Revert of Implement NativeViewAccessibilityWin using AXPlatformNodeWin.

ui/views/accessibility/native_view_accessibility_win.cc

Index: ui/views/accessibility/native_view_accessibility_win.cc
diff --git a/ui/views/accessibility/native_view_accessibility_win.cc b/ui/views/accessibility/native_view_accessibility_win.cc
index fd9edaa3e29d29e339861af10155a8e664abd714..1255f10068534e656c3f878202aa643f52d3fa0d 100644
--- a/ui/views/accessibility/native_view_accessibility_win.cc
+++ b/ui/views/accessibility/native_view_accessibility_win.cc
@@ -5,6 +5,7 @@
 #include "ui/views/accessibility/native_view_accessibility_win.h"
 
 #include <oleacc.h>
+#include <UIAutomationClient.h>
 
 #include <set>
 #include <vector>
@@ -17,6 +18,7 @@
 #include "ui/accessibility/ax_enums.h"
 #include "ui/accessibility/ax_text_utils.h"
 #include "ui/accessibility/ax_view_state.h"
+#include "ui/base/win/accessibility_ids_win.h"
 #include "ui/base/win/accessibility_misc_utils.h"
 #include "ui/base/win/atl_module.h"
 #include "ui/views/controls/button/custom_button.h"
@@ -26,40 +28,1531 @@
 #include "ui/views/win/hwnd_util.h"
 
 namespace views {
+namespace {
+
+class AccessibleWebViewRegistry {
+ public:
+  static AccessibleWebViewRegistry* GetInstance();
+
+  void RegisterWebView(View* web_view);
+
+  void UnregisterWebView(View* web_view);
+
+  // Given the view that received the request for the accessible
+  // id in |top_view|, and the child id requested, return the native
+  // accessible object with that child id from one of the WebViews in
+  // |top_view|'s view hierarchy, if any.
+  IAccessible* GetAccessibleFromWebView(View* top_view, long child_id);
+
+  // The system uses IAccessible APIs for many purposes, but only
+  // assistive technology like screen readers uses IAccessible2.
+  // Call this method to note that the IAccessible2 interface was queried and
+  // that WebViews should be proactively notified that this interface will be
+  // used. If this is enabled for the first time, this will explicitly call
+  // QueryService with an argument of IAccessible2 on all WebViews, otherwise
+  // it will just do it from now on.
+  void EnableIAccessible2Support();
+
+ private:
+  friend struct DefaultSingletonTraits<AccessibleWebViewRegistry>;
+  AccessibleWebViewRegistry();
+  ~AccessibleWebViewRegistry() {}
+
+  IAccessible* AccessibleObjectFromChildId(View* web_view, long child_id);
+
+  void QueryIAccessible2Interface(View* web_view);
+
+  // Set of all web views. We check whether each one is contained in a
+  // top view dynamically rather than keeping track of a map.
+  std::set<View*> web_views_;
+
+  // The most recent top view used in a call to GetAccessibleFromWebView.
+  View* last_top_view_;
+
+  // The most recent web view where an accessible object was found,
+  // corresponding to |last_top_view_|.
+  View* last_web_view_;
+
+  // If IAccessible2 support is enabled, we query the IAccessible2 interface
+  // of WebViews proactively when they're registered, so that they are
+  // aware that they need to support this interface.
+  bool iaccessible2_support_enabled_;
+
+  DISALLOW_COPY_AND_ASSIGN(AccessibleWebViewRegistry);
+};
+
+AccessibleWebViewRegistry::AccessibleWebViewRegistry()
+    : last_top_view_(NULL),
+      last_web_view_(NULL),
+      iaccessible2_support_enabled_(false) {
+}
+
+AccessibleWebViewRegistry* AccessibleWebViewRegistry::GetInstance() {
+  return Singleton<AccessibleWebViewRegistry>::get();
+}
+
+void AccessibleWebViewRegistry::RegisterWebView(View* web_view) {
+  DCHECK(web_views_.find(web_view) == web_views_.end());
+  web_views_.insert(web_view);
+
+  if (iaccessible2_support_enabled_)
+    QueryIAccessible2Interface(web_view);
+}
+
+void AccessibleWebViewRegistry::UnregisterWebView(View* web_view) {
+  DCHECK(web_views_.find(web_view) != web_views_.end());
+  web_views_.erase(web_view);
+  if (last_web_view_ == web_view) {
+    last_top_view_ = NULL;
+    last_web_view_ = NULL;
+  }
+}
+
+IAccessible* AccessibleWebViewRegistry::GetAccessibleFromWebView(
+    View* top_view, long child_id) {
+  // This function gets called frequently, so try to avoid searching all
+  // of the web views if the notification is on the same web view that
+  // sent the last one.
+  if (last_top_view_ == top_view) {
+    IAccessible* accessible =
+        AccessibleObjectFromChildId(last_web_view_, child_id);
+    if (accessible)
+      return accessible;
+  }
+
+  // Search all web views. For each one, first ensure it's a descendant
+  // of this view where the event was posted - and if so, see if it owns
+  // an accessible object with that child id. If so, save the view to speed
+  // up the next notification.
+  for (std::set<View*>::iterator iter = web_views_.begin();
+       iter != web_views_.end(); ++iter) {
+    View* web_view = *iter;
+    if (top_view == web_view || !top_view->Contains(web_view))
+      continue;
+    IAccessible* accessible = AccessibleObjectFromChildId(web_view, child_id);
+    if (accessible) {
+      last_top_view_ = top_view;
+      last_web_view_ = web_view;
+      return accessible;
+    }
+  }
+
+  return NULL;
+}
+
+void AccessibleWebViewRegistry::EnableIAccessible2Support() {
+  if (iaccessible2_support_enabled_)
+    return;
+  iaccessible2_support_enabled_ = true;
+  for (std::set<View*>::iterator iter = web_views_.begin();
+       iter != web_views_.end(); ++iter) {
+    QueryIAccessible2Interface(*iter);
+  }
+}
+
+IAccessible* AccessibleWebViewRegistry::AccessibleObjectFromChildId(
+    View* web_view,
+    long child_id) {
+  IAccessible* web_view_accessible = web_view->GetNativeViewAccessible();
+  if (web_view_accessible == NULL)
+    return NULL;
+
+  VARIANT var_child;
+  var_child.vt = VT_I4;
+  var_child.lVal = child_id;
+  IAccessible* result = NULL;
+  if (S_OK == web_view_accessible->get_accChild(
+      var_child, reinterpret_cast<IDispatch**>(&result))) {
+    return result;
+  }
+
+  return NULL;
+}
+
+void AccessibleWebViewRegistry::QueryIAccessible2Interface(View* web_view) {
+  IAccessible* web_view_accessible = web_view->GetNativeViewAccessible();
+  if (!web_view_accessible)
+    return;
+
+  base::win::ScopedComPtr<IServiceProvider> service_provider;
+  if (S_OK != web_view_accessible->QueryInterface(service_provider.Receive()))
+    return;
+  base::win::ScopedComPtr<IAccessible2> iaccessible2;
+  service_provider->QueryService(
+      IID_IAccessible, IID_IAccessible2,
+      reinterpret_cast<void**>(iaccessible2.Receive()));
+}
+
+}  // anonymous namespace
+
+// static
+long NativeViewAccessibilityWin::next_unique_id_ = 1;
+int NativeViewAccessibilityWin::view_storage_ids_[kMaxViewStorageIds] = {0};
+int NativeViewAccessibilityWin::next_view_storage_id_index_ = 0;
+std::vector<int> NativeViewAccessibilityWin::alert_target_view_storage_ids_;
 
 // static
 NativeViewAccessibility* NativeViewAccessibility::Create(View* view) {
-  return new NativeViewAccessibilityWin(view);
-}
-
-NativeViewAccessibilityWin::NativeViewAccessibilityWin(View* view)
-    : NativeViewAccessibility(view) {
+  // Make sure ATL is initialized in this module.
