1 files changed, 816 insertions, 0 deletions

diff --git a/accessible/ipc/win/ProxyAccessible.cpp b/accessible/ipc/win/ProxyAccessible.cpp
new file mode 100644
index 0000000000..bcf388e603
--- /dev/null
+++ b/accessible/ipc/win/ProxyAccessible.cpp
@@ -0,0 +1,816 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Accessible2.h"
+#include "ProxyAccessible.h"
+#include "ia2AccessibleRelation.h"
+#include "ia2AccessibleValue.h"
+#include "IGeckoCustom.h"
+#include "mozilla/a11y/DocAccessibleParent.h"
+#include "DocAccessible.h"
+#include "mozilla/a11y/DocManager.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/BrowserParent.h"
+#include "mozilla/Unused.h"
+#include "mozilla/a11y/Platform.h"
+#include "RelationType.h"
+#include "mozilla/a11y/Role.h"
+
+#include <comutil.h>
+
+static const VARIANT kChildIdSelf = {{{VT_I4}}};
+
+namespace mozilla {
+namespace a11y {
+
+bool ProxyAccessible::GetCOMInterface(void** aOutAccessible) const {
+  if (!aOutAccessible) {
+    return false;
+  }
+
+  if (!mCOMProxy && mSafeToRecurse) {
+    // See if we can lazily obtain a COM proxy
+    AccessibleWrap* wrap = WrapperFor(this);
+    bool isDefunct = false;
+    ProxyAccessible* thisPtr = const_cast<ProxyAccessible*>(this);
+    // NB: Don't pass CHILDID_SELF here, use the absolute MSAA ID. Otherwise
+    // GetIAccessibleFor will recurse into this function and we will just
+    // overflow the stack.
+    VARIANT realId = {{{VT_I4}}};
+    realId.ulVal = wrap->GetExistingID();
+    MOZ_DIAGNOSTIC_ASSERT(realId.ulVal != CHILDID_SELF);
+    thisPtr->mCOMProxy = wrap->GetIAccessibleFor(realId, &isDefunct);
+  }
+
+  RefPtr<IAccessible> addRefed = mCOMProxy;
+  addRefed.forget(aOutAccessible);
+  return !!mCOMProxy;
+}
+
+/**
+ * Specializations of this template map an IAccessible type to its IID
+ */
+template <typename Interface>
+struct InterfaceIID {};
+
+template <>
+struct InterfaceIID<IAccessibleValue> {
+  static REFIID Value() { return IID_IAccessibleValue; }
+};
+
+template <>
+struct InterfaceIID<IAccessibleText> {
+  static REFIID Value() { return IID_IAccessibleText; }
+};
+
+template <>
+struct InterfaceIID<IAccessibleHyperlink> {
+  static REFIID Value() { return IID_IAccessibleHyperlink; }
+};
+
+template <>
+struct InterfaceIID<IGeckoCustom> {
+  static REFIID Value() { return IID_IGeckoCustom; }
+};
+
+template <>
+struct InterfaceIID<IAccessible2_2> {
+  static REFIID Value() { return IID_IAccessible2_2; }
+};
+
+/**
+ * Get the COM proxy for this proxy accessible and QueryInterface it with the
+ * correct IID
+ */
+template <typename Interface>
+static already_AddRefed<Interface> QueryInterface(
+    const ProxyAccessible* aProxy) {
+  RefPtr<IAccessible> acc;
+  if (!aProxy->GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return nullptr;
+  }
+
+  RefPtr<Interface> acc2;
+  if (FAILED(acc->QueryInterface(InterfaceIID<Interface>::Value(),
+                                 (void**)getter_AddRefs(acc2)))) {
+    return nullptr;
+  }
+
+  return acc2.forget();
+}
+
+static ProxyAccessible* GetProxyFor(DocAccessibleParent* aDoc,
+                                    IUnknown* aCOMProxy) {
+  RefPtr<IGeckoCustom> custom;
+  if (FAILED(aCOMProxy->QueryInterface(IID_IGeckoCustom,
+                                       (void**)getter_AddRefs(custom)))) {
+    return nullptr;
+  }
+
+  uint64_t id;
+  if (FAILED(custom->get_ID(&id))) {
+    return nullptr;
+  }
+
+  return aDoc->GetAccessible(id);
+}
+
+uint32_t ProxyAccessible::Name(nsString& aName) const {
+  /* The return values here exist only to match behvaiour required
+   * by the header declaration of this function. On Mac, we'd like
+   * to return the associated ENameValueFlag, but we don't have
+   * access to that here, so we return a dummy eNameOK value instead.
