge? If the selection direction is forward the right edge, if it is backward the left edge
    // For rtl frames the right edge is the begining of the frame, for ltr frames it is the end and vice versa
    if ((eDirNext == selectionDirection) == (anchorLevel & 1))
      result = SelectToEdge(anchorFrame, anchorContent, anchorOffset, 0, PR_FALSE);
    else
      result = SelectToEdge(anchorFrame, anchorContent, anchorOffset, -1, PR_FALSE);
    if (NS_FAILED(result))
      return result;

    // Walk the frames in visual order until we reach the current frame, selecting each frame as we go
    InvalidateDesiredX();
    aPos.mAmount = eSelectDir;
    aPos.mStartOffset = anchorOffset;
    aPos.mDirection = selectionDirection;

    result = anchorFrame->PeekOffset(aPresContext, &aPos);
    if (NS_FAILED(result))
      return result;
    
    startFrame = aPos.mResultFrame;
    result = VisualSequence(aPresContext, startFrame, aCurrentFrame, &aPos, &needVisualSelection);
    if (NS_FAILED(result))
      return result;

    if (!needVisualSelection)
    {
      if (currentLevel & 1)
        mDomSelections[index]->SetDirection(ReverseDirection(selectionDirection));
      // all the frames we passed through had the same Bidi level, so we can back out and do an ordinary selection
      result = TakeFocus(anchorContent, anchorOffset, anchorOffset, PR_FALSE, PR_FALSE);
      if (NS_FAILED(result))
        return result;
      result = TakeFocus(currentContent, currentOffset, currentOffset, PR_TRUE, PR_FALSE);
      if (NS_FAILED(result))
        return result;
    }
    else {
      if ((currentLevel & 1) != (focusLevel & 1))
        mDomSelections[index]->SetDirection(ReverseDirection(selectionDirection));
      // Select from the current point to the edge of the frame
      if ((eDirNext == selectionDirection) == (currentLevel & 1))
        result = SelectToEdge(aCurrentFrame, currentContent, -1, currentOffset, PR_TRUE);
      else
        result = SelectToEdge(aCurrentFrame, currentContent, 0, currentOffset, PR_TRUE);
      if (NS_FAILED(result))
        return result;
    }
  }
  else {

    // case 3: selection starts and ends in different lines

    // If selection direction is forwards:
    // Select from the anchor point to the edge of the frame in the direction of the end of the line
    // i.e. the rightmost character if the current paragraph embedding level is even (LTR paragraph)
    // or the leftmost character if the current paragraph embedding level is odd (RTL paragraph)
    //
    // As before, for rtl frames the right edge is the begining of the frame, for ltr frames it is the end and vice versa
    //
    // If selection direction is backwards, vice versa throughout
    //
    PRUint8 anchorBaseLevel;
    PRUint8 currentBaseLevel;
    anchorFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::baseLevel, (void**)&anchorBaseLevel, sizeof(anchorBaseLevel) );
    if ((eDirNext == selectionDirection) != ((anchorLevel & 1) == (anchorBaseLevel & 1)))
      result = SelectToEdge(anchorFrame, anchorContent, anchorOffset, 0, PR_FALSE);
    else
      result = SelectToEdge(anchorFrame, anchorContent, anchorOffset, -1, PR_FALSE);
    if (NS_FAILED(result))
      return result;

    // Walk the frames in visual order until we reach the end of the line
    aPos.mJumpLines = PR_FALSE;
    aPos.mAmount = eSelectDir;
    aPos.mStartOffset = anchorOffset;
    aPos.mDirection = selectionDirection;
    if (anchorBaseLevel & 1)
      aPos.mDirection = ReverseDirection(aPos.mDirection);
    result = VisualSequence(aPresContext, anchorFrame, aCurrentFrame, &aPos, &needVisualSelection);
    if (NS_FAILED(result))
      return result;

    // Select all the lines between the line containing the anchor point and the line containing the current point
    aPos.mJumpLines = PR_TRUE;
    result = SelectLines(aPresContext, selectionDirection,
                         anchorNode, anchorFrame, anchorOffset,
                         currentNode, aCurrentFrame, currentOffset, aPos);
    if (NS_FAILED(result))
      return result;

    // Go to the current point

    aCurrentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::baseLevel, (void**)&currentBaseLevel, sizeof(currentBaseLevel) );
    // Walk the frames in visual order until we reach the beginning of the line
    aPos.mJumpLines = PR_FALSE;
    if ((currentBaseLevel & 1) == (anchorBaseLevel & 1))
      aPos.mDirection = ReverseDirection(aPos.mDirection);
    aPos.mStartOffset = currentOffset;
    result = VisualSequence(aPresContext, aCurrentFrame, anchorFrame, &aPos, &needVisualSelection);
    if (NS_FAILED(result))
      return result;

    // Select from the current point to the edge of the frame
    if (currentLevel & 1)
      mDomSelections[index]->SetDirection(ReverseDirection(selectionDirection));

    if ((eDirPrevious == selectionDirection) != ((currentLevel & 1) == (currentBaseLevel & 1)))
      result = SelectToEdge(aCurrentFrame, currentContent, 0, currentOffset, PR_TRUE);
    else
      result = SelectToEdge(aCurrentFrame, currentContent, -1, currentOffset, PR_TRUE);
    if (NS_FAILED(result))
      return result;
    
    // restore original selection direction
//    mDomSelections[index]->SetDirection(selectionDirection);
  }

  // Sometimes we have to lie about the selection direction, so we will have to remember when we are doing so
  mDomSelections[index]->SetTrueDirection(mDomSelections[index]->GetDirection() == selectionDirection);
  
  mDomSelections[index]->SetOriginalAnchorPoint(anchorNode, anchorOffset);
  NotifySelectionListeners(nsISelectionController::SELECTION_NORMAL);
  return NS_OK;
}
#endif // VISUALSELECTION

NS_IMETHODIMP
nsSelection::GetPrevNextBidiLevels(nsIPresContext *aPresContext,
                                   nsIContent *aNode,
                                   PRUint32 aContentOffset,
                                   nsIFrame **aPrevFrame,
                                   nsIFrame **aNextFrame,
                                   PRUint8 *aPrevLevel,
                                   PRUint8 *aNextLevel)
{
  if (!aPrevFrame || !aNextFrame)
    return NS_ERROR_NULL_POINTER;
  // Get the level of the frames on each side
  nsIFrame    *currentFrame;
  PRInt32     currentOffset;
  PRInt32     frameStart, frameEnd;
  nsDirection direction;
  nsresult    result;

  *aPrevLevel = *aNextLevel = 0;

  result = GetFrameForNodeOffset(aNode, aContentOffset, mHint, &currentFrame, &currentOffset);
  if (NS_FAILED(result))
    return result;
  currentFrame->GetOffsets(frameStart, frameEnd);

  if (0 == frameStart && 0 == frameEnd)
    direction = eDirPrevious;
  else if (frameStart == currentOffset)
    direction = eDirPrevious;
  else if (frameEnd == currentOffset)
    direction = eDirNext;
  else {
    // we are neither at the beginning nor at the end of the frame, so we have no worries
    *aPrevFrame = *aNextFrame = currentFrame;
    currentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                                  (void**)aNextLevel, sizeof(*aNextLevel) );
    *aPrevLevel = *aNextLevel;
    return NS_OK;
  }

  /*
  we have to find the next or previous *logical* frame.

  Unfortunately |GetFrameFromDirection| has already been munged to return the next/previous *visual* frame, so we can't use that.
  The following code is taken from there without the Bidi changes.

  XXX is there a simpler way to do this? 
  */

  nsIFrame *blockFrame = currentFrame;
  nsIFrame *thisBlock = nsnull;
  PRInt32   thisLine;
  nsCOMPtr<nsILineIteratorNavigator> it; 
  result = NS_ERROR_FAILURE;
  while (NS_FAILED(result) && blockFrame)
  {
    thisBlock = blockFrame;
    blockFrame = blockFrame->GetParent();
    if (blockFrame) {
      it = do_QueryInterface(blockFrame, &result);
    }
  }
  if (!blockFrame || !it)
    return NS_ERROR_FAILURE;
  result = it->FindLineContaining(thisBlock, &thisLine);
  if (NS_FAILED(result))
    return result;

  if (thisLine < 0) 
    return NS_ERROR_FAILURE;

  nsIFrame *firstFrame;
  nsIFrame *lastFrame;
  nsRect    nonUsedRect;
  PRInt32   lineFrameCount;
  PRUint32  lineFlags;

  result = it->GetLine(thisLine, &firstFrame, &lineFrameCount,nonUsedRect,
                       &lineFlags);
  if (NS_FAILED(result))
    return result;

  lastFrame = firstFrame;

  for (;lineFrameCount > 1;lineFrameCount --) {
    lastFrame = lastFrame->GetNextSibling();
  }

  // GetFirstLeaf
  nsIFrame *lookahead;
  while (1) {
    lookahead = firstFrame->GetFirstChild(nsnull);
    if (!lookahead)
      break; //nothing to do
    firstFrame = lookahead;
  }

  // GetLastLeaf
  while (1) {
    lookahead = lastFrame->GetFirstChild(nsnull);
    if (!lookahead)
      break; //nothing to do
    lastFrame = lookahead;
    while ((lookahead = lastFrame->GetNextSibling()) != nsnull)
      lastFrame = lookahead;
  }
  //END LINE DATA CODE

  if (direction == eDirNext && lastFrame == currentFrame) { // End of line: set aPrevFrame to the current frame
                                                            //              set aPrevLevel to the embedding level of the current frame
                                                            //              set aNextFrame to null
                                                            //              set aNextLevel to the paragraph embedding level
    *aPrevFrame = currentFrame;
    currentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                                  (void**)aPrevLevel, sizeof(*aPrevLevel) );
    currentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::baseLevel,
                                  (void**)aNextLevel, sizeof(*aNextLevel) );
    *aNextFrame = nsnull;
    return NS_OK;
  }

  if (direction == eDirPrevious && firstFrame == currentFrame) { // Beginning of line: set aPrevFrame to null
                                                                 //                    set aPrevLevel to the paragraph embedding level
                                                                 //                    set aNextFrame to the current frame
                                                                 //                    set aNextLevel to the embedding level of the current frame
    *aNextFrame = currentFrame;
    currentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                                  (void**)aNextLevel, sizeof(*aNextLevel) );
    currentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::baseLevel,
                                  (void**)aPrevLevel, sizeof(*aPrevLevel) );
    *aPrevFrame = nsnull;
    return NS_OK;
  }

  // Find the adjacent frame

  nsCOMPtr<nsIBidirectionalEnumerator> frameTraversal;
  nsCOMPtr<nsIFrameTraversal> trav(do_CreateInstance(kFrameTraversalCID,&result));
  if (NS_FAILED(result))
    return result;

  result = trav->NewFrameTraversal(getter_AddRefs(frameTraversal),LEAF, aPresContext, currentFrame);
  if (NS_FAILED(result))
    return result;
  nsISupports *isupports = nsnull;
  if (direction == eDirNext)
    result = frameTraversal->Next();
  else 
    result = frameTraversal->Prev();

  if (NS_FAILED(result))
    return result;
  result = frameTraversal->CurrentItem(&isupports);
  if (NS_FAILED(result))
    return result;
  if (!isupports)
    return NS_ERROR_NULL_POINTER;
  //we must CAST here to an nsIFrame. nsIFrame doesnt really follow the rules
  //for speed reasons
  nsIFrame *newFrame = (nsIFrame *)isupports;

  if (direction == eDirNext) {
    *aPrevFrame = currentFrame;
    currentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                                  (void**)aPrevLevel, sizeof(*aPrevLevel) );
    *aNextFrame = newFrame;
    newFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                              (void**)aNextLevel, sizeof(*aNextLevel) );
  }
  else {
    *aNextFrame = currentFrame;
    currentFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                                  (void**)aNextLevel, sizeof(*aNextLevel) );
    *aPrevFrame = newFrame;
    newFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                              (void**)aPrevLevel, sizeof(*aPrevLevel) );
  }

  return NS_OK;

}

NS_IMETHODIMP nsSelection::GetFrameFromLevel(nsIPresContext *aPresContext,
                                             nsIFrame *aFrameIn,
                                             nsDirection aDirection,
                                             PRUint8 aBidiLevel,
                                             nsIFrame **aFrameOut)
{
  PRUint8 foundLevel = 0;
  nsIFrame *foundFrame = aFrameIn;

  nsCOMPtr<nsIBidirectionalEnumerator> frameTraversal;
  nsresult result;
  nsCOMPtr<nsIFrameTraversal> trav(do_CreateInstance(kFrameTraversalCID,&result));
  if (NS_FAILED(result))
      return result;

  result = trav->NewFrameTraversal(getter_AddRefs(frameTraversal),LEAF, aPresContext, aFrameIn);
  if (NS_FAILED(result))
    return result;
  nsISupports *isupports = nsnull;

  do {
    *aFrameOut = foundFrame;
    if (aDirection == eDirNext)
      result = frameTraversal->Next();
    else 
      result = frameTraversal->Prev();

    if (NS_FAILED(result))
      return result;
    result = frameTraversal->CurrentItem(&isupports);
    if (NS_FAILED(result))
      return result;
    if (!isupports)
      return NS_ERROR_NULL_POINTER;
    //we must CAST here to an nsIFrame. nsIFrame doesnt really follow the rules
    //for speed reasons
    foundFrame = (nsIFrame *)isupports;
    foundFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                                (void**)&foundLevel, sizeof(foundLevel) );

  } while (foundLevel > aBidiLevel);

  return NS_OK;
}


NS_IMETHODIMP 
nsSelection::MaintainSelection()
{
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  nsCOMPtr<nsIDOMRange> range;
  nsresult rv = mDomSelections[index]->GetRangeAt(0, getter_AddRefs(range));
  if (NS_FAILED(rv))
    return rv;
  if (!range)
    return NS_ERROR_FAILURE;

  nsCOMPtr<nsIDOMNode> startNode;
  nsCOMPtr<nsIDOMNode> endNode;
  PRInt32 startOffset;
  PRInt32 endOffset;
  range->GetStartContainer(getter_AddRefs(startNode));
  range->GetEndContainer(getter_AddRefs(endNode));
  range->GetStartOffset(&startOffset);
  range->GetEndOffset(&endOffset);

  mMaintainRange = nsnull;
  NS_NewRange(getter_AddRefs(mMaintainRange));
  if (!mMaintainRange)
    return NS_ERROR_OUT_OF_MEMORY;

  mMaintainRange->SetStart(startNode, startOffset);
  return mMaintainRange->SetEnd(endNode, endOffset);
}


/** After moving the caret, its Bidi level is set according to the following rules:
 *
 *  After moving over a character with left/right arrow, set to the Bidi level of the last moved over character.
 *  After Home and End, set to the paragraph embedding level.
 *  After up/down arrow, PageUp/Down, set to the lower level of the 2 surrounding characters.
 *  After mouse click, set to the level of the current frame.
 *
 *  The following two methods use GetPrevNextBidiLevels to determine the new Bidi level.
 *  BidiLevelFromMove is called when the caret is moved in response to a keyboard event
 *
 * @param aContext is the presentation context
 * @param aPresShell is the presentation shell
 * @param aNode is the content node
 * @param aContentOffset is the new caret position, as an offset into aNode
 * @param aKeycode is the keyboard event that moved the caret to the new position
 */
void nsSelection::BidiLevelFromMove(nsIPresContext* aContext,
                                    nsIPresShell* aPresShell,
                                    nsIContent *aNode,
                                    PRUint32 aContentOffset,
                                    PRUint32 aKeycode)
{
  PRUint8 firstLevel;
  PRUint8 secondLevel;
  PRUint8 currentLevel;
  nsIFrame* firstFrame=nsnull;
  nsIFrame* secondFrame=nsnull;

  aPresShell->GetCaretBidiLevel(&currentLevel);

  switch (aKeycode) {

    // Right and Left: the new cursor Bidi level is the level of the character moved over
    case nsIDOMKeyEvent::DOM_VK_RIGHT:
    case nsIDOMKeyEvent::DOM_VK_LEFT:
      GetPrevNextBidiLevels(aContext, aNode, aContentOffset, &firstFrame, &secondFrame, &firstLevel, &secondLevel);
      if (HINTLEFT==mHint)
        aPresShell->SetCaretBidiLevel(firstLevel);
      else
        aPresShell->SetCaretBidiLevel(secondLevel);
      break;

      /*
    // Up and Down: the new cursor Bidi level is the smaller of the two surrounding characters      
    case nsIDOMKeyEvent::DOM_VK_UP:
    case nsIDOMKeyEvent::DOM_VK_DOWN:
      GetPrevNextBidiLevels(aContext, aNode, aContentOffset, &firstFrame, &secondFrame, &firstLevel, &secondLevel);
      aPresShell->SetCaretBidiLevel(PR_MIN(firstLevel, secondLevel));
      break;
      */

    default:
      aPresShell->UndefineCaretBidiLevel();
  }
}

/**
 * BidiLevelFromClick is called when the caret is repositioned by clicking the mouse
 *
 * @param aNode is the content node
 * @param aContentOffset is the new caret position, as an offset into aNode
 */
void nsSelection::BidiLevelFromClick(nsIContent *aNode, PRUint32 aContentOffset)
{
  nsCOMPtr<nsIPresContext> context;
  nsresult result = mTracker->GetPresContext(getter_AddRefs(context));
  if (NS_FAILED(result) || !context)
    return;

  nsIPresShell *shell = context->GetPresShell();
  if (!shell)
    return;

  nsIFrame* clickInFrame=nsnull;
  PRUint8 frameLevel;
  PRInt32 OffsetNotUsed;

  result = GetFrameForNodeOffset(aNode, aContentOffset, mHint, &clickInFrame, &OffsetNotUsed);
  if (NS_FAILED(result))
    return;

  clickInFrame->GetBidiProperty(context, nsLayoutAtoms::embeddingLevel,
                                (void**)&frameLevel, sizeof(frameLevel) );
  shell->SetCaretBidiLevel(frameLevel);
}


PRBool
nsSelection::AdjustForMaintainedSelection(nsIContent *aContent, PRInt32 aOffset)
{
  // Is the desired content and offset currently in selection?
  // If the double click flag is set then don't continue selection if the 
  // desired content and offset are currently inside a selection.
  // This will stop double click then mouse-drag from undoing the desired
  // selecting of a word.
  if (!mMaintainRange)
    return PR_FALSE;

  nsCOMPtr<nsIDOMNode> rangenode;
  PRInt32 rangeOffset;
  mMaintainRange->GetStartContainer(getter_AddRefs(rangenode));
  mMaintainRange->GetStartOffset(&rangeOffset);

  nsCOMPtr<nsIDOMNode> domNode = do_QueryInterface(aContent);
  if (domNode)
  {
    PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
    nsCOMPtr<nsIDOMNSRange> nsrange = do_QueryInterface(mMaintainRange);
    if (nsrange)
    {
      PRBool insideSelection = PR_FALSE;
      nsrange->IsPointInRange(domNode, aOffset, &insideSelection);

      // Done when we find a range that we are in
      if (insideSelection)
      {
        mDomSelections[index]->Collapse(rangenode, rangeOffset);
        mMaintainRange->GetEndContainer(getter_AddRefs(rangenode));
        mMaintainRange->GetEndOffset(&rangeOffset);
        mDomSelections[index]->Extend(rangenode,rangeOffset);
        return PR_TRUE; // dragging in selection aborted
      }
    }

    PRInt32 relativePosition = ComparePoints(rangenode, rangeOffset, domNode, aOffset);
    // if == 0 or -1 do nothing if < 0 then we need to swap direction
    if (relativePosition > 0
        && (mDomSelections[index]->GetDirection() == eDirNext))
    {
      mMaintainRange->GetEndContainer(getter_AddRefs(rangenode));
      mMaintainRange->GetEndOffset(&rangeOffset);
      mDomSelections[index]->Collapse(rangenode, rangeOffset);
    }
    else if (relativePosition < 0
             && (mDomSelections[index]->GetDirection() == eDirPrevious))
      mDomSelections[index]->Collapse(rangenode, rangeOffset);
  }

  return PR_FALSE;
}


NS_IMETHODIMP
nsSelection::HandleClick(nsIContent *aNewFocus, PRUint32 aContentOffset, 
                       PRUint32 aContentEndOffset, PRBool aContinueSelection, 
                       PRBool aMultipleSelection, PRBool aHint) 
{
  if (!aNewFocus)
    return NS_ERROR_INVALID_ARG;

  InvalidateDesiredX();

  if (!aContinueSelection)
    mMaintainRange = nsnull;

  mHint = HINT(aHint);
  // Don't take focus when dragging off of a table
  if (!mDragSelectingCells)
  {
    BidiLevelFromClick(aNewFocus, aContentOffset);
    PostReason(nsISelectionListener::MOUSEDOWN_REASON + nsISelectionListener::DRAG_REASON);
    if (aContinueSelection &&
        AdjustForMaintainedSelection(aNewFocus, aContentOffset))
      return NS_OK; //shift clicked to maintained selection. rejected.

    return TakeFocus(aNewFocus, aContentOffset, aContentEndOffset, aContinueSelection, aMultipleSelection);
  }
  
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::HandleDrag(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint)
{
  if (!aPresContext || !aFrame)
    return NS_ERROR_NULL_POINTER;

  nsresult result;
  nsIFrame *newFrame = 0;
  nsPoint   newPoint;

  result = ConstrainFrameAndPointToAnchorSubtree(aPresContext, aFrame, aPoint, &newFrame, newPoint);
  if (NS_FAILED(result))
    return result;
  if (!newFrame)
    return NS_ERROR_FAILURE;

  PRInt32 startPos = 0;
  PRInt32 contentOffsetEnd = 0;
  PRBool  beginOfContent;
  nsCOMPtr<nsIContent> newContent;

  result = newFrame->GetContentAndOffsetsFromPoint(aPresContext, newPoint,
                                                   getter_AddRefs(newContent), 
                                                   startPos, contentOffsetEnd, beginOfContent);

  if ((newFrame->GetStateBits() & NS_FRAME_SELECTED_CONTENT) &&
       AdjustForMaintainedSelection(newContent, startPos))
    return NS_OK;

