summaryrefslogtreecommitdiffstats
path: root/accessible/generic/LocalAccessible.h
blob: 51c4cc94242ab5e53feec875771c3be2f4706514 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
/* -*- 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 _LocalAccessible_H_
#define _LocalAccessible_H_

#include "mozilla/ComputedStyle.h"
#include "mozilla/a11y/Accessible.h"
#include "mozilla/a11y/AccTypes.h"
#include "mozilla/a11y/RelationType.h"
#include "mozilla/a11y/States.h"

#include "mozilla/UniquePtr.h"

#include "nsIContent.h"
#include "nsTArray.h"
#include "nsRefPtrHashtable.h"
#include "nsRect.h"

struct nsRoleMapEntry;

class nsIFrame;

class nsAttrValue;

namespace mozilla::dom {
class Element;
}

namespace mozilla {
namespace a11y {

class LocalAccessible;
class AccAttributes;
class AccEvent;
class AccGroupInfo;
class ApplicationAccessible;
class CacheData;
class DocAccessible;
class EmbeddedObjCollector;
class EventTree;
class HTMLImageMapAccessible;
class HTMLLIAccessible;
class HTMLLinkAccessible;
class HyperTextAccessible;
class HyperTextAccessibleBase;
class ImageAccessible;
class KeyBinding;
class OuterDocAccessible;
class RemoteAccessible;
class Relation;
class RootAccessible;
class TableAccessible;
class TableCellAccessible;
class TextLeafAccessible;
class XULLabelAccessible;
class XULTreeAccessible;

enum class CacheUpdateType;

#ifdef A11Y_LOG
namespace logging {
typedef const char* (*GetTreePrefix)(void* aData, LocalAccessible*);
void Tree(const char* aTitle, const char* aMsgText, LocalAccessible* aRoot,
          GetTreePrefix aPrefixFunc, void* GetTreePrefixData);
void TreeSize(const char* aTitle, const char* aMsgText, LocalAccessible* aRoot);
};  // namespace logging
#endif

typedef nsRefPtrHashtable<nsPtrHashKey<const void>, LocalAccessible>
    AccessibleHashtable;

#define NS_ACCESSIBLE_IMPL_IID                       \
  { /* 133c8bf4-4913-4355-bd50-426bd1d6e1ad */       \
    0x133c8bf4, 0x4913, 0x4355, {                    \
      0xbd, 0x50, 0x42, 0x6b, 0xd1, 0xd6, 0xe1, 0xad \
    }                                                \
  }

/**
 * An accessibility tree node that originated in mDoc's content process.
 */
class LocalAccessible : public nsISupports, public Accessible {
 public:
  LocalAccessible(nsIContent* aContent, DocAccessible* aDoc);

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_CLASS(LocalAccessible)

  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ACCESSIBLE_IMPL_IID)

  //////////////////////////////////////////////////////////////////////////////
  // Public methods

  /**
   * Return the document accessible for this accessible.
   */
  DocAccessible* Document() const { return mDoc; }

  /**
   * Return the root document accessible for this accessible.
   */
  a11y::RootAccessible* RootAccessible() const;

  /**
   * Return frame for this accessible.
   * Note that this will return null for display: contents. Also,
   * DocAccessible::GetFrame can return null if the frame tree hasn't been
   * created yet.
   */
  virtual nsIFrame* GetFrame() const;

  /**
   * Return DOM node associated with the accessible.
   */
  virtual nsINode* GetNode() const;

  nsIContent* GetContent() const { return mContent; }
  dom::Element* Elm() const;

  /**
   * Return node type information of DOM node associated with the accessible.
   */
  bool IsContent() const { return GetNode() && GetNode()->IsContent(); }

  /**
   * Return the unique identifier of the accessible.
   * ID() should be preferred, but this method still exists because many
   * LocalAccessible callers expect a void*.
   */
  void* UniqueID() { return static_cast<void*>(this); }

  virtual uint64_t ID() const override {
    return IsDoc() ? 0 : reinterpret_cast<uintptr_t>(this);
  }

  virtual void Language(nsAString& aLocale) override;