+   */
+  aName.Truncate();
+  RefPtr<IAccessible> acc;
+  if (!GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return eNameOK;
+  }
+
+  BSTR result;
+  HRESULT hr = acc->get_accName(kChildIdSelf, &result);
+  _bstr_t resultWrap(result, false);
+  if (FAILED(hr)) {
+    return eNameOK;
+  }
+  aName = (wchar_t*)resultWrap;
+  return eNameOK;
+}
+
+void ProxyAccessible::Value(nsString& aValue) const {
+  aValue.Truncate();
+  RefPtr<IAccessible> acc;
+  if (!GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return;
+  }
+
+  BSTR result;
+  HRESULT hr = acc->get_accValue(kChildIdSelf, &result);
+  _bstr_t resultWrap(result, false);
+  if (FAILED(hr)) {
+    return;
+  }
+  aValue = (wchar_t*)resultWrap;
+}
+
+double ProxyAccessible::Step() {
+  RefPtr<IGeckoCustom> custom = QueryInterface<IGeckoCustom>(this);
+  if (!custom) {
+    return 0;
+  }
+
+  double increment;
+  HRESULT hr = custom->get_minimumIncrement(&increment);
+  if (FAILED(hr)) {
+    return 0;
+  }
+
+  return increment;
+}
+
+void ProxyAccessible::Description(nsString& aDesc) const {
+  aDesc.Truncate();
+  RefPtr<IAccessible> acc;
+  if (!GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return;
+  }
+
+  BSTR result;
+  HRESULT hr = acc->get_accDescription(kChildIdSelf, &result);
+  _bstr_t resultWrap(result, false);
+  if (FAILED(hr)) {
+    return;
+  }
+  aDesc = (wchar_t*)resultWrap;
+}
+
+uint64_t ProxyAccessible::State() const {
+  RefPtr<IGeckoCustom> custom = QueryInterface<IGeckoCustom>(this);
+  if (!custom) {
+    return 0;
+  }
+
+  uint64_t state;
+  HRESULT hr = custom->get_mozState(&state);
+  if (FAILED(hr)) {
+    return 0;
+  }
+  return state;
+}
+
+nsIntRect ProxyAccessible::Bounds() {
+  nsIntRect rect;
+
+  RefPtr<IAccessible> acc;
+  if (!GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return rect;
+  }
+
+  long left;
+  long top;
+  long width;
+  long height;
+  HRESULT hr = acc->accLocation(&left, &top, &width, &height, kChildIdSelf);
+  if (FAILED(hr)) {
+    return rect;
+  }
+  rect.SetRect(left, top, width, height);
+  return rect;
+}
+
+nsIntRect ProxyAccessible::BoundsInCSSPixels() {
+  RefPtr<IGeckoCustom> custom = QueryInterface<IGeckoCustom>(this);
+  if (!custom) {
+    return nsIntRect();
+  }
+
+  nsIntRect rect;
+  Unused << custom->get_boundsInCSSPixels(&rect.x, &rect.y, &rect.width,
+                                          &rect.height);
+  return rect;
+}
+
+void ProxyAccessible::Language(nsString& aLocale) {
+  aLocale.Truncate();
+
+  RefPtr<IAccessible> acc;
+  if (!GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return;
+  }
+
+  RefPtr<IAccessible2> acc2;
+  if (FAILED(acc->QueryInterface(IID_IAccessible2,
+                                 (void**)getter_AddRefs(acc2)))) {
+    return;
+  }
+
+  IA2Locale locale;
+  HRESULT hr = acc2->get_locale(&locale);
+
+  _bstr_t langWrap(locale.language, false);
+  _bstr_t countryWrap(locale.country, false);
+  _bstr_t variantWrap(locale.variant, false);
+
+  if (FAILED(hr)) {
+    return;
+  }
+
+  // The remaining code should essentially be the inverse of the
+  // ia2Accessible::get_locale conversion to IA2Locale.