+  ui::win::CreateATLModuleIfNeeded();
+
+  CComObject<NativeViewAccessibilityWin>* instance = NULL;
+  HRESULT hr = CComObject<NativeViewAccessibilityWin>::CreateInstance(
+      &instance);
+  DCHECK(SUCCEEDED(hr));
+  instance->set_view(view);
+  instance->AddRef();
+  return instance;
+}
+
+NativeViewAccessibilityWin::NativeViewAccessibilityWin()
+    : unique_id_(next_unique_id_++) {
 }
 
 NativeViewAccessibilityWin::~NativeViewAccessibilityWin() {
-}
-
-gfx::NativeViewAccessible NativeViewAccessibilityWin::GetParent() {
-  IAccessible* parent = NativeViewAccessibility::GetParent();
-  if (parent)
-    return parent;
-
+  RemoveAlertTarget();
+}
+
+void NativeViewAccessibilityWin::NotifyAccessibilityEvent(
+    ui::AXEvent event_type) {
+  if (!view_)
+    return;
+
+  ViewStorage* view_storage = ViewStorage::GetInstance();
   HWND hwnd = HWNDForView(view_);
-  if (!hwnd)
-    return NULL;
-
-  HRESULT hr = ::AccessibleObjectFromWindow(
-      hwnd, OBJID_WINDOW, IID_IAccessible,
-      reinterpret_cast<void**>(&parent));
-  if (SUCCEEDED(hr))
-    return parent;
-
-  return NULL;
-}
-
-gfx::AcceleratedWidget
-NativeViewAccessibilityWin::GetTargetForNativeAccessibilityEvent() {
-  return HWNDForView(view_);
+  int view_storage_id = view_storage_ids_[next_view_storage_id_index_];
+  if (view_storage_id == 0) {
+    view_storage_id = view_storage->CreateStorageID();
+    view_storage_ids_[next_view_storage_id_index_] = view_storage_id;
+  } else {
+    view_storage->RemoveView(view_storage_id);
+  }
+  view_storage->StoreView(view_storage_id, view_);
+
+  // Positive child ids are used for enumerating direct children,
+  // negative child ids can be used as unique ids to refer to a specific
+  // descendants.  Make index into view_storage_ids_ into a negative child id.
+  int child_id =
+      base::win::kFirstViewsAccessibilityId - next_view_storage_id_index_;
+  ::NotifyWinEvent(MSAAEvent(event_type), hwnd, OBJID_CLIENT, child_id);
+  next_view_storage_id_index_ =
+      (next_view_storage_id_index_ + 1) % kMaxViewStorageIds;
+
+  // Keep track of views that are a target of an alert event.
+  if (event_type == ui::AX_EVENT_ALERT)
+    AddAlertTarget();
+}
+
+gfx::NativeViewAccessible NativeViewAccessibilityWin::GetNativeObject() {
+  return this;
+}
+
+void NativeViewAccessibilityWin::Destroy() {
+  view_ = NULL;
+  Release();
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::accHitTest(
+    LONG x_left, LONG y_top, VARIANT* child) {
+  if (!child)
+    return E_INVALIDARG;
+
+  if (!view_ || !view_->GetWidget())
+    return E_FAIL;
+
+  // If this is a root view, our widget might have child widgets.
+  // Search child widgets first, since they're on top in the z-order.
+  if (view_->GetWidget()->GetRootView() == view_) {
+    std::vector<Widget*> child_widgets;
+    PopulateChildWidgetVector(&child_widgets);
+    for (size_t i = 0; i < child_widgets.size(); ++i) {
+      Widget* child_widget = child_widgets[i];
+      IAccessible* child_accessible =
+          child_widget->GetRootView()->GetNativeViewAccessible();
+      HRESULT result = child_accessible->accHitTest(x_left, y_top, child);
+      if (result == S_OK)
+        return result;
+    }
+  }
+
+  gfx::Point point(x_left, y_top);
+  View::ConvertPointFromScreen(view_, &point);
+
+  // If the point is not inside this view, return false.
+  if (!view_->HitTestPoint(point)) {
+    child->vt = VT_EMPTY;
+    return S_FALSE;
+  }
+
+  // Check if the point is within any of the immediate children of this
+  // view.
+  View* hit_child_view = NULL;
+  for (int i = view_->child_count() - 1; i >= 0; --i) {
+    View* child_view = view_->child_at(i);
+    if (!child_view->visible())
+      continue;
+
+    gfx::Point point_in_child_coords(point);
+    view_->ConvertPointToTarget(view_, child_view, &point_in_child_coords);
+    if (child_view->HitTestPoint(point_in_child_coords)) {
+      hit_child_view = child_view;
+      break;
+    }
+  }
+
+  // If the point was within one of this view's immediate children,
+  // call accHitTest recursively on that child's native view accessible -
+  // which may be a recursive call to this function or it may be overridden,
+  // for example in the case of a WebView.
+  if (hit_child_view) {
+    HRESULT result = hit_child_view->GetNativeViewAccessible()->accHitTest(
+        x_left, y_top, child);
+
+    // If the recursive call returned CHILDID_SELF, we have to convert that
+    // into a VT_DISPATCH for the return value to this call.
+    if (S_OK == result && child->vt == VT_I4 && child->lVal == CHILDID_SELF) {
+      child->vt = VT_DISPATCH;
+      child->pdispVal = hit_child_view->GetNativeViewAccessible();
+      // Always increment ref when returning a reference to a COM object.