  /**
   * Get the description of this accessible.
   */
  virtual void Description(nsString& aDescription) const override;

  /**
   * Get the value of this accessible.
   */
  virtual void Value(nsString& aValue) const override;

  /**
   * Get the name of this accessible.
   */
  virtual ENameValueFlag Name(nsString& aName) const override;

  /**
   * Maps ARIA state attributes to state of accessible. Note the given state
   * argument should hold states for accessible before you pass it into this
   * method.
   *
   * @param  [in/out] where to fill the states into.
   */
  virtual void ApplyARIAState(uint64_t* aState) const;

  /**
   * Return enumerated accessible role (see constants in Role.h).
   */
  virtual mozilla::a11y::role Role() const override;

  /**
   * Return accessible role specified by ARIA (see constants in
   * roles).
   */
  inline mozilla::a11y::role ARIARole();

  /**
   * Returns enumerated accessible role from native markup (see constants in
   * Role.h). Doesn't take into account ARIA roles.
   */
  virtual mozilla::a11y::role NativeRole() const;

  virtual uint64_t State() override;

  /**
   * Return interactive states present on the accessible
   * (@see NativeInteractiveState).
   */
  uint64_t InteractiveState() const {
    uint64_t state = NativeInteractiveState();
    ApplyARIAState(&state);
    return state;
  }

  /**
   * Return link states present on the accessible.
   */
  uint64_t LinkState() const {
    uint64_t state = NativeLinkState();
    ApplyARIAState(&state);
    return state;
  }

  /**
   * Return the states of accessible, not taking into account ARIA states.
   * Use State() to get complete set of states.
   */
  virtual uint64_t NativeState() const;

  /**
   * Return native interactice state (unavailable, focusable or selectable).
   */
  virtual uint64_t NativeInteractiveState() const;

  /**
   * Return native link states present on the accessible.
   */
  virtual uint64_t NativeLinkState() const;

  /**
   * Return bit set of invisible and offscreen states.
   */
  uint64_t VisibilityState() const;

  /**
   * Return true if native unavailable state present.
   */
  virtual bool NativelyUnavailable() const;

  virtual already_AddRefed<AccAttributes> Attributes() override;

  /**
   * Return direct or deepest child at the given point.
   *
   * @param  aX           [in] x coordinate relative screen
   * @param  aY           [in] y coordinate relative screen
   * @param  aWhichChild  [in] flag points if deepest or direct child
   *                        should be returned
   */
  virtual LocalAccessible* LocalChildAtPoint(int32_t aX, int32_t aY,
                                             EWhichChildAtPoint aWhichChild);

  /**
   * Similar to LocalChildAtPoint but crosses process boundaries.
   */
  virtual Accessible* ChildAtPoint(int32_t aX, int32_t aY,
                                   EWhichChildAtPoint aWhichChild) override;

  virtual Relation RelationByType(RelationType aType) const override;

  //////////////////////////////////////////////////////////////////////////////
  // Initializing methods

  /**
   * Shutdown this accessible object.
   */
  virtual void Shutdown();

  /**
   * Set the ARIA role map entry for a new accessible.
   */
  inline void SetRoleMapEntry(const nsRoleMapEntry* aRoleMapEntry);

  /**
   * Append/insert/remove a child. Return true if operation was successful.
   */
  bool AppendChild(LocalAccessible* aChild) {
    return InsertChildAt(mChildren.Length(), aChild);
  }
  virtual bool InsertChildAt(uint32_t aIndex, LocalAccessible* aChild);

  /**
   * Inserts a child after given sibling. If the child cannot be inserted,
   * then the child is unbound from the document, and false is returned. Make
   * sure to null out any references on the child object as it may be destroyed.
   */
  inline bool InsertAfter(LocalAccessible* aNewChild,
                          LocalAccessible* aRefChild);

  virtual bool RemoveChild(LocalAccessible* aChild);

  /**
   * Reallocates the child within its parent.
   */
  virtual void RelocateChild(uint32_t aNewIndex, LocalAccessible* aChild);