  // do we have CSS that changes selection behaviour?
  {
    //add scope for nsCOMPtr
    PRBool    changeSelection;
    nsCOMPtr<nsIContent>  selectContent;
    PRInt32   newStart, newEnd;
    if (NS_SUCCEEDED(AdjustOffsetsFromStyle(newFrame, &changeSelection, getter_AddRefs(selectContent), &newStart, &newEnd))
      && changeSelection)
    {
      newContent = selectContent;
      startPos = newStart;
      contentOffsetEnd = newEnd;
    }
  }

  if (NS_SUCCEEDED(result))
  {
#ifdef VISUALSELECTION
    PRBool bidiEnabled = PR_FALSE;
    aPresContext->GetBidiEnabled(&bidiEnabled);
    if (bidiEnabled) {
      PRUint8 level;
      nsPeekOffsetStruct pos;
      //set data using mLimiter to stop on scroll views.  If we have a limiter then we stop peeking
      //when we hit scrollable views.  If no limiter then just let it go ahead
      pos.SetData(mTracker, 0, eSelectDir, eDirNext, startPos, PR_FALSE,
                  PR_TRUE, PR_TRUE, mLimiter != nsnull, PR_FALSE);
      mHint = HINT(beginOfContent);
      HINT saveHint = mHint;
      newFrame->GetBidiProperty(aPresContext, nsLayoutAtoms::embeddingLevel,
                                (void**)&level,sizeof(level));
      if (level & 1)
        mHint = (mHint==HINTLEFT) ? HINTRIGHT : HINTLEFT;
      pos.mResultContent = newContent;
      pos.mContentOffset = contentOffsetEnd;
      result = VisualSelectFrames(aPresContext, newFrame, pos);
      if (NS_FAILED(result))
        result = HandleClick(newContent, startPos, contentOffsetEnd, PR_TRUE,
                             PR_FALSE, beginOfContent);
      mHint = saveHint;
    }
    else
#endif // VISUALSELECTION
      result = HandleClick(newContent, startPos, contentOffsetEnd, PR_TRUE,
                           PR_FALSE, beginOfContent);
  }

  return result;
}

NS_IMETHODIMP
nsSelection::StartAutoScrollTimer(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint, PRUint32 aDelay)
{
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  return mDomSelections[index]->StartAutoScrollTimer(aPresContext, aFrame, aPoint, aDelay);
}

NS_IMETHODIMP
nsSelection::StopAutoScrollTimer()
{
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  return mDomSelections[index]->StopAutoScrollTimer();
}

/**
hard to go from nodes to frames, easy the other way!
 */
NS_IMETHODIMP
nsSelection::TakeFocus(nsIContent *aNewFocus, PRUint32 aContentOffset, 
                       PRUint32 aContentEndOffset, PRBool aContinueSelection, PRBool aMultipleSelection)
{
  if (!aNewFocus)
    return NS_ERROR_NULL_POINTER;

  STATUS_CHECK_RETURN_MACRO();

  if (!IsValidSelectionPoint(this,aNewFocus))
    return NS_ERROR_FAILURE;

  // Clear all table selection data
  mSelectingTableCellMode = 0;
  mDragSelectingCells = PR_FALSE;
  mStartSelectedCell = nsnull;
  mEndSelectedCell = nsnull;
  mAppendStartSelectedCell = nsnull;

  //HACKHACKHACK
  if (!aNewFocus->GetParent())
    return NS_ERROR_FAILURE;
  //END HACKHACKHACK /checking for root frames/content

  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  nsCOMPtr<nsIDOMNode> domNode = do_QueryInterface(aNewFocus);
  //traverse through document and unselect crap here
  if (!aContinueSelection){ //single click? setting cursor down
    PRUint32 batching = mBatching;//hack to use the collapse code.
    PRBool changes = mChangesDuringBatching;
    mBatching = 1;

    if (aMultipleSelection){
      nsCOMPtr<nsIDOMRange> newRange;
      NS_NewRange(getter_AddRefs(newRange));

      newRange->SetStart(domNode,aContentOffset);
      newRange->SetEnd(domNode,aContentOffset);
      mDomSelections[index]->AddRange(newRange);
      mBatching = batching;
      mChangesDuringBatching = changes;
      mDomSelections[index]->SetOriginalAnchorPoint(domNode,aContentOffset);
    }
    else
    {
      PRBool oldDesiredXSet = mDesiredXSet; //need to keep old desired X if it was set.
      mDomSelections[index]->Collapse(domNode, aContentOffset);
      mDesiredXSet = oldDesiredXSet; //now reset desired X back.
      mBatching = batching;
      mChangesDuringBatching = changes;
    }
    if (aContentEndOffset != aContentOffset)
      mDomSelections[index]->Extend(domNode,aContentEndOffset);

    //find out if we are inside a table. if so, find out which one and which cell
    //once we do that, the next time we get a takefocus, check the parent tree. 
    //if we are no longer inside same table ,cell then switch to table selection mode.
    // BUT only do this in an editor

    nsCOMPtr<nsIPresContext> presContext;
    nsresult result = mTracker->GetPresContext(getter_AddRefs(presContext));
    if (NS_FAILED(result) || !presContext)
      return result?result:NS_ERROR_FAILURE;

    nsIPresShell *presShell = presContext->GetPresShell();
    if (!presShell)
      return NS_ERROR_FAILURE;

    PRInt16 displaySelection;
    result = presShell->GetSelectionFlags(&displaySelection);
    if (NS_FAILED(result))
      return result;

    // Editor has DISPLAY_ALL selection type
    if (displaySelection == nsISelectionDisplay::DISPLAY_ALL)
    {
      mCellParent = GetCellParent(domNode);
#ifdef DEBUG_TABLE_SELECTION
      if (mCellParent)
        printf(" * TakeFocus - Collapsing into new cell\n");
#endif
    }
  }
  else {
    // Now update the range list:
    if (aContinueSelection && domNode)
    {
      PRInt32 offset;
      nsIDOMNode *cellparent = GetCellParent(domNode);
      if (mCellParent && cellparent && cellparent != mCellParent) //switch to cell selection mode
      {
#ifdef DEBUG_TABLE_SELECTION
printf(" * TakeFocus - moving into new cell\n");
#endif
        nsCOMPtr<nsIDOMNode> parent;
        nsCOMPtr<nsIContent> parentContent;
        nsMouseEvent event;
        nsresult result;

        // Start selecting in the cell we were in before
        result = ParentOffset(mCellParent, getter_AddRefs(parent),&offset);
        parentContent = do_QueryInterface(parent);
        if (parentContent)
          result = HandleTableSelection(parentContent, offset, nsISelectionPrivate::TABLESELECTION_CELL, &event);

        // Find the parent of this new cell and extend selection to it
        result = ParentOffset(cellparent,getter_AddRefs(parent),&offset);
        parentContent = do_QueryInterface(parent);

        // XXXX We need to REALLY get the current key shift state
        //  (we'd need to add event listener -- let's not bother for now)
        event.isShift = PR_FALSE; //aContinueSelection;
        if (parentContent)
        {
          mCellParent = cellparent;
          // Continue selection into next cell
          result = HandleTableSelection(parentContent, offset, nsISelectionPrivate::TABLESELECTION_CELL, &event);
        }
      }
      else
      {
        // XXXX Problem: Shift+click in browser is appending text selection to selected table!!!
        //   is this the place to erase seleced cells ?????
        if (mDomSelections[index]->GetDirection() == eDirNext && aContentEndOffset > aContentOffset) //didnt go far enough 
        {
          mDomSelections[index]->Extend(domNode, aContentEndOffset);//this will only redraw the diff 
        }
        else
          mDomSelections[index]->Extend(domNode, aContentOffset);
      }
    }
  }

  // Don't notify selection listeners if batching is on:
  if (GetBatching())
    return NS_OK;
  return NotifySelectionListeners(nsISelectionController::SELECTION_NORMAL);
}



NS_METHOD
nsSelection::LookUpSelection(nsIContent *aContent, PRInt32 aContentOffset, PRInt32 aContentLength,
                             SelectionDetails **aReturnDetails, PRBool aSlowCheck)
{
  if (!aContent || !aReturnDetails)
    return NS_ERROR_NULL_POINTER;

  STATUS_CHECK_RETURN_MACRO();


  *aReturnDetails = nsnull;
  PRInt8 j;
  for (j = (PRInt8) 0; j < (PRInt8)nsISelectionController::NUM_SELECTIONTYPES; j++){
    if (mDomSelections[j])
     mDomSelections[j]->LookUpSelection(aContent, aContentOffset, aContentLength, aReturnDetails, (SelectionType)(1<<j), aSlowCheck);
  }
  return NS_OK;
}



NS_METHOD 
nsSelection::SetMouseDownState(PRBool aState)
{
  if (mMouseDownState == aState)
    return NS_OK;
  mMouseDownState = aState;
  if (!mMouseDownState)
  {
    PRInt16 reason;
    if (aState)
      reason = nsISelectionListener::MOUSEDOWN_REASON;
    else
      reason = nsISelectionListener::MOUSEUP_REASON;
    PostReason(reason);//not a drag reason
    NotifySelectionListeners(nsISelectionController::SELECTION_NORMAL);//notify that reason is mouse up please.
  }
  return NS_OK;
}



NS_METHOD
nsSelection::GetMouseDownState(PRBool *aState)
{
  if (!aState)
    return NS_ERROR_NULL_POINTER;
  *aState = mMouseDownState;
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::GetSelection(SelectionType aType, nsISelection **aDomSelection)
{
  if (!aDomSelection)
    return NS_ERROR_NULL_POINTER;
  PRInt8 index = GetIndexFromSelectionType(aType);
  if (index < 0)
    return NS_ERROR_INVALID_ARG;
  *aDomSelection = NS_REINTERPRET_CAST(nsISelection *,mDomSelections[index]);
  (*aDomSelection)->AddRef();
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::ScrollSelectionIntoView(SelectionType aType, SelectionRegion aRegion, PRBool aIsSynchronous)
{
  PRInt8 index = GetIndexFromSelectionType(aType);
  if (index < 0)
    return NS_ERROR_INVALID_ARG;

  if (!mDomSelections[index])
    return NS_ERROR_NULL_POINTER;

  return mDomSelections[index]->ScrollIntoView(aRegion, aIsSynchronous);
}

NS_IMETHODIMP
nsSelection::RepaintSelection(nsIPresContext* aPresContext, SelectionType aType)
{
  PRInt8 index = GetIndexFromSelectionType(aType);
  if (index < 0)
    return NS_ERROR_INVALID_ARG;
  if (!mDomSelections[index])
    return NS_ERROR_NULL_POINTER;
  return mDomSelections[index]->Repaint(aPresContext);
}
 
NS_IMETHODIMP
nsSelection::GetFrameForNodeOffset(nsIContent *aNode, PRInt32 aOffset, HINT aHint, nsIFrame **aReturnFrame, PRInt32 *aReturnOffset)
{
  if (!aNode || !aReturnFrame || !aReturnOffset)
    return NS_ERROR_NULL_POINTER;

  if (aOffset < 0)
    return NS_ERROR_FAILURE;

  *aReturnOffset = aOffset;

  nsresult result = NS_OK;

  nsCOMPtr<nsIContent> theNode = aNode;

  if (aNode->CanContainChildren())
  {
    PRInt32 childIndex  = 0;
    PRInt32 numChildren = 0;

    if (aHint == HINTLEFT)
    {
      if (aOffset > 0)
        childIndex = aOffset - 1;
      else
        childIndex = aOffset;
    }
    else // HINTRIGHT
    {
      numChildren = theNode->GetChildCount();

      if (aOffset >= numChildren)
      {
        if (numChildren > 0)
          childIndex = numChildren - 1;
        else
          childIndex = 0;
      }
      else
        childIndex = aOffset;
    }
    
    nsCOMPtr<nsIContent> childNode = theNode->GetChildAt(childIndex);

    if (!childNode)
      return NS_ERROR_FAILURE;

    theNode = childNode;

#ifdef DONT_DO_THIS_YET
    // XXX: We can't use this code yet because the hinting
    //      can cause us to attatch to the wrong line frame.

    // Now that we have the child node, check if it too
    // can contain children. If so, call this method again!

    if (theNode->CanContainChildren())
    {
      PRInt32 newOffset = 0;

      if (aOffset > childIndex)
      {
        numChildren = theNode->GetChildCount();

        newOffset = numChildren;
      }

      return GetFrameForNodeOffset(theNode, newOffset, aHint, aReturnFrame,aReturnOffset);
    }
    else
#endif // DONT_DO_THIS_YET
    {
      // Check to see if theNode is a text node. If it is, translate
      // aOffset into an offset into the text node.

      nsCOMPtr<nsIDOMText> textNode = do_QueryInterface(theNode);

      if (textNode)
      {
        if (aOffset > childIndex)
        {
          PRUint32 textLength = 0;

          result = textNode->GetLength(&textLength);

          if (NS_FAILED(result))
            return NS_ERROR_FAILURE;

          *aReturnOffset = (PRInt32)textLength;
        }
        else
          *aReturnOffset = 0;
      }
    }
  }
  
  result = mTracker->GetPrimaryFrameFor(theNode, aReturnFrame);
  if (NS_FAILED(result))
    return result;

  if (!*aReturnFrame)
    return NS_ERROR_UNEXPECTED;

  // find the child frame containing the offset we want
  result = (*aReturnFrame)->GetChildFrameContainingOffset(*aReturnOffset, aHint, &aOffset, aReturnFrame);
  return result;
}

NS_IMETHODIMP
nsSelection::CommonPageMove(PRBool aForward, 
                          PRBool aExtend, 
                          nsIScrollableView *aScrollableView,
                          nsIFrameSelection *aFrameSel)
{
  if ( !aScrollableView || !aFrameSel)
    return NS_ERROR_NULL_POINTER;
  // expected behavior for PageMove is to scroll AND move the caret
  // and remain relative position of the caret in view. see Bug 4302.

  nsresult result;
  const nsIView* clipView;
  //get the frame from the scrollable view

  nsIFrame* mainframe = nsnull;

  // The view's client data points back to its frame
  nsIView *scrolledView;
  result = aScrollableView->GetScrolledView(scrolledView);

  if (NS_FAILED(result))
    return result;

  if (scrolledView)
    mainframe = NS_STATIC_CAST(nsIFrame*, scrolledView->GetClientData());

  if (!mainframe)
    return NS_ERROR_FAILURE;

  // find out where we are; determine amount to page up/down
  if (NS_FAILED(result = aScrollableView->GetClipView(&clipView))) 
    return result;
  nsRect viewRect = clipView->GetBounds();

  nsCOMPtr<nsIPresContext> context;
  result = mTracker->GetPresContext(getter_AddRefs(context));
  
  if (NS_FAILED(result))
    return result;
  
  if (!context)
    return NS_ERROR_NULL_POINTER;

  nsIPresShell *shell = context->GetPresShell();
  
  if (!shell)
    return NS_ERROR_NULL_POINTER;

  // find out where the caret is.
  // we should know mDesiredX value of nsSelection, but I havent seen that behavior in other windows applications yet.
  nsCOMPtr<nsISelection> domSel;
  aFrameSel->GetSelection(nsISelectionController::SELECTION_NORMAL, getter_AddRefs(domSel));
  
  if (!domSel) 
    return NS_ERROR_UNEXPECTED;
  
  nsCOMPtr<nsICaret> caret;
  nsRect caretPos;
  PRBool isCollapsed;
  result = shell->GetCaret(getter_AddRefs(caret));
  
  if (NS_FAILED(result)) 
    return result;
  
  nsIView *caretView;
  result = caret->GetCaretCoordinates(nsICaret::eClosestViewCoordinates, domSel, &caretPos, &isCollapsed, &caretView);
  
  if (NS_FAILED(result)) 
    return result;
  
  //need to adjust caret jump by percentage scroll
  viewRect.height = (PRInt32) (viewRect.height * PAGE_SCROLL_PERCENT);
  
  if (aForward)
    caretPos.y += viewRect.height;
  else
    caretPos.y -= viewRect.height;

  
  if (caretView)
  {
    while (caretView != scrolledView)
    {
      caretPos += caretView->GetPosition();
      caretView = caretView->GetParent();
      if (!caretView) //how did we miss the scrolled view. something is very wrong
        return NS_ERROR_FAILURE;
    }
  }
    
  // get a content at desired location
  nsCOMPtr<nsIContent> content;
  PRInt32 startOffset, endOffset;
  PRBool beginFrameContent;
  nsPoint desiredPoint;
  desiredPoint.x = caretPos.x;
  desiredPoint.y = caretPos.y + caretPos.height/2;
  result = mainframe->GetContentAndOffsetsFromPoint(context, desiredPoint, getter_AddRefs(content), startOffset, endOffset, beginFrameContent);
  
  if (NS_FAILED(result)) 
    return result;
  
  if (!content) 
    return NS_ERROR_UNEXPECTED;

  // scroll one page

  aScrollableView->ScrollByPages(0, aForward ? 1 : -1);
  
  // place the caret
  result = aFrameSel->HandleClick(content, startOffset, startOffset, aExtend, PR_FALSE, PR_TRUE);
  
  return result;
}

NS_IMETHODIMP 
nsSelection::CharacterMove(PRBool aForward, PRBool aExtend)
{
  if (aForward)
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_RIGHT,aExtend,eSelectCharacter);
  else
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_LEFT,aExtend,eSelectCharacter);
}

NS_IMETHODIMP
nsSelection::WordMove(PRBool aForward, PRBool aExtend)
{
  if (aForward)
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_RIGHT,aExtend,eSelectWord);
  else
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_LEFT,aExtend,eSelectWord);
}

NS_IMETHODIMP
nsSelection::LineMove(PRBool aForward, PRBool aExtend)
{
  if (aForward)
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_DOWN,aExtend,eSelectLine);
  else
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_UP,aExtend,eSelectLine);
}

NS_IMETHODIMP
nsSelection::IntraLineMove(PRBool aForward, PRBool aExtend)
{
  if (aForward)
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_END,aExtend,eSelectLine);
  else
    return MoveCaret(nsIDOMKeyEvent::DOM_VK_HOME,aExtend,eSelectLine);
}

NS_IMETHODIMP nsSelection::SelectAll()
{
  nsCOMPtr<nsIContent> rootContent;
  if (mLimiter)
  {
    rootContent = mLimiter;//addrefit
  }
  else
  {
    nsresult rv;
    nsCOMPtr<nsIPresShell> shell(do_QueryInterface(mTracker,&rv));
    if (NS_FAILED(rv) || !shell) {
      return NS_ERROR_FAILURE;
    }

    nsCOMPtr<nsIDocument> doc;
    rv = shell->GetDocument(getter_AddRefs(doc));
    if (NS_FAILED(rv))
      return rv;
    if (!doc)
      return NS_ERROR_FAILURE;
    rootContent = doc->GetRootContent();
    if (!rootContent)
      return NS_ERROR_FAILURE;
  }
  PRInt32 numChildren = rootContent->GetChildCount();
  PostReason(nsISelectionListener::NO_REASON);
  return TakeFocus(mLimiter, 0, numChildren, PR_FALSE, PR_FALSE);
}

//////////END FRAMESELECTION

NS_IMETHODIMP
nsSelection::StartBatchChanges()
{
  nsresult result(NS_OK);
  mBatching++;
  return result;
}

 
NS_IMETHODIMP
nsSelection::EndBatchChanges()
{
  nsresult result(NS_OK);
  mBatching--;
  NS_ASSERTION(mBatching >=0,"Bad mBatching");
  if (mBatching == 0 && mChangesDuringBatching){
    mChangesDuringBatching = PR_FALSE;
    NotifySelectionListeners(nsISelectionController::SELECTION_NORMAL);
  }
  return result;
}


nsresult
nsSelection::NotifySelectionListeners(SelectionType aType)
{
  PRInt8 index = GetIndexFromSelectionType(aType);
  if (index >=0)
  {
    return mDomSelections[index]->NotifySelectionListeners();
  }
  return NS_ERROR_FAILURE;
}

nsresult
nsSelection::FrameOrParentHasSpecialSelectionStyle(nsIFrame* aFrame, PRUint8 aSelectionStyle, nsIFrame* *foundFrame)
{
  nsIFrame* thisFrame = aFrame;
  
  while (thisFrame)
  {
    if (thisFrame->GetStyleUIReset()->mUserSelect == aSelectionStyle)
    {
      *foundFrame = thisFrame;
      return NS_OK;
    }
  
    thisFrame = thisFrame->GetParent();
  }
  
  *foundFrame = nsnull;
  return NS_OK;
}


// Start of Table Selection methods

static PRBool IsCell(nsIContent *aContent)
{
  return (aContent->Tag() == nsHTMLAtoms::td &&
          aContent->IsContentOfType(nsIContent::eHTML));
}

nsITableCellLayout* 
nsSelection::GetCellLayout(nsIContent *aCellContent)
{
  // Get frame for cell
  nsIFrame *cellFrame = nsnull;
  GetTracker()->GetPrimaryFrameFor(aCellContent, &cellFrame);
  if (!cellFrame)
    return nsnull;

  nsITableCellLayout *cellLayoutObject = nsnull;
  CallQueryInterface(cellFrame, &cellLayoutObject);

  return cellLayoutObject;
}

nsITableLayout* 
nsSelection::GetTableLayout(nsIContent *aTableContent)
{
  // Get frame for table
  nsIFrame *tableFrame = nsnull;
  GetTracker()->GetPrimaryFrameFor(aTableContent, &tableFrame);
  if (!tableFrame)
    return nsnull;

  nsITableLayout *tableLayoutObject = nsnull;
  CallQueryInterface(tableFrame, &tableLayoutObject);

  return tableLayoutObject;
}

nsresult
nsSelection::ClearNormalSelection()
{
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  return mDomSelections[index]->RemoveAllRanges();
}

// Table selection support.
// TODO: Separate table methods into a separate nsITableSelection interface
nsresult
nsSelection::HandleTableSelection(nsIContent *aParentContent, PRInt32 aContentOffset, PRInt32 aTarget, nsMouseEvent *aMouseEvent)
{
  NS_ENSURE_TRUE(aParentContent, NS_ERROR_NULL_POINTER);
  NS_ENSURE_TRUE(aMouseEvent, NS_ERROR_NULL_POINTER);

  if (mMouseDownState && mDragSelectingCells && (aTarget & nsISelectionPrivate::TABLESELECTION_TABLE))
  {
    // We were selecting cells and user drags mouse in table border or inbetween cells,
    //  just do nothing
      return NS_OK;
  }

  nsCOMPtr<nsIDOMNode> parentNode = do_QueryInterface(aParentContent);
  if (!parentNode)
    return NS_ERROR_FAILURE;

  nsresult result = NS_OK;

  nsIContent *childContent = aParentContent->GetChildAt(aContentOffset);
  nsCOMPtr<nsIDOMNode> childNode = do_QueryInterface(childContent);
  if (!childNode)
    return NS_ERROR_FAILURE;

  // When doing table selection, always set the direction to next so
  // we can be sure that anchorNode's offset always points to the
  // selected cell
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  mDomSelections[index]->SetDirection(eDirNext);

  // Stack-class to wrap all table selection changes in 
  //  BeginBatchChanges() / EndBatchChanges()
  nsSelectionBatcher selectionBatcher(mDomSelections[index]);

