1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "ui/views/accessibility/native_view_accessibility_win.h"
6
7#include <oleacc.h>
8#include <UIAutomationClient.h>
9
10#include <set>
11#include <vector>
12
13#include "base/memory/singleton.h"
14#include "base/strings/utf_string_conversions.h"
15#include "base/win/scoped_comptr.h"
16#include "base/win/windows_version.h"
17#include "third_party/iaccessible2/ia2_api_all.h"
18#include "ui/accessibility/ax_enums.h"
19#include "ui/accessibility/ax_text_utils.h"
20#include "ui/accessibility/ax_view_state.h"
21#include "ui/base/win/accessibility_ids_win.h"
22#include "ui/base/win/accessibility_misc_utils.h"
23#include "ui/base/win/atl_module.h"
24#include "ui/views/controls/button/custom_button.h"
25#include "ui/views/focus/focus_manager.h"
26#include "ui/views/focus/view_storage.h"
27#include "ui/views/widget/widget.h"
28#include "ui/views/win/hwnd_util.h"
29
30namespace views {
31namespace {
32
33class AccessibleWebViewRegistry {
34 public:
35  static AccessibleWebViewRegistry* GetInstance();
36
37  void RegisterWebView(View* web_view);
38
39  void UnregisterWebView(View* web_view);
40
41  // Given the view that received the request for the accessible
42  // id in |top_view|, and the child id requested, return the native
43  // accessible object with that child id from one of the WebViews in
44  // |top_view|'s view hierarchy, if any.
45  IAccessible* GetAccessibleFromWebView(View* top_view, long child_id);
46
47  // The system uses IAccessible APIs for many purposes, but only
48  // assistive technology like screen readers uses IAccessible2.
49  // Call this method to note that the IAccessible2 interface was queried and
50  // that WebViews should be proactively notified that this interface will be
51  // used. If this is enabled for the first time, this will explicitly call
52  // QueryService with an argument of IAccessible2 on all WebViews, otherwise
53  // it will just do it from now on.
54  void EnableIAccessible2Support();
55
56 private:
57  friend struct DefaultSingletonTraits<AccessibleWebViewRegistry>;
58  AccessibleWebViewRegistry();
59  ~AccessibleWebViewRegistry() {}
60
61  IAccessible* AccessibleObjectFromChildId(View* web_view, long child_id);
62
63  void QueryIAccessible2Interface(View* web_view);
64
65  // Set of all web views. We check whether each one is contained in a
66  // top view dynamically rather than keeping track of a map.
67  std::set<View*> web_views_;
68
69  // The most recent top view used in a call to GetAccessibleFromWebView.
70  View* last_top_view_;
71
72  // The most recent web view where an accessible object was found,
73  // corresponding to |last_top_view_|.
74  View* last_web_view_;
75
76  // If IAccessible2 support is enabled, we query the IAccessible2 interface
77  // of WebViews proactively when they're registered, so that they are
78  // aware that they need to support this interface.
79  bool iaccessible2_support_enabled_;
80
81  DISALLOW_COPY_AND_ASSIGN(AccessibleWebViewRegistry);
82};
83
84AccessibleWebViewRegistry::AccessibleWebViewRegistry()
85    : last_top_view_(NULL),
86      last_web_view_(NULL),
87      iaccessible2_support_enabled_(false) {
88}
89
90AccessibleWebViewRegistry* AccessibleWebViewRegistry::GetInstance() {
91  return Singleton<AccessibleWebViewRegistry>::get();
92}
93
94void AccessibleWebViewRegistry::RegisterWebView(View* web_view) {
95  DCHECK(web_views_.find(web_view) == web_views_.end());
96  web_views_.insert(web_view);
97
98  if (iaccessible2_support_enabled_)
99    QueryIAccessible2Interface(web_view);
100}
101
102void AccessibleWebViewRegistry::UnregisterWebView(View* web_view) {
103  DCHECK(web_views_.find(web_view) != web_views_.end());
104  web_views_.erase(web_view);
105  if (last_web_view_ == web_view) {
106    last_top_view_ = NULL;
107    last_web_view_ = NULL;
108  }
109}
110
111IAccessible* AccessibleWebViewRegistry::GetAccessibleFromWebView(
112    View* top_view, long child_id) {
113  // This function gets called frequently, so try to avoid searching all
114  // of the web views if the notification is on the same web view that
115  // sent the last one.
116  if (last_top_view_ == top_view) {
117    IAccessible* accessible =
118        AccessibleObjectFromChildId(last_web_view_, child_id);
119    if (accessible)
120      return accessible;
121  }
122
123  // Search all web views. For each one, first ensure it's a descendant
124  // of this view where the event was posted - and if so, see if it owns
125  // an accessible object with that child id. If so, save the view to speed
126  // up the next notification.
127  for (std::set<View*>::iterator iter = web_views_.begin();
128       iter != web_views_.end(); ++iter) {
129    View* web_view = *iter;
130    if (top_view == web_view || !top_view->Contains(web_view))
131      continue;
132    IAccessible* accessible = AccessibleObjectFromChildId(web_view, child_id);
133    if (accessible) {
134      last_top_view_ = top_view;
135      last_web_view_ = web_view;
136      return accessible;
137    }
138  }
139
140  return NULL;
141}
142
143void AccessibleWebViewRegistry::EnableIAccessible2Support() {
144  if (iaccessible2_support_enabled_)
145    return;
146  iaccessible2_support_enabled_ = true;
147  for (std::set<View*>::iterator iter = web_views_.begin();
148       iter != web_views_.end(); ++iter) {
149    QueryIAccessible2Interface(*iter);
150  }
151}
152
153IAccessible* AccessibleWebViewRegistry::AccessibleObjectFromChildId(
154    View* web_view,
155    long child_id) {
156  IAccessible* web_view_accessible = web_view->GetNativeViewAccessible();
157  if (web_view_accessible == NULL)
158    return NULL;
159
160  VARIANT var_child;
161  var_child.vt = VT_I4;
162  var_child.lVal = child_id;
163  IAccessible* result = NULL;
164  if (S_OK == web_view_accessible->get_accChild(
165      var_child, reinterpret_cast<IDispatch**>(&result))) {
166    return result;
167  }
168
169  return NULL;
170}
171
172void AccessibleWebViewRegistry::QueryIAccessible2Interface(View* web_view) {
173  IAccessible* web_view_accessible = web_view->GetNativeViewAccessible();
174  if (!web_view_accessible)
175    return;
176
177  base::win::ScopedComPtr<IServiceProvider> service_provider;
178  if (S_OK != web_view_accessible->QueryInterface(service_provider.Receive()))
179    return;
180  base::win::ScopedComPtr<IAccessible2> iaccessible2;
181  service_provider->QueryService(
182      IID_IAccessible, IID_IAccessible2,
183      reinterpret_cast<void**>(iaccessible2.Receive()));
184}
185
186}  // anonymous namespace
187
188// static
189long NativeViewAccessibilityWin::next_unique_id_ = 1;
190int NativeViewAccessibilityWin::view_storage_ids_[kMaxViewStorageIds] = {0};
191int NativeViewAccessibilityWin::next_view_storage_id_index_ = 0;
192std::vector<int> NativeViewAccessibilityWin::alert_target_view_storage_ids_;
193
194// static
195NativeViewAccessibility* NativeViewAccessibility::Create(View* view) {
196  // Make sure ATL is initialized in this module.