  // Accessible hierarchy method overrides

  virtual Accessible* Parent() const override { return LocalParent(); }

  virtual Accessible* ChildAt(uint32_t aIndex) const override {
    return LocalChildAt(aIndex);
  }

  virtual Accessible* NextSibling() const override {
    return LocalNextSibling();
  }

  virtual Accessible* PrevSibling() const override {
    return LocalPrevSibling();
  }

  //////////////////////////////////////////////////////////////////////////////
  // LocalAccessible tree traverse methods

  /**
   * Return parent accessible.
   */
  LocalAccessible* LocalParent() const { return mParent; }

  /**
   * Return child accessible at the given index.
   */
  virtual LocalAccessible* LocalChildAt(uint32_t aIndex) const;

  /**
   * Return child accessible count.
   */
  virtual uint32_t ChildCount() const override;

  /**
   * Return index of the given child accessible.
   */
  int32_t GetIndexOf(const LocalAccessible* aChild) const {
    return (aChild->mParent != this) ? -1 : aChild->IndexInParent();
  }

  /**
   * Return index in parent accessible.
   */
  virtual int32_t IndexInParent() const override;

  /**
   * Return first/last/next/previous sibling of the accessible.
   */
  inline LocalAccessible* LocalNextSibling() const {
    return GetSiblingAtOffset(1);
  }
  inline LocalAccessible* LocalPrevSibling() const {
    return GetSiblingAtOffset(-1);
  }
  inline LocalAccessible* LocalFirstChild() const { return LocalChildAt(0); }
  inline LocalAccessible* LocalLastChild() const {
    uint32_t childCount = ChildCount();
    return childCount != 0 ? LocalChildAt(childCount - 1) : nullptr;
  }

  virtual uint32_t EmbeddedChildCount() override;

  /**
   * Return embedded accessible child at the given index.
   */
  virtual Accessible* EmbeddedChildAt(uint32_t aIndex) override;

  virtual int32_t IndexOfEmbeddedChild(Accessible* aChild) override;

  /**
   * Return number of content children/content child at index. The content
   * child is created from markup in contrast to it's never constructed by its
   * parent accessible (like treeitem accessibles for XUL trees).
   */
  uint32_t ContentChildCount() const { return mChildren.Length(); }
  LocalAccessible* ContentChildAt(uint32_t aIndex) const {
    return mChildren.ElementAt(aIndex);
  }

  /**
   * Return true if the accessible is attached to tree.
   */
  bool IsBoundToParent() const { return !!mParent; }

  //////////////////////////////////////////////////////////////////////////////
  // Miscellaneous methods

  /**
   * Handle accessible event, i.e. process it, notifies observers and fires
   * platform specific event.
   */
  virtual nsresult HandleAccEvent(AccEvent* aAccEvent);

  /**
   * Return true if the accessible is an acceptable child.
   */
  virtual bool IsAcceptableChild(nsIContent* aEl) const {
    return aEl &&
           !aEl->IsAnyOfHTMLElements(nsGkAtoms::option, nsGkAtoms::optgroup);
  }

  virtual void AppendTextTo(nsAString& aText, uint32_t aStartOffset = 0,
                            uint32_t aLength = UINT32_MAX) override;

  virtual nsRect BoundsInAppUnits() const override;

  virtual LayoutDeviceIntRect Bounds() const override;

  /**
   * Return boundaries rect relative the bounding frame.
   */
  virtual nsRect RelativeBounds(nsIFrame** aRelativeFrame) const;

  /**
   * Return boundaries rect relative to the frame of the parent accessible.
   * The returned bounds are the same regardless of whether the parent is
   * scrolled. This means the scroll position must be later subtracted to
   * calculate absolute coordinates.
   */
  virtual nsRect ParentRelativeBounds();

  /**
   * Selects the accessible within its container if applicable.
   */
  virtual void SetSelected(bool aSelect) override;

  /**
   * Select the accessible within its container.
   */
  virtual void TakeSelection() override;