  PRInt32 startRowIndex, startColIndex, curRowIndex, curColIndex;
  if (mMouseDownState && mDragSelectingCells)
  {
    // We are drag-selecting
    if (aTarget != nsISelectionPrivate::TABLESELECTION_TABLE)
    {
      // If dragging in the same cell as last event, do nothing
      if (mEndSelectedCell == childContent)
        return NS_OK;

#ifdef DEBUG_TABLE_SELECTION
printf(" mStartSelectedCell = %x, mEndSelectedCell = %x, childContent = %x \n", mStartSelectedCell, mEndSelectedCell, childContent);
#endif
      // aTarget can be any "cell mode",
      //  so we can easily drag-select rows and columns 
      // Once we are in row or column mode,
      //  we can drift into any cell to stay in that mode
      //  even if aTarget = TABLESELECTION_CELL

      if (mSelectingTableCellMode == nsISelectionPrivate::TABLESELECTION_ROW ||
          mSelectingTableCellMode == nsISelectionPrivate::TABLESELECTION_COLUMN)
      {
        if (mEndSelectedCell)
        {
          // Also check if cell is in same row/col
          result = GetCellIndexes(mEndSelectedCell, startRowIndex, startColIndex);
          if (NS_FAILED(result)) return result;
          result = GetCellIndexes(childContent, curRowIndex, curColIndex);
          if (NS_FAILED(result)) return result;
        
#ifdef DEBUG_TABLE_SELECTION
printf(" curRowIndex = %d, startRowIndex = %d, curColIndex = %d, startColIndex = %d\n", curRowIndex, startRowIndex, curColIndex, startColIndex);
#endif
          if ((mSelectingTableCellMode == nsISelectionPrivate::TABLESELECTION_ROW && startRowIndex == curRowIndex) ||
              (mSelectingTableCellMode == nsISelectionPrivate::TABLESELECTION_COLUMN && startColIndex == curColIndex)) 
            return NS_OK;
        }
#ifdef DEBUG_TABLE_SELECTION
printf(" Dragged into a new column or row\n");
#endif
        // Continue dragging row or column selection
        return SelectRowOrColumn(childContent, mSelectingTableCellMode);
      }
      else if (mSelectingTableCellMode == nsISelectionPrivate::TABLESELECTION_CELL)
      {
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Dragged into a new cell\n");
#endif
        // Trick for quick selection of rows and columns
        // Hold down shift, then start selecting in one direction
        // If next cell dragged into is in same row, select entire row,
        //   if next cell is in same column, select entire column
        if (mStartSelectedCell && aMouseEvent->isShift)
        {
          result = GetCellIndexes(mStartSelectedCell, startRowIndex, startColIndex);
          if (NS_FAILED(result)) return result;
          result = GetCellIndexes(childContent, curRowIndex, curColIndex);
          if (NS_FAILED(result)) return result;
          
          if (startRowIndex == curRowIndex || 
              startColIndex == curColIndex)
          {
            // Force new selection block
            mStartSelectedCell = nsnull;
            mDomSelections[index]->RemoveAllRanges();

            if (startRowIndex == curRowIndex)
              mSelectingTableCellMode = nsISelectionPrivate::TABLESELECTION_ROW;
            else
              mSelectingTableCellMode = nsISelectionPrivate::TABLESELECTION_COLUMN;

            return SelectRowOrColumn(childContent, mSelectingTableCellMode);
          }
        }
        
        // Reselect block of cells to new end location
        return SelectBlockOfCells(mStartSelectedCell, childContent);
      }
    }
    // Do nothing if dragging in table, but outside a cell
    return NS_OK;
  }
  else 
  {
    // Not dragging  -- mouse event is down or up
    if (mMouseDownState)
    {
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Mouse down event\n");
#endif
      // Clear cell we stored in mouse-down
      mUnselectCellOnMouseUp = nsnull;
      
      if (aTarget == nsISelectionPrivate::TABLESELECTION_CELL)
      {
        PRBool isSelected = PR_FALSE;

        // Check if we have other selected cells
        nsCOMPtr<nsIDOMNode> previousCellNode;
        GetFirstSelectedCellAndRange(getter_AddRefs(previousCellNode), nsnull);
        if (previousCellNode)
        {
          // We have at least 1 other selected cell

          // Check if new cell is already selected
          nsIFrame  *cellFrame = nsnull;
          result = GetTracker()->GetPrimaryFrameFor(childContent, &cellFrame);
          if (NS_FAILED(result)) return result;
          if (!cellFrame) return NS_ERROR_NULL_POINTER;
          result = cellFrame->GetSelected(&isSelected);
          if (NS_FAILED(result)) return result;
        }
        else
        {
          // No cells selected -- remove non-cell selection
          mDomSelections[index]->RemoveAllRanges();
        }
        mDragSelectingCells = PR_TRUE;    // Signal to start drag-cell-selection
        mSelectingTableCellMode = aTarget;
        // Set start for new drag-selection block (not appended)
        mStartSelectedCell = childContent;
        // The initial block end is same as the start
        mEndSelectedCell = childContent;
        
        if (isSelected)
        {
          // Remember this cell to (possibly) unselect it on mouseup
          mUnselectCellOnMouseUp = childContent;
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Saving mUnselectCellOnMouseUp\n");
#endif
        }
        else
        {
          // Select an unselected cell
          // but first remove existing selection if not in same table
          nsCOMPtr<nsIContent> previousCellContent = do_QueryInterface(previousCellNode);
          if (previousCellContent && !IsInSameTable(previousCellContent, childContent, nsnull))
          {
            mDomSelections[index]->RemoveAllRanges();
            // Reset selection mode that is cleared in RemoveAllRanges
            mSelectingTableCellMode = aTarget;
          }

          nsCOMPtr<nsIDOMElement> cellElement = do_QueryInterface(childContent);
          return SelectCellElement(cellElement);
        }

        return NS_OK;
      }
      else if (aTarget == nsISelectionPrivate::TABLESELECTION_TABLE)
      {
        //TODO: We currently select entire table when clicked between cells,
        //  should we restrict to only around border?
        //  *** How do we get location data for cell and click?
        mDragSelectingCells = PR_FALSE;
        mStartSelectedCell = nsnull;
        mEndSelectedCell = nsnull;

        // Remove existing selection and select the table
        mDomSelections[index]->RemoveAllRanges();
        return CreateAndAddRange(parentNode, aContentOffset);
      }
      else if (aTarget == nsISelectionPrivate::TABLESELECTION_ROW || aTarget == nsISelectionPrivate::TABLESELECTION_COLUMN)
      {
#ifdef DEBUG_TABLE_SELECTION
printf("aTarget == %d\n", aTarget);
#endif

        // Start drag-selecting mode so multiple rows/cols can be selected
        // Note: Currently, nsFrame::GetDataForTableSelection
        //       will never call us for row or column selection on mouse down
        mDragSelectingCells = PR_TRUE;
      
        // Force new selection block
        mStartSelectedCell = nsnull;
        mDomSelections[index]->RemoveAllRanges();
        // Always do this AFTER RemoveAllRanges
        mSelectingTableCellMode = aTarget;
        return SelectRowOrColumn(childContent, aTarget);
      }
    }
    else
    {
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Mouse UP event. mDragSelectingCells=%d, mStartSelectedCell=%d\n", mDragSelectingCells, mStartSelectedCell);
#endif
      // First check if we are extending a block selection
      PRInt32 rangeCount;
      result = mDomSelections[index]->GetRangeCount(&rangeCount);
      if (NS_FAILED(result)) 
        return result;

      if (rangeCount > 0 && aMouseEvent->isShift && 
          mAppendStartSelectedCell && mAppendStartSelectedCell != childContent)
      {
        // Shift key is down: append a block selection
        mDragSelectingCells = PR_FALSE;
        return SelectBlockOfCells(mAppendStartSelectedCell, childContent);
      }

      if (mDragSelectingCells)
        mAppendStartSelectedCell = mStartSelectedCell;
        
      mDragSelectingCells = PR_FALSE;
      mStartSelectedCell = nsnull;
      mEndSelectedCell = nsnull;

      // Any other mouseup actions require that Ctrl or Cmd key is pressed
      //  else stop table selection mode
      PRBool doMouseUpAction = PR_FALSE;
#if defined(XP_MAC) || defined(XP_MACOSX)
      doMouseUpAction = aMouseEvent->isMeta;
#else
      doMouseUpAction = aMouseEvent->isControl;
#endif
      if (!doMouseUpAction)
      {
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Ending cell selection on mouseup: mAppendStartSelectedCell=%d\n", mAppendStartSelectedCell);
#endif
        return NS_OK;
      }
      // Unselect a cell only if it wasn't
      //  just selected on mousedown
      if( childContent == mUnselectCellOnMouseUp)
      {
        // Scan ranges to find the cell to unselect (the selection range to remove)
        nsCOMPtr<nsIDOMNode> previousCellParent;
        nsCOMPtr<nsIDOMRange> range;
        PRInt32 offset;
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Unselecting mUnselectCellOnMouseUp; rangeCount=%d\n", rangeCount);
#endif
        for( PRInt32 i = 0; i < rangeCount; i++)
        {
          result = mDomSelections[index]->GetRangeAt(i, getter_AddRefs(range));
          if (NS_FAILED(result)) return result;
          if (!range) return NS_ERROR_NULL_POINTER;

          nsCOMPtr<nsIDOMNode> parent;
          result = range->GetStartContainer(getter_AddRefs(parent));
          if (NS_FAILED(result)) return result;
          if (!parent) return NS_ERROR_NULL_POINTER;

          range->GetStartOffset(&offset);
          // Be sure previous selection is a table cell
          nsCOMPtr<nsIContent> parentContent = do_QueryInterface(parent);
          nsCOMPtr<nsIContent> child = parentContent->GetChildAt(offset);
          if (child && IsCell(child))
            previousCellParent = parent;

          // We're done if we didn't find parent of a previously-selected cell
          if (!previousCellParent) break;
        
          if (previousCellParent == parentNode && offset == aContentOffset)
          {
            // Cell is already selected
            if (rangeCount == 1)
            {
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Unselecting single selected cell\n");
#endif
              // This was the only cell selected.
              // Collapse to "normal" selection inside the cell
              mStartSelectedCell = nsnull;
              mEndSelectedCell = nsnull;
              mAppendStartSelectedCell = nsnull;
              //TODO: We need a "Collapse to just before deepest child" routine
              // Even better, should we collapse to just after the LAST deepest child
              //  (i.e., at the end of the cell's contents)?
              return mDomSelections[index]->Collapse(childNode, 0);
            }
#ifdef DEBUG_TABLE_SELECTION
printf("HandleTableSelection: Removing cell from multi-cell selection\n");
#endif
            // Unselecting the start of previous block 
            // XXX What do we use now!
            if (childContent == mAppendStartSelectedCell)
               mAppendStartSelectedCell = nsnull;

            // Deselect cell by removing its range from selection
            return mDomSelections[index]->RemoveRange(range);
          }
        }
        mUnselectCellOnMouseUp = nsnull;
      }
    }
  }
  return result;
}

nsresult
nsSelection::SelectBlockOfCells(nsIContent *aStartCell, nsIContent *aEndCell)
{
  NS_ENSURE_TRUE(aStartCell, NS_ERROR_NULL_POINTER);
  NS_ENSURE_TRUE(aEndCell, NS_ERROR_NULL_POINTER);
  mEndSelectedCell = aEndCell;

  nsCOMPtr<nsIContent> startCell;
  nsresult result = NS_OK;

  // If new end cell is in a different table, do nothing
  nsCOMPtr<nsIContent> table;
  if (!IsInSameTable(aStartCell, aEndCell, getter_AddRefs(table)))
    return NS_OK;

  // Get starting and ending cells' location in the cellmap
  PRInt32 startRowIndex, startColIndex, endRowIndex, endColIndex;
  result = GetCellIndexes(aStartCell, startRowIndex, startColIndex);
  if(NS_FAILED(result)) return result;
  result = GetCellIndexes(aEndCell, endRowIndex, endColIndex);
  if(NS_FAILED(result)) return result;

  // Get TableLayout interface to access cell data based on cellmap location
  // frames are not ref counted, so don't use an nsCOMPtr
  nsITableLayout *tableLayoutObject = GetTableLayout(table);
  if (!tableLayoutObject) return NS_ERROR_FAILURE;

  PRInt32 curRowIndex, curColIndex;

  if (mDragSelectingCells)
  {
    // Drag selecting: remove selected cells outside of new block limits

    PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);

    nsCOMPtr<nsIDOMNode> cellNode;
    nsCOMPtr<nsIDOMRange> range;
    result = GetFirstSelectedCellAndRange(getter_AddRefs(cellNode), getter_AddRefs(range));
    if (NS_FAILED(result)) return result;

    PRInt32 minRowIndex = PR_MIN(startRowIndex, endRowIndex);
    PRInt32 maxRowIndex = PR_MAX(startRowIndex, endRowIndex);
    PRInt32 minColIndex = PR_MIN(startColIndex, endColIndex);
    PRInt32 maxColIndex = PR_MAX(startColIndex, endColIndex);

    while (cellNode)
    {
      nsCOMPtr<nsIContent> childContent = do_QueryInterface(cellNode);
      result = GetCellIndexes(childContent, curRowIndex, curColIndex);
      if (NS_FAILED(result)) return result;

#ifdef DEBUG_TABLE_SELECTION
if (!range)
printf("SelectBlockOfCells -- range is null\n");
#endif
      if (range &&
          (curRowIndex < minRowIndex || curRowIndex > maxRowIndex || 
           curColIndex < minColIndex || curColIndex > maxColIndex))
      {
        mDomSelections[index]->RemoveRange(range);
        // Since we've removed the range, decrement pointer to next range
        mSelectedCellIndex--;
      }    
      result = GetNextSelectedCellAndRange(getter_AddRefs(cellNode), getter_AddRefs(range));
      if (NS_FAILED(result)) return result;
    }
  }

  nsCOMPtr<nsIDOMElement> cellElement;
  PRInt32 rowSpan, colSpan, actualRowSpan, actualColSpan;
  PRBool  isSelected;

  // Note that we select block in the direction of user's mouse dragging,
  //  which means start cell may be after the end cell in either row or column
  PRInt32 row = startRowIndex;
  while(PR_TRUE)
  {
    PRInt32 col = startColIndex;
    while(PR_TRUE)
    {
      result = tableLayoutObject->GetCellDataAt(row, col, *getter_AddRefs(cellElement),
                                                curRowIndex, curColIndex, rowSpan, colSpan, 
                                                actualRowSpan, actualColSpan, isSelected);
      if (NS_FAILED(result)) return result;

      NS_ASSERTION(actualColSpan, "!actualColSpan is 0!");

      // Skip cells that are spanned from previous locations or are already selected
      if (!isSelected && cellElement && row == curRowIndex && col == curColIndex)
      {
        result = SelectCellElement(cellElement);
        if (NS_FAILED(result)) return result;
      }
      // Done when we reach end column
      if (col == endColIndex) break;

      if (startColIndex < endColIndex)
        col ++;
      else
        col--;
    };
    if (row == endRowIndex) break;

    if (startRowIndex < endRowIndex)
      row++;
    else
      row--;
  };
  return result;
}

nsresult
nsSelection::SelectRowOrColumn(nsIContent *aCellContent, PRUint32 aTarget)
{
  if (!aCellContent) return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsIContent> table;
  nsresult result = GetParentTable(aCellContent, getter_AddRefs(table));
  if (NS_FAILED(result)) return PR_FALSE;
  if (!table) return NS_ERROR_NULL_POINTER;

  // Get table and cell layout interfaces to access 
  //   cell data based on cellmap location
  // Frames are not ref counted, so don't use an nsCOMPtr
  nsITableLayout *tableLayout = GetTableLayout(table);
  if (!tableLayout) return NS_ERROR_FAILURE;
  nsITableCellLayout *cellLayout = GetCellLayout(aCellContent);
  if (!cellLayout) return NS_ERROR_FAILURE;

  // Get location of target cell:      
  PRInt32 rowIndex, colIndex, curRowIndex, curColIndex;
  result = cellLayout->GetCellIndexes(rowIndex, colIndex);
  if (NS_FAILED(result)) return result;

  // Be sure we start at proper beginning
  // (This allows us to select row or col given ANY cell!)
  if (aTarget == nsISelectionPrivate::TABLESELECTION_ROW)
    colIndex = 0;
  if (aTarget == nsISelectionPrivate::TABLESELECTION_COLUMN)
    rowIndex = 0;

  nsCOMPtr<nsIDOMElement> cellElement;
  nsCOMPtr<nsIDOMElement> firstCell;
  nsCOMPtr<nsIDOMElement> lastCell;
  PRInt32 rowSpan, colSpan, actualRowSpan, actualColSpan;
  PRBool isSelected;

  do {
    // Loop through all cells in column or row to find first and last
    result = tableLayout->GetCellDataAt(rowIndex, colIndex, *getter_AddRefs(cellElement),
                                        curRowIndex, curColIndex, rowSpan, colSpan, 
                                        actualRowSpan, actualColSpan, isSelected);
    if (NS_FAILED(result)) return result;
    if (cellElement)
    {
      NS_ASSERTION(actualRowSpan > 0 && actualColSpan> 0, "SelectRowOrColumn: Bad rowspan or colspan\n");
      if (!firstCell)
        firstCell = cellElement;

      lastCell = cellElement;

      // Move to next cell in cellmap, skipping spanned locations
      if (aTarget == nsISelectionPrivate::TABLESELECTION_ROW)
        colIndex += actualColSpan;
      else
        rowIndex += actualRowSpan;
    }
  }
  while (cellElement);

  // Use SelectBlockOfCells:
  // This will replace existing selection,
  //  but allow unselecting by dragging out of selected region
  if (firstCell && lastCell)
  {
    if (!mStartSelectedCell)
    {
      // We are starting a new block, so select the first cell
      result = SelectCellElement(firstCell);
      if (NS_FAILED(result)) return result;
      mStartSelectedCell = do_QueryInterface(firstCell);
    }
    nsCOMPtr<nsIContent> lastCellContent = do_QueryInterface(lastCell);
    result = SelectBlockOfCells(mStartSelectedCell, lastCellContent);

    // This gets set to the cell at end of row/col, 
    //   but we need it to be the cell under cursor
    mEndSelectedCell = aCellContent;
    return result;
  }

#if 0
// This is a more efficient strategy that appends row to current selection,
//  but doesn't allow dragging OFF of an existing selection to unselect!
  do {
    // Loop through all cells in column or row
    result = tableLayout->GetCellDataAt(rowIndex, colIndex,
                                        getter_AddRefs(cellElement),
                                        curRowIndex, curColIndex,
                                        rowSpan, colSpan,
                                        actualRowSpan, actualColSpan,
                                        isSelected);
    if (NS_FAILED(result)) return result;
    // We're done when cell is not found
    if (!cellElement) break;


    // Check spans else we infinitely loop
    NS_ASSERTION(actualColSpan, "actualColSpan is 0!");
    NS_ASSERTION(actualRowSpan, "actualRowSpan is 0!");
    
    // Skip cells that are already selected or span from outside our region
    if (!isSelected && rowIndex == curRowIndex && colIndex == curColIndex)
    {
      result = SelectCellElement(cellElement);
      if (NS_FAILED(result)) return result;
    }
    // Move to next row or column in cellmap, skipping spanned locations
    if (aTarget == nsISelectionPrivate::TABLESELECTION_ROW)
      colIndex += actualColSpan;
    else
      rowIndex += actualRowSpan;
  }
  while (cellElement);
#endif

  return NS_OK;
}

nsresult 
nsSelection::GetFirstCellNodeInRange(nsIDOMRange *aRange, nsIDOMNode **aCellNode)
{
  if (!aRange || !aCellNode) return NS_ERROR_NULL_POINTER;

  *aCellNode = nsnull;

  nsCOMPtr<nsIDOMNode> startParent;
  nsresult result = aRange->GetStartContainer(getter_AddRefs(startParent));
  if (NS_FAILED(result))
    return result;
  if (!startParent)
    return NS_ERROR_FAILURE;

  PRInt32 offset;
  result = aRange->GetStartOffset(&offset);
  if (NS_FAILED(result))
    return result;

  nsCOMPtr<nsIContent> parentContent = do_QueryInterface(startParent);
  nsCOMPtr<nsIContent> childContent = parentContent->GetChildAt(offset);
  if (!childContent)
    return NS_ERROR_NULL_POINTER;
  // Don't return node if not a cell
  if (!IsCell(childContent)) return NS_OK;

  nsCOMPtr<nsIDOMNode> childNode = do_QueryInterface(childContent);
  if (childNode)
  {
    *aCellNode = childNode;
    NS_ADDREF(*aCellNode);
  }
  return NS_OK;
}

nsresult 
nsSelection::GetFirstSelectedCellAndRange(nsIDOMNode **aCell, nsIDOMRange **aRange)
{
  if (!aCell) return NS_ERROR_NULL_POINTER;
  *aCell = nsnull;

  // aRange is optional
  if (aRange)
    *aRange = nsnull;

  nsCOMPtr<nsIDOMRange> firstRange;
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  nsresult result = mDomSelections[index]->GetRangeAt(0, getter_AddRefs(firstRange));
  if (NS_FAILED(result)) return result;
  if (!firstRange) return NS_ERROR_FAILURE;

  nsCOMPtr<nsIDOMNode> cellNode;
  result = GetFirstCellNodeInRange(firstRange, getter_AddRefs(cellNode));
  if (NS_FAILED(result)) return result;
  if (!cellNode) return NS_OK;

  *aCell = cellNode;
  NS_ADDREF(*aCell);
  if (aRange)
  {
    *aRange = firstRange;
    NS_ADDREF(*aRange);
  }

  // Setup for next cell
  mSelectedCellIndex = 1;

  return NS_OK;
}

nsresult
nsSelection::GetNextSelectedCellAndRange(nsIDOMNode **aCell, nsIDOMRange **aRange)
{
  if (!aCell) return NS_ERROR_NULL_POINTER;
  *aCell = nsnull;

  // aRange is optional
  if (aRange)
    *aRange = nsnull;

  PRInt32 rangeCount;
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  nsresult result = mDomSelections[index]->GetRangeCount(&rangeCount);
  if (NS_FAILED(result)) return result;

  // Don't even try if index exceeds range count
  if (mSelectedCellIndex >= rangeCount) 
  {
    // Should we reset index? 
    // Maybe better to force recalling GetFirstSelectedCell()
    //mSelectedCellIndex = 0;
    return NS_OK;
  }

  // Get first node in next range of selection - test if it's a cell
  nsCOMPtr<nsIDOMRange> range;
  result = mDomSelections[index]->GetRangeAt(mSelectedCellIndex, getter_AddRefs(range));
  if (NS_FAILED(result)) return result;
  if (!range) return NS_ERROR_FAILURE;

  nsCOMPtr<nsIDOMNode> cellNode;
  result = GetFirstCellNodeInRange(range, getter_AddRefs(cellNode));
  if (NS_FAILED(result)) return result;
  // No cell in selection range
  if (!cellNode) return NS_OK;