197  ui::win::CreateATLModuleIfNeeded();
198
199  CComObject<NativeViewAccessibilityWin>* instance = NULL;
200  HRESULT hr = CComObject<NativeViewAccessibilityWin>::CreateInstance(
201      &instance);
202  DCHECK(SUCCEEDED(hr));
203  instance->set_view(view);
204  instance->AddRef();
205  return instance;
206}
207
208NativeViewAccessibilityWin::NativeViewAccessibilityWin()
209    : unique_id_(next_unique_id_++) {
210}
211
212NativeViewAccessibilityWin::~NativeViewAccessibilityWin() {
213  RemoveAlertTarget();
214}
215
216void NativeViewAccessibilityWin::NotifyAccessibilityEvent(
217    ui::AXEvent event_type) {
218  if (!view_)
219    return;
220
221  ViewStorage* view_storage = ViewStorage::GetInstance();
222  HWND hwnd = HWNDForView(view_);
223  int view_storage_id = view_storage_ids_[next_view_storage_id_index_];
224  if (view_storage_id == 0) {
225    view_storage_id = view_storage->CreateStorageID();
226    view_storage_ids_[next_view_storage_id_index_] = view_storage_id;
227  } else {
228    view_storage->RemoveView(view_storage_id);
229  }
230  view_storage->StoreView(view_storage_id, view_);
231
232  // Positive child ids are used for enumerating direct children,
233  // negative child ids can be used as unique ids to refer to a specific
234  // descendants.  Make index into view_storage_ids_ into a negative child id.
235  int child_id =
236      base::win::kFirstViewsAccessibilityId - next_view_storage_id_index_;
237  ::NotifyWinEvent(MSAAEvent(event_type), hwnd, OBJID_CLIENT, child_id);
238  next_view_storage_id_index_ =
239      (next_view_storage_id_index_ + 1) % kMaxViewStorageIds;
240
241  // Keep track of views that are a target of an alert event.
242  if (event_type == ui::AX_EVENT_ALERT)
243    AddAlertTarget();
244}
245
246gfx::NativeViewAccessible NativeViewAccessibilityWin::GetNativeObject() {
247  return this;
248}
249
250void NativeViewAccessibilityWin::Destroy() {
251  view_ = NULL;
252  Release();
253}
254
255STDMETHODIMP NativeViewAccessibilityWin::accHitTest(
256    LONG x_left, LONG y_top, VARIANT* child) {
257  if (!child)
258    return E_INVALIDARG;
259
260  if (!view_ || !view_->GetWidget())
261    return E_FAIL;
262
263  // If this is a root view, our widget might have child widgets.
264  // Search child widgets first, since they're on top in the z-order.
265  if (view_->GetWidget()->GetRootView() == view_) {
266    std::vector<Widget*> child_widgets;
267    PopulateChildWidgetVector(&child_widgets);
268    for (size_t i = 0; i < child_widgets.size(); ++i) {
269      Widget* child_widget = child_widgets[i];
270      IAccessible* child_accessible =
271          child_widget->GetRootView()->GetNativeViewAccessible();
272      HRESULT result = child_accessible->accHitTest(x_left, y_top, child);
273      if (result == S_OK)
274        return result;
275    }
276  }
277
278  gfx::Point point(x_left, y_top);
279  View::ConvertPointFromScreen(view_, &point);
280
281  // If the point is not inside this view, return false.
282  if (!view_->HitTestPoint(point)) {
283    child->vt = VT_EMPTY;
284    return S_FALSE;
285  }
286
287  // Check if the point is within any of the immediate children of this
288  // view.
289  View* hit_child_view = NULL;
290  for (int i = view_->child_count() - 1; i >= 0; --i) {
291    View* child_view = view_->child_at(i);
292    if (!child_view->visible())
293      continue;
294
295    gfx::Point point_in_child_coords(point);
296    view_->ConvertPointToTarget(view_, child_view, &point_in_child_coords);
297    if (child_view->HitTestPoint(point_in_child_coords)) {
298      hit_child_view = child_view;
299      break;
300    }
301  }
302
303  // If the point was within one of this view's immediate children,
304  // call accHitTest recursively on that child's native view accessible -
305  // which may be a recursive call to this function or it may be overridden,
306  // for example in the case of a WebView.
307  if (hit_child_view) {
308    HRESULT result = hit_child_view->GetNativeViewAccessible()->accHitTest(
309        x_left, y_top, child);
310
311    // If the recursive call returned CHILDID_SELF, we have to convert that
312    // into a VT_DISPATCH for the return value to this call.
313    if (S_OK == result && child->vt == VT_I4 && child->lVal == CHILDID_SELF) {
314      child->vt = VT_DISPATCH;
315      child->pdispVal = hit_child_view->GetNativeViewAccessible();
316      // Always increment ref when returning a reference to a COM object.
317      child->pdispVal->AddRef();
318    }
319    return result;
320  }
321
322  // This object is the best match, so return CHILDID_SELF. It's tempting to
323  // simplify the logic and use VT_DISPATCH everywhere, but the Windows
324  // call AccessibleObjectFromPoint will keep calling accHitTest until some
325  // object returns CHILDID_SELF.
326  child->vt = VT_I4;
327  child->lVal = CHILDID_SELF;
328  return S_OK;
329}
330
331HRESULT NativeViewAccessibilityWin::accDoDefaultAction(VARIANT var_id) {
332  if (!IsValidId(var_id))
333    return E_INVALIDARG;
334
335  // The object does not support the method. This value is returned for
336  // controls that do not perform actions, such as edit fields.
337  return DISP_E_MEMBERNOTFOUND;
338}
339
340STDMETHODIMP NativeViewAccessibilityWin::accLocation(
341    LONG* x_left, LONG* y_top, LONG* width, LONG* height, VARIANT var_id) {
342  if (!IsValidId(var_id) || !x_left || !y_top || !width || !height)
343    return E_INVALIDARG;
344
345  if (!view_)
346    return E_FAIL;
347
348  if (!view_->bounds().IsEmpty()) {
349    *width  = view_->width();
350    *height = view_->height();
351    gfx::Point topleft(view_->bounds().origin());
352    View::ConvertPointToScreen(
353        view_->parent() ? view_->parent() : view_, &topleft);
354    *x_left = topleft.x();
355    *y_top  = topleft.y();
356  } else {
357    return E_FAIL;
358  }
359  return S_OK;
360}
361
362STDMETHODIMP NativeViewAccessibilityWin::accNavigate(
363    LONG nav_dir, VARIANT start, VARIANT* end) {
364  if (start.vt != VT_I4 || !end)
365    return E_INVALIDARG;
366
367  if (!view_)
368    return E_FAIL;
369
370  switch (nav_dir) {
371    case NAVDIR_FIRSTCHILD:
372    case NAVDIR_LASTCHILD: {
373      if (start.lVal != CHILDID_SELF) {
374        // Start of navigation must be on the View itself.
375        return E_INVALIDARG;
376      } else if (!view_->has_children()) {
377        // No children found.
378        return S_FALSE;
379      }
380
381      // Set child_id based on first or last child.
382      int child_id = 0;
383      if (nav_dir == NAVDIR_LASTCHILD)
384        child_id = view_->child_count() - 1;
385
386      View* child = view_->child_at(child_id);
387      end->vt = VT_DISPATCH;
388      end->pdispVal = child->GetNativeViewAccessible();
389      end->pdispVal->AddRef();
390      return S_OK;
391    }
392    case NAVDIR_LEFT:
393    case NAVDIR_UP:
394    case NAVDIR_PREVIOUS:
395    case NAVDIR_RIGHT:
396    case NAVDIR_DOWN:
397    case NAVDIR_NEXT: {
398      // Retrieve parent to access view index and perform bounds checking.
