diff -r 000000000000 -r 6474c204b198 accessible/src/base/AccEvent.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/accessible/src/base/AccEvent.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,526 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef _AccEvent_H_
+#define _AccEvent_H_
+
+#include "nsIAccessibleEvent.h"
+
+#include "mozilla/a11y/Accessible.h"
+
+namespace mozilla {
+
+namespace dom {
+class Selection;
+}
+
+namespace a11y {
+
+class DocAccessible;
+
+// Constants used to point whether the event is from user input.
+enum EIsFromUserInput
+{
+  // eNoUserInput: event is not from user input
+  eNoUserInput = 0,
+  // eFromUserInput: event is from user input
+  eFromUserInput = 1,
+  // eAutoDetect: the value should be obtained from event state manager
+  eAutoDetect = -1
+};
+
+/**
+ * Generic accessible event.
+ */
+class AccEvent
+{
+public:
+
+  // Rule for accessible events.
+  // The rule will be applied when flushing pending events.
+  enum EEventRule {
+    // eAllowDupes : More than one event of the same type is allowed.
+    //    This event will always be emitted. This flag is used for events that
+    //    don't support coalescence.
+    eAllowDupes,
+
+     // eCoalesceReorder : For reorder events from the same subtree or the same
+     //    node, only the umbrella event on the ancestor will be emitted.
+    eCoalesceReorder,
+
+     // eCoalesceMutationTextChange : coalesce text change events caused by
+     // tree mutations of the same tree level.
+    eCoalesceMutationTextChange,
+
+    // eCoalesceOfSameType : For events of the same type, only the newest event
+    // will be processed.
+    eCoalesceOfSameType,
+
+    // eCoalesceSelectionChange: coalescence of selection change events.
+    eCoalesceSelectionChange,
+
+    // eCoalesceStateChange: coalesce state change events.
+    eCoalesceStateChange,
+
+    // eCoalesceTextSelChange: coalescence of text selection change events.
+    eCoalesceTextSelChange,
+
+     // eRemoveDupes : For repeat events, only the newest event in queue
+     //    will be emitted.
+    eRemoveDupes,
+
+     // eDoNotEmit : This event is confirmed as a duplicate, do not emit it.
+    eDoNotEmit
+  };
+
+  // Initialize with an nsIAccessible
+  AccEvent(uint32_t aEventType, Accessible* aAccessible,
+           EIsFromUserInput aIsFromUserInput = eAutoDetect,
+           EEventRule aEventRule = eRemoveDupes);
+  virtual ~AccEvent() {}
+
+  // AccEvent
+  uint32_t GetEventType() const { return mEventType; }
+  EEventRule GetEventRule() const { return mEventRule; }
+  bool IsFromUserInput() const { return mIsFromUserInput; }
+  EIsFromUserInput FromUserInput() const
+    { return static_cast<EIsFromUserInput>(mIsFromUserInput); }
+
+  Accessible* GetAccessible() const { return mAccessible; }
+  DocAccessible* GetDocAccessible() const { return mAccessible->Document(); }
+
+  /**
+   * Down casting.
+   */
+  enum EventGroup {
+    eGenericEvent,
+    eStateChangeEvent,
+    eTextChangeEvent,
+    eMutationEvent,
+    eReorderEvent,
+    eHideEvent,
+    eShowEvent,
+    eCaretMoveEvent,
+    eTextSelChangeEvent,
+    eSelectionChangeEvent,
+    eTableChangeEvent,
+    eVirtualCursorChangeEvent
+  };
+
+  static const EventGroup kEventGroup = eGenericEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return 1U << eGenericEvent;
+  }
+
+  /**
+   * Reference counting and cycle collection.
+   */
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(AccEvent)
+  NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(AccEvent)
+
+protected:
+  bool mIsFromUserInput;
+  uint32_t mEventType;
+  EEventRule mEventRule;
+  nsRefPtr<Accessible> mAccessible;
+
+  friend class EventQueue;
+  friend class AccReorderEvent;
+};
+
+
+/**
+ * Accessible state change event.
+ */
+class AccStateChangeEvent: public AccEvent
+{
+public:
+  AccStateChangeEvent(Accessible* aAccessible, uint64_t aState,
+                      bool aIsEnabled,
+                      EIsFromUserInput aIsFromUserInput = eAutoDetect) :
+    AccEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, aAccessible,
+             aIsFromUserInput, eCoalesceStateChange),
+             mState(aState), mIsEnabled(aIsEnabled) { }
+
+  AccStateChangeEvent(Accessible* aAccessible, uint64_t aState) :
+    AccEvent(::nsIAccessibleEvent::EVENT_STATE_CHANGE, aAccessible,
+             eAutoDetect, eCoalesceStateChange), mState(aState)
+    { mIsEnabled = (mAccessible->State() & mState) != 0; }
+
+  // AccEvent
+  static const EventGroup kEventGroup = eStateChangeEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eStateChangeEvent);
+  }
+
+  // AccStateChangeEvent
+  uint64_t GetState() const { return mState; }
+  bool IsStateEnabled() const { return mIsEnabled; }
+
+private:
+  uint64_t mState;
+  bool mIsEnabled;
+
+  friend class EventQueue;
+};
+
+
+/**
+ * Accessible text change event.