+      child->pdispVal->AddRef();
+    }
+    return result;
+  }
+
+  // This object is the best match, so return CHILDID_SELF. It's tempting to
+  // simplify the logic and use VT_DISPATCH everywhere, but the Windows
+  // call AccessibleObjectFromPoint will keep calling accHitTest until some
+  // object returns CHILDID_SELF.
+  child->vt = VT_I4;
+  child->lVal = CHILDID_SELF;
+  return S_OK;
+}
+
+HRESULT NativeViewAccessibilityWin::accDoDefaultAction(VARIANT var_id) {
+  if (!IsValidId(var_id))
+    return E_INVALIDARG;
+
+  // The object does not support the method. This value is returned for
+  // controls that do not perform actions, such as edit fields.
+  return DISP_E_MEMBERNOTFOUND;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::accLocation(
+    LONG* x_left, LONG* y_top, LONG* width, LONG* height, VARIANT var_id) {
+  if (!IsValidId(var_id) || !x_left || !y_top || !width || !height)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  if (!view_->bounds().IsEmpty()) {
+    *width  = view_->width();
+    *height = view_->height();
+    gfx::Point topleft(view_->bounds().origin());
+    View::ConvertPointToScreen(
+        view_->parent() ? view_->parent() : view_, &topleft);
+    *x_left = topleft.x();
+    *y_top  = topleft.y();
+  } else {
+    return E_FAIL;
+  }
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::accNavigate(
+    LONG nav_dir, VARIANT start, VARIANT* end) {
+  if (start.vt != VT_I4 || !end)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  switch (nav_dir) {
+    case NAVDIR_FIRSTCHILD:
+    case NAVDIR_LASTCHILD: {
+      if (start.lVal != CHILDID_SELF) {
+        // Start of navigation must be on the View itself.
+        return E_INVALIDARG;
+      } else if (!view_->has_children()) {
+        // No children found.
+        return S_FALSE;
+      }
+
+      // Set child_id based on first or last child.
+      int child_id = 0;
+      if (nav_dir == NAVDIR_LASTCHILD)
+        child_id = view_->child_count() - 1;
+
+      View* child = view_->child_at(child_id);
+      end->vt = VT_DISPATCH;
+      end->pdispVal = child->GetNativeViewAccessible();
+      end->pdispVal->AddRef();
+      return S_OK;
+    }
+    case NAVDIR_LEFT:
+    case NAVDIR_UP:
+    case NAVDIR_PREVIOUS:
+    case NAVDIR_RIGHT:
+    case NAVDIR_DOWN:
+    case NAVDIR_NEXT: {
+      // Retrieve parent to access view index and perform bounds checking.
+      View* parent = view_->parent();
+      if (!parent) {
+        return E_FAIL;
+      }
+
+      if (start.lVal == CHILDID_SELF) {
+        int view_index = parent->GetIndexOf(view_);
+        // Check navigation bounds, adjusting for View child indexing (MSAA
+        // child indexing starts with 1, whereas View indexing starts with 0).
+        if (!IsValidNav(nav_dir, view_index, -1,
+                        parent->child_count() - 1)) {
+          // Navigation attempted to go out-of-bounds.
+          end->vt = VT_EMPTY;
+          return S_FALSE;
+        } else {
+          if (IsNavDirNext(nav_dir)) {
+            view_index += 1;
+          } else {
+            view_index -=1;
+          }
+        }
+
+        View* child = parent->child_at(view_index);
+        end->pdispVal = child->GetNativeViewAccessible();
+        end->vt = VT_DISPATCH;
+        end->pdispVal->AddRef();
+        return S_OK;
+      } else {
+        // Check navigation bounds, adjusting for MSAA child indexing (MSAA
+        // child indexing starts with 1, whereas View indexing starts with 0).
+        if (!IsValidNav(nav_dir, start.lVal, 0, parent->child_count() + 1)) {
+            // Navigation attempted to go out-of-bounds.
+            end->vt = VT_EMPTY;
+            return S_FALSE;
+          } else {
+            if (IsNavDirNext(nav_dir)) {
+              start.lVal += 1;
+            } else {
+              start.lVal -= 1;
+            }
+        }
+
+        HRESULT result = this->get_accChild(start, &end->pdispVal);
+        if (result == S_FALSE) {
+          // Child is a leaf.
+          end->vt = VT_I4;
+          end->lVal = start.lVal;
+        } else if (result == E_INVALIDARG) {
+          return E_INVALIDARG;
+        } else {
+          // Child is not a leaf.
+          end->vt = VT_DISPATCH;
+        }
+      }
+      break;
+    }
+    default:
+      return E_INVALIDARG;
+  }
+  // Navigation performed correctly. Global return for this function, if no
+  // error triggered an escape earlier.
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accChild(VARIANT var_child,
+                                                      IDispatch** disp_child) {
+  if (var_child.vt != VT_I4 || !disp_child)
+    return E_INVALIDARG;
+
+  if (!view_ || !view_->GetWidget())
+    return E_FAIL;
+
+  LONG child_id = V_I4(&var_child);
+
+  if (child_id == CHILDID_SELF) {
+    // Remain with the same dispatch.
+    return S_OK;
+  }
+
+  // If this is a root view, our widget might have child widgets. Include
+  std::vector<Widget*> child_widgets;
+  if (view_->GetWidget()->GetRootView() == view_)
+    PopulateChildWidgetVector(&child_widgets);
+  int child_widget_count = static_cast<int>(child_widgets.size());
+
+  View* child_view = NULL;
+  if (child_id > 0) {
+    // Positive child ids are a 1-based child index, used by clients
+    // that want to enumerate all immediate children.
+    int child_id_as_index = child_id - 1;
+    if (child_id_as_index < view_->child_count()) {
+      child_view = view_->child_at(child_id_as_index);
+    } else if (child_id_as_index < view_->child_count() + child_widget_count) {
+      Widget* child_widget =
+          child_widgets[child_id_as_index - view_->child_count()];
+      child_view = child_widget->GetRootView();
+    }
+  } else {
+    // Negative child ids can be used to map to any descendant.
+    // Check child widget first.
+    for (int i = 0; i < child_widget_count; i++) {
+      Widget* child_widget = child_widgets[i];
+      IAccessible* child_accessible =
+          child_widget->GetRootView()->GetNativeViewAccessible();
+      HRESULT result = child_accessible->get_accChild(var_child, disp_child);
+      if (result == S_OK)
+        return result;
+    }
+
+    // We map child ids to a view storage id that can refer to a
+    // specific view (if that view still exists).