399      View* parent = view_->parent();
400      if (!parent) {
401        return E_FAIL;
402      }
403
404      if (start.lVal == CHILDID_SELF) {
405        int view_index = parent->GetIndexOf(view_);
406        // Check navigation bounds, adjusting for View child indexing (MSAA
407        // child indexing starts with 1, whereas View indexing starts with 0).
408        if (!IsValidNav(nav_dir, view_index, -1,
409                        parent->child_count() - 1)) {
410          // Navigation attempted to go out-of-bounds.
411          end->vt = VT_EMPTY;
412          return S_FALSE;
413        } else {
414          if (IsNavDirNext(nav_dir)) {
415            view_index += 1;
416          } else {
417            view_index -=1;
418          }
419        }
420
421        View* child = parent->child_at(view_index);
422        end->pdispVal = child->GetNativeViewAccessible();
423        end->vt = VT_DISPATCH;
424        end->pdispVal->AddRef();
425        return S_OK;
426      } else {
427        // Check navigation bounds, adjusting for MSAA child indexing (MSAA
428        // child indexing starts with 1, whereas View indexing starts with 0).
429        if (!IsValidNav(nav_dir, start.lVal, 0, parent->child_count() + 1)) {
430            // Navigation attempted to go out-of-bounds.
431            end->vt = VT_EMPTY;
432            return S_FALSE;
433          } else {
434            if (IsNavDirNext(nav_dir)) {
435              start.lVal += 1;
436            } else {
437              start.lVal -= 1;
438            }
439        }
440
441        HRESULT result = this->get_accChild(start, &end->pdispVal);
442        if (result == S_FALSE) {
443          // Child is a leaf.
444          end->vt = VT_I4;
445          end->lVal = start.lVal;
446        } else if (result == E_INVALIDARG) {
447          return E_INVALIDARG;
448        } else {
449          // Child is not a leaf.
450          end->vt = VT_DISPATCH;
451        }
452      }
453      break;
454    }
455    default:
456      return E_INVALIDARG;
457  }
458  // Navigation performed correctly. Global return for this function, if no
459  // error triggered an escape earlier.
460  return S_OK;
461}
462
463STDMETHODIMP NativeViewAccessibilityWin::get_accChild(VARIANT var_child,
464                                                      IDispatch** disp_child) {
465  if (var_child.vt != VT_I4 || !disp_child)
466    return E_INVALIDARG;
467
468  if (!view_ || !view_->GetWidget())
469    return E_FAIL;
470
471  LONG child_id = V_I4(&var_child);
472
473  if (child_id == CHILDID_SELF) {
474    // Remain with the same dispatch.
475    return S_OK;
476  }
477
478  // If this is a root view, our widget might have child widgets. Include
479  std::vector<Widget*> child_widgets;
480  if (view_->GetWidget()->GetRootView() == view_)
481    PopulateChildWidgetVector(&child_widgets);
482  int child_widget_count = static_cast<int>(child_widgets.size());
483
484  View* child_view = NULL;
485  if (child_id > 0) {
486    // Positive child ids are a 1-based child index, used by clients
487    // that want to enumerate all immediate children.
488    int child_id_as_index = child_id - 1;
489    if (child_id_as_index < view_->child_count()) {
490      child_view = view_->child_at(child_id_as_index);
491    } else if (child_id_as_index < view_->child_count() + child_widget_count) {
492      Widget* child_widget =
493          child_widgets[child_id_as_index - view_->child_count()];
494      child_view = child_widget->GetRootView();
495    }
496  } else {
497    // Negative child ids can be used to map to any descendant.
498    // Check child widget first.
499    for (int i = 0; i < child_widget_count; i++) {
500      Widget* child_widget = child_widgets[i];
501      IAccessible* child_accessible =
502          child_widget->GetRootView()->GetNativeViewAccessible();
503      HRESULT result = child_accessible->get_accChild(var_child, disp_child);
504      if (result == S_OK)
505        return result;
506    }
507
508    // We map child ids to a view storage id that can refer to a
509    // specific view (if that view still exists).
510    int view_storage_id_index =
511        base::win::kFirstViewsAccessibilityId - child_id;
512    if (view_storage_id_index >= 0 &&
513        view_storage_id_index < kMaxViewStorageIds) {
514      int view_storage_id = view_storage_ids_[view_storage_id_index];
515      ViewStorage* view_storage = ViewStorage::GetInstance();
516      child_view = view_storage->RetrieveView(view_storage_id);
517    } else {
518      *disp_child = AccessibleWebViewRegistry::GetInstance()->
519          GetAccessibleFromWebView(view_, child_id);
520      if (*disp_child)
521        return S_OK;
522    }
523  }
524
525  if (!child_view) {
526    // No child found.
527    *disp_child = NULL;
528    return E_FAIL;
529  }
530
531  *disp_child = child_view->GetNativeViewAccessible();
532  if (*disp_child) {
533    (*disp_child)->AddRef();
534    return S_OK;
535  }
536
537  return E_FAIL;
538}
539
540STDMETHODIMP NativeViewAccessibilityWin::get_accChildCount(LONG* child_count) {
541  if (!child_count)
542    return E_INVALIDARG;
543
544  if (!view_ || !view_->GetWidget())
545    return E_FAIL;
546
547  *child_count = view_->child_count();
548
549  // If this is a root view, our widget might have child widgets. Include
550  // them, too.
551  if (view_->GetWidget()->GetRootView() == view_) {
552    std::vector<Widget*> child_widgets;
553    PopulateChildWidgetVector(&child_widgets);
554    *child_count += child_widgets.size();
555  }
556
557  return S_OK;
558}
559
560STDMETHODIMP NativeViewAccessibilityWin::get_accDefaultAction(
561    VARIANT var_id, BSTR* def_action) {
562  if (!IsValidId(var_id) || !def_action)
563    return E_INVALIDARG;
564
565  if (!view_)
566    return E_FAIL;
567
568  ui::AXViewState state;
569  view_->GetAccessibleState(&state);
570  base::string16 temp_action = state.default_action;
571
572  if (!temp_action.empty()) {
573    *def_action = SysAllocString(temp_action.c_str());
574  } else {
575    return S_FALSE;
576  }
577
578  return S_OK;
579}
580
581STDMETHODIMP NativeViewAccessibilityWin::get_accDescription(
582    VARIANT var_id, BSTR* desc) {
583  if (!IsValidId(var_id) || !desc)
584    return E_INVALIDARG;
585
586  if (!view_)
587    return E_FAIL;
588
589  base::string16 temp_desc;
590
591  view_->GetTooltipText(gfx::Point(), &temp_desc);
592  if (!temp_desc.empty()) {
593    *desc = SysAllocString(temp_desc.c_str());
594  } else {
595    return S_FALSE;
596  }
597
598  return S_OK;
599}
600
601STDMETHODIMP NativeViewAccessibilityWin::get_accFocus(VARIANT* focus_child) {
602  if (!focus_child)
603    return E_INVALIDARG;
604
605  if (!view_)
606    return E_FAIL;
607
608  FocusManager* focus_manager = view_->GetFocusManager();
609  View* focus = focus_manager ? focus_manager->GetFocusedView() : NULL;
610  if (focus == view_) {
611    // This view has focus.
