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 * The Original Code is mozilla.org code.
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 *
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#ifndef nsEventStateManager_h__
#define nsEventStateManager_h__

#include "nsIEventStateManager.h"
#include "nsGUIEvent.h"
#include "nsIContent.h"
#include "nsIPref.h"
#include "nsIObserver.h"
#include "nsWeakReference.h"
#include "nsHashtable.h"
#include "nsITimer.h"

class nsIDocument;
class nsIScrollableView;
class nsIPresShell;
class nsIFrameSelection;
class nsIDocShell;
class nsIDocShellTreeNode;
class nsIDocShellTreeItem;

// mac uses click-hold context menus, a holdover from 4.x
#if defined(XP_MAC) || defined(XP_MACOSX)
#define CLICK_HOLD_CONTEXT_MENUS 1
#endif


/*
 * Event listener manager
 */

class nsEventStateManager : public nsSupportsWeakReference,
                            public nsIEventStateManager,
                            public nsIObserver
{

public:
  nsEventStateManager();
  virtual ~nsEventStateManager();

  NS_DECL_ISUPPORTS
  NS_DECL_NSIOBSERVER

  NS_IMETHOD Init();
  nsresult Shutdown();

  /* The PreHandleEvent method is called before event dispatch to either
   * the DOM or frames.  Any processing which must not be prevented or
   * cancelled should occur here.  Any processing which is intended to
   * be conditional based on either DOM or frame processing should occur in
   * PostHandleEvent.  Any centralized event processing which must occur before
   * DOM or frame event handling should occur here as well.
   */
  NS_IMETHOD PreHandleEvent(nsIPresContext* aPresContext,
                         nsEvent *aEvent,
                         nsIFrame* aTargetFrame,
                         nsEventStatus* aStatus,
                         nsIView* aView);

  /* The PostHandleEvent method should contain all system processing which
   * should occur conditionally based on DOM or frame processing.  It should
   * also contain any centralized event processing which must occur after
   * DOM and frame processing.
   */
  NS_IMETHOD PostHandleEvent(nsIPresContext* aPresContext,
                             nsEvent *aEvent,
                             nsIFrame* aTargetFrame,
                             nsEventStatus* aStatus,
                             nsIView* aView);

  NS_IMETHOD SetPresContext(nsIPresContext* aPresContext);
  NS_IMETHOD ClearFrameRefs(nsIFrame* aFrame);

  NS_IMETHOD GetEventTarget(nsIFrame **aFrame);
  NS_IMETHOD GetEventTargetContent(nsEvent* aEvent, nsIContent** aContent);
  NS_IMETHOD GetEventRelatedContent(nsIContent** aContent);

  NS_IMETHOD GetContentState(nsIContent *aContent, PRInt32& aState);
  NS_IMETHOD SetContentState(nsIContent *aContent, PRInt32 aState);
  NS_IMETHOD GetFocusedContent(nsIContent **aContent);
  NS_IMETHOD SetFocusedContent(nsIContent* aContent);
  NS_IMETHOD ContentRemoved(nsIContent* aContent);
  NS_IMETHOD EventStatusOK(nsGUIEvent* aEvent, PRBool *aOK);

  // This is an experiement and may be temporary
  NS_IMETHOD ConsumeFocusEvents(PRBool aDoConsume) { mConsumeFocusEvents = aDoConsume; return NS_OK; }

  // Access Key Registration
  NS_IMETHOD RegisterAccessKey(nsIFrame * aFrame, nsIContent* aContent, PRUint32 aKey);
  NS_IMETHOD UnregisterAccessKey(nsIFrame * aFrame, nsIContent* aContent, PRUint32 aKey);

  NS_IMETHOD SetCursor(PRInt32 aCursor, nsIWidget* aWidget, PRBool aLockCursor);

  //Method for centralized distribution of new DOM events
  NS_IMETHOD DispatchNewEvent(nsISupports* aTarget, nsIDOMEvent* aEvent, PRBool *aPreventDefault);

  NS_IMETHOD ShiftFocus(PRBool aForward, nsIContent* aStart=nsnull);