  /**
   * Focus the accessible.
   */
  MOZ_CAN_RUN_SCRIPT_BOUNDARY virtual void TakeFocus() const override;

  MOZ_CAN_RUN_SCRIPT
  virtual void ScrollTo(uint32_t aHow) const override;

  virtual void ScrollToPoint(uint32_t aCoordinateType, int32_t aX,
                             int32_t aY) override;

  /**
   * Get a pointer to accessibility interface for this node, which is specific
   * to the OS/accessibility toolkit we're running on.
   */
  virtual void GetNativeInterface(void** aNativeAccessible);

  virtual Maybe<int32_t> GetIntARIAAttr(nsAtom* aAttrName) const override;

  //////////////////////////////////////////////////////////////////////////////
  // Downcasting and types

  inline bool IsAbbreviation() const {
    return mContent &&
           mContent->IsAnyOfHTMLElements(nsGkAtoms::abbr, nsGkAtoms::acronym);
  }

  ApplicationAccessible* AsApplication();

  DocAccessible* AsDoc();

  HyperTextAccessible* AsHyperText();
  virtual HyperTextAccessibleBase* AsHyperTextBase() override;

  HTMLLIAccessible* AsHTMLListItem();

  HTMLLinkAccessible* AsHTMLLink();

  ImageAccessible* AsImage();

  HTMLImageMapAccessible* AsImageMap();

  OuterDocAccessible* AsOuterDoc();

  a11y::RootAccessible* AsRoot();

  virtual TableAccessible* AsTable() override;
  virtual TableCellAccessible* AsTableCell() override;

  TextLeafAccessible* AsTextLeaf();

  XULLabelAccessible* AsXULLabel();

  XULTreeAccessible* AsXULTree();

  //////////////////////////////////////////////////////////////////////////////
  // ActionAccessible

  virtual bool HasPrimaryAction() const override;

  virtual uint8_t ActionCount() const override;

  virtual void ActionNameAt(uint8_t aIndex, nsAString& aName) override;

  virtual bool DoAction(uint8_t aIndex) const override;

  virtual KeyBinding AccessKey() const override;

  /**
   * Return global keyboard shortcut for default action, such as Ctrl+O for
   * Open file menuitem.
   */
  virtual KeyBinding KeyboardShortcut() const;

  //////////////////////////////////////////////////////////////////////////////
  // HyperLinkAccessible (any embedded object in text can implement HyperLink,
  // which helps determine where it is located within containing text).

  /**
   * Return true if the accessible is hyper link accessible.
   */
  virtual bool IsLink() const override;

  //////////////////////////////////////////////////////////////////////////////
  // SelectAccessible

  /**
   * Return an array of selected items.
   */
  virtual void SelectedItems(nsTArray<Accessible*>* aItems) override;

  /**
   * Return the number of selected items.
   */
  virtual uint32_t SelectedItemCount() override;

  /**
   * Return selected item at the given index.
   */
  virtual Accessible* GetSelectedItem(uint32_t aIndex) override;

  /**
   * Determine if item at the given index is selected.
   */
  virtual bool IsItemSelected(uint32_t aIndex) override;

  /**
   * Add item at the given index the selection. Return true if success.
   */
  virtual bool AddItemToSelection(uint32_t aIndex) override;

  /**
   * Remove item at the given index from the selection. Return if success.
   */
  virtual bool RemoveItemFromSelection(uint32_t aIndex) override;

  /**
   * Select all items. Return true if success.
   */
  virtual bool SelectAll() override;

  /**
   * Unselect all items. Return true if success.
   */
  virtual bool UnselectAll() override;

  //////////////////////////////////////////////////////////////////////////////
  // Value (numeric value interface)

  virtual double MaxValue() const override;
  virtual double MinValue() const override;
  virtual double CurValue() const override;
  virtual double Step() const override;
  virtual bool SetCurValue(double aValue) override;

  //////////////////////////////////////////////////////////////////////////////
  // Widgets