612    focus_child->vt = VT_I4;
613    focus_child->lVal = CHILDID_SELF;
614  } else if (focus && view_->Contains(focus)) {
615    // Return the child object that has the keyboard focus.
616    focus_child->vt = VT_DISPATCH;
617    focus_child->pdispVal = focus->GetNativeViewAccessible();
618    focus_child->pdispVal->AddRef();
619    return S_OK;
620  } else {
621    // Neither this object nor any of its children has the keyboard focus.
622    focus_child->vt = VT_EMPTY;
623  }
624  return S_OK;
625}
626
627STDMETHODIMP NativeViewAccessibilityWin::get_accKeyboardShortcut(
628    VARIANT var_id, BSTR* acc_key) {
629  if (!IsValidId(var_id) || !acc_key)
630    return E_INVALIDARG;
631
632  if (!view_)
633    return E_FAIL;
634
635  ui::AXViewState state;
636  view_->GetAccessibleState(&state);
637  base::string16 temp_key = state.keyboard_shortcut;
638
639  if (!temp_key.empty()) {
640    *acc_key = SysAllocString(temp_key.c_str());
641  } else {
642    return S_FALSE;
643  }
644
645  return S_OK;
646}
647
648STDMETHODIMP NativeViewAccessibilityWin::get_accName(
649    VARIANT var_id, BSTR* name) {
650  if (!IsValidId(var_id) || !name)
651    return E_INVALIDARG;
652
653  if (!view_)
654    return E_FAIL;
655
656  // Retrieve the current view's name.
657  ui::AXViewState state;
658  view_->GetAccessibleState(&state);
659  base::string16 temp_name = state.name;
660  if (!temp_name.empty()) {
661    // Return name retrieved.
662    *name = SysAllocString(temp_name.c_str());
663  } else {
664    // If view has no name, return S_FALSE.
665    return S_FALSE;
666  }
667
668  return S_OK;
669}
670
671STDMETHODIMP NativeViewAccessibilityWin::get_accParent(
672    IDispatch** disp_parent) {
673  if (!disp_parent)
674    return E_INVALIDARG;
675
676  if (!view_)
677    return E_FAIL;
678
679  *disp_parent = NULL;
680  View* parent_view = view_->parent();
681
682  if (!parent_view) {
683    HWND hwnd = HWNDForView(view_);
684    if (!hwnd)
685      return S_FALSE;
686
687    return ::AccessibleObjectFromWindow(
688        hwnd, OBJID_WINDOW, IID_IAccessible,
689        reinterpret_cast<void**>(disp_parent));
690  }
691
692  *disp_parent = parent_view->GetNativeViewAccessible();
693  (*disp_parent)->AddRef();
694  return S_OK;
695}
696
697STDMETHODIMP NativeViewAccessibilityWin::get_accRole(
698    VARIANT var_id, VARIANT* role) {
699  if (!IsValidId(var_id) || !role)
700    return E_INVALIDARG;
701
702  if (!view_)
703    return E_FAIL;
704
705  ui::AXViewState state;
706  view_->GetAccessibleState(&state);
707  role->vt = VT_I4;
708  role->lVal = MSAARole(state.role);
709  return S_OK;
710}
711
712STDMETHODIMP NativeViewAccessibilityWin::get_accState(
713    VARIANT var_id, VARIANT* state) {
714  // This returns MSAA states. See also the IAccessible2 interface
715  // get_states().
716
717  if (!IsValidId(var_id) || !state)
718    return E_INVALIDARG;
719
720  if (!view_)
721    return E_FAIL;
722
723  state->vt = VT_I4;
724
725  // Retrieve all currently applicable states of the parent.
726  SetState(state, view_);
727
728  // Make sure that state is not empty, and has the proper type.
729  if (state->vt == VT_EMPTY)
730    return E_FAIL;
731
732  return S_OK;
733}
734
735STDMETHODIMP NativeViewAccessibilityWin::get_accValue(VARIANT var_id,
736                                                      BSTR* value) {
737  if (!IsValidId(var_id) || !value)
738    return E_INVALIDARG;
739
740  if (!view_)
741    return E_FAIL;
742
743  // Retrieve the current view's value.
744  ui::AXViewState state;
745  view_->GetAccessibleState(&state);
746  base::string16 temp_value = state.value;
747
748  if (!temp_value.empty()) {
749    // Return value retrieved.
750    *value = SysAllocString(temp_value.c_str());
751  } else {
752    // If view has no value, fall back into the default implementation.
753    *value = NULL;
754    return E_NOTIMPL;
755  }
756
757  return S_OK;
758}
759
760STDMETHODIMP NativeViewAccessibilityWin::put_accValue(VARIANT var_id,
761                                                      BSTR new_value) {
762  if (!IsValidId(var_id) || !new_value)
763    return E_INVALIDARG;
764
765  if (!view_)
766    return E_FAIL;
767
768  // Return an error if the view can't set the value.
769  ui::AXViewState state;
770  view_->GetAccessibleState(&state);
771  if (state.set_value_callback.is_null())
772    return E_FAIL;
773
774  state.set_value_callback.Run(new_value);
775  return S_OK;
776}
777
778// IAccessible functions not supported.
779
780STDMETHODIMP NativeViewAccessibilityWin::get_accSelection(VARIANT* selected) {
781  if (selected)
782    selected->vt = VT_EMPTY;
783  return E_NOTIMPL;
784}
785
786STDMETHODIMP NativeViewAccessibilityWin::accSelect(
787    LONG flagsSelect, VARIANT var_id) {
788  return E_NOTIMPL;
789}
790
791STDMETHODIMP NativeViewAccessibilityWin::get_accHelp(
792    VARIANT var_id, BSTR* help) {
793  base::string16 temp = base::UTF8ToUTF16(view_->GetClassName());
794  *help = SysAllocString(temp.c_str());
795  return S_OK;
796}
797
798STDMETHODIMP NativeViewAccessibilityWin::get_accHelpTopic(
799    BSTR* help_file, VARIANT var_id, LONG* topic_id) {
800  if (help_file) {
801    *help_file = NULL;
802  }
803  if (topic_id) {
804    *topic_id = static_cast<LONG>(-1);
805  }
806  return E_NOTIMPL;
807}
808
809STDMETHODIMP NativeViewAccessibilityWin::put_accName(
810    VARIANT var_id, BSTR put_name) {
811  // Deprecated.
812  return E_NOTIMPL;
813}
814
815//
816// IAccessible2
817//
818
819STDMETHODIMP NativeViewAccessibilityWin::role(LONG* role) {
820  if (!view_)
821    return E_FAIL;
822
823  if (!role)
824    return E_INVALIDARG;
825
826  ui::AXViewState state;
827  view_->GetAccessibleState(&state);
828  *role = MSAARole(state.role);
829  return S_OK;
830}
831
832STDMETHODIMP NativeViewAccessibilityWin::get_states(AccessibleStates* states) {
833  // This returns IAccessible2 states, which supplement MSAA states.
834  // See also the MSAA interface get_accState.
835
836  if (!view_)
837    return E_FAIL;
838
839  if (!states)
840    return E_INVALIDARG;
841
842  ui::AXViewState state;
843  view_->GetAccessibleState(&state);
844
845  // There are only a couple of states we need to support
846  // in IAccessible2. If any more are added, we may want to
847  // add a helper function like MSAAState.