  NS_IMETHOD ResetBrowseWithCaret(PRBool *aBrowseWithCaret);

  NS_IMETHOD MoveFocusToCaret(PRBool aCanFocusDoc, PRBool *aIsSelectionWithFocus);
  NS_IMETHOD MoveCaretToFocus();

protected:
  void UpdateCursor(nsIPresContext* aPresContext, nsEvent* aEvent, nsIFrame* aTargetFrame, nsEventStatus* aStatus);
  void GenerateMouseEnterExit(nsIPresContext* aPresContext, nsGUIEvent* aEvent);
  void GenerateDragDropEnterExit(nsIPresContext* aPresContext, nsGUIEvent* aEvent);
  NS_IMETHOD SetClickCount(nsIPresContext* aPresContext, nsMouseEvent *aEvent, nsEventStatus* aStatus);
  NS_IMETHOD CheckForAndDispatchClick(nsIPresContext* aPresContext, nsMouseEvent *aEvent, nsEventStatus* aStatus);
  PRBool ChangeFocus(nsIContent* aFocus);
  NS_IMETHOD GetNextTabbableContent(nsIContent* aRootContent, nsIFrame* aFrame, PRBool forward, PRBool ignoreTabIndex, nsIContent** aResult);

  void TabIndexFrom(nsIContent *aFrom, PRInt32 *aOutIndex);
  PRInt32 GetNextTabIndex(nsIContent* aParent, PRBool foward);
  NS_IMETHOD SendFocusBlur(nsIPresContext* aPresContext, nsIContent *aContent, PRBool aEnsureWindowHasFocus);
  PRBool CheckDisabled(nsIContent* aContent);
  void EnsureDocument(nsIPresShell* aPresShell);
  void EnsureDocument(nsIPresContext* aPresContext);
  void FlushPendingEvents(nsIPresContext* aPresContext);

  //---------------------------------------------
  // DocShell Focus Traversal Methods
  //---------------------------------------------

  nsresult ShiftFocusInternal(PRBool aForward, nsIContent* aStart = nsnull);
  void TabIntoDocument(nsIDocShell* aDocShell, PRBool aForward);
  void ShiftFocusByDoc(PRBool forward);
  PRBool IsFrameSetDoc(nsIDocShell* aDocShell);
  PRBool IsIFrameDoc(nsIDocShell* aDocShell);
  PRBool IsShellVisible(nsIDocShell* aShell);
  void GetLastChildDocShell(nsIDocShellTreeItem* aItem,
                            nsIDocShellTreeItem** aResult);
  void GetNextDocShell(nsIDocShellTreeNode* aNode,
                       nsIDocShellTreeItem** aResult);
  void GetPrevDocShell(nsIDocShellTreeNode* aNode,
                       nsIDocShellTreeItem** aResult);

  // These functions are for mousewheel scrolling
  nsIScrollableView* GetNearestScrollingView(nsIView* aView);
  nsresult GetParentScrollingView(nsMouseScrollEvent* aEvent,
                                  nsIPresContext* aPresContext,
                                  nsIFrame* &targetOuterFrame,
                                  nsIPresContext* &presCtxOuter);
  nsresult DoWheelScroll(nsIPresContext* aPresContext,
                         nsIFrame* aTargetFrame,
                         nsMouseScrollEvent* msEvent, PRInt32 numLines,
                         PRBool scrollPage, PRBool aUseTargetFrame);
  void ForceViewUpdate(nsIView* aView);
  nsresult getPrefService();
  nsresult ChangeTextSize(PRInt32 change);
  // end mousewheel functions

  // routines for the d&d gesture tracking state machine
  void BeginTrackingDragGesture ( nsIPresContext* aPresContext, nsGUIEvent* inDownEvent, nsIFrame* inDownFrame ) ;
  void StopTrackingDragGesture ( ) ;
  void GenerateDragGesture ( nsIPresContext* aPresContext, nsGUIEvent *aEvent ) ;
  PRBool IsTrackingDragGesture ( ) const { return mIsTrackingDragGesture; }