  *aCell = cellNode;
  NS_ADDREF(*aCell);
  if (aRange)
  {
    *aRange = range;
    NS_ADDREF(*aRange);
  }

  // Setup for next cell
  mSelectedCellIndex++;

  return NS_OK;
}

nsresult
nsSelection::GetCellIndexes(nsIContent *aCell, PRInt32 &aRowIndex, PRInt32 &aColIndex)
{
  if (!aCell) return NS_ERROR_NULL_POINTER;

  aColIndex=0; // initialize out params
  aRowIndex=0;

  nsITableCellLayout *cellLayoutObject = GetCellLayout(aCell);
  if (!cellLayoutObject)  return NS_ERROR_FAILURE;
  return cellLayoutObject->GetCellIndexes(aRowIndex, aColIndex);
}

PRBool 
nsSelection::IsInSameTable(nsIContent *aContent1, nsIContent *aContent2, nsIContent **aTable)
{
  if (!aContent1 || !aContent2) return PR_FALSE;
  
  // aTable is optional:
  if(aTable) *aTable = nsnull;
  
  nsCOMPtr<nsIContent> tableNode1;
  nsCOMPtr<nsIContent> tableNode2;

  nsresult result = GetParentTable(aContent1, getter_AddRefs(tableNode1));
  if (NS_FAILED(result)) return PR_FALSE;
  result = GetParentTable(aContent2, getter_AddRefs(tableNode2));
  if (NS_FAILED(result)) return PR_FALSE;

  // Must be in the same table
  if (tableNode1 && (tableNode1 == tableNode2))
  {
    if (aTable)
    {
      *aTable = tableNode1;
      NS_ADDREF(*aTable);
    }
    return PR_TRUE;;
  }
  return PR_FALSE;
}

nsresult
nsSelection::GetParentTable(nsIContent *aCell, nsIContent **aTable)
{
  if (!aCell || !aTable) {
    return NS_ERROR_NULL_POINTER;
  }

  for (nsIContent* parent = aCell->GetParent(); parent;
       parent = parent->GetParent()) {
    if (parent->Tag() == nsHTMLAtoms::table &&
        parent->IsContentOfType(nsIContent::eHTML)) {
      *aTable = parent;
      NS_ADDREF(*aTable);

      return NS_OK;
    }
  }

  return NS_OK;
}

nsresult
nsSelection::SelectCellElement(nsIDOMElement *aCellElement)
{
  nsCOMPtr<nsIContent> cellContent = do_QueryInterface(aCellElement);

  if (!cellContent) {
    return NS_ERROR_FAILURE;
  }

  nsIContent *parent = cellContent->GetParent();
  nsCOMPtr<nsIDOMNode> parentNode(do_QueryInterface(parent));
  if (!parentNode) {
    return NS_ERROR_FAILURE;
  }

  // Get child offset
  PRInt32 offset = parent->IndexOf(cellContent);

  return CreateAndAddRange(parentNode, offset);
}

nsresult
nsTypedSelection::getTableCellLocationFromRange(nsIDOMRange *aRange, PRInt32 *aSelectionType, PRInt32 *aRow, PRInt32 *aCol)
{
  if (!aRange || !aSelectionType || !aRow || !aCol)
    return NS_ERROR_NULL_POINTER;

  *aSelectionType = nsISelectionPrivate::TABLESELECTION_NONE;
  *aRow = 0;
  *aCol = 0;

  // Must have access to frame selection to get cell info
  if (!mFrameSelection) return NS_OK;

  nsresult result = GetTableSelectionType(aRange, aSelectionType);
  if (NS_FAILED(result)) return result;
  
  // Don't fail if range does not point to a single table cell,
  //  let aSelectionType tell user if we don't have a cell
  if (*aSelectionType  != nsISelectionPrivate::TABLESELECTION_CELL)
    return NS_OK;

  // Get the child content (the cell) pointed to by starting node of range
  // We do minimal checking since GetTableSelectionType assures
  //   us that this really is a table cell
  nsCOMPtr<nsIDOMNode> startNode;
  result = aRange->GetStartContainer(getter_AddRefs(startNode));
  if (NS_FAILED(result))
    return result;

  nsCOMPtr<nsIContent> content(do_QueryInterface(startNode));
  if (!content)
    return NS_ERROR_FAILURE;
  PRInt32 startOffset;
  result = aRange->GetStartOffset(&startOffset);
  if (NS_FAILED(result))
    return result;

  nsIContent *child = content->GetChildAt(startOffset);
  if (!child)
    return NS_ERROR_FAILURE;

  //Note: This is a non-ref-counted pointer to the frame
  nsITableCellLayout *cellLayout = mFrameSelection->GetCellLayout(child);
  if (NS_FAILED(result))
    return result;
  if (!cellLayout)
    return NS_ERROR_FAILURE;

  return cellLayout->GetCellIndexes(*aRow, *aCol);
}

nsresult
nsTypedSelection::addTableCellRange(nsIDOMRange *aRange, PRBool *aDidAddRange)
{
  if (!aDidAddRange)
    return NS_ERROR_NULL_POINTER;

  *aDidAddRange = PR_FALSE;

  if (!mFrameSelection)
    return NS_OK;

  if (!aRange)
    return NS_ERROR_NULL_POINTER;

  nsresult result;

  // Get if we are adding a cell selection and the row, col of cell if we are
  PRInt32 newRow, newCol, tableMode;
  result = getTableCellLocationFromRange(aRange, &tableMode, &newRow, &newCol);
  if (NS_FAILED(result)) return result;
  
  // If not adding a cell range, we are done here
  if (tableMode != nsISelectionPrivate::TABLESELECTION_CELL)
  {
    mFrameSelection->mSelectingTableCellMode = tableMode;
    // Don't fail if range isn't a selected cell, aDidAddRange tells caller if we didn't proceed
    return NS_OK;
  }
  
  // Set frame selection mode only if not already set to a table mode
  //  so we don't loose the select row and column flags (not detected by getTableCellLocation)
  if (mFrameSelection->mSelectingTableCellMode == TABLESELECTION_NONE)
    mFrameSelection->mSelectingTableCellMode = tableMode;

  PRInt32 count = mRangeArray.Count();

  if (count > 0)
  {
    // Adding a cell range to existing list of cell ranges
    PRInt32 index;
    PRInt32 row, col;
    // Insert range at appropriate location
    for (index = 0; index < count; index++)
    {
      nsIDOMRange* range = mRangeArray[index];
      if (!range) return NS_ERROR_FAILURE;

      PRInt32 selectionMode;
      result = getTableCellLocationFromRange(range, &selectionMode, &row, &col);
      if (NS_FAILED(result)) return result;

      // Don't proceed if range not a table cell
      if (selectionMode != nsISelectionPrivate::TABLESELECTION_CELL)
        return NS_OK;

      if (row > newRow ||
          (row == newRow && col > newCol))
      {
        // Existing selected cell is after cell to add,
        //  so insert at this index
        *aDidAddRange = mRangeArray.InsertObjectAt(aRange, index);
        return (*aDidAddRange) ? NS_OK : NS_ERROR_FAILURE;
      }
    }          
  }
  // If here, we are adding a selected cell range 
  //   to end of range array or it's the first selected range 
  *aDidAddRange = mRangeArray.AppendObject(aRange);
  return (*aDidAddRange) ? NS_OK : NS_ERROR_FAILURE;
}

//TODO: Figure out TABLESELECTION_COLUMN and TABLESELECTION_ALLCELLS
NS_IMETHODIMP
nsTypedSelection::GetTableSelectionType(nsIDOMRange* aRange, PRInt32* aTableSelectionType)
{
  if (!aRange || !aTableSelectionType)
    return NS_ERROR_NULL_POINTER;
  
  *aTableSelectionType = nsISelectionPrivate::TABLESELECTION_NONE;
 
  // Must have access to frame selection to get cell info
  if(!mFrameSelection) return NS_OK;

  nsCOMPtr<nsIDOMNode> startNode;
  nsresult result = aRange->GetStartContainer(getter_AddRefs(startNode));
  if (NS_FAILED(result)) return result;
  if (!startNode) return NS_ERROR_FAILURE;
  
  nsCOMPtr<nsIDOMNode> endNode;
  result = aRange->GetEndContainer(getter_AddRefs(endNode));
  if (NS_FAILED(result)) return result;
  if (!endNode) return NS_ERROR_FAILURE;

  // Not a single selected node
  if (startNode != endNode) return NS_OK;

  nsCOMPtr<nsIContent> content = do_QueryInterface(startNode);
  if (!content) return NS_ERROR_FAILURE;

  // if we simply cannot have children, return NS_OK as a non-failing,
  // non-completing case for table selection
  if (!content->CanContainChildren())
    return NS_OK; //got to be a text node, definately not a table row/cell
  
  PRInt32 startOffset;
  PRInt32 endOffset;
  result = aRange->GetEndOffset(&endOffset);
  if (NS_FAILED(result)) return result;
  result = aRange->GetStartOffset(&startOffset);
  if (NS_FAILED(result)) return result;

  // Not a single selected node
  if ((endOffset - startOffset) != 1)
    return NS_OK;

  if (!content->IsContentOfType(nsIContent::eHTML)) {
    return NS_OK;
  }

  nsIAtom *tag = content->Tag();

  if (tag == nsHTMLAtoms::tr)
  {
    *aTableSelectionType = nsISelectionPrivate::TABLESELECTION_CELL;
  }
  else //check to see if we are selecting a table or row (column and all cells not done yet)
  {
    nsIContent *child = content->GetChildAt(startOffset);
    if (!child)
      return NS_ERROR_FAILURE;

    tag = child->Tag();

    if (tag == nsHTMLAtoms::table)
      *aTableSelectionType = nsISelectionPrivate::TABLESELECTION_TABLE;
    else if (tag == nsHTMLAtoms::tr)
      *aTableSelectionType = nsISelectionPrivate::TABLESELECTION_ROW;
  }

  return result;
}

nsresult
nsSelection::CreateAndAddRange(nsIDOMNode *aParentNode, PRInt32 aOffset)
{
  if (!aParentNode) return NS_ERROR_NULL_POINTER;
  nsCOMPtr<nsIDOMRange> range;
  NS_NewRange(getter_AddRefs(range));
  if (!range) return NS_ERROR_OUT_OF_MEMORY;

  // Set range around child at given offset
  nsresult result = range->SetStart(aParentNode, aOffset);
  if (NS_FAILED(result)) return result;
  result = range->SetEnd(aParentNode, aOffset+1);
  if (NS_FAILED(result)) return result;
  
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  return mDomSelections[index]->AddRange(range);
}

// End of Table Selection

NS_IMETHODIMP
nsSelection::AdjustOffsetsFromStyle(nsIFrame *aFrame, PRBool *changeSelection,
      nsIContent** outContent, PRInt32* outStartOffset, PRInt32* outEndOffset)
{
  
  *changeSelection = PR_FALSE;
  *outContent = nsnull;
  
  nsresult  rv;  
  nsIFrame*   selectAllFrame;
  rv = FrameOrParentHasSpecialSelectionStyle(aFrame, NS_STYLE_USER_SELECT_ALL, &selectAllFrame);
  if (NS_FAILED(rv)) return rv;
  
  if (!selectAllFrame)
    return NS_OK;
  
  nsIContent* selectAllContent = selectAllFrame->GetContent();
  if (selectAllContent)
  {
    nsCOMPtr<nsIContent> parentContent = selectAllContent->GetParent();
    if (parentContent)
    {
      PRInt32 startOffset = parentContent->IndexOf(selectAllContent);

      if (startOffset < 0)
      {
        // hrmm, this is probably anonymous content. Let's go up another level
        // do we need to do this if we get the right frameSelection to start with?
        nsCOMPtr<nsIContent> superParent = parentContent->GetParent();
        if (superParent)
        {
          PRInt32 superStartOffset = superParent->IndexOf(parentContent);
          if (superStartOffset < 0)
            return NS_ERROR_FAILURE;    // give up
        
          parentContent = superParent;
          startOffset = superStartOffset;
        }
      }
      
      NS_IF_ADDREF(*outContent = parentContent);

      *outStartOffset = startOffset;
      *outEndOffset = startOffset + 1;

      *changeSelection = PR_TRUE;
    }    
  }

  return NS_OK;
}


NS_IMETHODIMP
nsSelection::SetHint(HINT aHintRight)
{
  mHint = aHintRight;
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::GetHint(HINT *aHintRight)
{
  *aHintRight = mHint;
  return NS_OK; 
}


//END nsIFrameSelection methods


#ifdef XP_MAC
#pragma mark -
#endif

//BEGIN nsISelection interface implementations



NS_IMETHODIMP
nsSelection::DeleteFromDocument()
{
  nsresult res;

  // If we're already collapsed, then set ourselves to include the
  // last item BEFORE the current range, rather than the range itself,
  // before we do the delete.
  PRBool isCollapsed;
  PRInt8 index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
  mDomSelections[index]->GetIsCollapsed( &isCollapsed);
  if (isCollapsed)
  {
    // If the offset is positive, then it's easy:
    if (mDomSelections[index]->FetchFocusOffset() > 0)
    {
      mDomSelections[index]->Extend(mDomSelections[index]->FetchFocusNode(), mDomSelections[index]->FetchFocusOffset() - 1);
    }
    else
    {
      // Otherwise it's harder, have to find the previous node
      printf("Sorry, don't know how to delete across frame boundaries yet\n");
      return NS_ERROR_NOT_IMPLEMENTED;
    }
  }

  // Get an iterator
  nsSelectionIterator iter(mDomSelections[index]);
  res = iter.First();
  if (NS_FAILED(res))
    return res;

  nsCOMPtr<nsIDOMRange> range;
  while (iter.IsDone())
  {
    res = iter.CurrentItem(NS_STATIC_CAST(nsIDOMRange**, getter_AddRefs(range)));
    if (NS_FAILED(res))
      return res;
    res = range->DeleteContents();
    if (NS_FAILED(res))
      return res;
    iter.Next();
  }

  // Collapse to the new location.
  // If we deleted one character, then we move back one element.
  // FIXME  We don't know how to do this past frame boundaries yet.
  if (isCollapsed)
    mDomSelections[index]->Collapse(mDomSelections[index]->FetchAnchorNode(), mDomSelections[index]->FetchAnchorOffset()-1);
  else if (mDomSelections[index]->FetchAnchorOffset() > 0)
    mDomSelections[index]->Collapse(mDomSelections[index]->FetchAnchorNode(), mDomSelections[index]->FetchAnchorOffset());
#ifdef DEBUG
  else
    printf("Don't know how to set selection back past frame boundary\n");
#endif

  return NS_OK;
}


NS_IMETHODIMP
nsSelection::SetDisplaySelection(PRInt16 aToggle)
{
  mDisplaySelection = aToggle;
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::GetDisplaySelection(PRInt16 *aToggle)
{
  if (!aToggle)
    return NS_ERROR_INVALID_ARG;
  *aToggle = mDisplaySelection;
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::SetDelayCaretOverExistingSelection(PRBool aDelay)
{
  mDelayCaretOverExistingSelection = aDelay;
  
  if (! aDelay)
    mDelayedMouseEventValid = PR_FALSE;

  return NS_OK;
}

NS_IMETHODIMP
nsSelection::GetDelayCaretOverExistingSelection(PRBool *aDelay)
{
  if (!aDelay)
    return NS_ERROR_NULL_POINTER;

  *aDelay =   mDelayCaretOverExistingSelection;

  return NS_OK;
}

NS_IMETHODIMP
nsSelection::SetDelayedCaretData(nsMouseEvent *aMouseEvent)
{
  if (aMouseEvent)
  {
    mDelayedMouseEventValid = PR_TRUE;
    mDelayedMouseEvent      = *aMouseEvent;

    // XXX: Hmmm, should we AddRef mDelayedMouseEvent->widget?
    //      Doing so might introduce a leak if things in the app
    //      are not released in the correct order though, so for now
    //      don't do anything.
  }
  else
    mDelayedMouseEventValid = PR_FALSE;

  return NS_OK;
}

NS_IMETHODIMP
nsSelection::GetDelayedCaretData(nsMouseEvent **aMouseEvent)
{
  if (!aMouseEvent)
    return NS_ERROR_NULL_POINTER;

  if (mDelayedMouseEventValid)
    *aMouseEvent = &mDelayedMouseEvent;
  else
    *aMouseEvent = 0;

  return NS_OK;
}

// Frame needs to get the limiting content node for parent node searches
NS_IMETHODIMP
nsSelection::GetLimiter(nsIContent **aLimiterContent)
{
  if (!aLimiterContent) return NS_ERROR_NULL_POINTER;
  *aLimiterContent = mLimiter;
  NS_IF_ADDREF(*aLimiterContent);

  return NS_OK;
}

NS_IMETHODIMP
nsSelection::SetMouseDoubleDown(PRBool aDoubleDown)
{
  mMouseDoubleDownState = aDoubleDown;
  return NS_OK;
}

NS_IMETHODIMP
nsSelection::GetMouseDoubleDown(PRBool *aDoubleDown)
{
  *aDoubleDown = mMouseDoubleDownState;
  return NS_OK;
}
 
//END nsISelection interface implementations

#if 0
#pragma mark -
#endif

// nsTypedSelection implementation

// note: this can return a nil anchor node

nsTypedSelection::nsTypedSelection(nsSelection *aList)
{
  mFrameSelection = aList;
  mFixupState = PR_FALSE;
  mDirection = eDirNext;
  mAutoScrollTimer = nsnull;
  mScrollEventPosted = PR_FALSE;
  mCachedOffsetForFrame = nsnull;
}


nsTypedSelection::nsTypedSelection()
{
  mFrameSelection = nsnull;
  mFixupState = PR_FALSE;
  mDirection = eDirNext;
  mAutoScrollTimer = nsnull;
  mScrollEventPosted = PR_FALSE;
  mCachedOffsetForFrame = nsnull;
}



nsTypedSelection::~nsTypedSelection()
{
  setAnchorFocusRange(-1);

  if (mAutoScrollTimer) {
    mAutoScrollTimer->Stop();
    NS_RELEASE(mAutoScrollTimer);
  }

  if (mEventQueue && mScrollEventPosted) {
    mEventQueue->RevokeEvents(this);
    mScrollEventPosted = PR_FALSE;
  }

  delete mCachedOffsetForFrame;
}


// QueryInterface implementation for nsRange
NS_INTERFACE_MAP_BEGIN(nsTypedSelection)
  NS_INTERFACE_MAP_ENTRY(nsISelection)
  NS_INTERFACE_MAP_ENTRY(nsISelectionPrivate)
  NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsISelection)
  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO(Selection)
NS_INTERFACE_MAP_END


NS_IMPL_ADDREF(nsTypedSelection)
NS_IMPL_RELEASE(nsTypedSelection)


NS_IMETHODIMP
nsTypedSelection::SetPresShell(nsIPresShell *aPresShell)
{
  mPresShellWeak = do_GetWeakReference(aPresShell);
  return NS_OK;
}



NS_IMETHODIMP
nsTypedSelection::GetAnchorNode(nsIDOMNode** aAnchorNode)
{
  if (!aAnchorNode)
    return NS_ERROR_NULL_POINTER;
  *aAnchorNode = nsnull;
  if(!mAnchorFocusRange)
    return NS_OK;
   
  nsresult result;
  if (GetDirection() == eDirNext){
    result = mAnchorFocusRange->GetStartContainer(aAnchorNode);
  }
  else{
    result = mAnchorFocusRange->GetEndContainer(aAnchorNode);
  }
  return result;
}

NS_IMETHODIMP
nsTypedSelection::GetAnchorOffset(PRInt32* aAnchorOffset)
{
  if (!aAnchorOffset)
    return NS_ERROR_NULL_POINTER;
  *aAnchorOffset = nsnull;
  if(!mAnchorFocusRange)
    return NS_OK;

  nsresult result;
  if (GetDirection() == eDirNext){
    result = mAnchorFocusRange->GetStartOffset(aAnchorOffset);
  }
  else{
    result = mAnchorFocusRange->GetEndOffset(aAnchorOffset);
  }
  return result;
}

// note: this can return a nil focus node
NS_IMETHODIMP
nsTypedSelection::GetFocusNode(nsIDOMNode** aFocusNode)
{
  if (!aFocusNode)
    return NS_ERROR_NULL_POINTER;
  *aFocusNode = nsnull;
  if(!mAnchorFocusRange)
    return NS_OK;

  nsresult result;
  if (GetDirection() == eDirNext){
    result = mAnchorFocusRange->GetEndContainer(aFocusNode);
  }
  else{
    result = mAnchorFocusRange->GetStartContainer(aFocusNode);
  }

  return result;
}

NS_IMETHODIMP nsTypedSelection::GetFocusOffset(PRInt32* aFocusOffset)
{
  if (!aFocusOffset)
    return NS_ERROR_NULL_POINTER;
  *aFocusOffset = nsnull;
  if(!mAnchorFocusRange)
    return NS_OK;

   nsresult result;
  if (GetDirection() == eDirNext){
    result = mAnchorFocusRange->GetEndOffset(aFocusOffset);
  }
  else{
    result = mAnchorFocusRange->GetStartOffset(aFocusOffset);
  }
  return result;
}


void nsTypedSelection::setAnchorFocusRange(PRInt32 indx)
{
  if (indx >= mRangeArray.Count())
    return;
  if (indx < 0) //release all
  {
    mAnchorFocusRange = nsnull;
  }
  else{
    mAnchorFocusRange = mRangeArray[indx];
  }
}



nsIDOMNode*
nsTypedSelection::FetchAnchorNode()
{  //where did the selection begin
  nsCOMPtr<nsIDOMNode>returnval;
  GetAnchorNode(getter_AddRefs(returnval));//this queries
  return returnval;
}//at end it will release, no addreff was called



PRInt32
nsTypedSelection::FetchAnchorOffset()
{
  PRInt32 returnval;
  if (NS_SUCCEEDED(GetAnchorOffset(&returnval)))//this queries
    return returnval;
  return 0;
}



nsIDOMNode*
nsTypedSelection::FetchOriginalAnchorNode()  //where did the ORIGINAL selection begin
{
  nsCOMPtr<nsIDOMNode>returnval;
  PRInt32 unused;
  GetOriginalAnchorPoint(getter_AddRefs(returnval),  &unused);//this queries
  return returnval;
}