+ */
+class AccTextChangeEvent: public AccEvent
+{
+public:
+  AccTextChangeEvent(Accessible* aAccessible, int32_t aStart,
+                     const nsAString& aModifiedText, bool aIsInserted,
+                     EIsFromUserInput aIsFromUserInput = eAutoDetect);
+
+  // AccEvent
+  static const EventGroup kEventGroup = eTextChangeEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eTextChangeEvent);
+  }
+
+  // AccTextChangeEvent
+  int32_t GetStartOffset() const { return mStart; }
+  uint32_t GetLength() const { return mModifiedText.Length(); }
+  bool IsTextInserted() const { return mIsInserted; }
+  void GetModifiedText(nsAString& aModifiedText)
+    { aModifiedText = mModifiedText; }
+
+private:
+  int32_t mStart;
+  bool mIsInserted;
+  nsString mModifiedText;
+
+  friend class EventQueue;
+  friend class AccReorderEvent;
+};
+
+
+/**
+ * Base class for show and hide accessible events.
+ */
+class AccMutationEvent: public AccEvent
+{
+public:
+  AccMutationEvent(uint32_t aEventType, Accessible* aTarget,
+                   nsINode* aTargetNode) :
+    AccEvent(aEventType, aTarget, eAutoDetect, eCoalesceMutationTextChange)
+  {
+    // Don't coalesce these since they are coalesced by reorder event. Coalesce
+    // contained text change events.
+    mParent = mAccessible->Parent();
+  }
+  virtual ~AccMutationEvent() { }
+
+  // Event
+  static const EventGroup kEventGroup = eMutationEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eMutationEvent);
+  }
+
+  // MutationEvent
+  bool IsShow() const { return mEventType == nsIAccessibleEvent::EVENT_SHOW; }
+  bool IsHide() const { return mEventType == nsIAccessibleEvent::EVENT_HIDE; }
+
+protected:
+  nsCOMPtr<nsINode> mNode;
+  nsRefPtr<Accessible> mParent;
+  nsRefPtr<AccTextChangeEvent> mTextChangeEvent;
+
+  friend class EventQueue;
+};
+
+
+/**
+ * Accessible hide event.
+ */
+class AccHideEvent: public AccMutationEvent
+{
+public:
+  AccHideEvent(Accessible* aTarget, nsINode* aTargetNode);
+
+  // Event
+  static const EventGroup kEventGroup = eHideEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccMutationEvent::GetEventGroups() | (1U << eHideEvent);
+  }
+
+  // AccHideEvent
+  Accessible* TargetParent() const { return mParent; }
+  Accessible* TargetNextSibling() const { return mNextSibling; }
+  Accessible* TargetPrevSibling() const { return mPrevSibling; }
+
+protected:
+  nsRefPtr<Accessible> mNextSibling;
+  nsRefPtr<Accessible> mPrevSibling;
+
+  friend class EventQueue;
+};
+
+
+/**
+ * Accessible show event.
+ */
+class AccShowEvent: public AccMutationEvent
+{
+public:
+  AccShowEvent(Accessible* aTarget, nsINode* aTargetNode);
+
+  // Event
+  static const EventGroup kEventGroup = eShowEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccMutationEvent::GetEventGroups() | (1U << eShowEvent);
+  }
+};
+
+
+/**
+ * Class for reorder accessible event. Takes care about
+ */
+class AccReorderEvent : public AccEvent
+{
+public:
+  AccReorderEvent(Accessible* aTarget) :
+    AccEvent(::nsIAccessibleEvent::EVENT_REORDER, aTarget,
+             eAutoDetect, eCoalesceReorder) { }
+  virtual ~AccReorderEvent() { }
+
+  // Event
+  static const EventGroup kEventGroup = eReorderEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eReorderEvent);
+  }
+
+  /**
+   * Get connected with mutation event.
+   */
+  void AddSubMutationEvent(AccMutationEvent* aEvent)
+    { mDependentEvents.AppendElement(aEvent); }
+
+  /**
+   * Do not emit the reorder event and its connected mutation events.
+   */
+  void DoNotEmitAll()
+  {
+    mEventRule = AccEvent::eDoNotEmit;
+    uint32_t eventsCount = mDependentEvents.Length();
+    for (uint32_t idx = 0; idx < eventsCount; idx++)
+      mDependentEvents[idx]->mEventRule = AccEvent::eDoNotEmit;
+  }
+
+  /**
+   * Return true if the given accessible is a target of connected mutation
+   * event.
+   */
+  uint32_t IsShowHideEventTarget(const Accessible* aTarget) const;
+
+protected:
+  /**
+   * Show and hide events causing this reorder event.
+   */
+  nsTArray<AccMutationEvent*> mDependentEvents;
+
+  friend class EventQueue;
+};
+
+
+/**
+ * Accessible caret move event.