  /**
   * Return true if accessible is a widget, i.e. control or accessible that
   * manages its items. Note, being a widget the accessible may be a part of
   * composite widget.
   */
  virtual bool IsWidget() const;

  /**
   * Return true if the widget is active, i.e. has a focus within it.
   */
  virtual bool IsActiveWidget() const;

  /**
   * Return true if the widget has items and items are operable by user and
   * can be activated.
   */
  virtual bool AreItemsOperable() const;

  /**
   * Return the current item of the widget, i.e. an item that has or will have
   * keyboard focus when widget gets active.
   */
  virtual LocalAccessible* CurrentItem() const;

  /**
   * Set the current item of the widget.
   */
  virtual void SetCurrentItem(const LocalAccessible* aItem);

  /**
   * Return container widget this accessible belongs to.
   */
  virtual LocalAccessible* ContainerWidget() const;

  /**
   * Accessible's element ID is referenced as a aria-activedescendant in the
   * document. This method is only used for ID changes and therefore does not
   * need to work for direct element references via ariaActiveDescendantElement.
   */
  bool IsActiveDescendantId(LocalAccessible** aWidget = nullptr) const;

  /**
   * Return true if the accessible is defunct.
   */
  inline bool IsDefunct() const;

  /**
   * Return false if the accessible is no longer in the document.
   */
  bool IsInDocument() const { return !(mStateFlags & eIsNotInDocument); }

  /**
   * Return true if the accessible should be contained by document node map.
   */
  bool IsNodeMapEntry() const {
    return HasOwnContent() && !(mStateFlags & eNotNodeMapEntry);
  }

  /**
   * Return true if the accessible has associated DOM content.
   */
  bool HasOwnContent() const {
    return mContent && !(mStateFlags & eSharedNode);
  }

  /**
   * Return true if native markup has a numeric value.
   */
  inline bool NativeHasNumericValue() const;

  /**
   * Return true if ARIA specifies support for a numeric value.
   */
  inline bool ARIAHasNumericValue() const;

  /**
   * Return true if the accessible has a numeric value.
   */
  virtual bool HasNumericValue() const override;

  /**
   * Return true if the accessible state change is processed by handling proper
   * DOM UI event, if otherwise then false. For example, CheckboxAccessible
   * created for HTML:input@type="checkbox" will process
   * nsIDocumentObserver::ElementStateChanged instead of 'CheckboxStateChange'
   * event.
   */
  bool NeedsDOMUIEvent() const { return !(mStateFlags & eIgnoreDOMUIEvent); }

  /**
   * Get/set repositioned bit indicating that the accessible was moved in
   * the accessible tree, i.e. the accessible tree structure differs from DOM.
   */
  bool IsRelocated() const { return mStateFlags & eRelocated; }
  void SetRelocated(bool aRelocated) {
    if (aRelocated) {
      mStateFlags |= eRelocated;
    } else {
      mStateFlags &= ~eRelocated;
    }
  }

  /**
   * Return true if the accessible allows accessible children from subtree of
   * a DOM element of this accessible.
   */
  bool KidsFromDOM() const { return !(mStateFlags & eNoKidsFromDOM); }

  /**
   * Return true if this accessible has a parent, relation or ancestor with a
   * relation whose name depends on this accessible.
   */
  bool HasNameDependent() const { return mContextFlags & eHasNameDependent; }

  /**
   * Return true if this accessible has a parent, relation or ancestor with a
   * relation whose description depends on this accessible.
   */
  bool HasDescriptionDependent() const {
    return mContextFlags & eHasDescriptionDependent;
  }

  /**
   * Return true if the element is inside an alert.
   */
  bool IsInsideAlert() const { return mContextFlags & eInsideAlert; }

  /**
   * Return true if there is a pending reorder event for this accessible.
   */
  bool ReorderEventTarget() const { return mReorderEventTarget; }

  /**
   * Return true if there is a pending show event for this accessible.
   */
  bool ShowEventTarget() const { return mShowEventTarget; }

  /**
   * Return true if there is a pending hide event for this accessible.
   */
  bool HideEventTarget() const { return mHideEventTarget; }