848  *states = IA2_STATE_OPAQUE;
849  if (state.HasStateFlag(ui::AX_STATE_EDITABLE))
850    *states |= IA2_STATE_EDITABLE;
851
852  return S_OK;
853}
854
855STDMETHODIMP NativeViewAccessibilityWin::get_uniqueID(LONG* unique_id) {
856  if (!view_)
857    return E_FAIL;
858
859  if (!unique_id)
860    return E_INVALIDARG;
861
862  *unique_id = unique_id_;
863  return S_OK;
864}
865
866STDMETHODIMP NativeViewAccessibilityWin::get_windowHandle(HWND* window_handle) {
867  if (!view_)
868    return E_FAIL;
869
870  if (!window_handle)
871    return E_INVALIDARG;
872
873  *window_handle = HWNDForView(view_);
874  return *window_handle ? S_OK : S_FALSE;
875}
876
877STDMETHODIMP NativeViewAccessibilityWin::get_relationTargetsOfType(
878    BSTR type_bstr,
879    long max_targets,
880    IUnknown ***targets,
881    long *n_targets) {
882  if (!view_)
883    return E_FAIL;
884
885  if (!targets || !n_targets)
886    return E_INVALIDARG;
887
888  *n_targets = 0;
889  *targets = NULL;
890
891  // Only respond to requests for relations of type "alerts" on the
892  // root view.
893  base::string16 type(type_bstr);
894  if (type != L"alerts" || view_->parent())
895    return S_FALSE;
896
897  // Collect all of the alert views that are still valid.
898  std::vector<View*> alert_views;
899  ViewStorage* view_storage = ViewStorage::GetInstance();
900  for (size_t i = 0; i < alert_target_view_storage_ids_.size(); ++i) {
901    int view_storage_id = alert_target_view_storage_ids_[i];
902    View* view = view_storage->RetrieveView(view_storage_id);
903    if (!view || !view_->Contains(view))
904      continue;
905    alert_views.push_back(view);
906  }
907
908  long count = alert_views.size();
909  if (count == 0)
910    return S_FALSE;
911
912  // Don't return more targets than max_targets - but note that the caller
913  // is allowed to specify max_targets=0 to mean no limit.
914  if (max_targets > 0 && count > max_targets)
915    count = max_targets;
916
917  // Return the number of targets.
918  *n_targets = count;
919
920  // Allocate COM memory for the result array and populate it.
921  *targets = static_cast<IUnknown**>(
922      CoTaskMemAlloc(count * sizeof(IUnknown*)));
923  for (long i = 0; i < count; ++i) {
924    (*targets)[i] = alert_views[i]->GetNativeViewAccessible();
925    (*targets)[i]->AddRef();
926  }
927  return S_OK;
928}
929
930STDMETHODIMP NativeViewAccessibilityWin::get_attributes(BSTR* attributes) {
931  if (!view_)
932    return E_FAIL;
933
934  if (!attributes)
935    return E_INVALIDARG;
936
937  base::string16 attributes_str;
938
939  // Text fields need to report the attribute "text-model:a1" to instruct
940  // screen readers to use IAccessible2 APIs to handle text editing in this
941  // object (as opposed to treating it like a native Windows text box).
942  // The text-model:a1 attribute is documented here:
943  // http://www.linuxfoundation.org/collaborate/workgroups/accessibility/ia2/ia2_implementation_guide
944  ui::AXViewState state;
945  view_->GetAccessibleState(&state);
946  if (state.role == ui::AX_ROLE_TEXT_FIELD) {
947    attributes_str = L"text-model:a1;";
948  }
949
950  *attributes = SysAllocString(attributes_str.c_str());
951  DCHECK(*attributes);
952  return S_OK;
953}
954
955//
956// IAccessibleText
957//
958
959STDMETHODIMP NativeViewAccessibilityWin::get_nCharacters(LONG* n_characters) {
960  if (!view_)
961    return E_FAIL;
962
963  if (!n_characters)
964    return E_INVALIDARG;
965
966  base::string16 text = TextForIAccessibleText();
967  *n_characters = static_cast<LONG>(text.size());
968  return S_OK;
969}
970
971STDMETHODIMP NativeViewAccessibilityWin::get_caretOffset(LONG* offset) {
972  if (!view_)
973    return E_FAIL;
974
975  if (!offset)
976    return E_INVALIDARG;
977
978  ui::AXViewState state;
979  view_->GetAccessibleState(&state);
980  *offset = static_cast<LONG>(state.selection_end);
981  return S_OK;
982}
983
984STDMETHODIMP NativeViewAccessibilityWin::get_nSelections(LONG* n_selections) {
985  if (!view_)
986    return E_FAIL;
987
988  if (!n_selections)
989    return E_INVALIDARG;
990
991  ui::AXViewState state;
992  view_->GetAccessibleState(&state);
993  if (state.selection_start != state.selection_end)
994    *n_selections = 1;
995  else
996    *n_selections = 0;
997  return S_OK;
998}
999
1000STDMETHODIMP NativeViewAccessibilityWin::get_selection(LONG selection_index,
1001                                                      LONG* start_offset,
1002                                                      LONG* end_offset) {
1003  if (!view_)
1004    return E_FAIL;
1005
1006  if (!start_offset || !end_offset || selection_index != 0)
1007    return E_INVALIDARG;
1008
1009  ui::AXViewState state;
1010  view_->GetAccessibleState(&state);
1011  *start_offset = static_cast<LONG>(state.selection_start);
1012  *end_offset = static_cast<LONG>(state.selection_end);
1013  return S_OK;
1014}
1015
1016STDMETHODIMP NativeViewAccessibilityWin::get_text(LONG start_offset,
1017                                                  LONG end_offset,
1018                                                  BSTR* text) {
1019  if (!view_)
1020    return E_FAIL;
1021
1022  ui::AXViewState state;
1023  view_->GetAccessibleState(&state);
1024  base::string16 text_str = TextForIAccessibleText();
1025  LONG len = static_cast<LONG>(text_str.size());
1026
1027  if (start_offset == IA2_TEXT_OFFSET_LENGTH) {
1028    start_offset = len;
1029  } else if (start_offset == IA2_TEXT_OFFSET_CARET) {
1030    start_offset = static_cast<LONG>(state.selection_end);
1031  }
1032  if (end_offset == IA2_TEXT_OFFSET_LENGTH) {
1033    end_offset = static_cast<LONG>(text_str.size());
1034  } else if (end_offset == IA2_TEXT_OFFSET_CARET) {
1035    end_offset = static_cast<LONG>(state.selection_end);
1036  }
1037
1038  // The spec allows the arguments to be reversed.
1039  if (start_offset > end_offset) {
1040    LONG tmp = start_offset;
1041    start_offset = end_offset;
1042    end_offset = tmp;
1043  }
1044
1045  // The spec does not allow the start or end offsets to be out or range;
1046  // we must return an error if so.