PRInt32
nsTypedSelection::FetchOriginalAnchorOffset()
{
  nsCOMPtr<nsIDOMNode>unused;
  PRInt32 returnval;
  if (NS_SUCCEEDED(GetOriginalAnchorPoint(getter_AddRefs(unused), &returnval)))//this queries
    return returnval;
  return NS_OK;
}



nsIDOMNode*
nsTypedSelection::FetchFocusNode()
{   //where is the carret
  nsCOMPtr<nsIDOMNode>returnval;
  GetFocusNode(getter_AddRefs(returnval));//this queries
  return returnval;
}//at end it will release, no addreff was called



PRInt32
nsTypedSelection::FetchFocusOffset()
{
  PRInt32 returnval;
  if (NS_SUCCEEDED(GetFocusOffset(&returnval)))//this queries
    return returnval;
  return NS_OK;
}



nsIDOMNode*
nsTypedSelection::FetchStartParent(nsIDOMRange *aRange)   //skip all the com stuff and give me the start/end
{
  if (!aRange)
    return nsnull;
  nsCOMPtr<nsIDOMNode> returnval;
  aRange->GetStartContainer(getter_AddRefs(returnval));
  return returnval;
}



PRInt32
nsTypedSelection::FetchStartOffset(nsIDOMRange *aRange)
{
  if (!aRange)
    return nsnull;
  PRInt32 returnval;
  if (NS_SUCCEEDED(aRange->GetStartOffset(&returnval)))
    return returnval;
  return 0;
}



nsIDOMNode*
nsTypedSelection::FetchEndParent(nsIDOMRange *aRange)     //skip all the com stuff and give me the start/end
{
  if (!aRange)
    return nsnull;
  nsCOMPtr<nsIDOMNode> returnval;
  aRange->GetEndContainer(getter_AddRefs(returnval));
  return returnval;
}



PRInt32
nsTypedSelection::FetchEndOffset(nsIDOMRange *aRange)
{
  if (!aRange)
    return nsnull;
  PRInt32 returnval;
  if (NS_SUCCEEDED(aRange->GetEndOffset(&returnval)))
    return returnval;
  return 0;
}

nsresult
nsTypedSelection::AddItem(nsIDOMRange *aItem)
{
  if (!aItem)
    return NS_ERROR_NULL_POINTER;
  return mRangeArray.AppendObject(aItem) ? NS_OK : NS_ERROR_FAILURE;
}



nsresult
nsTypedSelection::RemoveItem(nsIDOMRange *aItem)
{
  if (!aItem)
    return NS_ERROR_NULL_POINTER;
  mRangeArray.RemoveObject(aItem);
  return  NS_OK;
}



nsresult
nsTypedSelection::Clear(nsIPresContext* aPresContext)
{
  setAnchorFocusRange(-1);
  // Get an iterator
  while (PR_TRUE)
  {
    PRInt32 cnt = mRangeArray.Count();
    if (cnt == 0)
      break;
    nsCOMPtr<nsIDOMRange> range = mRangeArray[0];
    mRangeArray.RemoveObjectAt(0);
    selectFrames(aPresContext, range, 0);
  }
  // Reset direction so for more dependable table selection range handling
  SetDirection(eDirNext);
  return NS_OK;
}

//utility method to get the primary frame of node or use the offset to get frame of child node

#if 0
NS_IMETHODIMP
nsTypedSelection::GetPrimaryFrameForRangeEndpoint(nsIDOMNode *aNode, PRInt32 aOffset, PRBool aIsEndNode, nsIFrame **aReturnFrame)
{
  if (!aNode || !aReturnFrame)
    return NS_ERROR_NULL_POINTER;
  
  if (aOffset < 0)
    return NS_ERROR_FAILURE;

  *aReturnFrame = 0;
  
  nsresult  result = NS_OK;
  
  nsCOMPtr<nsIDOMNode> node = aNode;

  if (!node)
    return NS_ERROR_NULL_POINTER;
  
  nsCOMPtr<nsIContent> content = do_QueryInterface(node, &result);

  if (NS_FAILED(result))
    return result;

  if (!content)
    return NS_ERROR_NULL_POINTER;
  
  if (content->CanContainChildren())
  {
    if (aIsEndNode)
      aOffset--;

    if (aOffset >= 0)
    {
      nsIContent *child = content->GetChildAt(aOffset);
      if (!child) //out of bounds?
        return NS_ERROR_FAILURE;

      content = child; // releases the focusnode
    }
  }
  result = mFrameSelection->GetTracker()->GetPrimaryFrameFor(content,aReturnFrame);
  return result;
}
#endif


NS_IMETHODIMP
nsTypedSelection::GetPrimaryFrameForAnchorNode(nsIFrame **aReturnFrame)
{
  if (!aReturnFrame)
    return NS_ERROR_NULL_POINTER;
  
  PRInt32 frameOffset = 0;
  *aReturnFrame = 0;
  nsCOMPtr<nsIContent> content = do_QueryInterface(FetchAnchorNode());
  if (content && mFrameSelection)
  {
    nsIFrameSelection::HINT hint;
    mFrameSelection->GetHint(&hint);
    return mFrameSelection->GetFrameForNodeOffset(content, FetchAnchorOffset(),hint,aReturnFrame, &frameOffset);
  }
  return NS_ERROR_FAILURE;
}

NS_IMETHODIMP
nsTypedSelection::GetPrimaryFrameForFocusNode(nsIFrame **aReturnFrame, PRInt32 *aOffsetUsed)
{
  if (!aReturnFrame)
    return NS_ERROR_NULL_POINTER;
  
  PRInt32 frameOffset = 0;
  *aReturnFrame = 0;
  if (!aOffsetUsed)
    aOffsetUsed = &frameOffset;
    

  nsCOMPtr<nsIContent> content = do_QueryInterface(FetchFocusNode());
  if (content && mFrameSelection)
  {
    nsIFrameSelection::HINT hint;
    mFrameSelection->GetHint(&hint);
    return mFrameSelection->GetFrameForNodeOffset(content, FetchFocusOffset(),hint,aReturnFrame, aOffsetUsed);
  }
  return NS_ERROR_FAILURE;
}



//select all content children of aContent
NS_IMETHODIMP
nsTypedSelection::selectFrames(nsIPresContext* aPresContext,
                             nsIContentIterator *aInnerIter,
                             nsIContent *aContent,
                             nsIDOMRange *aRange,
                             nsIPresShell *aPresShell,
                             PRBool aFlags)
{
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  nsresult result;
  if (!aInnerIter)
    return NS_ERROR_NULL_POINTER;
#ifdef USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
  nsCOMPtr<nsIGeneratedContentIterator> genericiter = do_QueryInterface(aInnerIter);
  if (genericiter && aPresShell)
  {
    result = genericiter->Init(aPresShell,aContent);
  }
  else
#endif // USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
    result = aInnerIter->Init(aContent);
  nsIFrame *frame;
  if (NS_SUCCEEDED(result))
  {
    // First select frame of content passed in
    result = mFrameSelection->GetTracker()->GetPrimaryFrameFor(aContent, &frame);
    if (NS_SUCCEEDED(result) && frame)
    {
      //NOTE: eSpreadDown is now IGNORED. Selected state is set only for given frame
      frame->SetSelected(aPresContext, nsnull, aFlags, eSpreadDown);
#ifndef OLD_TABLE_SELECTION
      PRBool tablesel;
      mFrameSelection->GetTableCellSelection(&tablesel);
      if (tablesel)
      {
        nsITableCellLayout *tcl = nsnull;
        CallQueryInterface(frame, &tcl);
        if (tcl)
        {
          return NS_OK;
        }
      }
#endif //OLD_TABLE_SELECTION
    }
    // Now iterated through the child frames and set them
    while (!aInnerIter->IsDone())
    {
      nsIContent *innercontent = aInnerIter->GetCurrentNode();

      result = mFrameSelection->GetTracker()->GetPrimaryFrameFor(innercontent, &frame);
      if (NS_SUCCEEDED(result) && frame)
      {
        //NOTE: eSpreadDown is now IGNORED. Selected state is set only
        //for given frame

        //spread from here to hit all frames in flow
        frame->SetSelected(aPresContext, nsnull,aFlags,eSpreadDown);
        nsRect frameRect = frame->GetRect();

        //if a rect is 0 height/width then try to notify next
        //available in flow of selection status.
        while (!frameRect.width || !frameRect.height)
        {
          //try to notify next in flow that its content is selected.
          if (NS_SUCCEEDED(frame->GetNextInFlow(&frame)) && frame)
          {
            frameRect = frame->GetRect();
            frame->SetSelected(aPresContext, nsnull,aFlags,eSpreadDown);
          }
          else
            break;
        }
        //if the frame is splittable and this frame is 0,0 then set
        //the next in flow frame to be selected also
      }

      aInnerIter->Next();
    }

#if 0
    result = mFrameSelection->GetTracker()->GetPrimaryFrameFor(content, &frame);
    if (NS_SUCCEEDED(result) && frame)
      frame->SetSelected(aRange,aFlags,eSpreadDown);//spread from here to hit all frames in flow
#endif

    return NS_OK;
  }

  return NS_ERROR_FAILURE;
}



//the idea of this helper method is to select, deselect "top to bottom" traversing through the frames
NS_IMETHODIMP
nsTypedSelection::selectFrames(nsIPresContext* aPresContext, nsIDOMRange *aRange, PRBool aFlags)
{
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  if (!aRange || !aPresContext) 
    return NS_ERROR_NULL_POINTER;

  nsresult result;
  nsCOMPtr<nsIContentIterator> iter = do_CreateInstance(
#ifdef USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
                                              kCGenSubtreeIteratorCID,
#else
                                              kCSubtreeIteratorCID,
#endif // USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
                                              &result);
  if (NS_FAILED(result))
    return result;

  nsCOMPtr<nsIContentIterator> inneriter = do_CreateInstance(
#ifdef USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
                                              kCGenContentIteratorCID,
#else
                                              kCContentIteratorCID,
#endif // USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
                                              &result);

  if ((NS_SUCCEEDED(result)) && iter && inneriter)
  {
    nsIPresShell *presShell = aPresContext->GetPresShell();
#ifdef USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
    nsCOMPtr<nsIGeneratedContentIterator> genericiter = do_QueryInterface(iter);
    if (genericiter && presShell)
      result = genericiter->Init(presShell,aRange);
    else
#endif // USE_SELECTION_GENERATED_CONTENT_ITERATOR_CODE
      result = iter->Init(aRange);

    // loop through the content iterator for each content node
    // for each text node:
    // get the frame for the content, and from it the style context
    // ask the style context about the property
    nsCOMPtr<nsIContent> content;
    nsIFrame *frame;
//we must call first one explicitly
    content = do_QueryInterface(FetchStartParent(aRange), &result);
    if (NS_FAILED(result) || !content)
      return result;

    if (!content->CanContainChildren())
    {
      result = mFrameSelection->GetTracker()->GetPrimaryFrameFor(content, &frame);
      if (NS_SUCCEEDED(result) && frame)
        frame->SetSelected(aPresContext, aRange,aFlags,eSpreadDown);//spread from here to hit all frames in flow
    }
//end start content
    iter->First();

    while (!iter->IsDone())
    {
      content = iter->GetCurrentNode();

      selectFrames(aPresContext, inneriter, content, aRange, presShell,aFlags);

      iter->Next();
    }
//we must now do the last one  if it is not the same as the first
    if (FetchEndParent(aRange) != FetchStartParent(aRange))
    {
      content = do_QueryInterface(FetchEndParent(aRange), &result);
      if (NS_FAILED(result) || !content)
        return result;

      if (!content->CanContainChildren())
      {
        result = mFrameSelection->GetTracker()->GetPrimaryFrameFor(content, &frame);
        if (NS_SUCCEEDED(result) && frame)
           frame->SetSelected(aPresContext, aRange,aFlags,eSpreadDown);//spread from here to hit all frames in flow
      }
    }
//end end parent
  }
  return result;
}


NS_IMETHODIMP
nsTypedSelection::LookUpSelection(nsIContent *aContent, PRInt32 aContentOffset, PRInt32 aContentLength,
                           SelectionDetails **aReturnDetails, SelectionType aType, PRBool aSlowCheck)
{
  PRInt32 cnt;
  nsresult rv = GetRangeCount(&cnt);
  if (NS_FAILED(rv)) 
    return rv;
  PRInt32 i;

  nsCOMPtr<nsIDOMNode> passedInNode;
  passedInNode = do_QueryInterface(aContent);
  if (!passedInNode)
    return NS_ERROR_FAILURE;

  SelectionDetails *details = nsnull;
  SelectionDetails *newDetails = details;

  for (i =0; i<cnt; i++){
    nsCOMPtr<nsIDOMRange> range = mRangeArray[i];
    if (range){
      nsCOMPtr<nsIDOMNode> startNode;
      nsCOMPtr<nsIDOMNode> endNode;
      PRInt32 startOffset;
      PRInt32 endOffset;
      range->GetStartContainer(getter_AddRefs(startNode));
      range->GetStartOffset(&startOffset);
      range->GetEndContainer(getter_AddRefs(endNode));
      range->GetEndOffset(&endOffset);
      if (passedInNode == startNode && passedInNode == endNode){
        if (startOffset < (aContentOffset + aContentLength)  &&
            endOffset > aContentOffset){
          if (!details){
            details = new SelectionDetails;

            newDetails = details;
          }
          else{
            newDetails->mNext = new SelectionDetails;
            newDetails = newDetails->mNext;
          }
          if (!newDetails)
            return NS_ERROR_OUT_OF_MEMORY;
          newDetails->mNext = nsnull;
          newDetails->mStart = PR_MAX(0,startOffset - aContentOffset);
          newDetails->mEnd = PR_MIN(aContentLength, endOffset - aContentOffset);
          newDetails->mType = aType;
        }
      }
      else if (passedInNode == startNode){ //are we at the beginning?
        if (startOffset < (aContentOffset + aContentLength)){
          if (!details){
            details = new SelectionDetails;
            newDetails = details;
          }
          else{
            newDetails->mNext = new SelectionDetails;
            newDetails = newDetails->mNext;
          }
          if (!newDetails)
            return NS_ERROR_OUT_OF_MEMORY;
          newDetails->mNext = nsnull;
          newDetails->mStart = PR_MAX(0,startOffset - aContentOffset);
          newDetails->mEnd = aContentLength;
          newDetails->mType = aType;
        }
      }
      else if (passedInNode == endNode){//are we at the end?
        if (endOffset > aContentOffset){
          if (!details){
            details = new SelectionDetails;
            newDetails = details;
          }
          else{
            newDetails->mNext = new SelectionDetails;
            newDetails = newDetails->mNext;
          }
          if (!newDetails)
            return NS_ERROR_OUT_OF_MEMORY;
          newDetails->mNext = nsnull;
          newDetails->mStart = 0;
          newDetails->mEnd = PR_MIN(aContentLength, endOffset - aContentOffset);
          newDetails->mType = aType;
        }
      }
      else { //then we MUST be completely selected! unless someone needs us to check to make sure with slowcheck

        if (cnt > 1 || aSlowCheck){ //if more than 1 selection or we need to do slow check see if farther than start or less than end.
          //we only have to look at start offset because anything else would have been in the range
          PRInt32 resultnum = ComparePoints(startNode, startOffset 
                                  ,passedInNode, aContentOffset);
          if (resultnum > 0)
            continue; 
          resultnum = ComparePoints(endNode, endOffset,
                              passedInNode, aContentOffset );
          if (resultnum <0)
            continue;
        }

        if (!details){
          details = new SelectionDetails;
          newDetails = details;
        }
        else{
          newDetails->mNext = new SelectionDetails;
          newDetails = newDetails->mNext;
        }
        if (!newDetails)
          return NS_ERROR_OUT_OF_MEMORY;
        newDetails->mNext = nsnull;
        newDetails->mStart = 0;
        newDetails->mEnd = aContentLength;
        newDetails->mType = aType;
     }
    }
    else
      continue;
  }
  if (*aReturnDetails && newDetails)
    newDetails->mNext = *aReturnDetails;
  if (details)
    *aReturnDetails = details;
  return NS_OK;
}

NS_IMETHODIMP
nsTypedSelection::Repaint(nsIPresContext* aPresContext)
{
  PRInt32 arrCount = mRangeArray.Count();

  if (arrCount < 1)
    return NS_OK;

  PRInt32 i;
  nsIDOMRange* range;
  
  for (i = 0; i < arrCount; i++)
  {
    range = mRangeArray[i];

    if (!range)
      return NS_ERROR_UNEXPECTED;

    nsresult rv = selectFrames(aPresContext, range, PR_TRUE);

    if (NS_FAILED(rv)) {
      return rv;
    }
  }

  return NS_OK;
}

NS_IMETHODIMP
nsTypedSelection::GetCanCacheFrameOffset(PRBool *aCanCacheFrameOffset)
{ 
  NS_ENSURE_ARG_POINTER(aCanCacheFrameOffset);

  if (mCachedOffsetForFrame)
    *aCanCacheFrameOffset = mCachedOffsetForFrame->mCanCacheFrameOffset;
  else
    *aCanCacheFrameOffset = PR_FALSE;

  return NS_OK;
}

NS_IMETHODIMP    
nsTypedSelection::SetCanCacheFrameOffset(PRBool aCanCacheFrameOffset)
{
  if (!mCachedOffsetForFrame) {
    mCachedOffsetForFrame = new CachedOffsetForFrame;
  }

  mCachedOffsetForFrame->mCanCacheFrameOffset = aCanCacheFrameOffset;

  // clean up cached frame when turn off cache
  // fix bug 207936
  if (!aCanCacheFrameOffset) {
    mCachedOffsetForFrame->mLastCaretFrame = nsnull;
  }

  return NS_OK;
}

NS_IMETHODIMP    
nsTypedSelection::GetCachedFrameOffset(nsIFrame *aFrame, PRInt32 inOffset, nsPoint& aPoint)
{
  if (!mCachedOffsetForFrame) {
    mCachedOffsetForFrame = new CachedOffsetForFrame;
  }

  if (mCachedOffsetForFrame->mCanCacheFrameOffset &&
      mCachedOffsetForFrame->mLastCaretFrame &&
      (aFrame == mCachedOffsetForFrame->mLastCaretFrame) &&
      (inOffset == mCachedOffsetForFrame->mLastContentOffset))
  {
     // get cached frame offset
     aPoint = mCachedOffsetForFrame->mCachedFrameOffset;
  } 
  else
  {
     // recalculate frame offset and cache it
     GetPointFromOffset(aFrame, inOffset, &aPoint);
     if (mCachedOffsetForFrame->mCanCacheFrameOffset) {
       mCachedOffsetForFrame->mCachedFrameOffset = aPoint;
       mCachedOffsetForFrame->mLastCaretFrame = aFrame;
       mCachedOffsetForFrame->mLastContentOffset = inOffset; 
     }
  }

  return NS_OK;
}

nsresult
nsTypedSelection::StartAutoScrollTimer(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint, PRUint32 aDelay)
{
  nsresult result;
  if (!mFrameSelection)
    return NS_OK;//nothing to do

  if (!mAutoScrollTimer)
  {
    result = NS_NewAutoScrollTimer(&mAutoScrollTimer);

    if (NS_FAILED(result))
      return result;

    if (!mAutoScrollTimer)
      return NS_ERROR_OUT_OF_MEMORY;

    result = mAutoScrollTimer->Init(mFrameSelection, this);

    if (NS_FAILED(result))
      return result;
  }

  result = mAutoScrollTimer->SetDelay(aDelay);

  if (NS_FAILED(result))
    return result;

  return DoAutoScroll(aPresContext, aFrame, aPoint);
}

nsresult
nsTypedSelection::StopAutoScrollTimer()
{
  if (mAutoScrollTimer)
    return mAutoScrollTimer->Stop();

  return NS_OK; 
}

nsresult
nsTypedSelection::GetViewAncestorOffset(nsIView *aView, nsIView *aAncestorView, nscoord *aXOffset, nscoord *aYOffset)
{
  // Note: A NULL aAncestorView pointer means that the caller wants
  //       the view's global offset.

  if (!aView || !aXOffset || !aYOffset)
    return NS_ERROR_FAILURE;

  *aXOffset = 0;
  *aYOffset = 0;

  for (nsIView* view = aView; view && view != aAncestorView;
       view = view->GetParent())
  {
    nsPoint pt = view->GetPosition();
    *aXOffset += pt.x;
    *aYOffset += pt.y;
  }

  return NS_OK;
}

nsresult
nsTypedSelection::GetClosestScrollableView(nsIView *aView, nsIScrollableView **aScrollableView)
{
  if (!aView || !aScrollableView)
    return NS_ERROR_FAILURE;

  *aScrollableView = 0;

  while (!*aScrollableView && aView)
  {
    CallQueryInterface(aView, aScrollableView);
    if (!*aScrollableView)
    {
      aView = aView->GetParent();
    }
  }

  return NS_OK;
}

nsresult
nsTypedSelection::ScrollPointIntoClipView(nsIPresContext *aPresContext, nsIView *aView, nsPoint& aPoint, PRBool *aDidScroll)
{
  nsresult result;

  if (!aPresContext || !aView || !aDidScroll)
    return NS_ERROR_NULL_POINTER;

  *aDidScroll = PR_FALSE;

  //
  // Get aView's scrollable view.
  //

  nsIScrollableView *scrollableView = 0;

  result = GetClosestScrollableView(aView, &scrollableView);

  if (NS_FAILED(result))
    return result;

  if (!scrollableView)
    return NS_OK; // Nothing to do!