  /**
   * Set if there is a pending reorder event for this accessible.
   */
  void SetReorderEventTarget(bool aTarget) { mReorderEventTarget = aTarget; }

  /**
   * Set if this accessible is a show event target.
   */
  void SetShowEventTarget(bool aTarget) { mShowEventTarget = aTarget; }

  /**
   * Set if this accessible is a hide event target.
   */
  void SetHideEventTarget(bool aTarget) { mHideEventTarget = aTarget; }

  void Announce(const nsAString& aAnnouncement, uint16_t aPriority);

  virtual bool IsRemote() const override { return false; }

  already_AddRefed<AccAttributes> BundleFieldsForCache(
      uint64_t aCacheDomain, CacheUpdateType aUpdateType);

  /**
   * Push fields to cache.
   * aCacheDomain - describes which fields to bundle and ultimately send
   * aUpdate - describes whether this is an initial or subsequent update
   */
  void SendCache(uint64_t aCacheDomain, CacheUpdateType aUpdate);

  void MaybeQueueCacheUpdateForStyleChanges();

  virtual nsAtom* TagName() const override;

  virtual already_AddRefed<nsAtom> InputType() const override;

  virtual already_AddRefed<nsAtom> DisplayStyle() const override;

  virtual float Opacity() const override;

  virtual void DOMNodeID(nsString& aID) const override;

  virtual void LiveRegionAttributes(nsAString* aLive, nsAString* aRelevant,
                                    Maybe<bool>* aAtomic,
                                    nsAString* aBusy) const override;

  virtual Maybe<bool> ARIASelected() const override;

 protected:
  virtual ~LocalAccessible();

  /**
   * Return the accessible name provided by native markup. It doesn't take
   * into account ARIA markup used to specify the name.
   */
  virtual mozilla::a11y::ENameValueFlag NativeName(nsString& aName) const;

  /**
   * Return the accessible description provided by native markup. It doesn't
   * take into account ARIA markup used to specify the description.
   */
  void NativeDescription(nsString& aDescription) const;

  /**
   * Return object attributes provided by native markup. It doesn't take into
   * account ARIA.
   */
  virtual already_AddRefed<AccAttributes> NativeAttributes();

  /**
   * The given attribute has the potential of changing the accessible's state.
   * This is used to capture the state before the attribute change and compare
   * it with the state after.
   */
  virtual bool AttributeChangesState(nsAtom* aAttribute);

  /**
   * Notify accessible that a DOM attribute on its associated content has
   * changed. This allows the accessible to update its state and emit any
   * relevant events.
   */
  virtual void DOMAttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute,
                                   int32_t aModType,
                                   const nsAttrValue* aOldValue,
                                   uint64_t aOldState);

  //////////////////////////////////////////////////////////////////////////////
  // Initializing, cache and tree traverse methods

  /**
   * Destroy the object.
   */
  void LastRelease();

  /**
   * Set accessible parent and index in parent.
   */
  void BindToParent(LocalAccessible* aParent, uint32_t aIndexInParent);
  void UnbindFromParent();

  /**
   * Return sibling accessible at the given offset.
   */
  virtual LocalAccessible* GetSiblingAtOffset(int32_t aOffset,
                                              nsresult* aError = nullptr) const;

  void ModifySubtreeContextFlags(uint32_t aContextFlags, bool aAdd);

  /**
   * Flags used to describe the state of this accessible.
   */
  enum StateFlags {
    eIsDefunct = 1 << 0,        // accessible is defunct
    eIsNotInDocument = 1 << 1,  // accessible is not in document
    eSharedNode = 1 << 2,  // accessible shares DOM node from another accessible
    eNotNodeMapEntry = 1 << 3,   // accessible shouldn't be in document node map
    eGroupInfoDirty = 1 << 4,    // accessible needs to update group info
    eKidsMutating = 1 << 5,      // subtree is being mutated
    eIgnoreDOMUIEvent = 1 << 6,  // don't process DOM UI events for a11y events
    eRelocated = 1 << 7,         // accessible was moved in tree
    eNoKidsFromDOM = 1 << 8,     // accessible doesn't allow children from DOM
    eHasTextKids = 1 << 9,       // accessible have a text leaf in children
    eOldFrameHasValidTransformStyle =
        1 << 10,  // frame prior to most recent style change both has transform
                  // styling and supports transforms

    eLastStateFlag = eOldFrameHasValidTransformStyle
  };