+    int view_storage_id_index =
+        base::win::kFirstViewsAccessibilityId - child_id;
+    if (view_storage_id_index >= 0 &&
+        view_storage_id_index < kMaxViewStorageIds) {
+      int view_storage_id = view_storage_ids_[view_storage_id_index];
+      ViewStorage* view_storage = ViewStorage::GetInstance();
+      child_view = view_storage->RetrieveView(view_storage_id);
+    } else {
+      *disp_child = AccessibleWebViewRegistry::GetInstance()->
+          GetAccessibleFromWebView(view_, child_id);
+      if (*disp_child)
+        return S_OK;
+    }
+  }
+
+  if (!child_view) {
+    // No child found.
+    *disp_child = NULL;
+    return E_FAIL;
+  }
+
+  *disp_child = child_view->GetNativeViewAccessible();
+  if (*disp_child) {
+    (*disp_child)->AddRef();
+    return S_OK;
+  }
+
+  return E_FAIL;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accChildCount(LONG* child_count) {
+  if (!child_count)
+    return E_INVALIDARG;
+
+  if (!view_ || !view_->GetWidget())
+    return E_FAIL;
+
+  *child_count = view_->child_count();
+
+  // If this is a root view, our widget might have child widgets. Include
+  // them, too.
+  if (view_->GetWidget()->GetRootView() == view_) {
+    std::vector<Widget*> child_widgets;
+    PopulateChildWidgetVector(&child_widgets);
+    *child_count += child_widgets.size();
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accDefaultAction(
+    VARIANT var_id, BSTR* def_action) {
+  if (!IsValidId(var_id) || !def_action)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  base::string16 temp_action = state.default_action;
+
+  if (!temp_action.empty()) {
+    *def_action = SysAllocString(temp_action.c_str());
+  } else {
+    return S_FALSE;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accDescription(
+    VARIANT var_id, BSTR* desc) {
+  if (!IsValidId(var_id) || !desc)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  base::string16 temp_desc;
+
+  view_->GetTooltipText(gfx::Point(), &temp_desc);
+  if (!temp_desc.empty()) {
+    *desc = SysAllocString(temp_desc.c_str());
+  } else {
+    return S_FALSE;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accFocus(VARIANT* focus_child) {
+  if (!focus_child)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  FocusManager* focus_manager = view_->GetFocusManager();
+  View* focus = focus_manager ? focus_manager->GetFocusedView() : NULL;
+  if (focus == view_) {
+    // This view has focus.
+    focus_child->vt = VT_I4;
+    focus_child->lVal = CHILDID_SELF;
+  } else if (focus && view_->Contains(focus)) {
+    // Return the child object that has the keyboard focus.
+    focus_child->vt = VT_DISPATCH;
+    focus_child->pdispVal = focus->GetNativeViewAccessible();
+    focus_child->pdispVal->AddRef();
+    return S_OK;
+  } else {
+    // Neither this object nor any of its children has the keyboard focus.
+    focus_child->vt = VT_EMPTY;
+  }
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accKeyboardShortcut(
+    VARIANT var_id, BSTR* acc_key) {
+  if (!IsValidId(var_id) || !acc_key)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  base::string16 temp_key = state.keyboard_shortcut;
+
+  if (!temp_key.empty()) {
+    *acc_key = SysAllocString(temp_key.c_str());
+  } else {
+    return S_FALSE;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accName(
+    VARIANT var_id, BSTR* name) {
+  if (!IsValidId(var_id) || !name)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  // Retrieve the current view's name.
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  base::string16 temp_name = state.name;
+  if (!temp_name.empty()) {
+    // Return name retrieved.
+    *name = SysAllocString(temp_name.c_str());
+  } else {
+    // If view has no name, return S_FALSE.
+    return S_FALSE;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accParent(
+    IDispatch** disp_parent) {
+  if (!disp_parent)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  *disp_parent = NULL;
+  View* parent_view = view_->parent();
+
+  if (!parent_view) {
+    HWND hwnd = HWNDForView(view_);
+    if (!hwnd)
+      return S_FALSE;
+
+    return ::AccessibleObjectFromWindow(
+        hwnd, OBJID_WINDOW, IID_IAccessible,
+        reinterpret_cast<void**>(disp_parent));
+  }
+
+  *disp_parent = parent_view->GetNativeViewAccessible();
+  (*disp_parent)->AddRef();
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accRole(
+    VARIANT var_id, VARIANT* role) {
+  if (!IsValidId(var_id) || !role)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  role->vt = VT_I4;
+  role->lVal = MSAARole(state.role);
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accState(
+    VARIANT var_id, VARIANT* state) {
+  // This returns MSAA states. See also the IAccessible2 interface
+  // get_states().
+
+  if (!IsValidId(var_id) || !state)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  state->vt = VT_I4;
+
+  // Retrieve all currently applicable states of the parent.
+  SetState(state, view_);
+
+  // Make sure that state is not empty, and has the proper type.
+  if (state->vt == VT_EMPTY)
+    return E_FAIL;
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accValue(VARIANT var_id,
+                                                      BSTR* value) {
+  if (!IsValidId(var_id) || !value)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  // Retrieve the current view's value.
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  base::string16 temp_value = state.value;
+
+  if (!temp_value.empty()) {
+    // Return value retrieved.
+    *value = SysAllocString(temp_value.c_str());
+  } else {
+    // If view has no value, fall back into the default implementation.
+    *value = NULL;
+    return E_NOTIMPL;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::put_accValue(VARIANT var_id,
+                                                      BSTR new_value) {
+  if (!IsValidId(var_id) || !new_value)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  // Return an error if the view can't set the value.
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  if (state.set_value_callback.is_null())
+    return E_FAIL;
+
+  state.set_value_callback.Run(new_value);
+  return S_OK;
+}
+
+// IAccessible functions not supported.
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accSelection(VARIANT* selected) {
+  if (selected)
+    selected->vt = VT_EMPTY;
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::accSelect(
+    LONG flagsSelect, VARIANT var_id) {
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accHelp(
+    VARIANT var_id, BSTR* help) {
+  if (!IsValidId(var_id) || !help)
+    return E_INVALIDARG;
+
+  if (!view_)
+    return E_FAIL;
+
+  base::string16 temp = base::UTF8ToUTF16(view_->GetClassName());
+  *help = SysAllocString(temp.c_str());
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_accHelpTopic(
+    BSTR* help_file, VARIANT var_id, LONG* topic_id) {
+  if (help_file) {
+    *help_file = NULL;
+  }
+  if (topic_id) {
+    *topic_id = static_cast<LONG>(-1);
+  }
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::put_accName(
+    VARIANT var_id, BSTR put_name) {
+  // Deprecated.
