pjs/layout/base/nsCaret.h

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/* the caret is the text cursor used, e.g., when editing */

#include "nsCoord.h"
#include "nsISelectionListener.h"
#include "nsIRenderingContext.h"
#include "nsITimer.h"
#include "nsICaret.h"
#include "nsWeakPtr.h"
#ifdef IBMBIDI
#include "nsIBidiKeyboard.h"
#endif

class nsIView;

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

class nsCaret : public nsICaret,
                public nsISelectionListener
{
  public:

                  nsCaret();
    virtual       ~nsCaret();
        
    NS_DECL_ISUPPORTS

  public:
  
    // nsICaret interface
    NS_IMETHOD    Init(nsIPresShell *inPresShell);
    NS_IMETHOD    Terminate();

    NS_IMETHOD    GetCaretDOMSelection(nsISelection **outDOMSel);
    NS_IMETHOD    SetCaretDOMSelection(nsISelection *inDOMSel);
    NS_IMETHOD    GetCaretVisible(PRBool *outMakeVisible);
    NS_IMETHOD    SetCaretVisible(PRBool intMakeVisible);
    NS_IMETHOD    SetCaretReadOnly(PRBool inMakeReadonly);
    NS_IMETHOD    GetCaretCoordinates(EViewCoordinates aRelativeToType, nsISelection *inDOMSel, nsRect* outCoordinates, PRBool* outIsCollapsed, nsIView **outView);
    NS_IMETHOD    EraseCaret();

    NS_IMETHOD    SetVisibilityDuringSelection(PRBool aVisibility);
    NS_IMETHOD    DrawAtPosition(nsIDOMNode* aNode, PRInt32 aOffset);

    //nsISelectionListener interface
    NS_DECL_NSISELECTIONLISTENER
                              
    static void   CaretBlinkCallback(nsITimer *aTimer, void *aClosure);
  
    NS_IMETHOD    GetCaretFrameForNodeOffset (nsIContent* aContentNode, PRInt32 aOffset, nsIFrameSelection::HINT aFrameHint, PRUint8 aBidiLevel,
                                              nsIFrame** aReturnFrame, PRInt32* aReturnOffset);
  protected:

    void          KillTimer();
    nsresult      PrimeTimer();
    
    nsresult      StartBlinking();
    nsresult      StopBlinking();
    
    void          GetViewForRendering(nsIFrame *caretFrame, EViewCoordinates coordType, nsPoint &viewOffset, nsRect& outClipRect, nsIView **outRenderingView, nsIView **outRelativeView);
    PRBool        DrawAtPositionWithHint(nsIDOMNode* aNode, PRInt32 aOffset, nsIFrameSelection::HINT aFrameHint, PRUint8 aBidiLevel);
    PRBool        MustDrawCaret();
    void          DrawCaret();
    void          DrawCaretAfterBriefDelay();
    void          GetCaretRectAndInvert(nsIFrame* aFrame, PRInt32 aFrameOffset);
    void          ToggleDrawnStatus() {   mDrawn = !mDrawn; }

protected:

    nsWeakPtr             mPresShell;
    nsWeakPtr             mDomSelectionWeak;

    nsCOMPtr<nsITimer>              mBlinkTimer;
    nsCOMPtr<nsIRenderingContext>   mRendContext;

    PRUint32              mBlinkRate;         // time for one cyle (off then on), in milliseconds

    nscoord               mCaretTwipsWidth;   // caret width in twips. this gets calculated laziiy
    nscoord               mBidiIndicatorTwipsSize;   // width and height of bidi indicator

    PRPackedBool          mVisible;           // is the caret blinking
    PRPackedBool          mDrawn;             // this should be mutable
    PRPackedBool          mReadOnly;          // it the caret in readonly state (draws differently)      
    PRPackedBool          mShowDuringSelection; // show when text is selected

    nsRect                mCaretRect;         // the last caret rect
    nsIView*              mLastCaretView;     // last view that we used for drawing. Cached so we can tell when we need to make a new RC
    nsCOMPtr<nsIContent>  mLastContent;       // store the content the caret was last requested to be drawn in (by DrawAtPosition()/DrawCaret()),
                                              // note that this can be different than where it was actually drawn (anon <BR> in text control)
    PRInt32               mLastContentOffset; // the offset for the last request
    nsIFrameSelection::HINT mLastHint;        // the hint associated with the last request, see also mLastBidiLevel below
#ifdef IBMBIDI
    nsRect                mHookRect;          // directional hook on the caret
    nsCOMPtr<nsIBidiKeyboard> mBidiKeyboard;  // Bidi keyboard object to set and query keyboard language
    PRUint8               mLastBidiLevel;     // saved bidi level of the last draw request, to use when we erase
    PRPackedBool          mKeyboardRTL;       // is the keyboard language right-to-left
#endif
};