  /**
   * Flags used for contextual information about the accessible.
   */
  enum ContextFlags {
    eHasNameDependent = 1 << 0,  // See HasNameDependent().
    eInsideAlert = 1 << 1,
    eHasDescriptionDependent = 1 << 2,  // See HasDescriptionDependent().

    eLastContextFlag = eHasDescriptionDependent
  };

 protected:
  //////////////////////////////////////////////////////////////////////////////
  // Miscellaneous helpers

  /**
   * Return ARIA role (helper method).
   */
  mozilla::a11y::role ARIATransformRole(mozilla::a11y::role aRole) const;

  /**
   * Return the minimum role that should be used as a last resort if the element
   * does not have a more specific role.
   */
  mozilla::a11y::role GetMinimumRole(mozilla::a11y::role aRole) const;

  //////////////////////////////////////////////////////////////////////////////
  // Name helpers

  /**
   * Returns the accessible name specified by ARIA.
   */
  void ARIAName(nsString& aName) const;

  /**
   * Returns the accessible description specified by ARIA.
   */
  void ARIADescription(nsString& aDescription) const;

  /**
   * Returns the accessible name specified for this control using XUL
   * <label control="id" ...>.
   */
  static void NameFromAssociatedXULLabel(DocAccessible* aDocument,
                                         nsIContent* aElm, nsString& aName);

  /**
   * Return the name for XUL element.
   */
  static void XULElmName(DocAccessible* aDocument, nsIContent* aElm,
                         nsString& aName);

  // helper method to verify frames
  static nsresult GetFullKeyName(const nsAString& aModifierName,
                                 const nsAString& aKeyName,
                                 nsAString& aStringOut);

  //////////////////////////////////////////////////////////////////////////////
  // Action helpers

  /**
   * Prepares click action that will be invoked in timeout.
   *
   * @note  DoCommand() prepares an action in timeout because when action
   *  command opens a modal dialog/window, it won't return until the
   *  dialog/window is closed. If executing action command directly in
   *  nsIAccessible::DoAction() method, it will block AT tools (e.g. GOK) that
   *  invoke action of mozilla accessibles direclty (see bug 277888 for
   * details).
   *
   * @param  aContent      [in, optional] element to click
   * @param  aActionIndex  [in, optional] index of accessible action
   */
  void DoCommand(nsIContent* aContent = nullptr,
                 uint32_t aActionIndex = 0) const;

  /**
   * Dispatch click event.
   */
  MOZ_CAN_RUN_SCRIPT
  virtual void DispatchClickEvent(nsIContent* aContent,
                                  uint32_t aActionIndex) const;

  //////////////////////////////////////////////////////////////////////////////
  // Helpers

  /**
   *  Get the container node for an atomic region, defined by aria-atomic="true"
   *  @return the container node
   */
  nsIContent* GetAtomicRegion() const;

  /**
   * Return numeric value of the given ARIA attribute, NaN if not applicable.
   *
   * @param aARIAProperty  [in] the ARIA property we're using
   * @return  a numeric value
   */
  double AttrNumericValue(nsAtom* aARIAAttr) const;

  /**
   * Return the action rule based on ARIA enum constants EActionRule
   * (see ARIAMap.h). Used by ActionCount() and ActionNameAt().
   */
  uint32_t GetActionRule() const;

  virtual AccGroupInfo* GetGroupInfo() const override;

  virtual AccGroupInfo* GetOrCreateGroupInfo() override;

  virtual void ARIAGroupPosition(int32_t* aLevel, int32_t* aSetSize,
                                 int32_t* aPosInSet) const override;