+  return E_NOTIMPL;
+}
+
+//
+// IAccessible2
+//
+
+STDMETHODIMP NativeViewAccessibilityWin::role(LONG* role) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!role)
+    return E_INVALIDARG;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  *role = MSAARole(state.role);
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_states(AccessibleStates* states) {
+  // This returns IAccessible2 states, which supplement MSAA states.
+  // See also the MSAA interface get_accState.
+
+  if (!view_)
+    return E_FAIL;
+
+  if (!states)
+    return E_INVALIDARG;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+
+  // There are only a couple of states we need to support
+  // in IAccessible2. If any more are added, we may want to
+  // add a helper function like MSAAState.
+  *states = IA2_STATE_OPAQUE;
+  if (state.HasStateFlag(ui::AX_STATE_EDITABLE))
+    *states |= IA2_STATE_EDITABLE;
+
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_uniqueID(LONG* unique_id) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!unique_id)
+    return E_INVALIDARG;
+
+  *unique_id = unique_id_;
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_windowHandle(HWND* window_handle) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!window_handle)
+    return E_INVALIDARG;
+
+  *window_handle = HWNDForView(view_);
+  return *window_handle ? S_OK : S_FALSE;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_relationTargetsOfType(
+    BSTR type_bstr,
+    long max_targets,
+    IUnknown ***targets,
+    long *n_targets) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!targets || !n_targets)
+    return E_INVALIDARG;
+
+  *n_targets = 0;
+  *targets = NULL;
+
+  // Only respond to requests for relations of type "alerts" on the
+  // root view.
+  base::string16 type(type_bstr);
+  if (type != L"alerts" || view_->parent())
+    return S_FALSE;
+
+  // Collect all of the alert views that are still valid.
+  std::vector<View*> alert_views;
+  ViewStorage* view_storage = ViewStorage::GetInstance();
+  for (size_t i = 0; i < alert_target_view_storage_ids_.size(); ++i) {
+    int view_storage_id = alert_target_view_storage_ids_[i];
+    View* view = view_storage->RetrieveView(view_storage_id);
+    if (!view || !view_->Contains(view))
+      continue;
+    alert_views.push_back(view);
+  }
+
+  long count = alert_views.size();
+  if (count == 0)
+    return S_FALSE;
+
+  // Don't return more targets than max_targets - but note that the caller
+  // is allowed to specify max_targets=0 to mean no limit.
+  if (max_targets > 0 && count > max_targets)
+    count = max_targets;
+
+  // Return the number of targets.
+  *n_targets = count;
+
+  // Allocate COM memory for the result array and populate it.
+  *targets = static_cast<IUnknown**>(
+      CoTaskMemAlloc(count * sizeof(IUnknown*)));
+  for (long i = 0; i < count; ++i) {
+    (*targets)[i] = alert_views[i]->GetNativeViewAccessible();
+    (*targets)[i]->AddRef();
+  }
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_attributes(BSTR* attributes) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!attributes)
+    return E_INVALIDARG;
+
+  base::string16 attributes_str;
+
+  // Text fields need to report the attribute "text-model:a1" to instruct
+  // screen readers to use IAccessible2 APIs to handle text editing in this
+  // object (as opposed to treating it like a native Windows text box).
+  // The text-model:a1 attribute is documented here:
+  // http://www.linuxfoundation.org/collaborate/workgroups/accessibility/ia2/ia2_implementation_guide
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  if (state.role == ui::AX_ROLE_TEXT_FIELD) {
+    attributes_str = L"text-model:a1;";
+  }
+
+  *attributes = SysAllocString(attributes_str.c_str());
+  DCHECK(*attributes);
+  return S_OK;
+}
+
+//
+// IAccessibleText
+//
+
+STDMETHODIMP NativeViewAccessibilityWin::get_nCharacters(LONG* n_characters) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!n_characters)
+    return E_INVALIDARG;
+
+  base::string16 text = TextForIAccessibleText();
+  *n_characters = static_cast<LONG>(text.size());
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_caretOffset(LONG* offset) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!offset)
+    return E_INVALIDARG;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  *offset = static_cast<LONG>(state.selection_end);
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_nSelections(LONG* n_selections) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!n_selections)
+    return E_INVALIDARG;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  if (state.selection_start != state.selection_end)
+    *n_selections = 1;
+  else
+    *n_selections = 0;
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_selection(LONG selection_index,
+                                                      LONG* start_offset,
+                                                      LONG* end_offset) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!start_offset || !end_offset || selection_index != 0)
+    return E_INVALIDARG;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  *start_offset = static_cast<LONG>(state.selection_start);
+  *end_offset = static_cast<LONG>(state.selection_end);
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_text(LONG start_offset,
+                                                  LONG end_offset,
+                                                  BSTR* text) {
+  if (!view_)
+    return E_FAIL;
+
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  base::string16 text_str = TextForIAccessibleText();
+  LONG len = static_cast<LONG>(text_str.size());
+
+  if (start_offset == IA2_TEXT_OFFSET_LENGTH) {
+    start_offset = len;
+  } else if (start_offset == IA2_TEXT_OFFSET_CARET) {
+    start_offset = static_cast<LONG>(state.selection_end);
+  }
+  if (end_offset == IA2_TEXT_OFFSET_LENGTH) {
+    end_offset = static_cast<LONG>(text_str.size());
+  } else if (end_offset == IA2_TEXT_OFFSET_CARET) {
+    end_offset = static_cast<LONG>(state.selection_end);
+  }
+
+  // The spec allows the arguments to be reversed.
+  if (start_offset > end_offset) {
+    LONG tmp = start_offset;
+    start_offset = end_offset;
+    end_offset = tmp;
+  }
+
+  // The spec does not allow the start or end offsets to be out or range;
+  // we must return an error if so.
+  if (start_offset < 0)
+    return E_INVALIDARG;
+  if (end_offset > len)
+    return E_INVALIDARG;
+
+  base::string16 substr =
+      text_str.substr(start_offset, end_offset - start_offset);
+  if (substr.empty())
+    return S_FALSE;
+
+  *text = SysAllocString(substr.c_str());
+  DCHECK(*text);
+  return S_OK;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_textAtOffset(
+    LONG offset,
+    enum IA2TextBoundaryType boundary_type,
+    LONG* start_offset, LONG* end_offset,
+    BSTR* text) {
+  if (!start_offset || !end_offset || !text)
+    return E_INVALIDARG;
+
+  // The IAccessible2 spec says we don't have to implement the "sentence"
+  // boundary type, we can just let the screenreader handle it.