+
+  if (!!variantWrap) {
+    aLocale = (wchar_t*)variantWrap;
+    return;
+  }
+
+  if (!!langWrap) {
+    aLocale = (wchar_t*)langWrap;
+    if (!!countryWrap) {
+      aLocale += L"-";
+      aLocale += (wchar_t*)countryWrap;
+    }
+  }
+}
+
+static bool IsEscapedChar(const wchar_t c) {
+  return c == L'\\' || c == L':' || c == ',' || c == '=' || c == ';';
+}
+
+static bool ConvertBSTRAttributesToArray(const nsAString& aStr,
+                                         nsTArray<Attribute>* aAttrs) {
+  if (!aAttrs) {
+    return false;
+  }
+
+  enum { eName = 0, eValue = 1, eNumStates } state;
+  nsAutoString tokens[eNumStates];
+  auto itr = aStr.BeginReading(), end = aStr.EndReading();
+
+  state = eName;
+  while (itr != end) {
+    switch (*itr) {
+      case L'\\':
+        // Skip the backslash so that we're looking at the escaped char
+        ++itr;
+        if (itr == end || !IsEscapedChar(*itr)) {
+          // Invalid state
+          return false;
+        }
+        break;
+      case L':':
+        if (state != eName) {
+          // Bad, should be looking at name
+          return false;
+        }
+        state = eValue;
+        ++itr;
+        continue;
+      case L';':
+        if (state != eValue) {
+          // Bad, should be looking at value
+          return false;
+        }
+        state = eName;
+        aAttrs->AppendElement(
+            Attribute(NS_ConvertUTF16toUTF8(tokens[eName]), tokens[eValue]));
+        tokens[eName].Truncate();
+        tokens[eValue].Truncate();
+        ++itr;
+        continue;
+      default:
+        break;
+    }
+    tokens[state] += *itr;
+    ++itr;
+  }
+  return true;
+}
+
+void ProxyAccessible::Attributes(nsTArray<Attribute>* aAttrs) const {
+  aAttrs->Clear();
+
+  RefPtr<IAccessible> acc;
+  if (!GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return;
+  }
+
+  RefPtr<IAccessible2> acc2;
+  if (FAILED(acc->QueryInterface(IID_IAccessible2,
+                                 (void**)getter_AddRefs(acc2)))) {
+    return;
+  }
+
+  BSTR attrs;
+  HRESULT hr = acc2->get_attributes(&attrs);
+  _bstr_t attrsWrap(attrs, false);
+  if (FAILED(hr)) {
+    return;
+  }
+
+  ConvertBSTRAttributesToArray(
+      nsDependentString((wchar_t*)attrs, attrsWrap.length()), aAttrs);
+}
+
+nsTArray<ProxyAccessible*> ProxyAccessible::RelationByType(
+    RelationType aType) const {
+  RefPtr<IAccessible2_2> acc = QueryInterface<IAccessible2_2>(this);
+  if (!acc) {
+    return nsTArray<ProxyAccessible*>();
+  }
+
+  _bstr_t relationType;
+  for (uint32_t idx = 0; idx < ArrayLength(sRelationTypePairs); idx++) {
+    if (aType == sRelationTypePairs[idx].first) {
+      relationType = sRelationTypePairs[idx].second;
+      break;
+    }
+  }
+
+  if (!relationType) {
+    return nsTArray<ProxyAccessible*>();
+  }
+
+  IUnknown** targets;
+  long nTargets = 0;
+  HRESULT hr =
+      acc->get_relationTargetsOfType(relationType, 0, &targets, &nTargets);
+  if (FAILED(hr)) {
+    return nsTArray<ProxyAccessible*>();
+  }
+
+  nsTArray<ProxyAccessible*> proxies;
+  for (long idx = 0; idx < nTargets; idx++) {
+    IUnknown* target = targets[idx];
+    proxies.AppendElement(GetProxyFor(Document(), target));
+    target->Release();
+  }