  //
  // Get the clip view.
  //

  const nsIView *cView = 0;

  result = scrollableView->GetClipView(&cView);

  if (NS_FAILED(result))
    return result;

  //
  // Get the view that is being scrolled.
  //

  nsIView *scrolledView = 0;

  result = scrollableView->GetScrolledView(scrolledView);
  if (!cView)
    return NS_ERROR_FAILURE;
  
  //
  // Now walk up aView's hierarchy, this time keeping track of
  // the view offsets until you hit the scrolledView.
  //

  nsPoint viewOffset(0,0);

  result = GetViewAncestorOffset(aView, scrolledView, &viewOffset.x, &viewOffset.y);

  if (NS_FAILED(result))
    return result;

  //
  // See if aPoint is outside the clip view's boundaries.
  // If it is, scroll the view till it is inside the visible area!
  //

  nsRect bounds = cView->GetBounds();

  result = scrollableView->GetScrollPosition(bounds.x,bounds.y);

  if (NS_FAILED(result))
    return result;

  //
  // Calculate the amount we would have to scroll in
  // the vertical and horizontal directions to get the point
  // within the clip area.
  //

  nscoord dx = 0, dy = 0;
  nsPoint ePoint = aPoint;

  ePoint.x += viewOffset.x;
  ePoint.y += viewOffset.y;
  
  nscoord x1 = bounds.x;
  nscoord x2 = bounds.x + bounds.width;
  nscoord y1 = bounds.y;
  nscoord y2 = bounds.y + bounds.height;

  if (ePoint.x < x1)
    dx = ePoint.x - x1;
  else if (ePoint.x > x2)
    dx = ePoint.x - x2;
      
  if (ePoint.y < y1)
    dy = ePoint.y - y1;
  else if (ePoint.y > y2)
    dy = ePoint.y - y2;

  //
  // Now clip the scroll amounts so that we don't scroll
  // beyond the ends of the document.
  //

  nscoord scrollX = 0, scrollY = 0;
  nscoord docWidth = 0, docHeight = 0;

  result = scrollableView->GetScrollPosition(scrollX, scrollY);

  if (NS_SUCCEEDED(result))
    result = scrollableView->GetContainerSize(&docWidth, &docHeight);

  if (NS_SUCCEEDED(result))
  {
    if (dx < 0 && scrollX == 0)
      dx = 0;
    else if (dx > 0)
    {
      x1 = scrollX + dx + bounds.width;

      if (x1 > docWidth)
        dx -= x1 - docWidth;
    }


    if (dy < 0 && scrollY == 0)
      dy = 0;
    else if (dy > 0)
    {
      y1 = scrollY + dy + bounds.height;

      if (y1 > docHeight)
        dy -= y1 - docHeight;
    }

    //
    // Now scroll the view if neccessary.
    //

    if (dx != 0 || dy != 0)
    {
      // Make sure latest bits are available before we scroll them.
      aPresContext->GetViewManager()->Composite();

      // Now scroll the view!

      result = scrollableView->ScrollTo(scrollX + dx, scrollY + dy, NS_VMREFRESH_NO_SYNC);

      if (NS_FAILED(result))
        return result;

      nsPoint newPos;

      result = scrollableView->GetScrollPosition(newPos.x, newPos.y);

      if (NS_FAILED(result))
        return result;

      *aDidScroll = (bounds.x != newPos.x || bounds.y != newPos.y);
    }
  }

  return result;
}

nsresult
nsTypedSelection::ScrollPointIntoView(nsIPresContext *aPresContext, nsIView *aView, nsPoint& aPoint, PRBool aScrollParentViews, PRBool *aDidScroll)
{
  if (!aPresContext || !aView || !aDidScroll)
    return NS_ERROR_NULL_POINTER;

  nsresult result;

  *aDidScroll = PR_FALSE;

  //
  // Calculate the global offset of the view.
  //

  nsPoint globalOffset;

  result = GetViewAncestorOffset(aView, nsnull, &globalOffset.x, &globalOffset.y);

  if (NS_FAILED(result))
    return result;

  //
  // Convert aPoint into global coordinates so it is easier to map
  // into other views.
  //

  nsPoint globalPoint = aPoint + globalOffset;

  //
  // Scroll the point into the visible rect of the closest
  // scrollable view.
  //
  result = ScrollPointIntoClipView(aPresContext, aView, aPoint, aDidScroll);

  if (NS_FAILED(result))
    return result;

  //
  // Now scroll the parent scrollable views.
  //

  if (aScrollParentViews)
  {
    //
    // Find aView's parent scrollable view.
    //

    nsIScrollableView *scrollableView = 0;

    result = GetClosestScrollableView(aView, &scrollableView);

    if (NS_FAILED(result))
      return result;

    if (scrollableView)
    {
      //
      // Convert scrollableView to nsIView.
      //

      nsIView *scrolledView = 0;
      nsIView *view = 0;

      CallQueryInterface(scrollableView, &view);

      if (view)
      {
        //
        // Now get the scrollableView's parent, then search for it's
        // closest scrollable view.
        //

        view = view->GetParent();

        while (view)
        {
          result = GetClosestScrollableView(view, &scrollableView);

          if (NS_FAILED(result))
            return result;

          if (!scrollableView)
            break;

          scrolledView = 0;
          result = scrollableView->GetScrolledView(scrolledView);
          
          if (NS_FAILED(result))
            return result;

          //
          // Map the global point into this scrolledView's coordinate space.
          //

          result = GetViewAncestorOffset(scrolledView, nsnull, &globalOffset.x, &globalOffset.y);

          if (NS_FAILED(result))
            return result;

          nsPoint newPoint = globalPoint - globalOffset;

          //
          // Scroll the point into the visible rect of the scrolled view.
          //

          PRBool parentDidScroll = PR_FALSE;

          result = ScrollPointIntoClipView(aPresContext, scrolledView, newPoint, &parentDidScroll);

          if (NS_FAILED(result))
            return result;

          *aDidScroll = *aDidScroll || parentDidScroll;

          //
          // Now get the parent of this scrollable view so we
          // can scroll the next parent view.
          //

          view = 0;
          result = CallQueryInterface(scrollableView, &view);
          if (!view)
            return result;

          view = view->GetParent();
        }
      }
    }
  }

  return NS_OK;
}

nsresult
nsTypedSelection::DoAutoScrollView(nsIPresContext *aPresContext, nsIView *aView, nsPoint& aPoint, PRBool aScrollParentViews)
{
  if (!aPresContext || !aView)
    return NS_ERROR_NULL_POINTER;

  nsresult result;

  if (mAutoScrollTimer)
    result = mAutoScrollTimer->Stop();

  //
  // Calculate the global offset of the view.
  //

  nsPoint globalOffset;

  result = GetViewAncestorOffset(aView, nsnull, &globalOffset.x, &globalOffset.y);

  if (NS_FAILED(result))
    return result;

  //
  // Convert aPoint into global coordinates so we can get back
  // to the same point after all the parent views have scrolled.
  //

  nsPoint globalPoint = aPoint + globalOffset;

  //
  // Now scroll aPoint into view.
  //

  PRBool didScroll = PR_FALSE;

  result = ScrollPointIntoView(aPresContext, aView, aPoint, aScrollParentViews, &didScroll);

  if (NS_FAILED(result))
    return result;

  //
  // Start the AutoScroll timer if neccessary.
  //

  if (didScroll && mAutoScrollTimer)
  {
    //
    // Map the globalPoint back into aView's coordinate system. We
    // have to get the globalOffsets again because aView's
    // window and it's parents may have changed their offsets.
    //
    result = GetViewAncestorOffset(aView, nsnull, &globalOffset.x, &globalOffset.y);

    if (NS_FAILED(result))
      return result;

    nsPoint svPoint = globalPoint - globalOffset;

    result = mAutoScrollTimer->Start(aPresContext, aView, svPoint);
  }

  return NS_OK;
}

nsresult
nsTypedSelection::DoAutoScroll(nsIPresContext *aPresContext, nsIFrame *aFrame, nsPoint& aPoint)
{
  if (!aPresContext || !aFrame)
    return NS_ERROR_NULL_POINTER;

  // Find the closest view to the frame!

  nsIView *closestView = aFrame->GetClosestView();
  if (!closestView)
    return NS_ERROR_FAILURE;

  return DoAutoScrollView(aPresContext, closestView, aPoint, PR_TRUE);
}

NS_IMETHODIMP
nsTypedSelection::GetEnumerator(nsIEnumerator **aIterator)
{
  nsresult status = NS_ERROR_OUT_OF_MEMORY;
  nsSelectionIterator *iterator =  new nsSelectionIterator(this);
  if ( iterator && NS_FAILED(status = CallQueryInterface(iterator, aIterator)) )
    delete iterator;
  return status;
}



/** RemoveAllRanges zeroes the selection
 */
NS_IMETHODIMP
nsTypedSelection::RemoveAllRanges()
{
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  nsCOMPtr<nsIPresContext>  presContext;
  GetPresContext(getter_AddRefs(presContext));


  nsresult  result = Clear(presContext);
  if (NS_FAILED(result))
    return result;
  
  // Turn off signal for table selection
  mFrameSelection->ClearTableCellSelection();

  return mFrameSelection->NotifySelectionListeners(GetType());
  // Also need to notify the frames!
  // PresShell::ContentChanged should do that on DocumentChanged
}

/** AddRange adds the specified range to the selection
 *  @param aRange is the range to be added
 */
NS_IMETHODIMP
nsTypedSelection::AddRange(nsIDOMRange* aRange)
{
  if (!aRange) return NS_ERROR_NULL_POINTER;

  // This inserts a table cell range in proper document order
  //  and returns NS_ERROR_FAILURE if range doesn't contain just one table cell
  PRBool didAddRange;
  nsresult result = addTableCellRange(aRange, &didAddRange);
  if (NS_FAILED(result)) return result;

  if (!didAddRange)
  {
    result = AddItem(aRange);
    if (NS_FAILED(result)) return result;
  }

  PRInt32 count;
  result = GetRangeCount(&count);
  if (NS_FAILED(result)) return result;

  if (count <= 0)
  {
    NS_ASSERTION(0,"bad count after additem\n");
    return NS_ERROR_FAILURE;
  }
  setAnchorFocusRange(count -1);
  
  nsCOMPtr<nsIPresContext>  presContext;
  GetPresContext(getter_AddRefs(presContext));
  selectFrames(presContext, aRange, PR_TRUE);        

  //ScrollIntoView(); this should not happen automatically
  if (!mFrameSelection)
    return NS_OK;//nothing to do

  return mFrameSelection->NotifySelectionListeners(GetType());
}

NS_IMETHODIMP
nsTypedSelection::RemoveRange(nsIDOMRange* aRange)
{
  if (!aRange)
    return NS_ERROR_INVALID_ARG;
  RemoveItem(aRange);
  
  nsCOMPtr<nsIPresContext>  presContext;
  GetPresContext(getter_AddRefs(presContext));
  selectFrames(presContext, aRange, PR_FALSE);        
  if (aRange == mAnchorFocusRange.get())
  {
    PRInt32 cnt = mRangeArray.Count();
    if (cnt > 0)
    {
      setAnchorFocusRange(cnt - 1);//reset anchor to LAST range.
      ScrollIntoView();
    }
  }
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  return mFrameSelection->NotifySelectionListeners(GetType());
}



/*
 * Collapse sets the whole selection to be one point.
 */
NS_IMETHODIMP
nsTypedSelection::Collapse(nsIDOMNode* aParentNode, PRInt32 aOffset)
{
  if (!aParentNode)
    return NS_ERROR_INVALID_ARG;
  mFrameSelection->InvalidateDesiredX();
  if (!IsValidSelectionPoint(mFrameSelection, aParentNode))
    return NS_ERROR_FAILURE;
  nsresult result;
  // Delete all of the current ranges
  if (NS_FAILED(SetOriginalAnchorPoint(aParentNode,aOffset)))
    return NS_ERROR_FAILURE; //???
  nsCOMPtr<nsIPresContext>  presContext;
  GetPresContext(getter_AddRefs(presContext));
  Clear(presContext);

  // Turn off signal for table selection
  if (mFrameSelection)
    mFrameSelection->ClearTableCellSelection();

  nsCOMPtr<nsIDOMRange> range;
  NS_NewRange(getter_AddRefs(range));
  if (! range){
    NS_ASSERTION(PR_FALSE,"Couldn't make a range - nsSelection::Collapse");
    return NS_ERROR_UNEXPECTED;
  }
  result = range->SetEnd(aParentNode, aOffset);
  if (NS_FAILED(result))
    return result;
  result = range->SetStart(aParentNode, aOffset);
  if (NS_FAILED(result))
    return result;

#ifdef DEBUG_SELECTION
  if (aParentNode)
  {
    nsCOMPtr<nsIContent>content;
    content = do_QueryInterface(aParentNode);
    if (!content)
      return NS_ERROR_FAILURE;

    const char *tagString;
    content->Tag()->GetUTF8String(&tagString);
    printf ("Sel. Collapse to %p %s %d\n", content, tagString, aOffset);
  }
  else {
    printf ("Sel. Collapse set to null parent.\n");
  }
#endif


  result = AddItem(range);
  setAnchorFocusRange(0);
  selectFrames(presContext, range,PR_TRUE);
  if (NS_FAILED(result))
    return result;
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  return mFrameSelection->NotifySelectionListeners(GetType());
}

/*
 * Sets the whole selection to be one point
 * at the start of the current selection
 */
NS_IMETHODIMP
nsTypedSelection::CollapseToStart()
{
  PRInt32 cnt;
  nsresult rv = GetRangeCount(&cnt);
  if (NS_FAILED(rv) || cnt <= 0)
    return NS_ERROR_FAILURE;

  // Get the first range
  nsIDOMRange* firstRange = mRangeArray[0];
  if (!firstRange)
    return NS_ERROR_FAILURE;

  nsCOMPtr<nsIDOMNode> parent;
  rv = firstRange->GetStartContainer(getter_AddRefs(parent));
  if (NS_SUCCEEDED(rv))
  {
    if (parent)
    {
      PRInt32 startOffset;
      firstRange->GetStartOffset(&startOffset);
      rv = Collapse(parent, startOffset);
    } else {
      // not very likely!
      rv = NS_ERROR_FAILURE;
    }
  }
  return rv;
}

/*
 * Sets the whole selection to be one point
 * at the end of the current selection
 */
NS_IMETHODIMP
nsTypedSelection::CollapseToEnd()
{
  PRInt32 cnt;
  nsresult rv = GetRangeCount(&cnt);
  if (NS_FAILED(rv) || cnt <= 0)
    return NS_ERROR_FAILURE;

  // Get the last range
  nsIDOMRange* lastRange = mRangeArray[cnt-1];
  if (!lastRange)
    return NS_ERROR_FAILURE;

  nsCOMPtr<nsIDOMNode> parent;
  rv = lastRange->GetEndContainer(getter_AddRefs(parent));
  if (NS_SUCCEEDED(rv))
  {
    if (parent)
    {
      PRInt32 endOffset;
      lastRange->GetEndOffset(&endOffset);
      rv = Collapse(parent, endOffset);
    } else {
      // not very likely!
      rv = NS_ERROR_FAILURE;
    }
  }
  return rv;
}

/*
 * IsCollapsed -- is the whole selection just one point, or unset?
 */
NS_IMETHODIMP
nsTypedSelection::GetIsCollapsed(PRBool* aIsCollapsed)
{
  if (!aIsCollapsed)
    return NS_ERROR_NULL_POINTER;

  PRInt32 cnt = mRangeArray.Count();;
  if (cnt == 0)
  {
    *aIsCollapsed = PR_TRUE;
    return NS_OK;
  }
  
  if (cnt != 1)
  {
    *aIsCollapsed = PR_FALSE;
    return NS_OK;
  }
  
  return mRangeArray[0]->GetCollapsed(aIsCollapsed);
}

NS_IMETHODIMP
nsTypedSelection::GetRangeCount(PRInt32* aRangeCount)
{
  if (!aRangeCount) 
    return NS_ERROR_NULL_POINTER;

  *aRangeCount = mRangeArray.Count();

  return NS_OK;
}

NS_IMETHODIMP
nsTypedSelection::GetRangeAt(PRInt32 aIndex, nsIDOMRange** aReturn)
{
  if (!aReturn)
    return NS_ERROR_NULL_POINTER;

  PRInt32 cnt = mRangeArray.Count();
  if (aIndex < 0 || aIndex >= cnt)
    return NS_ERROR_INVALID_ARG;

  *aReturn = mRangeArray[aIndex];
  NS_IF_ADDREF(*aReturn);

  return NS_OK;
}

#ifdef OLD_SELECTION

//may change parameters may not.
//return NS_ERROR_FAILURE if invalid new selection between anchor and passed in parameters
NS_IMETHODIMP
nsTypedSelection::FixupSelectionPoints(nsIDOMRange *aRange , nsDirection *aDir, PRBool *aFixupState)
{
  if (!aRange || !aFixupState)
    return NS_ERROR_NULL_POINTER;
  *aFixupState = PR_FALSE;
  nsresult res;

  //startNode is the beginning or "anchor" of the range
  //end Node is the end or "focus of the range
  nsCOMPtr<nsIDOMNode> startNode;
  nsCOMPtr<nsIDOMNode> endNode;
  PRInt32 startOffset;
  PRInt32 endOffset;
  nsresult result;
  if (*aDir == eDirNext)
  {
    if (NS_FAILED(GetOriginalAnchorPoint(getter_AddRefs(startNode), &startOffset)))
    {
      aRange->GetStartParent(getter_AddRefs(startNode));
      aRange->GetStartOffset(&startOffset);
    }
    aRange->GetEndParent(getter_AddRefs(endNode));
    aRange->GetEndOffset(&endOffset);
  }
  else
  {
    if (NS_FAILED(GetOriginalAnchorPoint(getter_AddRefs(startNode), &startOffset)))
    {
      aRange->GetEndParent(getter_AddRefs(startNode));
      aRange->GetEndOffset(&startOffset);
    }
    aRange->GetStartParent(getter_AddRefs(endNode));
    aRange->GetStartOffset(&endOffset);
  }
  if (!startNode || !endNode)
    return NS_ERROR_FAILURE;

  // if end node is a tbody then all bets are off we cannot select "rows"
  nsIAtom *atom = GetTag(endNode);
  if (atom == nsHTMLAtoms::tbody)
    return NS_ERROR_FAILURE; //cannot select INTO row node ony cells

  //get common parent
  nsCOMPtr<nsIDOMNode> parent;
  nsCOMPtr<nsIDOMRange> subRange;
  NS_NewRange(getter_AddRefs(subRange));
  if (!subRange) return NS_ERROR_OUT_OF_MEMORY

  result = subRange->SetStart(startNode,startOffset);
  if (NS_FAILED(result))
    return result;
  result = subRange->SetEnd(endNode,endOffset);
  if (NS_FAILED(result))
  {
    result = subRange->SetEnd(startNode,startOffset);
    if (NS_FAILED(result))
      return result;
    result = subRange->SetStart(endNode,endOffset);
    if (NS_FAILED(result))
      return result;
  }

  res = subRange->GetCommonParent(getter_AddRefs(parent));
  if (NS_FAILED(res) || !parent)
    return res;
 
  //look for dest. if you see a cell you are in "cell mode"
  //if you see a table you select "whole" table

  //src first 
  nsCOMPtr<nsIDOMNode> tempNode;
  nsCOMPtr<nsIDOMNode> tempNode2;
  PRBool cellMode = PR_FALSE;
  PRBool dirtystart = PR_FALSE;
  PRBool dirtyend = PR_FALSE;
  if (startNode != endNode)
  {
    if (parent != startNode)
    {
      result = startNode->GetParentNode(getter_AddRefs(tempNode));
      if (NS_FAILED(result) || !tempNode)
        return NS_ERROR_FAILURE;
      while (tempNode != parent)
      {
        atom = GetTag(tempNode);
        if (atom == nsHTMLAtoms::table) //select whole table  if in cell mode, wait for cell
        {
          result = ParentOffset(tempNode, getter_AddRefs(startNode), &startOffset);
          if (NS_FAILED(result))
            return NS_ERROR_FAILURE;
          if (*aDir == eDirPrevious) //select after
            startOffset++;
          dirtystart = PR_TRUE;
          cellMode = PR_FALSE;
        }
        else if (atom == nsHTMLAtoms::td) //you are in "cell" mode put selection to end of cell
        {
          cellMode = PR_TRUE;
          result = ParentOffset(tempNode, getter_AddRefs(startNode), &startOffset);
          if (NS_FAILED(result))
            return result;
          if (*aDir == eDirPrevious) //select after
            startOffset++;
          dirtystart = PR_TRUE;
        }
        result = tempNode->GetParentNode(getter_AddRefs(tempNode2));
        if (NS_FAILED(result) || !tempNode2)
          return NS_ERROR_FAILURE;
        tempNode = tempNode2;
      }
    }
  
  //now for dest node
    if (parent != endNode)
    {
      result = endNode->GetParentNode(getter_AddRefs(tempNode));
      PRBool found = !cellMode;
      if (NS_FAILED(result) || !tempNode)
        return NS_ERROR_FAILURE;
      while (tempNode != parent)
      {
        atom = GetTag(tempNode);
        if (atom == nsHTMLAtoms::table) //select whole table  if in cell mode, wait for cell
        {
          if (!cellMode)
          {
            result = ParentOffset(tempNode, getter_AddRefs(endNode), &endOffset);
            if (NS_FAILED(result))
              return result;
            if (*aDir == eDirNext) //select after
              endOffset++;
            dirtyend = PR_TRUE;
          }
          else
            found = PR_FALSE; //didnt find the right cell yet
        }
        else if (atom == nsHTMLAtoms::td) //you are in "cell" mode put selection to end of cell
        {
          result = ParentOffset(tempNode, getter_AddRefs(endNode), &endOffset);
          if (NS_FAILED(result))
            return result;
          if (*aDir == eDirNext) //select after
            endOffset++;
          found = PR_TRUE;
          dirtyend = PR_TRUE;
        }
        result = tempNode->GetParentNode(getter_AddRefs(tempNode2));
        if (NS_FAILED(result) || !tempNode2)
          return NS_ERROR_FAILURE;
        tempNode = tempNode2;
      }
      if (!found)
        return NS_ERROR_FAILURE;
    }
  }
  if (*aDir == eDirNext)
  {
    if (FetchAnchorNode() == startNode.get() && FetchFocusNode() == endNode.get() &&
      FetchAnchorOffset() == startOffset && FetchFocusOffset() == endOffset)
    {
      *aFixupState = PR_FALSE;
      return NS_ERROR_FAILURE;//nothing to do
    }
  }
  else
  {
    if (FetchAnchorNode() == endNode.get() && FetchFocusNode() == startNode.get() &&
      FetchAnchorOffset() == endOffset && FetchFocusOffset() == startOffset)
    {
      *aFixupState = PR_FALSE;
      return NS_ERROR_FAILURE;//nothing to do
    }
  }
  if (mFixupState && !dirtyend && !dirtystart)//no mor fixup! all bets off
  {
    dirtystart = PR_TRUE;//force a reset of anchor positions
    dirtystart = PR_TRUE;
    *aFixupState = PR_TRUE;//redraw all selection here
    mFixupState = PR_FALSE;//no more fixup for next time
  }
  else
  if ((dirtystart || dirtyend) && *aDir != mDirection) //fixup took place but new direction all bets are off
  {
    *aFixupState = PR_TRUE;
    //mFixupState = PR_FALSE;
  }
  else
  if (dirtystart && (FetchAnchorNode() != startNode.get() || FetchAnchorOffset() != startOffset))
  {
    *aFixupState = PR_TRUE;
    mFixupState  = PR_TRUE;
  }
  else
  if (dirtyend && (FetchFocusNode() != endNode.get() || FetchFocusOffset() != endOffset))
  {
    *aFixupState = PR_TRUE;
    mFixupState  = PR_TRUE;
  }
  else
  {
    mFixupState = dirtystart || dirtyend;
    *aFixupState = PR_FALSE;
  }
  if (dirtystart || dirtyend){
    if (*aDir == eDirNext)
    {
      if (NS_FAILED(aRange->SetStart(startNode,startOffset)) || NS_FAILED(aRange->SetEnd(endNode, endOffset)))
      {
        *aDir = eDirPrevious;
        aRange->SetStart(endNode, endOffset);
        aRange->SetEnd(startNode, startOffset);
      }
    }
    else
    {
      if (NS_FAILED(aRange->SetStart(endNode,endOffset)) || NS_FAILED(aRange->SetEnd(startNode, startOffset)))
      {
        *aDir = eDirNext;
        aRange->SetStart(startNode, startOffset);
        aRange->SetEnd(endNode, endOffset);
      }
    }
  }
  return NS_OK;
}
#endif //OLD_SELECTION