1047  if (start_offset < 0)
1048    return E_INVALIDARG;
1049  if (end_offset > len)
1050    return E_INVALIDARG;
1051
1052  base::string16 substr =
1053      text_str.substr(start_offset, end_offset - start_offset);
1054  if (substr.empty())
1055    return S_FALSE;
1056
1057  *text = SysAllocString(substr.c_str());
1058  DCHECK(*text);
1059  return S_OK;
1060}
1061
1062STDMETHODIMP NativeViewAccessibilityWin::get_textAtOffset(
1063    LONG offset,
1064    enum IA2TextBoundaryType boundary_type,
1065    LONG* start_offset, LONG* end_offset,
1066    BSTR* text) {
1067  if (!start_offset || !end_offset || !text)
1068    return E_INVALIDARG;
1069
1070  // The IAccessible2 spec says we don't have to implement the "sentence"
1071  // boundary type, we can just let the screenreader handle it.
1072  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
1073    *start_offset = 0;
1074    *end_offset = 0;
1075    *text = NULL;
1076    return S_FALSE;
1077  }
1078
1079  const base::string16& text_str = TextForIAccessibleText();
1080
1081  *start_offset = FindBoundary(
1082      text_str, boundary_type, offset, ui::BACKWARDS_DIRECTION);
1083  *end_offset = FindBoundary(
1084      text_str, boundary_type, offset, ui::FORWARDS_DIRECTION);
1085  return get_text(*start_offset, *end_offset, text);
1086}
1087
1088STDMETHODIMP NativeViewAccessibilityWin::get_textBeforeOffset(
1089    LONG offset,
1090    enum IA2TextBoundaryType boundary_type,
1091    LONG* start_offset, LONG* end_offset,
1092    BSTR* text) {
1093  if (!start_offset || !end_offset || !text)
1094    return E_INVALIDARG;
1095
1096  // The IAccessible2 spec says we don't have to implement the "sentence"
1097  // boundary type, we can just let the screenreader handle it.
1098  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
1099    *start_offset = 0;
1100    *end_offset = 0;
1101    *text = NULL;
1102    return S_FALSE;
1103  }
1104
1105  const base::string16& text_str = TextForIAccessibleText();
1106
1107  *start_offset = FindBoundary(
1108      text_str, boundary_type, offset, ui::BACKWARDS_DIRECTION);
1109  *end_offset = offset;
1110  return get_text(*start_offset, *end_offset, text);
1111}
1112
1113STDMETHODIMP NativeViewAccessibilityWin::get_textAfterOffset(
1114    LONG offset,
1115    enum IA2TextBoundaryType boundary_type,
1116    LONG* start_offset, LONG* end_offset,
1117    BSTR* text) {
1118  if (!start_offset || !end_offset || !text)
1119    return E_INVALIDARG;
1120
1121  // The IAccessible2 spec says we don't have to implement the "sentence"
1122  // boundary type, we can just let the screenreader handle it.
1123  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
1124    *start_offset = 0;
1125    *end_offset = 0;
1126    *text = NULL;
1127    return S_FALSE;
1128  }
1129
1130  const base::string16& text_str = TextForIAccessibleText();
1131
1132  *start_offset = offset;
1133  *end_offset = FindBoundary(
1134      text_str, boundary_type, offset, ui::FORWARDS_DIRECTION);
1135  return get_text(*start_offset, *end_offset, text);
1136}
1137
1138STDMETHODIMP NativeViewAccessibilityWin::get_offsetAtPoint(
1139    LONG x, LONG y, enum IA2CoordinateType coord_type, LONG* offset) {
1140  if (!view_)
1141    return E_FAIL;
1142
1143  if (!offset)
1144    return E_INVALIDARG;
1145
1146  // We don't support this method, but we have to return something
1147  // rather than E_NOTIMPL or screen readers will complain.
1148  *offset = 0;
1149  return S_OK;
1150}
1151
1152//
1153// IServiceProvider methods.
1154//
1155
1156STDMETHODIMP NativeViewAccessibilityWin::QueryService(
1157    REFGUID guidService, REFIID riid, void** object) {
1158  if (!view_)
1159    return E_FAIL;
1160
1161  if (riid == IID_IAccessible2 || riid == IID_IAccessible2_2)
1162    AccessibleWebViewRegistry::GetInstance()->EnableIAccessible2Support();
1163
1164  if (guidService == IID_IAccessible ||
1165      guidService == IID_IAccessible2 ||
1166      guidService == IID_IAccessible2_2 ||
1167      guidService == IID_IAccessibleText)  {
1168    return QueryInterface(riid, object);
1169  }
1170
1171  // We only support the IAccessibleEx interface on Windows 8 and above. This
1172  // is needed for the On screen Keyboard to show up in metro mode, when the
1173  // user taps an editable region in the window.
1174  // All methods in the IAccessibleEx interface are unimplemented.
1175  if (riid == IID_IAccessibleEx &&
1176      base::win::GetVersion() >= base::win::VERSION_WIN8) {
1177    return QueryInterface(riid, object);
1178  }
1179
1180  *object = NULL;
1181  return E_FAIL;
1182}
1183
1184STDMETHODIMP NativeViewAccessibilityWin::GetPatternProvider(
1185    PATTERNID id, IUnknown** provider) {
1186  DVLOG(1) << "In Function: "
1187           << __FUNCTION__
1188           << " for pattern id: "
1189           << id;
1190  if (id == UIA_ValuePatternId || id == UIA_TextPatternId) {
1191    ui::AXViewState state;
1192    view_->GetAccessibleState(&state);
1193    long role = MSAARole(state.role);
1194
1195    if (role == ROLE_SYSTEM_TEXT) {
1196      DVLOG(1) << "Returning UIA text provider";
1197      base::win::UIATextProvider::CreateTextProvider(
1198          state.value, true, provider);
1199      return S_OK;
1200    }
1201  }
1202  return E_NOTIMPL;
1203}
1204
1205STDMETHODIMP NativeViewAccessibilityWin::GetPropertyValue(PROPERTYID id,
1206                                                          VARIANT* ret) {
1207  DVLOG(1) << "In Function: "
1208           << __FUNCTION__
1209           << " for property id: "
1210           << id;
1211  if (id == UIA_ControlTypePropertyId) {
1212    ui::AXViewState state;
1213    view_->GetAccessibleState(&state);
1214    long role = MSAARole(state.role);
1215    if (role == ROLE_SYSTEM_TEXT) {
1216      V_VT(ret) = VT_I4;
1217      ret->lVal = UIA_EditControlTypeId;
1218      DVLOG(1) << "Returning Edit control type";
1219    } else {
1220      DVLOG(1) << "Returning empty control type";
1221      V_VT(ret) = VT_EMPTY;
1222    }
1223  } else {
1224    V_VT(ret) = VT_EMPTY;
1225  }
1226  return S_OK;
1227}
1228
1229//
1230// Static methods.