+  CoTaskMemFree(targets);
+
+  return proxies;
+}
+
+double ProxyAccessible::CurValue() {
+  RefPtr<IAccessibleValue> acc = QueryInterface<IAccessibleValue>(this);
+  if (!acc) {
+    return UnspecifiedNaN<double>();
+  }
+
+  VARIANT currentValue;
+  HRESULT hr = acc->get_currentValue(&currentValue);
+  if (FAILED(hr) || currentValue.vt != VT_R8) {
+    return UnspecifiedNaN<double>();
+  }
+
+  return currentValue.dblVal;
+}
+
+bool ProxyAccessible::SetCurValue(double aValue) {
+  RefPtr<IAccessibleValue> acc = QueryInterface<IAccessibleValue>(this);
+  if (!acc) {
+    return false;
+  }
+
+  VARIANT currentValue;
+  VariantInit(&currentValue);
+  currentValue.vt = VT_R8;
+  currentValue.dblVal = aValue;
+  HRESULT hr = acc->setCurrentValue(currentValue);
+  return SUCCEEDED(hr);
+}
+
+double ProxyAccessible::MinValue() {
+  RefPtr<IAccessibleValue> acc = QueryInterface<IAccessibleValue>(this);
+  if (!acc) {
+    return UnspecifiedNaN<double>();
+  }
+
+  VARIANT minimumValue;
+  HRESULT hr = acc->get_minimumValue(&minimumValue);
+  if (FAILED(hr) || minimumValue.vt != VT_R8) {
+    return UnspecifiedNaN<double>();
+  }
+
+  return minimumValue.dblVal;
+}
+
+double ProxyAccessible::MaxValue() {
+  RefPtr<IAccessibleValue> acc = QueryInterface<IAccessibleValue>(this);
+  if (!acc) {
+    return UnspecifiedNaN<double>();
+  }
+
+  VARIANT maximumValue;
+  HRESULT hr = acc->get_maximumValue(&maximumValue);
+  if (FAILED(hr) || maximumValue.vt != VT_R8) {
+    return UnspecifiedNaN<double>();
+  }
+
+  return maximumValue.dblVal;
+}
+
+static IA2TextBoundaryType GetIA2TextBoundary(
+    AccessibleTextBoundary aGeckoBoundaryType) {
+  switch (aGeckoBoundaryType) {
+    case nsIAccessibleText::BOUNDARY_CHAR:
+      return IA2_TEXT_BOUNDARY_CHAR;
+    case nsIAccessibleText::BOUNDARY_WORD_START:
+      return IA2_TEXT_BOUNDARY_WORD;
+    case nsIAccessibleText::BOUNDARY_LINE_START:
+      return IA2_TEXT_BOUNDARY_LINE;
+    case nsIAccessibleText::BOUNDARY_PARAGRAPH:
+      return IA2_TEXT_BOUNDARY_PARAGRAPH;
+    default:
+      MOZ_CRASH();
+  }
+}
+
+int32_t ProxyAccessible::OffsetAtPoint(int32_t aX, int32_t aY,
+                                       uint32_t aCoordinateType) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return -1;
+  }
+
+  IA2CoordinateType coordType;
+  if (aCoordinateType ==
+      nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE) {
+    coordType = IA2_COORDTYPE_SCREEN_RELATIVE;
+  } else if (aCoordinateType ==
+             nsIAccessibleCoordinateType::COORDTYPE_PARENT_RELATIVE) {
+    coordType = IA2_COORDTYPE_PARENT_RELATIVE;
+  } else {
+    MOZ_CRASH("unsupported coord type");
+  }
+
+  long offset;
+  HRESULT hr = acc->get_offsetAtPoint(
+      static_cast<long>(aX), static_cast<long>(aY), coordType, &offset);
+  if (FAILED(hr)) {
+    return -1;
+  }
+
+  return static_cast<int32_t>(offset);
+}
+
+bool ProxyAccessible::TextSubstring(int32_t aStartOffset, int32_t aEndOffset,
+                                    nsString& aText) const {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return false;
+  }
+
+  BSTR result;
+  HRESULT hr = acc->get_text(static_cast<long>(aStartOffset),
+                             static_cast<long>(aEndOffset), &result);