+ */
+class AccCaretMoveEvent: public AccEvent
+{
+public:
+  AccCaretMoveEvent(Accessible* aAccessible, int32_t aCaretOffset,
+                    EIsFromUserInput aIsFromUserInput = eAutoDetect) :
+    AccEvent(::nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED, aAccessible,
+             aIsFromUserInput),
+    mCaretOffset(aCaretOffset) { }
+  virtual ~AccCaretMoveEvent() { }
+
+  // AccEvent
+  static const EventGroup kEventGroup = eCaretMoveEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eCaretMoveEvent);
+  }
+
+  // AccCaretMoveEvent
+  int32_t GetCaretOffset() const { return mCaretOffset; }
+
+private:
+  int32_t mCaretOffset;
+};
+
+
+/**
+ * Accessible text selection change event.
+ */
+class AccTextSelChangeEvent : public AccEvent
+{
+public:
+  AccTextSelChangeEvent(HyperTextAccessible* aTarget,
+                        dom::Selection* aSelection,
+                        int32_t aReason);
+  virtual ~AccTextSelChangeEvent();
+
+  // AccEvent
+  static const EventGroup kEventGroup = eTextSelChangeEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eTextSelChangeEvent);
+  }
+
+  // AccTextSelChangeEvent
+
+  /**
+   * Return true if the text selection change wasn't caused by pure caret move.
+   */
+  bool IsCaretMoveOnly() const;
+
+private:
+  nsRefPtr<dom::Selection> mSel;
+  int32_t mReason;
+
+  friend class EventQueue;
+  friend class SelectionManager;
+};
+
+
+/**
+ * Accessible widget selection change event.
+ */
+class AccSelChangeEvent : public AccEvent
+{
+public:
+  enum SelChangeType {
+    eSelectionAdd,
+    eSelectionRemove
+  };
+
+  AccSelChangeEvent(Accessible* aWidget, Accessible* aItem,
+                    SelChangeType aSelChangeType);
+
+  virtual ~AccSelChangeEvent() { }
+
+  // AccEvent
+  static const EventGroup kEventGroup = eSelectionChangeEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eSelectionChangeEvent);
+  }
+
+  // AccSelChangeEvent
+  Accessible* Widget() const { return mWidget; }
+
+private:
+  nsRefPtr<Accessible> mWidget;
+  nsRefPtr<Accessible> mItem;
+  SelChangeType mSelChangeType;
+  uint32_t mPreceedingCount;
+  AccSelChangeEvent* mPackedEvent;
+
+  friend class EventQueue;
+};
+
+
+/**
+ * Accessible table change event.
+ */
+class AccTableChangeEvent : public AccEvent
+{
+public:
+  AccTableChangeEvent(Accessible* aAccessible, uint32_t aEventType,
+                      int32_t aRowOrColIndex, int32_t aNumRowsOrCols);
+
+  // AccEvent
+  static const EventGroup kEventGroup = eTableChangeEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eTableChangeEvent);
+  }
+
+  // AccTableChangeEvent
+  uint32_t GetIndex() const { return mRowOrColIndex; }
+  uint32_t GetCount() const { return mNumRowsOrCols; }
+
+private:
+  uint32_t mRowOrColIndex;   // the start row/column after which the rows are inserted/deleted.
+  uint32_t mNumRowsOrCols;   // the number of inserted/deleted rows/columns
+};
+
+/**
+ * Accessible virtual cursor change event.
+ */
+class AccVCChangeEvent : public AccEvent
+{
+public:
+  AccVCChangeEvent(Accessible* aAccessible,
+                   nsIAccessible* aOldAccessible,
+                   int32_t aOldStart, int32_t aOldEnd,
+                   int16_t aReason);
+
+  virtual ~AccVCChangeEvent() { }
+
+  // AccEvent
+  static const EventGroup kEventGroup = eVirtualCursorChangeEvent;
+  virtual unsigned int GetEventGroups() const
+  {
+    return AccEvent::GetEventGroups() | (1U << eVirtualCursorChangeEvent);
+  }
+
+  // AccTableChangeEvent
+  nsIAccessible* OldAccessible() const { return mOldAccessible; }
+  int32_t OldStartOffset() const { return mOldStart; }
+  int32_t OldEndOffset() const { return mOldEnd; }
+  int32_t Reason() const { return mReason; }
+
+private:
+  nsRefPtr<nsIAccessible> mOldAccessible;
+  int32_t mOldStart;
+  int32_t mOldEnd;
+  int16_t mReason;
+};
+
+/**
+ * Downcast the generic accessible event object to derived type.
+ */
+class downcast_accEvent
+{
+public:
+  downcast_accEvent(AccEvent* e) : mRawPtr(e) { }
+
+  template<class Destination>
+  operator Destination*() {
+    if (!mRawPtr)
+      return nullptr;
+
+    return mRawPtr->GetEventGroups() & (1U << Destination::kEventGroup) ?
+      static_cast<Destination*>(mRawPtr) : nullptr;
+  }
+
+private:
+  AccEvent* mRawPtr;
+};
+
+/**
+ * Return a new xpcom accessible event for the given internal one.
+ */
+already_AddRefed<nsIAccessibleEvent>
+MakeXPCEvent(AccEvent* aEvent);
+
+} // namespace a11y
+} // namespace mozilla
+
+#endif
+