+  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
+    *start_offset = 0;
+    *end_offset = 0;
+    *text = NULL;
+    return S_FALSE;
+  }
+
+  const base::string16& text_str = TextForIAccessibleText();
+
+  *start_offset = FindBoundary(
+      text_str, boundary_type, offset, ui::BACKWARDS_DIRECTION);
+  *end_offset = FindBoundary(
+      text_str, boundary_type, offset, ui::FORWARDS_DIRECTION);
+  return get_text(*start_offset, *end_offset, text);
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_textBeforeOffset(
+    LONG offset,
+    enum IA2TextBoundaryType boundary_type,
+    LONG* start_offset, LONG* end_offset,
+    BSTR* text) {
+  if (!start_offset || !end_offset || !text)
+    return E_INVALIDARG;
+
+  // The IAccessible2 spec says we don't have to implement the "sentence"
+  // boundary type, we can just let the screenreader handle it.
+  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
+    *start_offset = 0;
+    *end_offset = 0;
+    *text = NULL;
+    return S_FALSE;
+  }
+
+  const base::string16& text_str = TextForIAccessibleText();
+
+  *start_offset = FindBoundary(
+      text_str, boundary_type, offset, ui::BACKWARDS_DIRECTION);
+  *end_offset = offset;
+  return get_text(*start_offset, *end_offset, text);
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_textAfterOffset(
+    LONG offset,
+    enum IA2TextBoundaryType boundary_type,
+    LONG* start_offset, LONG* end_offset,
+    BSTR* text) {
+  if (!start_offset || !end_offset || !text)
+    return E_INVALIDARG;
+
+  // The IAccessible2 spec says we don't have to implement the "sentence"
+  // boundary type, we can just let the screenreader handle it.
+  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
+    *start_offset = 0;
+    *end_offset = 0;
+    *text = NULL;
+    return S_FALSE;
+  }
+
+  const base::string16& text_str = TextForIAccessibleText();
+
+  *start_offset = offset;
+  *end_offset = FindBoundary(
+      text_str, boundary_type, offset, ui::FORWARDS_DIRECTION);
+  return get_text(*start_offset, *end_offset, text);
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::get_offsetAtPoint(
+    LONG x, LONG y, enum IA2CoordinateType coord_type, LONG* offset) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!offset)
+    return E_INVALIDARG;
+
+  // We don't support this method, but we have to return something
+  // rather than E_NOTIMPL or screen readers will complain.
+  *offset = 0;
+  return S_OK;
+}
+
+//
+// IServiceProvider methods.
+//
+
+STDMETHODIMP NativeViewAccessibilityWin::QueryService(
+    REFGUID guidService, REFIID riid, void** object) {
+  if (!view_)
+    return E_FAIL;
+
+  if (riid == IID_IAccessible2 || riid == IID_IAccessible2_2)
+    AccessibleWebViewRegistry::GetInstance()->EnableIAccessible2Support();
+
+  if (guidService == IID_IAccessible ||
+      guidService == IID_IAccessible2 ||
+      guidService == IID_IAccessible2_2 ||
+      guidService == IID_IAccessibleText)  {
+    return QueryInterface(riid, object);
+  }
+
+  // We only support the IAccessibleEx interface on Windows 8 and above. This
+  // is needed for the On screen Keyboard to show up in metro mode, when the
+  // user taps an editable region in the window.
+  // All methods in the IAccessibleEx interface are unimplemented.
+  if (riid == IID_IAccessibleEx &&
+      base::win::GetVersion() >= base::win::VERSION_WIN8) {
+    return QueryInterface(riid, object);
+  }
+
+  *object = NULL;
+  return E_FAIL;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::GetPatternProvider(
+    PATTERNID id, IUnknown** provider) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!provider)
+    return E_INVALIDARG;
+
+  DVLOG(1) << "In Function: "
+           << __FUNCTION__
+           << " for pattern id: "
+           << id;
+  if (id == UIA_ValuePatternId || id == UIA_TextPatternId) {
+    ui::AXViewState state;
+    view_->GetAccessibleState(&state);
+    long role = MSAARole(state.role);
+
+    if (role == ROLE_SYSTEM_TEXT) {
+      DVLOG(1) << "Returning UIA text provider";
+      base::win::UIATextProvider::CreateTextProvider(
+          state.value, true, provider);
+      return S_OK;
+    }
+  }
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP NativeViewAccessibilityWin::GetPropertyValue(PROPERTYID id,
+                                                          VARIANT* ret) {
+  if (!view_)
+    return E_FAIL;
+
+  if (!ret)
+    return E_INVALIDARG;
+
+  DVLOG(1) << "In Function: "
+           << __FUNCTION__
+           << " for property id: "
+           << id;
+  if (id == UIA_ControlTypePropertyId) {
+    ui::AXViewState state;
+    view_->GetAccessibleState(&state);
+    long role = MSAARole(state.role);
+    if (role == ROLE_SYSTEM_TEXT) {
+      V_VT(ret) = VT_I4;
+      ret->lVal = UIA_EditControlTypeId;
+      DVLOG(1) << "Returning Edit control type";
+    } else {
+      DVLOG(1) << "Returning empty control type";
+      V_VT(ret) = VT_EMPTY;
+    }
+  } else {
+    V_VT(ret) = VT_EMPTY;
+  }
+  return S_OK;
+}
+
+//
+// Static methods.
+//
+
+void NativeViewAccessibility::RegisterWebView(View* web_view) {
+  AccessibleWebViewRegistry::GetInstance()->RegisterWebView(web_view);
+}
+
+void NativeViewAccessibility::UnregisterWebView(View* web_view) {
+  AccessibleWebViewRegistry::GetInstance()->UnregisterWebView(web_view);
+}
+
+int32 NativeViewAccessibilityWin::MSAAEvent(ui::AXEvent event) {
+  switch (event) {
+    case ui::AX_EVENT_ALERT:
+      return EVENT_SYSTEM_ALERT;
+    case ui::AX_EVENT_FOCUS:
+      return EVENT_OBJECT_FOCUS;
+    case ui::AX_EVENT_MENU_START:
+      return EVENT_SYSTEM_MENUSTART;
+    case ui::AX_EVENT_MENU_END:
+      return EVENT_SYSTEM_MENUEND;
+    case ui::AX_EVENT_MENU_POPUP_START:
+      return EVENT_SYSTEM_MENUPOPUPSTART;
+    case ui::AX_EVENT_MENU_POPUP_END:
+      return EVENT_SYSTEM_MENUPOPUPEND;
+    case ui::AX_EVENT_SELECTION:
+      return EVENT_OBJECT_SELECTION;
+    case ui::AX_EVENT_SELECTION_ADD:
+      return EVENT_OBJECT_SELECTIONADD;
+    case ui::AX_EVENT_SELECTION_REMOVE:
+      return EVENT_OBJECT_SELECTIONREMOVE;
+    case ui::AX_EVENT_TEXT_CHANGED:
+      return EVENT_OBJECT_NAMECHANGE;
+    case ui::AX_EVENT_TEXT_SELECTION_CHANGED:
+      return IA2_EVENT_TEXT_CARET_MOVED;
+    case ui::AX_EVENT_VALUE_CHANGED:
+      return EVENT_OBJECT_VALUECHANGE;
+    default:
+      // Not supported or invalid event.