NS_IMETHODIMP
nsTypedSelection::SetOriginalAnchorPoint(nsIDOMNode *aNode, PRInt32 aOffset)
{
  if (!aNode){
    mOriginalAnchorRange = 0;
    return NS_OK;
  }
  nsCOMPtr<nsIDOMRange> newRange;
  nsresult result;
  NS_NewRange(getter_AddRefs(newRange));
  if (!newRange) return NS_ERROR_OUT_OF_MEMORY;

  result = newRange->SetStart(aNode,aOffset);
  if (NS_FAILED(result))
    return result;
  result = newRange->SetEnd(aNode,aOffset);
  if (NS_FAILED(result))
    return result;

  mOriginalAnchorRange = newRange;
  return result;
}



NS_IMETHODIMP
nsTypedSelection::GetOriginalAnchorPoint(nsIDOMNode **aNode, PRInt32 *aOffset)
{
  if (!aNode || !aOffset || !mOriginalAnchorRange)
    return NS_ERROR_NULL_POINTER;
  nsresult result;
  result = mOriginalAnchorRange->GetStartContainer(aNode);
  if (NS_FAILED(result))
    return result;
  result = mOriginalAnchorRange->GetStartOffset(aOffset);
  return result;
}


/*
utility function
*/
NS_IMETHODIMP
nsTypedSelection::CopyRangeToAnchorFocus(nsIDOMRange *aRange)
{
  nsCOMPtr<nsIDOMNode> startNode;
  nsCOMPtr<nsIDOMNode> endNode;
  PRInt32 startOffset;
  PRInt32 endOffset;
  aRange->GetStartContainer(getter_AddRefs(startNode));
  aRange->GetEndContainer(getter_AddRefs(endNode));
  aRange->GetStartOffset(&startOffset);
  aRange->GetEndOffset(&endOffset);
  if (NS_FAILED(mAnchorFocusRange->SetStart(startNode,startOffset)))
  {
    if (NS_FAILED(mAnchorFocusRange->SetEnd(endNode,endOffset)))
      return NS_ERROR_FAILURE;//???
    if (NS_FAILED(mAnchorFocusRange->SetStart(startNode,startOffset)))
      return NS_ERROR_FAILURE;//???
  }
  else if (NS_FAILED(mAnchorFocusRange->SetEnd(endNode,endOffset)))
          return NS_ERROR_FAILURE;//???
  return NS_OK;
}

/*
Notes which might come in handy for extend:

We can tell the direction of the selection by asking for the anchors selection
if the begin is less than the end then we know the selection is to the "right".
else it is a backwards selection.
a = anchor
1 = old cursor
2 = new cursor

  if (a <= 1 && 1 <=2)    a,1,2  or (a1,2)
  if (a < 2 && 1 > 2)     a,2,1
  if (1 < a && a <2)      1,a,2
  if (a > 2 && 2 >1)      1,2,a
  if (2 < a && a <1)      2,a,1
  if (a > 1 && 1 >2)      2,1,a
then execute
a  1  2 select from 1 to 2
a  2  1 deselect from 2 to 1
1  a  2 deselect from 1 to a select from a to 2
1  2  a deselect from 1 to 2
2  1  a = continue selection from 2 to 1
*/


/*
 * Extend extends the selection away from the anchor.
 * We don't need to know the direction, because we always change the focus.
 */
NS_IMETHODIMP
nsTypedSelection::Extend(nsIDOMNode* aParentNode, PRInt32 aOffset)
{
  if (!aParentNode)
    return NS_ERROR_INVALID_ARG;

  // First, find the range containing the old focus point:
  if (!mAnchorFocusRange)
    return NS_ERROR_NOT_INITIALIZED;

  nsresult res;
  if (!IsValidSelectionPoint(mFrameSelection, aParentNode))
    return NS_ERROR_FAILURE;

  //mFrameSelection->InvalidateDesiredX();
  nsCOMPtr<nsIDOMRange> difRange;
  NS_NewRange(getter_AddRefs(difRange));
  nsCOMPtr<nsIDOMRange> range;

  if (FetchFocusNode() ==  aParentNode && FetchFocusOffset() == aOffset)
    return NS_ERROR_FAILURE;//same node nothing to do!

  res = mAnchorFocusRange->CloneRange(getter_AddRefs(range));
  //range = mAnchorFocusRange;

  nsCOMPtr<nsIDOMNode> startNode;
  nsCOMPtr<nsIDOMNode> endNode;
  PRInt32 startOffset;
  PRInt32 endOffset;

  range->GetStartContainer(getter_AddRefs(startNode));
  range->GetEndContainer(getter_AddRefs(endNode));
  range->GetStartOffset(&startOffset);
  range->GetEndOffset(&endOffset);


  nsDirection dir = GetDirection();
  PRBool fixupState = PR_FALSE; //if there was a previous fixup the optimal drawing erasing will NOT work
  if (NS_FAILED(res))
    return res;

  NS_NewRange(getter_AddRefs(difRange));
  //compare anchor to old cursor.

  if (NS_FAILED(res))
    return res;
  PRInt32 result1 = ComparePoints(FetchAnchorNode(), FetchAnchorOffset() 
                                  ,FetchFocusNode(), FetchFocusOffset());
  //compare old cursor to new cursor
  PRInt32 result2 = ComparePoints(FetchFocusNode(), FetchFocusOffset(),
                            aParentNode, aOffset );
  //compare anchor to new cursor
  PRInt32 result3 = ComparePoints(FetchAnchorNode(), FetchAnchorOffset(),
                            aParentNode , aOffset );

  if (result2 == 0) //not selecting anywhere
    return NS_OK;

  nsCOMPtr<nsIPresContext>  presContext;
  GetPresContext(getter_AddRefs(presContext));
  if ((result1 == 0 && result3 < 0) || (result1 <= 0 && result2 < 0)){//a1,2  a,1,2
    //select from 1 to 2 unless they are collapsed
    res = range->SetEnd(aParentNode,aOffset);
    if (NS_FAILED(res))
      return res;
    dir = eDirNext;
    res = difRange->SetEnd(FetchEndParent(range), FetchEndOffset(range));
    res |= difRange->SetStart(FetchFocusNode(), FetchFocusOffset());
    if (NS_FAILED(res))
      return res;
#ifdef OLD_SELECTION
    res = FixupSelectionPoints(range, &dir, &fixupState);
#endif
    if (NS_FAILED(res))
      return res;
    if (fixupState) 
    {
#ifdef OLD_SELECTION
      selectFrames(mAnchorFocusRange, PR_FALSE);
      selectFrames(range, PR_TRUE);
#endif
    }
    else{
      selectFrames(presContext, difRange , PR_TRUE);
    }
    res = CopyRangeToAnchorFocus(range);
    if (NS_FAILED(res))
      return res;
  }
  else if (result1 == 0 && result3 > 0){//2, a1
    //select from 2 to 1a
    dir = eDirPrevious;
    res = range->SetStart(aParentNode,aOffset);
    if (NS_FAILED(res))
      return res;
#ifdef OLD_SELECTION
    res = FixupSelectionPoints(range, &dir, &fixupState);
    if (NS_FAILED(res))
      return res;
    if (fixupState) //unselect previous and select new state has changed to not fixed up
    {
      selectFrames(mAnchorFocusRange, PR_FALSE);
      selectFrames(range, PR_TRUE);
    }
    else
#endif
      selectFrames(presContext, range, PR_TRUE);
    res = CopyRangeToAnchorFocus(range);
    if (NS_FAILED(res))
      return res;
  }
  else if (result3 <= 0 && result2 >= 0) {//a,2,1 or a2,1 or a,21 or a21
    //deselect from 2 to 1
    res = difRange->SetEnd(FetchFocusNode(), FetchFocusOffset());
    res |= difRange->SetStart(aParentNode, aOffset);
    if (NS_FAILED(res))
      return res;

    res = range->SetEnd(aParentNode,aOffset);
    if (NS_FAILED(res))
      return res;
#ifdef OLD_SELECTION    
    dir = eDirNext;
    res = FixupSelectionPoints(range, &dir, &fixupState);
#endif
    if (NS_FAILED(res))
      return res;
    if (fixupState) //unselect previous and select new state has changed to not fixed up
    {
#ifdef OLD_SELECTION    
      selectFrames(mAnchorFocusRange, PR_FALSE);
      selectFrames(range, PR_TRUE);
#endif
    }
    else 
    {
      res = CopyRangeToAnchorFocus(range);
      if (NS_FAILED(res))
        return res;
      RemoveItem(mAnchorFocusRange);
      selectFrames(presContext, difRange, PR_FALSE);//deselect now if fixup succeeded
      AddItem(mAnchorFocusRange);
      difRange->SetEnd(FetchEndParent(range),FetchEndOffset(range));
      selectFrames(presContext, difRange, PR_TRUE);//must reselect last node maybe more if fixup did something
    }
  }
  else if (result1 >= 0 && result3 <= 0) {//1,a,2 or 1a,2 or 1,a2 or 1a2
    if (GetDirection() == eDirPrevious){
      res = range->SetStart(endNode,endOffset);
      if (NS_FAILED(res))
        return res;
    }
    dir = eDirNext;
    res = range->SetEnd(aParentNode,aOffset);
    if (NS_FAILED(res))
      return res;
#ifdef OLD_SELECTION
    res = FixupSelectionPoints(range, &dir, &fixupState);
    if (NS_FAILED(res))
      return res;

    if (fixupState) //unselect previous and select new state has changed to not fixed up
    {
      selectFrames(mAnchorFocusRange, PR_FALSE);
      selectFrames(range, PR_TRUE);
    }
    else 
#endif
    {
      if (FetchFocusNode() != FetchAnchorNode() || FetchFocusOffset() != FetchAnchorOffset() ){//if collapsed diff dont do anything
        res = difRange->SetStart(FetchFocusNode(), FetchFocusOffset());
        res |= difRange->SetEnd(FetchAnchorNode(), FetchAnchorOffset());
        if (NS_FAILED(res))
          return res;
        res = CopyRangeToAnchorFocus(range);
        if (NS_FAILED(res))
          return res;
        //deselect from 1 to a
        RemoveItem(mAnchorFocusRange);
        selectFrames(presContext, difRange , PR_FALSE);
        AddItem(mAnchorFocusRange);
      }
      else
      {
        res = CopyRangeToAnchorFocus(range);
        if (NS_FAILED(res))
          return res;
      }
      //select from a to 2
      selectFrames(presContext, range , PR_TRUE);
    }
  }
  else if (result2 <= 0 && result3 >= 0) {//1,2,a or 12,a or 1,2a or 12a
    //deselect from 1 to 2
    res = difRange->SetEnd(aParentNode, aOffset);
    res |= difRange->SetStart(FetchFocusNode(), FetchFocusOffset());
    if (NS_FAILED(res))
      return res;
    dir = eDirPrevious;
    res = range->SetStart(aParentNode,aOffset);
    if (NS_FAILED(res))
      return res;

#ifdef OLD_SELECTION
    res = FixupSelectionPoints(range, &dir, &fixupState);
#endif
    if (NS_FAILED(res))
      return res;
    if (fixupState) //unselect previous and select new state has changed to not fixed up
    {
#ifdef OLD_SELECTION
      selectFrames(mAnchorFocusRange, PR_FALSE);
      selectFrames(range, PR_TRUE);
#endif
    }
    else 
    {
      res = CopyRangeToAnchorFocus(range);
      if (NS_FAILED(res))
        return res;
      RemoveItem(mAnchorFocusRange);
      selectFrames(presContext, difRange , PR_FALSE);
      AddItem(mAnchorFocusRange);
      difRange->SetStart(FetchStartParent(range),FetchStartOffset(range));
      selectFrames(presContext, difRange, PR_TRUE);//must reselect last node
    }
  }
  else if (result3 >= 0 && result1 <= 0) {//2,a,1 or 2a,1 or 2,a1 or 2a1
    if (GetDirection() == eDirNext){
      range->SetEnd(startNode,startOffset);
    }
    dir = eDirPrevious;
    res = range->SetStart(aParentNode,aOffset);
    if (NS_FAILED(res))
      return res;
#ifdef OLD_SELECTION
    res = FixupSelectionPoints(range, &dir, &fixupState);
    if (NS_FAILED(res))
      return res;
    if (fixupState) //unselect previous and select new state has changed to not fixed up
    {
      selectFrames(mAnchorFocusRange, PR_FALSE);
      selectFrames(range, PR_TRUE);
    }
    else
#endif
    {
      //deselect from a to 1
      if (FetchFocusNode() != FetchAnchorNode() || FetchFocusOffset() != FetchAnchorOffset() ){//if collapsed diff dont do anything
        res = difRange->SetStart(FetchAnchorNode(), FetchAnchorOffset());
        res |= difRange->SetEnd(FetchFocusNode(), FetchFocusOffset());
        res = CopyRangeToAnchorFocus(range);
        if (NS_FAILED(res))
          return res;
        RemoveItem(mAnchorFocusRange);
        selectFrames(presContext, difRange, 0);
        AddItem(mAnchorFocusRange);
      }
      else
      {
        res = CopyRangeToAnchorFocus(range);
        if (NS_FAILED(res))
          return res;
      }
      //select from 2 to a
      selectFrames(presContext, range , PR_TRUE);
    }
  }
  else if (result2 >= 0 && result1 >= 0) {//2,1,a or 21,a or 2,1a or 21a
    //select from 2 to 1
    res = range->SetStart(aParentNode,aOffset);
    if (NS_FAILED(res))
      return res;
    dir = eDirPrevious;
    res = difRange->SetEnd(FetchFocusNode(), FetchFocusOffset());
    res |= difRange->SetStart(FetchStartParent(range), FetchStartOffset(range));
    if (NS_FAILED(res))
      return res;

#ifdef OLD_SELECTION
    res = FixupSelectionPoints(range, &dir, &fixupState);
#endif
    if (NS_FAILED(res))
      return res;
    if (fixupState) //unselect previous and select new state has changed to not fixed up
    {
#ifdef OLD_SELECTION
      selectFrames(mAnchorFocusRange, PR_FALSE);
      selectFrames(range, PR_TRUE);
#endif
    }
    else {
      selectFrames(presContext, difRange, PR_TRUE);
    }
    res = CopyRangeToAnchorFocus(range);
    if (NS_FAILED(res))
      return res;
  }

  DEBUG_OUT_RANGE(range);
#if 0
  if (eDirNext == mDirection)
    printf("    direction = 1  LEFT TO RIGHT\n");
  else
    printf("    direction = 0  RIGHT TO LEFT\n");
#endif
  SetDirection(dir);
#ifdef DEBUG_SELECTION
  if (aParentNode)
  {
    nsCOMPtr<nsIContent>content;
    content = do_QueryInterface(aParentNode);

    const char *tagString;
    content->Tag()->GetUTF8String(&tagString);
    printf ("Sel. Extend to %p %s %d\n", content, tagString, aOffset);
  }
  else {
    printf ("Sel. Extend set to null parent.\n");
  }
#endif
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  return mFrameSelection->NotifySelectionListeners(GetType());
}

static nsresult
GetChildOffset(nsIDOMNode *aChild, nsIDOMNode *aParent, PRInt32 &aOffset)
{
  NS_ASSERTION((aChild && aParent), "bad args");
  nsCOMPtr<nsIContent> content = do_QueryInterface(aParent);
  nsCOMPtr<nsIContent> cChild = do_QueryInterface(aChild);

  if (!cChild || !content)
    return NS_ERROR_NULL_POINTER;

  aOffset = content->IndexOf(cChild);

  return NS_OK;
}

NS_IMETHODIMP
nsTypedSelection::SelectAllChildren(nsIDOMNode* aParentNode)
{
  NS_ENSURE_ARG_POINTER(aParentNode);
  
  if (mFrameSelection) 
  {
    mFrameSelection->PostReason(nsISelectionListener::SELECTALL_REASON);
  }
  nsresult result = Collapse(aParentNode, 0);
  if (NS_SUCCEEDED(result))
  {
    nsCOMPtr<nsIDOMNode>lastChild;
    result = aParentNode->GetLastChild(getter_AddRefs(lastChild));
    if ((NS_SUCCEEDED(result)) && lastChild)
    {
      PRInt32 numBodyChildren=0;
      GetChildOffset(lastChild, aParentNode, numBodyChildren);
      if (mFrameSelection) 
      {
        mFrameSelection->PostReason(nsISelectionListener::SELECTALL_REASON);
      }
      result = Extend(aParentNode, numBodyChildren+1);
    }
  }
  return result;
}

NS_IMETHODIMP
nsTypedSelection::ContainsNode(nsIDOMNode* aNode, PRBool aRecursive, PRBool* aYes)
{
  if (!aYes)
    return NS_ERROR_NULL_POINTER;
  *aYes = PR_FALSE;

  // Iterate over the ranges in the selection checking for the content:
  PRInt32 cnt = mRangeArray.Count();
  for (PRInt32 i = 0; i < cnt; ++i)
  {
    nsIDOMRange* range = mRangeArray[i];
    if (!range)
      return NS_ERROR_UNEXPECTED;

    nsCOMPtr<nsIContent> content (do_QueryInterface(aNode));
    if (content)
    {
      if (IsNodeIntersectsRange(content, range))
      {
        // If recursive, then we're done -- IsNodeIntersectsRange does the right thing
        if (aRecursive)
        {
          *aYes = PR_TRUE;
          return NS_OK;
        }

        // else not recursive -- node itself must be contained,
        // so we need to do more checking
        PRBool nodeStartsBeforeRange, nodeEndsAfterRange;
        if (NS_SUCCEEDED(nsRange::CompareNodeToRange(content, range,
                                                     &nodeStartsBeforeRange,
                                                     &nodeEndsAfterRange)))
        {
#ifdef DEBUG_ContainsNode
          nsAutoString name, value;
          aNode->GetNodeName(name);
          aNode->GetNodeValue(value);
          printf("%s [%s]: %d, %d\n", NS_LossyConvertUCS2toASCII(name).get(),
                 NS_LossyConvertUCS2toASCII(value).get(),
                 nodeStartsBeforeRange, nodeEndsAfterRange);
#endif
          PRUint16 nodeType;
          aNode->GetNodeType(&nodeType);
          if ((!nodeStartsBeforeRange && !nodeEndsAfterRange)
              || (nodeType == nsIDOMNode::TEXT_NODE))
          {
            *aYes = PR_TRUE;
            return NS_OK;
          }
        }
      }
    }
  }
  return NS_OK;
}


nsresult
nsTypedSelection::GetPresContext(nsIPresContext **aPresContext)
{
  if (!mFrameSelection)
    return NS_ERROR_FAILURE;//nothing to do
  nsIFocusTracker *tracker = mFrameSelection->GetTracker();

  if (!tracker)
    return NS_ERROR_NULL_POINTER;

  return tracker->GetPresContext(aPresContext);
}

nsresult
nsTypedSelection::GetPresShell(nsIPresShell **aPresShell)
{
  if (mPresShellWeak)
  {
    nsCOMPtr<nsIPresShell> presShell = do_QueryReferent(mPresShellWeak);
    if (presShell)
      NS_ADDREF(*aPresShell = presShell);
    return NS_OK;
  }
  nsresult rv = NS_OK;
  if (!mFrameSelection)
    return NS_ERROR_FAILURE;//nothing to do

  nsIFocusTracker *tracker = mFrameSelection->GetTracker();

  if (!tracker)
    return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsIPresContext> presContext;

  rv = tracker->GetPresContext(getter_AddRefs(presContext));

  if (NS_FAILED(rv))
    return rv;

  if (!presContext)
    return NS_ERROR_NULL_POINTER;
  
  nsIPresShell *shell = presContext->GetPresShell();
  mPresShellWeak = do_GetWeakReference(shell);    // the presshell owns us, so no addref
  if (mPresShellWeak)
    NS_ADDREF(*aPresShell = shell);
  return rv;
}

nsresult
nsTypedSelection::GetRootScrollableView(nsIScrollableView **aScrollableView)
{
  //
  // NOTE: This method returns a NON-AddRef'd pointer
  //       to the scrollable view!
  //
  NS_ENSURE_ARG_POINTER(aScrollableView);

  if (!mFrameSelection)
    return NS_ERROR_FAILURE;//nothing to do
  nsresult rv;
  nsIScrollableView *scrollView;
  rv = mFrameSelection->GetScrollableView(&scrollView);
  if ( NS_FAILED(rv))
    return rv;

  if (!scrollView)
  {

    nsCOMPtr<nsIPresShell> presShell;

    rv = GetPresShell(getter_AddRefs(presShell));

    if (NS_FAILED(rv))
      return rv;

    if (!presShell)
      return NS_ERROR_NULL_POINTER;

    nsIViewManager* viewManager = presShell->GetViewManager();

    if (!viewManager)
      return NS_ERROR_NULL_POINTER;

    //
    // nsIViewManager::GetRootScrollableView() does not
    // AddRef the pointer it returns.
    //
    return viewManager->GetRootScrollableView(aScrollableView);
  }
  else //SCROLLVIEW_FROM_FRAME
  {
    *aScrollableView = scrollView;
  }

  return rv;
}

nsresult
nsTypedSelection::GetFrameToScrolledViewOffsets(nsIScrollableView *aScrollableView, nsIFrame *aFrame, nscoord *aX, nscoord *aY)
{
  nsresult rv = NS_OK;
  if (!mFrameSelection)
    return NS_ERROR_FAILURE;//nothing to do

  if (!aScrollableView || !aFrame || !aX || !aY) {
    return NS_ERROR_NULL_POINTER;
  }

  *aX = 0;
  *aY = 0;

  nsIView*  scrolledView;
  nsPoint   offset;
  nsIView*  closestView;
          
  // Determine the offset from aFrame to the scrolled view. We do that by
  // getting the offset from its closest view and then walking up
  aScrollableView->GetScrolledView(scrolledView);
  nsIFocusTracker *tracker = mFrameSelection->GetTracker();

  if (!tracker)
    return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsIPresContext> presContext;
  tracker->GetPresContext(getter_AddRefs(presContext));
  aFrame->GetOffsetFromView(presContext, offset, &closestView);

  // XXX Deal with the case where there is a scrolled element, e.g., a
  // DIV in the middle...
  while (closestView && closestView != scrolledView) {
    // Update the offset
    offset += closestView->GetPosition();