1231//
1232
1233void NativeViewAccessibility::RegisterWebView(View* web_view) {
1234  AccessibleWebViewRegistry::GetInstance()->RegisterWebView(web_view);
1235}
1236
1237void NativeViewAccessibility::UnregisterWebView(View* web_view) {
1238  AccessibleWebViewRegistry::GetInstance()->UnregisterWebView(web_view);
1239}
1240
1241int32 NativeViewAccessibilityWin::MSAAEvent(ui::AXEvent event) {
1242  switch (event) {
1243    case ui::AX_EVENT_ALERT:
1244      return EVENT_SYSTEM_ALERT;
1245    case ui::AX_EVENT_FOCUS:
1246      return EVENT_OBJECT_FOCUS;
1247    case ui::AX_EVENT_MENU_START:
1248      return EVENT_SYSTEM_MENUSTART;
1249    case ui::AX_EVENT_MENU_END:
1250      return EVENT_SYSTEM_MENUEND;
1251    case ui::AX_EVENT_MENU_POPUP_START:
1252      return EVENT_SYSTEM_MENUPOPUPSTART;
1253    case ui::AX_EVENT_MENU_POPUP_END:
1254      return EVENT_SYSTEM_MENUPOPUPEND;
1255    case ui::AX_EVENT_SELECTION:
1256      return EVENT_OBJECT_SELECTION;
1257    case ui::AX_EVENT_SELECTION_ADD:
1258      return EVENT_OBJECT_SELECTIONADD;
1259    case ui::AX_EVENT_SELECTION_REMOVE:
1260      return EVENT_OBJECT_SELECTIONREMOVE;
1261    case ui::AX_EVENT_TEXT_CHANGED:
1262      return EVENT_OBJECT_NAMECHANGE;
1263    case ui::AX_EVENT_TEXT_SELECTION_CHANGED:
1264      return IA2_EVENT_TEXT_CARET_MOVED;
1265    case ui::AX_EVENT_VALUE_CHANGED:
1266      return EVENT_OBJECT_VALUECHANGE;
1267    default:
1268      // Not supported or invalid event.
1269      NOTREACHED();
1270      return -1;
1271  }
1272}
1273
1274int32 NativeViewAccessibilityWin::MSAARole(ui::AXRole role) {
1275  switch (role) {
1276    case ui::AX_ROLE_ALERT:
1277      return ROLE_SYSTEM_ALERT;
1278    case ui::AX_ROLE_APPLICATION:
1279      return ROLE_SYSTEM_APPLICATION;
1280    case ui::AX_ROLE_BUTTON_DROP_DOWN:
1281      return ROLE_SYSTEM_BUTTONDROPDOWN;
1282    case ui::AX_ROLE_POP_UP_BUTTON:
1283      return ROLE_SYSTEM_BUTTONMENU;
1284    case ui::AX_ROLE_CHECK_BOX:
1285      return ROLE_SYSTEM_CHECKBUTTON;
1286    case ui::AX_ROLE_COMBO_BOX:
1287      return ROLE_SYSTEM_COMBOBOX;
1288    case ui::AX_ROLE_DIALOG:
1289      return ROLE_SYSTEM_DIALOG;
1290    case ui::AX_ROLE_GROUP:
1291      return ROLE_SYSTEM_GROUPING;
1292    case ui::AX_ROLE_IMAGE:
1293      return ROLE_SYSTEM_GRAPHIC;
1294    case ui::AX_ROLE_LINK:
1295      return ROLE_SYSTEM_LINK;
1296    case ui::AX_ROLE_LOCATION_BAR:
1297      return ROLE_SYSTEM_GROUPING;
1298    case ui::AX_ROLE_MENU_BAR:
1299      return ROLE_SYSTEM_MENUBAR;
1300    case ui::AX_ROLE_MENU_ITEM:
1301      return ROLE_SYSTEM_MENUITEM;
1302    case ui::AX_ROLE_MENU_LIST_POPUP:
1303      return ROLE_SYSTEM_MENUPOPUP;
1304    case ui::AX_ROLE_TREE:
1305      return ROLE_SYSTEM_OUTLINE;
1306    case ui::AX_ROLE_TREE_ITEM:
1307      return ROLE_SYSTEM_OUTLINEITEM;
1308    case ui::AX_ROLE_TAB:
1309      return ROLE_SYSTEM_PAGETAB;
1310    case ui::AX_ROLE_TAB_LIST:
1311      return ROLE_SYSTEM_PAGETABLIST;
1312    case ui::AX_ROLE_PANE:
1313      return ROLE_SYSTEM_PANE;
1314    case ui::AX_ROLE_PROGRESS_INDICATOR:
1315      return ROLE_SYSTEM_PROGRESSBAR;
1316    case ui::AX_ROLE_BUTTON:
1317      return ROLE_SYSTEM_PUSHBUTTON;
1318    case ui::AX_ROLE_RADIO_BUTTON:
1319      return ROLE_SYSTEM_RADIOBUTTON;
1320    case ui::AX_ROLE_SCROLL_BAR:
1321      return ROLE_SYSTEM_SCROLLBAR;
1322    case ui::AX_ROLE_SPLITTER:
1323      return ROLE_SYSTEM_SEPARATOR;
1324    case ui::AX_ROLE_SLIDER:
1325      return ROLE_SYSTEM_SLIDER;
1326    case ui::AX_ROLE_STATIC_TEXT:
1327      return ROLE_SYSTEM_STATICTEXT;
1328    case ui::AX_ROLE_TEXT_FIELD:
1329      return ROLE_SYSTEM_TEXT;
1330    case ui::AX_ROLE_TITLE_BAR:
1331      return ROLE_SYSTEM_TITLEBAR;
1332    case ui::AX_ROLE_TOOLBAR:
1333      return ROLE_SYSTEM_TOOLBAR;
1334    case ui::AX_ROLE_WINDOW:
1335      return ROLE_SYSTEM_WINDOW;
1336    case ui::AX_ROLE_CLIENT:
1337    default:
1338      // This is the default role for MSAA.
1339      return ROLE_SYSTEM_CLIENT;
1340  }
1341}
1342
1343int32 NativeViewAccessibilityWin::MSAAState(const ui::AXViewState& state) {
1344  // This maps MSAA states for get_accState(). See also the IAccessible2
1345  // interface get_states().
1346
1347  int32 msaa_state = 0;
1348  if (state.HasStateFlag(ui::AX_STATE_CHECKED))
1349    msaa_state |= STATE_SYSTEM_CHECKED;
1350  if (state.HasStateFlag(ui::AX_STATE_COLLAPSED))
1351    msaa_state |= STATE_SYSTEM_COLLAPSED;
1352  if (state.HasStateFlag(ui::AX_STATE_DEFAULT))
1353    msaa_state |= STATE_SYSTEM_DEFAULT;
1354  if (state.HasStateFlag(ui::AX_STATE_EXPANDED))
1355    msaa_state |= STATE_SYSTEM_EXPANDED;
1356  if (state.HasStateFlag(ui::AX_STATE_HASPOPUP))
1357    msaa_state |= STATE_SYSTEM_HASPOPUP;
1358  if (state.HasStateFlag(ui::AX_STATE_HOVERED))
1359    msaa_state |= STATE_SYSTEM_HOTTRACKED;
1360  if (state.HasStateFlag(ui::AX_STATE_INVISIBLE))
1361    msaa_state |= STATE_SYSTEM_INVISIBLE;
1362  if (state.HasStateFlag(ui::AX_STATE_LINKED))
1363    msaa_state |= STATE_SYSTEM_LINKED;
1364  if (state.HasStateFlag(ui::AX_STATE_OFFSCREEN))
1365    msaa_state |= STATE_SYSTEM_OFFSCREEN;
1366  if (state.HasStateFlag(ui::AX_STATE_PRESSED))
1367    msaa_state |= STATE_SYSTEM_PRESSED;
1368  if (state.HasStateFlag(ui::AX_STATE_PROTECTED))
1369    msaa_state |= STATE_SYSTEM_PROTECTED;
1370  if (state.HasStateFlag(ui::AX_STATE_READ_ONLY))
1371    msaa_state |= STATE_SYSTEM_READONLY;
1372  if (state.HasStateFlag(ui::AX_STATE_SELECTABLE))
1373    msaa_state |= STATE_SYSTEM_SELECTABLE;
1374  if (state.HasStateFlag(ui::AX_STATE_SELECTED))
1375    msaa_state |= STATE_SYSTEM_SELECTED;
1376  if (state.HasStateFlag(ui::AX_STATE_FOCUSED))
1377    msaa_state |= STATE_SYSTEM_FOCUSED;
1378  if (state.HasStateFlag(ui::AX_STATE_DISABLED))
1379    msaa_state |= STATE_SYSTEM_UNAVAILABLE;
1380  return msaa_state;
1381}
1382
1383//
1384// Private methods.