+      NOTREACHED();
+      return -1;
+  }
+}
+
+int32 NativeViewAccessibilityWin::MSAARole(ui::AXRole role) {
+  switch (role) {
+    case ui::AX_ROLE_ALERT:
+      return ROLE_SYSTEM_ALERT;
+    case ui::AX_ROLE_APPLICATION:
+      return ROLE_SYSTEM_APPLICATION;
+    case ui::AX_ROLE_BUTTON_DROP_DOWN:
+      return ROLE_SYSTEM_BUTTONDROPDOWN;
+    case ui::AX_ROLE_POP_UP_BUTTON:
+      return ROLE_SYSTEM_BUTTONMENU;
+    case ui::AX_ROLE_CHECK_BOX:
+      return ROLE_SYSTEM_CHECKBUTTON;
+    case ui::AX_ROLE_COMBO_BOX:
+      return ROLE_SYSTEM_COMBOBOX;
+    case ui::AX_ROLE_DIALOG:
+      return ROLE_SYSTEM_DIALOG;
+    case ui::AX_ROLE_GROUP:
+      return ROLE_SYSTEM_GROUPING;
+    case ui::AX_ROLE_IMAGE:
+      return ROLE_SYSTEM_GRAPHIC;
+    case ui::AX_ROLE_LINK:
+      return ROLE_SYSTEM_LINK;
+    case ui::AX_ROLE_LOCATION_BAR:
+      return ROLE_SYSTEM_GROUPING;
+    case ui::AX_ROLE_MENU_BAR:
+      return ROLE_SYSTEM_MENUBAR;
+    case ui::AX_ROLE_MENU_ITEM:
+      return ROLE_SYSTEM_MENUITEM;
+    case ui::AX_ROLE_MENU_LIST_POPUP:
+      return ROLE_SYSTEM_MENUPOPUP;
+    case ui::AX_ROLE_TREE:
+      return ROLE_SYSTEM_OUTLINE;
+    case ui::AX_ROLE_TREE_ITEM:
+      return ROLE_SYSTEM_OUTLINEITEM;
+    case ui::AX_ROLE_TAB:
+      return ROLE_SYSTEM_PAGETAB;
+    case ui::AX_ROLE_TAB_LIST:
+      return ROLE_SYSTEM_PAGETABLIST;
+    case ui::AX_ROLE_PANE:
+      return ROLE_SYSTEM_PANE;
+    case ui::AX_ROLE_PROGRESS_INDICATOR:
+      return ROLE_SYSTEM_PROGRESSBAR;
+    case ui::AX_ROLE_BUTTON:
+      return ROLE_SYSTEM_PUSHBUTTON;
+    case ui::AX_ROLE_RADIO_BUTTON:
+      return ROLE_SYSTEM_RADIOBUTTON;
+    case ui::AX_ROLE_SCROLL_BAR:
+      return ROLE_SYSTEM_SCROLLBAR;
+    case ui::AX_ROLE_SPLITTER:
+      return ROLE_SYSTEM_SEPARATOR;
+    case ui::AX_ROLE_SLIDER:
+      return ROLE_SYSTEM_SLIDER;
+    case ui::AX_ROLE_STATIC_TEXT:
+      return ROLE_SYSTEM_STATICTEXT;
+    case ui::AX_ROLE_TEXT_FIELD:
+      return ROLE_SYSTEM_TEXT;
+    case ui::AX_ROLE_TITLE_BAR:
+      return ROLE_SYSTEM_TITLEBAR;
+    case ui::AX_ROLE_TOOLBAR:
+      return ROLE_SYSTEM_TOOLBAR;
+    case ui::AX_ROLE_WEB_VIEW:
+      return ROLE_SYSTEM_GROUPING;
+    case ui::AX_ROLE_WINDOW:
+      return ROLE_SYSTEM_WINDOW;
+    case ui::AX_ROLE_CLIENT:
+    default:
+      // This is the default role for MSAA.
+      return ROLE_SYSTEM_CLIENT;
+  }
+}
+
+int32 NativeViewAccessibilityWin::MSAAState(const ui::AXViewState& state) {
+  // This maps MSAA states for get_accState(). See also the IAccessible2
+  // interface get_states().
+
+  int32 msaa_state = 0;
+  if (state.HasStateFlag(ui::AX_STATE_CHECKED))
+    msaa_state |= STATE_SYSTEM_CHECKED;
+  if (state.HasStateFlag(ui::AX_STATE_COLLAPSED))
+    msaa_state |= STATE_SYSTEM_COLLAPSED;
+  if (state.HasStateFlag(ui::AX_STATE_DEFAULT))
+    msaa_state |= STATE_SYSTEM_DEFAULT;
+  if (state.HasStateFlag(ui::AX_STATE_EXPANDED))
+    msaa_state |= STATE_SYSTEM_EXPANDED;
+  if (state.HasStateFlag(ui::AX_STATE_HASPOPUP))
+    msaa_state |= STATE_SYSTEM_HASPOPUP;
+  if (state.HasStateFlag(ui::AX_STATE_HOVERED))
+    msaa_state |= STATE_SYSTEM_HOTTRACKED;
+  if (state.HasStateFlag(ui::AX_STATE_INVISIBLE))
+    msaa_state |= STATE_SYSTEM_INVISIBLE;
+  if (state.HasStateFlag(ui::AX_STATE_LINKED))
+    msaa_state |= STATE_SYSTEM_LINKED;
+  if (state.HasStateFlag(ui::AX_STATE_OFFSCREEN))
+    msaa_state |= STATE_SYSTEM_OFFSCREEN;
+  if (state.HasStateFlag(ui::AX_STATE_PRESSED))
+    msaa_state |= STATE_SYSTEM_PRESSED;
+  if (state.HasStateFlag(ui::AX_STATE_PROTECTED))
+    msaa_state |= STATE_SYSTEM_PROTECTED;
+  if (state.HasStateFlag(ui::AX_STATE_READ_ONLY))
+    msaa_state |= STATE_SYSTEM_READONLY;
+  if (state.HasStateFlag(ui::AX_STATE_SELECTABLE))
+    msaa_state |= STATE_SYSTEM_SELECTABLE;
+  if (state.HasStateFlag(ui::AX_STATE_SELECTED))
+    msaa_state |= STATE_SYSTEM_SELECTED;
+  if (state.HasStateFlag(ui::AX_STATE_FOCUSED))
+    msaa_state |= STATE_SYSTEM_FOCUSED;
+  if (state.HasStateFlag(ui::AX_STATE_DISABLED))
+    msaa_state |= STATE_SYSTEM_UNAVAILABLE;
+  return msaa_state;
+}
+
+//
+// Private methods.