    // Get its parent view
    closestView = closestView->GetParent();
  }

  *aX = offset.x;
  *aY = offset.y;

  return rv;
}

nsresult
nsTypedSelection::GetPointFromOffset(nsIFrame *aFrame, PRInt32 aContentOffset, nsPoint *aPoint)
{
  nsresult rv = NS_OK;
  if (!mFrameSelection)
    return NS_ERROR_FAILURE;//nothing to do
  if (!aFrame || !aPoint)
    return NS_ERROR_NULL_POINTER;

  aPoint->x = 0;
  aPoint->y = 0;

  //
  // Retrieve the device context. We need one to create
  // a rendering context.
  //

  nsIFocusTracker *tracker = mFrameSelection->GetTracker();

  if (!tracker)
    return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsIPresContext> presContext;

  rv = tracker->GetPresContext(getter_AddRefs(presContext));

  if (NS_FAILED(rv))
    return rv;

  if (!presContext)
    return NS_ERROR_NULL_POINTER;
  
  nsCOMPtr<nsIDeviceContext> deviceContext;

  rv = presContext->GetDeviceContext(getter_AddRefs(deviceContext));

  if (NS_FAILED(rv))
    return rv;

  if (!deviceContext)
    return NS_ERROR_NULL_POINTER;

  //
  // Now get the closest view with a widget so we can create
  // a rendering context.
  //

  nsIWidget* widget = nsnull;
  nsIView *closestView = nsnull;
  nsPoint offset(0, 0);

  rv = aFrame->GetOffsetFromView(presContext, offset, &closestView);

  while (!widget && closestView)
  {
    widget = closestView->GetWidget();

    if (!widget)
    {
      closestView = closestView->GetParent();
    }
  }

  if (!closestView)
    return NS_ERROR_FAILURE;

  //
  // Create a rendering context. This context is used by text frames
  // to calculate text widths so it can figure out where the point is
  // in the frame.
  //

  nsCOMPtr<nsIRenderingContext> rendContext;

  rv = deviceContext->CreateRenderingContext(closestView, *getter_AddRefs(rendContext));
  
  if (NS_FAILED(rv))
    return rv;

  if (!rendContext)
    return NS_ERROR_NULL_POINTER;

  //
  // Now get the point and return!
  //

  rv = aFrame->GetPointFromOffset(presContext, rendContext, aContentOffset, aPoint);

  return rv;
}

nsresult
nsTypedSelection::GetSelectionRegionRectAndScrollableView(SelectionRegion aRegion, nsRect *aRect, nsIScrollableView **aScrollableView)
{
  nsresult result = NS_OK;
  if (!mFrameSelection)
    return NS_ERROR_FAILURE;//nothing to do

  if (!aRect || !aScrollableView)
    return NS_ERROR_NULL_POINTER;

  // Init aRect:

  aRect->x = 0;
  aRect->y = 0;
  aRect->width  = 0;
  aRect->height = 0;

  *aScrollableView = 0;

  nsIDOMNode *node       = 0;
  PRInt32     nodeOffset = 0;
  PRBool      isEndNode  = PR_TRUE;
  nsIFrame   *frame      = 0;

  switch (aRegion)
  {
  case nsISelectionController::SELECTION_ANCHOR_REGION:
    node       = FetchAnchorNode();
    nodeOffset = FetchAnchorOffset();
    isEndNode  = GetDirection() == eDirPrevious;
    break;
  case nsISelectionController::SELECTION_FOCUS_REGION:
    node       = FetchFocusNode();
    nodeOffset = FetchFocusOffset();
    isEndNode  = GetDirection() == eDirNext;
    break;
  default:
    return NS_ERROR_FAILURE;
  }

  if (!node)
    return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsIContent> content = do_QueryInterface(node);
  PRInt32 frameOffset = 0;

  if (content)
  {
    nsIFrameSelection::HINT hint;
    mFrameSelection->GetHint(&hint);
    result = mFrameSelection->GetFrameForNodeOffset(content, nodeOffset, hint, &frame, &frameOffset);
  }
  else
    result = NS_ERROR_FAILURE;

  if(NS_FAILED(result))
    return result;

  if (!frame)
    return NS_ERROR_NULL_POINTER;

  //
  // Get the frame's scrollable view.
  //

  nsCOMPtr<nsIPresContext> presContext;

  result = GetPresContext(getter_AddRefs(presContext));

  if (NS_FAILED(result))
    return result;

  if (!presContext)
    return NS_ERROR_FAILURE;


  nsIFrame *parentWithView = frame->GetAncestorWithView();

  if (!parentWithView)
    return NS_ERROR_FAILURE;

  nsIView* view = parentWithView->GetView();

  result = GetClosestScrollableView(view, aScrollableView);

  if (NS_FAILED(result))
    return result;

  if (!*aScrollableView)
    return NS_OK;

  //
  // Figure out what node type we have, then get the
  // appropriate rect for it's nodeOffset.
  //

  PRUint16 nodeType = nsIDOMNode::ELEMENT_NODE;

  result = node->GetNodeType(&nodeType);

  if (NS_FAILED(result))
    return NS_ERROR_NULL_POINTER;

  if (nodeType == nsIDOMNode::TEXT_NODE)
  {
    nsIFrame *childFrame = 0;
    frameOffset  = 0;

    result = frame->GetChildFrameContainingOffset(nodeOffset, mFrameSelection->mHint, &frameOffset, &childFrame);

    if (NS_FAILED(result))
      return result;

    if (!childFrame)
      return NS_ERROR_NULL_POINTER;

    frame = childFrame;

    //
    // Get the x coordinate of the offset into the text frame.
    // The x coordinate will be relative to the frame's origin,
    // so we'll have to translate it into the root view's coordinate
    // system.
    //
    nsPoint pt;
    result = GetCachedFrameOffset(frame, nodeOffset, pt);

    if (NS_FAILED(result))
      return result;
    
    //
    // Get the frame's rect.
    //
    *aRect = frame->GetRect();

    //
    // Translate the frame's rect into root view coordinates.
    //
    result = GetFrameToScrolledViewOffsets(*aScrollableView, frame, &aRect->x, &aRect->y);

    if (NS_FAILED(result))
      return result;

    //
    // Now add the offset's x coordinate.
    //
    aRect->x += pt.x;

    //
    // Adjust the width of the rect to account for any neccessary
    // padding!
    //

    const nsIView* clipView = 0;

    result = (*aScrollableView)->GetClipView(&clipView);

    if (NS_FAILED(result))
      return result;

    nsRect clipRect = clipView->GetBounds();

    result = (*aScrollableView)->GetScrollPosition(clipRect.x, clipRect.y);

    if (NS_FAILED(result))
      return result;

    //
    // If the point we are interested is outside the clip
    // region, we will scroll it into view with a padding
    // equal to a quarter of the clip's width.
    //

    PRInt32 pad = clipRect.width >> 2;

    if (pad <= 0)
      pad = 3; // Arbitrary

    if (aRect->x >= clipRect.XMost())
      aRect->width = pad;
    else if (aRect->x <= clipRect.x)
    {
      aRect->x -= pad;
      aRect->width = pad;
    }
    else
      aRect->width = 60; // Arbitrary

    //
    // Clip the x dimensions of aRect so that they are
    // completely within the bounds of the scrolledView.
    // This helps avoid unnecessary scrolling of parent
    // scrolled views.
    //
    // Note that aRect is in the coordinate system
    // of the scrolledView, so there is no need to take
    // into account scrolledView's x and y position.
    // We can just assume that (0,0) corresponds to the
    // upper left corner, and (svRect.width, svRect.height)
    // the lower right corner of the scrolledView.
    //

    nsIView* scrolledView = 0;

    result = (*aScrollableView)->GetScrolledView(scrolledView);

    if (NS_FAILED(result))
      return result;

    nsRect svRect = scrolledView->GetBounds();

    if (aRect->x < 0)
      aRect->x = 0;
    else if (aRect->x >= svRect.width)
      aRect->x = svRect.width - 1;

    if (aRect->XMost() > svRect.width)
      aRect->width = svRect.width - aRect->x;
  }
  else
  {
    //
    // Must be a non-text frame, just scroll the frame
    // into view.
    //
    *aRect = frame->GetRect();

    result = GetFrameToScrolledViewOffsets(*aScrollableView, frame, &aRect->x, &aRect->y);
  }

  return result;
}

nsresult
nsTypedSelection::ScrollRectIntoView(nsIScrollableView *aScrollableView,
                              nsRect& aRect,
                              PRIntn  aVPercent, 
                              PRIntn  aHPercent,
                              PRBool aScrollParentViews)
{
  nsresult rv = NS_OK;
  if (!mFrameSelection)
    return NS_OK;//nothing to do

  if (!aScrollableView)
    return NS_ERROR_NULL_POINTER;

  // Determine the visible rect in the scrolled view's coordinate space.
  // The size of the visible area is the clip view size
  const nsIView*  clipView;

  aScrollableView->GetClipView(&clipView);
  nsRect visibleRect = clipView->GetBounds();
  aScrollableView->GetScrollPosition(visibleRect.x, visibleRect.y);

  // The actual scroll offsets
  nscoord scrollOffsetX = visibleRect.x;
  nscoord scrollOffsetY = visibleRect.y;

  // See how aRect should be positioned vertically
  if (NS_PRESSHELL_SCROLL_ANYWHERE == aVPercent) {
    // The caller doesn't care where aRect is positioned vertically,
    // so long as it's fully visible
    if (aRect.y < visibleRect.y) {
      // Scroll up so aRect's top edge is visible
      scrollOffsetY = aRect.y;
    } else if (aRect.YMost() > visibleRect.YMost()) {
      // Scroll down so aRect's bottom edge is visible. Make sure
      // aRect's top edge is still visible
      scrollOffsetY += aRect.YMost() - visibleRect.YMost();
      if (scrollOffsetY > aRect.y) {
        scrollOffsetY = aRect.y;
      }
    }
  } else {
    // Align the aRect edge according to the specified percentage
    nscoord frameAlignY = aRect.y + (aRect.height * aVPercent) / 100;
    scrollOffsetY = frameAlignY - (visibleRect.height * aVPercent) / 100;
  }

  // See how the aRect should be positioned horizontally
  if (NS_PRESSHELL_SCROLL_ANYWHERE == aHPercent) {
    // The caller doesn't care where the aRect is positioned horizontally,
    // so long as it's fully visible
    if (aRect.x < visibleRect.x) {
      // Scroll left so the aRect's left edge is visible
      scrollOffsetX = aRect.x;
    } else if (aRect.XMost() > visibleRect.XMost()) {
      // Scroll right so the aRect's right edge is visible. Make sure the
      // aRect's left edge is still visible
      scrollOffsetX += aRect.XMost() - visibleRect.XMost();
      if (scrollOffsetX > aRect.x) {
        scrollOffsetX = aRect.x;
      }
    }
      
  } else {
    // Align the aRect edge according to the specified percentage
    nscoord frameAlignX = aRect.x + (aRect.width * aHPercent) / 100;
    scrollOffsetX = frameAlignX - (visibleRect.width * aHPercent) / 100;
  }

  aScrollableView->ScrollTo(scrollOffsetX, scrollOffsetY, NS_VMREFRESH_IMMEDIATE);

  if (aScrollParentViews)
  {
    //
    // Get aScrollableView's scrolled view.
    //

    nsIView *scrolledView = 0;

    rv = aScrollableView->GetScrolledView(scrolledView);

    if (NS_FAILED(rv))
      return rv;

    if (!scrolledView)
      return NS_ERROR_FAILURE;

    //
    // Check if aScrollableRect has a parent scrollable view!
    //

    nsIView *view = 0;
    rv = CallQueryInterface(aScrollableView, &view);
    if (!view)
      return rv;

    view = view->GetParent();

    if (view)
    {
      nsIScrollableView *parentSV = 0;

      rv = GetClosestScrollableView(view, &parentSV);

      if (NS_FAILED(rv))
        return rv;

      if (parentSV)
      {
        //
        // We have a parent scrollable view, so now map aRect
        // into it's scrolled view's coordinate space.
        //
        
        nsRect newRect;

        rv = parentSV->GetScrolledView(view);

        if (NS_FAILED(rv))
          return rv;

        if (!view)
          return NS_ERROR_FAILURE;

        rv = GetViewAncestorOffset(scrolledView, view, &newRect.x, &newRect.y);

        if (NS_FAILED(rv))
          return rv;

        newRect.x     += aRect.x;
        newRect.y     += aRect.y;
        newRect.width  = aRect.width;
        newRect.height = aRect.height;

        //
        // Now scroll the rect into the parent's view.
        //

        rv = ScrollRectIntoView(parentSV, newRect, aVPercent, aHPercent, aScrollParentViews);
      }
    }
  }

  return rv;
}

static void PR_CALLBACK HandlePLEvent(nsScrollSelectionIntoViewEvent* aEvent);
static void PR_CALLBACK DestroyPLEvent(nsScrollSelectionIntoViewEvent* aEvent);

struct nsScrollSelectionIntoViewEvent : public PLEvent {
  nsScrollSelectionIntoViewEvent(nsTypedSelection *aTypedSelection, SelectionRegion aRegion) {
    if (!aTypedSelection)
      return;

    mTypedSelection = aTypedSelection;
    mRegion = aRegion;

    PL_InitEvent(this, aTypedSelection,
                 (PLHandleEventProc) ::HandlePLEvent,
                 (PLDestroyEventProc) ::DestroyPLEvent);
  }

  ~nsScrollSelectionIntoViewEvent() {}

  void HandleEvent() {
    mTypedSelection->mScrollEventPosted = PR_FALSE;

    if (!mTypedSelection)
      return;

    mTypedSelection->ScrollIntoView(mRegion, PR_TRUE);
  }

  nsTypedSelection *mTypedSelection;
  SelectionRegion   mRegion;
};

static void PR_CALLBACK HandlePLEvent(nsScrollSelectionIntoViewEvent* aEvent)
{
  NS_ASSERTION(nsnull != aEvent,"Event is null");
  aEvent->HandleEvent();
}

static void PR_CALLBACK DestroyPLEvent(nsScrollSelectionIntoViewEvent* aEvent)
{
  NS_ASSERTION(nsnull != aEvent,"Event is null");
  delete aEvent;
}

nsresult
nsTypedSelection::PostScrollSelectionIntoViewEvent(SelectionRegion aRegion)
{
  static NS_DEFINE_CID(kEventQueueServiceCID, NS_EVENTQUEUESERVICE_CID);

  if (!mEventQueue) {
    nsresult rv;

    // Cache the event queue of the current UI thread
    nsCOMPtr<nsIEventQueueService> eventService = do_GetService(kEventQueueServiceCID, &rv);
    if (NS_SUCCEEDED(rv) && (nsnull != eventService)) {  // XXX this implies that the UI is the current thread.
      rv = eventService->GetThreadEventQueue(NS_CURRENT_THREAD, getter_AddRefs(mEventQueue));
    }
  }

  if (mEventQueue) {
    if (mScrollEventPosted) {
      // We've already posted an event, revoke it and
      // place a new one at the end of the queue to make
      // sure that any new pending reflow events are processed
      // before we scroll. This will insure that we scroll
      // to the correct place on screen.

      mEventQueue->RevokeEvents(this);
      mScrollEventPosted = PR_FALSE;
    }

    nsScrollSelectionIntoViewEvent *ev = new nsScrollSelectionIntoViewEvent(this, aRegion);
    if (ev) {
      mEventQueue->PostEvent(ev);
      mScrollEventPosted = PR_TRUE;
      return NS_OK;
    }
  }

  return NS_ERROR_FAILURE;
}

NS_IMETHODIMP
nsTypedSelection::ScrollIntoView(SelectionRegion aRegion, PRBool aIsSynchronous)
{
  nsresult result;
  if (!mFrameSelection)
    return NS_OK;//nothing to do

  if (mFrameSelection->GetBatching())
    return NS_OK;

  if (!aIsSynchronous)
    return PostScrollSelectionIntoViewEvent(aRegion);

  //
  // Shut the caret off before scrolling to avoid
  // leaving caret turds on the screen!
  //
  nsCOMPtr<nsIPresShell> presShell;
  result = GetPresShell(getter_AddRefs(presShell));
  if (NS_FAILED(result))
    return result;
  nsCOMPtr<nsICaret> caret;
  presShell->GetCaret(getter_AddRefs(caret));
  if (caret)
  {
    StCaretHider  caretHider(caret);      // stack-based class hides and shows the caret

    //
    // Scroll the selection region into view.
    //

    nsRect rect;
    nsIScrollableView *scrollableView = 0;

    result = GetSelectionRegionRectAndScrollableView(aRegion, &rect, &scrollableView);

    if (NS_FAILED(result))
      return result;

    //
    // It's ok if we don't have a scrollable view, just return early.
    //
    if (!scrollableView)
      return NS_OK;

    result = ScrollRectIntoView(scrollableView, rect, NS_PRESSHELL_SCROLL_ANYWHERE, NS_PRESSHELL_SCROLL_ANYWHERE, PR_TRUE);
  }
  return result;
}



NS_IMETHODIMP
nsTypedSelection::AddSelectionListener(nsISelectionListener* aNewListener)
{
  if (!aNewListener)
    return NS_ERROR_NULL_POINTER;
  return mSelectionListeners.AppendObject(aNewListener) ? NS_OK : NS_ERROR_FAILURE;      // addrefs
}



NS_IMETHODIMP
nsTypedSelection::RemoveSelectionListener(nsISelectionListener* aListenerToRemove)
{
  if (!aListenerToRemove )
    return NS_ERROR_NULL_POINTER;
  return mSelectionListeners.RemoveObject(aListenerToRemove) ? NS_OK : NS_ERROR_FAILURE; // releases
}


nsresult
nsTypedSelection::NotifySelectionListeners()
{
  if (!mFrameSelection)
    return NS_OK;//nothing to do
 
  if (mFrameSelection->GetBatching()){
    mFrameSelection->SetDirty();
    return NS_OK;
  }
  PRInt32 cnt = mSelectionListeners.Count();
  
  nsCOMPtr<nsIDOMDocument> domdoc;
  nsCOMPtr<nsIDocument> doc;
  nsCOMPtr<nsIPresShell> shell;
  nsresult rv = GetPresShell(getter_AddRefs(shell));
  if (NS_SUCCEEDED(rv) && shell)
  {
    rv = shell->GetDocument(getter_AddRefs(doc));
    if (NS_FAILED(rv))
      doc = 0;
    domdoc = do_QueryInterface(doc);
  }
  short reason = mFrameSelection->PopReason();
  for (PRInt32 i = 0; i < cnt; i++)
  {
    nsISelectionListener* thisListener = mSelectionListeners[i];
    if (thisListener)
      thisListener->NotifySelectionChanged(domdoc, this, reason);
  }
  return NS_OK;
}

NS_IMETHODIMP
nsTypedSelection::StartBatchChanges()
{
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  return mFrameSelection->StartBatchChanges();
}



NS_IMETHODIMP
nsTypedSelection::EndBatchChanges()
{
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  return mFrameSelection->EndBatchChanges();
}



NS_IMETHODIMP
nsTypedSelection::DeleteFromDocument()
{
  if (!mFrameSelection)
    return NS_OK;//nothing to do
  return mFrameSelection->DeleteFromDocument();
}

/** SelectionLanguageChange modifies the cursor Bidi level after a change in keyboard direction
 *  @param aLangRTL is PR_TRUE if the new language is right-to-left or PR_FALSE if the new language is left-to-right
 */
NS_IMETHODIMP
nsTypedSelection::SelectionLanguageChange(PRBool aLangRTL)
{
  nsresult result;
  nsCOMPtr<nsIDOMNode>  focusNode;
  nsCOMPtr<nsIContent> focusContent;
  PRInt32 focusOffset;
  nsIFrame *focusFrame = 0;

  focusOffset = FetchFocusOffset();
  focusNode = FetchFocusNode();
  result = GetPrimaryFrameForFocusNode(&focusFrame, nsnull);
  if (NS_FAILED(result) || !focusFrame)
    return result?result:NS_ERROR_FAILURE;

  PRInt32 frameStart, frameEnd;
  focusFrame->GetOffsets(frameStart, frameEnd);
  nsCOMPtr<nsIPresContext> context;
  PRUint8 level, levelBefore, levelAfter;
  result = GetPresContext(getter_AddRefs(context));
  if (NS_FAILED(result) || !context)
    return result?result:NS_ERROR_FAILURE;

  focusFrame->GetBidiProperty(context, nsLayoutAtoms::embeddingLevel, (void**)&level, sizeof(level));
  if ((focusOffset != frameStart) && (focusOffset != frameEnd))
    // the cursor is not at a frame boundary, so the level of both the characters (logically) before and after the cursor
    //  is equal to the frame level
    levelBefore = levelAfter = level;
  else {
    // the cursor is at a frame boundary, so use GetPrevNextBidiLevels to find the level of the characters
    //  before and after the cursor
    nsIFrame* frameBefore = nsnull;
    nsIFrame* frameAfter = nsnull;
    focusContent = do_QueryInterface(focusNode);
    /*
    nsIFrameSelection::HINT hint;

    if ((focusOffset == frameStart && level)        // beginning of an RTL frame
        || (focusOffset == frameEnd && !level)) {   // end of an LTR frame
      hint = nsIFrameSelection::HINTRIGHT;
    }
    else {                                          // end of an RTL frame or beginning of an LTR frame
      hint = nsIFrameSelection::HINTLEFT;
    }
    mFrameSelection->SetHint(hint);
    */
    mFrameSelection->GetPrevNextBidiLevels(context, focusContent, focusOffset, &frameBefore, &frameAfter, &levelBefore, &levelAfter);
  }

  nsIPresShell* shell = context->GetPresShell();
  if (!shell)
    return NS_ERROR_FAILURE;

  if ((levelBefore & 1) == (levelAfter & 1)) {
    // if cursor is between two characters with the same orientation, changing the keyboard language
    //  must toggle the cursor level between the level of the character with the lowest level
    //  (if the new language corresponds to the orientation of that character) and this level plus 1
    //  (if the new language corresponds to the opposite orientation)
    if ((level != levelBefore) && (level != levelAfter))
      level = PR_MIN(levelBefore, levelAfter);
    if ((level & 1) == aLangRTL)
      shell->SetCaretBidiLevel(level);
    else
      shell->SetCaretBidiLevel(level + 1);
  }
  else {
    // if cursor is between characters with opposite orientations, changing the keyboard language must change
    //  the cursor level to that of the adjacent character with the orientation corresponding to the new language.
    if ((levelBefore & 1) == aLangRTL)
      shell->SetCaretBidiLevel(levelBefore);
    else
      shell->SetCaretBidiLevel(levelAfter);
  }
  return NS_OK;
}