  PRBool mSuppressFocusChange; // Used only for Ender text fields to suppress a focus firing on mouse down

  nsresult SetCaretEnabled(nsIPresShell *aPresShell, PRBool aVisibility);
  nsresult SetContentCaretVisible(nsIPresShell* aPresShell, nsIContent *aContent, PRBool aVisible);
  void FocusElementButNotDocument(nsIContent *aElement);

  // Return the location of the caret
  nsresult GetDocSelectionLocation(nsIContent **startContent, nsIContent **endContent, nsIFrame **startFrame, PRUint32 *startOffset);

  void GetSelection ( nsIFrame* inFrame, nsIPresContext* inPresContext, nsIFrameSelection** outSelection ) ;

  //Any frames here must be checked for validity in ClearFrameRefs
  nsIFrame* mCurrentTarget;
  nsIContent* mCurrentTargetContent;
  nsIContent* mCurrentRelatedContent;
  nsIFrame* mLastMouseOverFrame;
  nsCOMPtr<nsIContent> mLastMouseOverContent;
  nsIFrame* mLastDragOverFrame;

  // member variables for the d&d gesture state machine
  PRBool mIsTrackingDragGesture;
  nsPoint mGestureDownPoint;
  nsIFrame* mGestureDownFrame;

  nsIContent* mLastLeftMouseDownContent;
  nsIContent* mLastMiddleMouseDownContent;
  nsIContent* mLastRightMouseDownContent;

  nsIContent* mActiveContent;
  nsIContent* mHoverContent;
  nsIContent* mDragOverContent;
  nsIContent* mCurrentFocus;
  PRInt32 mCurrentTabIndex;
  nsIWidget * mLastWindowToHaveFocus; // last native window to get focus via the evs
  PRBool      mConsumeFocusEvents;
  PRInt32     mLockCursor;

  // DocShell Traversal Data Memebers
  nsCOMPtr<nsIContent> mLastContentFocus;

  //Anti-recursive stack controls
  nsIContent* mFirstBlurEvent;
  nsIContent* mFirstFocusEvent;
  nsCOMPtr<nsIContent> mFirstMouseOverEventContent;
  nsCOMPtr<nsIContent> mFirstMouseOutEventContent;

  nsIPresContext* mPresContext;      // Not refcnted
  nsIDocument* mDocument;            // [OWNER], but doesn't need to be.
  //Pref for dispatching middle and right clicks to content
  PRBool mLeftClickOnly;

  PRUint32 mLClickCount;
  PRUint32 mMClickCount;
  PRUint32 mRClickCount;

  PRPackedBool mNormalLMouseEventInProcess;

  //Hashtable for accesskey support
  nsSupportsHashtable *mAccessKeys;

  static PRUint32 mInstanceCount;

  // For preferences handling
  nsCOMPtr<nsIPref> mPrefService;
  PRBool m_haveShutdown;

  //Pref for using hierarchical hover (possibly expensive) or not
  PRBool hHover;

  // So we don't have to keep checking accessibility.browsewithcaret pref
  PRBool mBrowseWithCaret;

  // Recursion guard for tabbing
  PRBool mTabbedThroughDocument;

#ifdef CLICK_HOLD_CONTEXT_MENUS
  enum { kClickHoldDelay = 500 } ;        // 500ms == 1/2 second

  void CreateClickHoldTimer ( nsIPresContext* aPresContext, nsGUIEvent* inMouseDownEvent ) ;
  void KillClickHoldTimer ( ) ;
  void FireContextClick ( ) ;
  static void sClickHoldCallback ( nsITimer* aTimer, void* aESM ) ;
  
    // stash a bunch of stuff because we're going through a timer and the event
    // isn't guaranteed to be there later. We don't want to hold strong refs to
    // things because we're alerted to when they are going away in ClearFrameRefs().
  nsPoint mEventPoint, mEventRefPoint;
  nsIWidget* mEventDownWidget;
  nsIPresContext* mEventPresContext;
  nsCOMPtr<nsITimer> mClickHoldTimer;
#endif

};

extern nsresult NS_NewEventStateManager(nsIEventStateManager** aInstancePtrResult);

#endif // nsEventStateManager_h__