+//
+
+bool NativeViewAccessibilityWin::IsNavDirNext(int nav_dir) const {
+  return (nav_dir == NAVDIR_RIGHT ||
+          nav_dir == NAVDIR_DOWN ||
+          nav_dir == NAVDIR_NEXT);
+}
+
+bool NativeViewAccessibilityWin::IsValidNav(
+    int nav_dir, int start_id, int lower_bound, int upper_bound) const {
+  if (IsNavDirNext(nav_dir)) {
+    if ((start_id + 1) > upper_bound) {
+      return false;
+    }
+  } else {
+    if ((start_id - 1) <= lower_bound) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool NativeViewAccessibilityWin::IsValidId(const VARIANT& child) const {
+  // View accessibility returns an IAccessible for each view so we only support
+  // the CHILDID_SELF id.
+  return (VT_I4 == child.vt) && (CHILDID_SELF == child.lVal);
+}
+
+void NativeViewAccessibilityWin::SetState(
+    VARIANT* msaa_state, View* view) {
+  // Ensure the output param is initialized to zero.
+  msaa_state->lVal = 0;
+
+  // Default state; all views can have accessibility focus.
+  msaa_state->lVal |= STATE_SYSTEM_FOCUSABLE;
+
+  if (!view)
+    return;
+
+  if (!view->enabled())
+    msaa_state->lVal |= STATE_SYSTEM_UNAVAILABLE;
+  if (!view->visible())
+    msaa_state->lVal |= STATE_SYSTEM_INVISIBLE;
+  if (!strcmp(view->GetClassName(), CustomButton::kViewClassName)) {
+    CustomButton* button = static_cast<CustomButton*>(view);
+    if (button->IsHotTracked())
+      msaa_state->lVal |= STATE_SYSTEM_HOTTRACKED;
+  }
+  if (view->HasFocus())
+    msaa_state->lVal |= STATE_SYSTEM_FOCUSED;
+
+  // Add on any view-specific states.
+  ui::AXViewState view_state;
+  view->GetAccessibleState(&view_state);
+  msaa_state->lVal |= MSAAState(view_state);
+}
+
+base::string16 NativeViewAccessibilityWin::TextForIAccessibleText() {
+  ui::AXViewState state;
+  view_->GetAccessibleState(&state);
+  if (state.role == ui::AX_ROLE_TEXT_FIELD)
+    return state.value;
+  else
+    return state.name;
+}
+
+void NativeViewAccessibilityWin::HandleSpecialTextOffset(
+    const base::string16& text, LONG* offset) {
+  if (*offset == IA2_TEXT_OFFSET_LENGTH) {
+    *offset = static_cast<LONG>(text.size());
+  } else if (*offset == IA2_TEXT_OFFSET_CARET) {
+    get_caretOffset(offset);
+  }
+}
+
+ui::TextBoundaryType NativeViewAccessibilityWin::IA2TextBoundaryToTextBoundary(
+    IA2TextBoundaryType ia2_boundary) {
+  switch(ia2_boundary) {
+    case IA2_TEXT_BOUNDARY_CHAR: return ui::CHAR_BOUNDARY;
+    case IA2_TEXT_BOUNDARY_WORD: return ui::WORD_BOUNDARY;
+    case IA2_TEXT_BOUNDARY_LINE: return ui::LINE_BOUNDARY;
+    case IA2_TEXT_BOUNDARY_SENTENCE: return ui::SENTENCE_BOUNDARY;
+    case IA2_TEXT_BOUNDARY_PARAGRAPH: return ui::PARAGRAPH_BOUNDARY;
+    case IA2_TEXT_BOUNDARY_ALL: return ui::ALL_BOUNDARY;
+    default:
+      NOTREACHED();
+      return ui::CHAR_BOUNDARY;
+  }
+}
+
+LONG NativeViewAccessibilityWin::FindBoundary(
+    const base::string16& text,
+    IA2TextBoundaryType ia2_boundary,
+    LONG start_offset,
+    ui::TextBoundaryDirection direction) {
+  HandleSpecialTextOffset(text, &start_offset);
+  ui::TextBoundaryType boundary = IA2TextBoundaryToTextBoundary(ia2_boundary);
+  std::vector<int32> line_breaks;
+  return ui::FindAccessibleTextBoundary(
+      text, line_breaks, boundary, start_offset, direction);
+}
+
+void NativeViewAccessibilityWin::PopulateChildWidgetVector(
+    std::vector<Widget*>* result_child_widgets) {
+  const Widget* widget = view()->GetWidget();
+  if (!widget)
+    return;
+
+  std::set<Widget*> child_widgets;
+  Widget::GetAllOwnedWidgets(widget->GetNativeView(), &child_widgets);
+  for (std::set<Widget*>::const_iterator iter = child_widgets.begin();
+           iter != child_widgets.end(); ++iter) {
+    Widget* child_widget = *iter;
+    DCHECK_NE(widget, child_widget);
+
+    if (!child_widget->IsVisible())
+      continue;
+
+    if (widget->GetNativeWindowProperty(kWidgetNativeViewHostKey))
+      continue;
+
+    result_child_widgets->push_back(child_widget);
+  }
+}
+
+void NativeViewAccessibilityWin::AddAlertTarget() {
+  ViewStorage* view_storage = ViewStorage::GetInstance();
+  for (size_t i = 0; i < alert_target_view_storage_ids_.size(); ++i) {
+    int view_storage_id = alert_target_view_storage_ids_[i];
+    View* view = view_storage->RetrieveView(view_storage_id);
+    if (view == view_)
+      return;
+  }
+  int view_storage_id = view_storage->CreateStorageID();
+  view_storage->StoreView(view_storage_id, view_);
+  alert_target_view_storage_ids_.push_back(view_storage_id);
+}
+
+void NativeViewAccessibilityWin::RemoveAlertTarget() {
+  ViewStorage* view_storage = ViewStorage::GetInstance();
+  size_t i = 0;
+  while (i < alert_target_view_storage_ids_.size()) {
+    int view_storage_id = alert_target_view_storage_ids_[i];
+    View* view = view_storage->RetrieveView(view_storage_id);
+    if (view == NULL || view == view_) {
+      alert_target_view_storage_ids_.erase(
+          alert_target_view_storage_ids_.begin() + i);
+    } else {
+      ++i;
+    }
+  }
 }
 
 }  // namespace views