+  if (FAILED(hr)) {
+    return false;
+  }
+
+  _bstr_t resultWrap(result, false);
+  aText = (wchar_t*)result;
+
+  return true;
+}
+
+void ProxyAccessible::GetTextBeforeOffset(int32_t aOffset,
+                                          AccessibleTextBoundary aBoundaryType,
+                                          nsString& aText,
+                                          int32_t* aStartOffset,
+                                          int32_t* aEndOffset) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return;
+  }
+
+  BSTR result;
+  long start, end;
+  HRESULT hr = acc->get_textBeforeOffset(
+      aOffset, GetIA2TextBoundary(aBoundaryType), &start, &end, &result);
+  if (FAILED(hr)) {
+    return;
+  }
+
+  _bstr_t resultWrap(result, false);
+  *aStartOffset = start;
+  *aEndOffset = end;
+  aText = (wchar_t*)result;
+}
+
+void ProxyAccessible::GetTextAfterOffset(int32_t aOffset,
+                                         AccessibleTextBoundary aBoundaryType,
+                                         nsString& aText, int32_t* aStartOffset,
+                                         int32_t* aEndOffset) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return;
+  }
+
+  BSTR result;
+  long start, end;
+  HRESULT hr = acc->get_textAfterOffset(
+      aOffset, GetIA2TextBoundary(aBoundaryType), &start, &end, &result);
+  if (FAILED(hr)) {
+    return;
+  }
+
+  _bstr_t resultWrap(result, false);
+  aText = (wchar_t*)result;
+  *aStartOffset = start;
+  *aEndOffset = end;
+}
+
+void ProxyAccessible::GetTextAtOffset(int32_t aOffset,
+                                      AccessibleTextBoundary aBoundaryType,
+                                      nsString& aText, int32_t* aStartOffset,
+                                      int32_t* aEndOffset) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return;
+  }
+
+  BSTR result;
+  long start, end;
+  HRESULT hr = acc->get_textAtOffset(aOffset, GetIA2TextBoundary(aBoundaryType),
+                                     &start, &end, &result);
+  if (FAILED(hr)) {
+    return;
+  }
+
+  _bstr_t resultWrap(result, false);
+  aText = (wchar_t*)result;
+  *aStartOffset = start;
+  *aEndOffset = end;
+}
+
+bool ProxyAccessible::AddToSelection(int32_t aStartOffset, int32_t aEndOffset) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return false;
+  }
+
+  return SUCCEEDED(acc->addSelection(static_cast<long>(aStartOffset),
+                                     static_cast<long>(aEndOffset)));
+}
+
+bool ProxyAccessible::RemoveFromSelection(int32_t aSelectionNum) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return false;
+  }
+
+  return SUCCEEDED(acc->removeSelection(static_cast<long>(aSelectionNum)));
+}
+
+int32_t ProxyAccessible::CaretOffset() {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return -1;
+  }
+
+  long offset;
+  HRESULT hr = acc->get_caretOffset(&offset);
+  if (FAILED(hr)) {
+    return -1;
+  }
+
+  return static_cast<int32_t>(offset);
+}
+
+void ProxyAccessible::SetCaretOffset(int32_t aOffset) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return;
+  }
+
+  acc->setCaretOffset(static_cast<long>(aOffset));
+}
+
+/**
+ * aScrollType should be one of the nsIAccessiblescrollType constants.