  // Data Members
  // mContent can be null in a DocAccessible if the document has no body or
  // root element, or if the initial tree hasn't been constructed yet.
  nsCOMPtr<nsIContent> mContent;
  RefPtr<DocAccessible> mDoc;

  LocalAccessible* mParent;
  nsTArray<LocalAccessible*> mChildren;
  int32_t mIndexInParent;

  // These are used to determine whether to send cache updates.
  Maybe<nsRect> mBounds;
  int32_t mFirstLineStart;

  /**
   * Maintain a reference to the ComputedStyle of our frame so we can
   * send cache updates when style changes are observed.
   *
   * This RefPtr is initialised in BundleFieldsForCache to the ComputedStyle
   * for our initial frame.
   * Style changes are observed in one of two ways:
   * 1. Style changes on the same frame are observed in
   * nsIFrame::DidSetComputedStyle.
   * 2. Style changes for reconstructed frames are handled in
   * DocAccessible::PruneOrInsertSubtree.
   * In both cases, we call into MaybeQueueCacheUpdateForStyleChanges. There, we
   * compare a11y-relevant properties in mOldComputedStyle with the current
   * ComputedStyle fetched from GetFrame()->Style(). Finally, we send cache
   * updates for attributes affected by the style change and update
   * mOldComputedStyle to the style of our current frame.
   */
  RefPtr<const ComputedStyle> mOldComputedStyle;

  static const uint8_t kStateFlagsBits = 11;
  static const uint8_t kContextFlagsBits = 3;

  /**
   * Keep in sync with StateFlags, ContextFlags, and AccTypes.
   */
  mutable uint32_t mStateFlags : kStateFlagsBits;
  uint32_t mContextFlags : kContextFlagsBits;
  uint32_t mReorderEventTarget : 1;
  uint32_t mShowEventTarget : 1;
  uint32_t mHideEventTarget : 1;

  void StaticAsserts() const;

#ifdef A11Y_LOG
  friend void logging::Tree(const char* aTitle, const char* aMsgText,
                            LocalAccessible* aRoot,
                            logging::GetTreePrefix aPrefixFunc,
                            void* aGetTreePrefixData);
  friend void logging::TreeSize(const char* aTitle, const char* aMsgText,
                                LocalAccessible* aRoot);
#endif
  friend class DocAccessible;
  friend class xpcAccessible;
  friend class TreeMutation;

  UniquePtr<mozilla::a11y::EmbeddedObjCollector> mEmbeddedObjCollector;
  int32_t mIndexOfEmbeddedChild;

  friend class EmbeddedObjCollector;

  mutable AccGroupInfo* mGroupInfo;
  friend class AccGroupInfo;

 private:
  LocalAccessible() = delete;
  LocalAccessible(const LocalAccessible&) = delete;
  LocalAccessible& operator=(const LocalAccessible&) = delete;

  /**
   * Traverses the accessible's parent chain in search of an accessible with
   * a frame. Returns the frame when found. Includes special handling for
   * OOP iframe docs and tab documents.
   */
  nsIFrame* FindNearestAccessibleAncestorFrame();

  /*
   * This function assumes that the current role is not valid. It searches for a
   * fallback role in the role attribute string, and returns it. If there is no
   * valid fallback role in the role attribute string, the function returns the
   * native role. The aRolesToSkip parameter will cause the function to skip any
   * roles found in the role attribute string when searching for the next valid
   * role.
   */
  role FindNextValidARIARole(
      std::initializer_list<nsStaticAtom*> aRolesToSkip) const;

  LocalAccessible* GetPopoverTargetDetailsRelation() const;
};

NS_DEFINE_STATIC_IID_ACCESSOR(LocalAccessible, NS_ACCESSIBLE_IMPL_IID)

////////////////////////////////////////////////////////////////////////////////
// LocalAccessible downcasting method

inline LocalAccessible* Accessible::AsLocal() {
  return IsLocal() ? static_cast<LocalAccessible*>(this) : nullptr;
}

}  // namespace a11y
}  // namespace mozilla

#endif