1385//
1386
1387bool NativeViewAccessibilityWin::IsNavDirNext(int nav_dir) const {
1388  return (nav_dir == NAVDIR_RIGHT ||
1389          nav_dir == NAVDIR_DOWN ||
1390          nav_dir == NAVDIR_NEXT);
1391}
1392
1393bool NativeViewAccessibilityWin::IsValidNav(
1394    int nav_dir, int start_id, int lower_bound, int upper_bound) const {
1395  if (IsNavDirNext(nav_dir)) {
1396    if ((start_id + 1) > upper_bound) {
1397      return false;
1398    }
1399  } else {
1400    if ((start_id - 1) <= lower_bound) {
1401      return false;
1402    }
1403  }
1404  return true;
1405}
1406
1407bool NativeViewAccessibilityWin::IsValidId(const VARIANT& child) const {
1408  // View accessibility returns an IAccessible for each view so we only support
1409  // the CHILDID_SELF id.
1410  return (VT_I4 == child.vt) && (CHILDID_SELF == child.lVal);
1411}
1412
1413void NativeViewAccessibilityWin::SetState(
1414    VARIANT* msaa_state, View* view) {
1415  // Ensure the output param is initialized to zero.
1416  msaa_state->lVal = 0;
1417
1418  // Default state; all views can have accessibility focus.
1419  msaa_state->lVal |= STATE_SYSTEM_FOCUSABLE;
1420
1421  if (!view)
1422    return;
1423
1424  if (!view->enabled())
1425    msaa_state->lVal |= STATE_SYSTEM_UNAVAILABLE;
1426  if (!view->visible())
1427    msaa_state->lVal |= STATE_SYSTEM_INVISIBLE;
1428  if (!strcmp(view->GetClassName(), CustomButton::kViewClassName)) {
1429    CustomButton* button = static_cast<CustomButton*>(view);
1430    if (button->IsHotTracked())
1431      msaa_state->lVal |= STATE_SYSTEM_HOTTRACKED;
1432  }
1433  if (view->HasFocus())
1434    msaa_state->lVal |= STATE_SYSTEM_FOCUSED;
1435
1436  // Add on any view-specific states.
1437  ui::AXViewState view_state;
1438  view->GetAccessibleState(&view_state);
1439  msaa_state->lVal |= MSAAState(view_state);
1440}
1441
1442base::string16 NativeViewAccessibilityWin::TextForIAccessibleText() {
1443  ui::AXViewState state;
1444  view_->GetAccessibleState(&state);
1445  if (state.role == ui::AX_ROLE_TEXT_FIELD)
1446    return state.value;
1447  else
1448    return state.name;
1449}
1450
1451void NativeViewAccessibilityWin::HandleSpecialTextOffset(
1452    const base::string16& text, LONG* offset) {
1453  if (*offset == IA2_TEXT_OFFSET_LENGTH) {
1454    *offset = static_cast<LONG>(text.size());
1455  } else if (*offset == IA2_TEXT_OFFSET_CARET) {
1456    get_caretOffset(offset);
1457  }
1458}
1459
1460ui::TextBoundaryType NativeViewAccessibilityWin::IA2TextBoundaryToTextBoundary(
1461    IA2TextBoundaryType ia2_boundary) {
1462  switch(ia2_boundary) {
1463    case IA2_TEXT_BOUNDARY_CHAR: return ui::CHAR_BOUNDARY;
1464    case IA2_TEXT_BOUNDARY_WORD: return ui::WORD_BOUNDARY;
1465    case IA2_TEXT_BOUNDARY_LINE: return ui::LINE_BOUNDARY;
1466    case IA2_TEXT_BOUNDARY_SENTENCE: return ui::SENTENCE_BOUNDARY;
1467    case IA2_TEXT_BOUNDARY_PARAGRAPH: return ui::PARAGRAPH_BOUNDARY;
1468    case IA2_TEXT_BOUNDARY_ALL: return ui::ALL_BOUNDARY;
1469    default:
1470      NOTREACHED();
1471      return ui::CHAR_BOUNDARY;
1472  }
1473}
1474
1475LONG NativeViewAccessibilityWin::FindBoundary(
1476    const base::string16& text,
1477    IA2TextBoundaryType ia2_boundary,
1478    LONG start_offset,
1479    ui::TextBoundaryDirection direction) {
1480  HandleSpecialTextOffset(text, &start_offset);
1481  ui::TextBoundaryType boundary = IA2TextBoundaryToTextBoundary(ia2_boundary);
1482  std::vector<int32> line_breaks;
1483  return ui::FindAccessibleTextBoundary(
1484      text, line_breaks, boundary, start_offset, direction);
1485}
1486
1487void NativeViewAccessibilityWin::PopulateChildWidgetVector(
1488    std::vector<Widget*>* result_child_widgets) {
1489  const Widget* widget = view()->GetWidget();
1490  if (!widget)
1491    return;
1492
1493  std::set<Widget*> child_widgets;
1494  Widget::GetAllChildWidgets(widget->GetNativeView(), &child_widgets);
1495  Widget::GetAllOwnedWidgets(widget->GetNativeView(), &child_widgets);
1496  for (std::set<Widget*>::const_iterator iter = child_widgets.begin();
1497           iter != child_widgets.end(); ++iter) {
1498    Widget* child_widget = *iter;
1499    if (child_widget == widget)
1500      continue;
1501
1502    if (!child_widget->IsVisible())
1503      continue;
1504
1505    if (widget->GetNativeWindowProperty(kWidgetNativeViewHostKey))
1506      continue;
1507
1508    result_child_widgets->push_back(child_widget);
1509  }
1510}
1511
1512void NativeViewAccessibilityWin::AddAlertTarget() {
1513  ViewStorage* view_storage = ViewStorage::GetInstance();
1514  for (size_t i = 0; i < alert_target_view_storage_ids_.size(); ++i) {
1515    int view_storage_id = alert_target_view_storage_ids_[i];
1516    View* view = view_storage->RetrieveView(view_storage_id);
1517    if (view == view_)
1518      return;
1519  }
1520  int view_storage_id = view_storage->CreateStorageID();
1521  view_storage->StoreView(view_storage_id, view_);
1522  alert_target_view_storage_ids_.push_back(view_storage_id);
1523}
1524
1525void NativeViewAccessibilityWin::RemoveAlertTarget() {
1526  ViewStorage* view_storage = ViewStorage::GetInstance();
1527  size_t i = 0;
1528  while (i < alert_target_view_storage_ids_.size()) {
1529    int view_storage_id = alert_target_view_storage_ids_[i];
1530    View* view = view_storage->RetrieveView(view_storage_id);
1531    if (view == NULL || view == view_) {
1532      alert_target_view_storage_ids_.erase(
1533          alert_target_view_storage_ids_.begin() + i);
1534    } else {
1535      ++i;
1536    }
1537  }
1538}
1539
1540}  // namespace views
1541