+ */
+void ProxyAccessible::ScrollSubstringTo(int32_t aStartOffset,
+                                        int32_t aEndOffset,
+                                        uint32_t aScrollType) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return;
+  }
+
+  acc->scrollSubstringTo(static_cast<long>(aStartOffset),
+                         static_cast<long>(aEndOffset),
+                         static_cast<IA2ScrollType>(aScrollType));
+}
+
+/**
+ * aCoordinateType is one of the nsIAccessibleCoordinateType constants.
+ */
+void ProxyAccessible::ScrollSubstringToPoint(int32_t aStartOffset,
+                                             int32_t aEndOffset,
+                                             uint32_t aCoordinateType,
+                                             int32_t aX, int32_t aY) {
+  RefPtr<IAccessibleText> acc = QueryInterface<IAccessibleText>(this);
+  if (!acc) {
+    return;
+  }
+
+  IA2CoordinateType coordType;
+  if (aCoordinateType ==
+      nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE) {
+    coordType = IA2_COORDTYPE_SCREEN_RELATIVE;
+  } else if (aCoordinateType ==
+             nsIAccessibleCoordinateType::COORDTYPE_PARENT_RELATIVE) {
+    coordType = IA2_COORDTYPE_PARENT_RELATIVE;
+  } else {
+    MOZ_CRASH("unsupported coord type");
+  }
+
+  acc->scrollSubstringToPoint(static_cast<long>(aStartOffset),
+                              static_cast<long>(aEndOffset), coordType,
+                              static_cast<long>(aX), static_cast<long>(aY));
+}
+
+uint32_t ProxyAccessible::StartOffset(bool* aOk) {
+  RefPtr<IAccessibleHyperlink> acc = QueryInterface<IAccessibleHyperlink>(this);
+  if (!acc) {
+    *aOk = false;
+    return 0;
+  }
+
+  long startOffset;
+  *aOk = SUCCEEDED(acc->get_startIndex(&startOffset));
+  return static_cast<uint32_t>(startOffset);
+}
+
+uint32_t ProxyAccessible::EndOffset(bool* aOk) {
+  RefPtr<IAccessibleHyperlink> acc = QueryInterface<IAccessibleHyperlink>(this);
+  if (!acc) {
+    *aOk = false;
+    return 0;
+  }
+
+  long endOffset;
+  *aOk = SUCCEEDED(acc->get_endIndex(&endOffset));
+  return static_cast<uint32_t>(endOffset);
+}
+
+bool ProxyAccessible::IsLinkValid() {
+  RefPtr<IAccessibleHyperlink> acc = QueryInterface<IAccessibleHyperlink>(this);
+  if (!acc) {
+    return false;
+  }
+
+  boolean valid;
+  if (FAILED(acc->get_valid(&valid))) {
+    return false;
+  }
+
+  return valid;
+}
+
+uint32_t ProxyAccessible::AnchorCount(bool* aOk) {
+  *aOk = false;
+  RefPtr<IGeckoCustom> custom = QueryInterface<IGeckoCustom>(this);
+  if (!custom) {
+    return 0;
+  }
+
+  long count;
+  if (FAILED(custom->get_anchorCount(&count))) {
+    return 0;
+  }
+
+  *aOk = true;
+  return count;
+}
+
+ProxyAccessible* ProxyAccessible::AnchorAt(uint32_t aIdx) {
+  RefPtr<IAccessibleHyperlink> link =
+      QueryInterface<IAccessibleHyperlink>(this);
+  if (!link) {
+    return nullptr;
+  }
+
+  VARIANT anchor;
+  if (FAILED(link->get_anchor(aIdx, &anchor))) {
+    return nullptr;
+  }
+
+  MOZ_ASSERT(anchor.vt == VT_UNKNOWN);
+  ProxyAccessible* proxyAnchor = GetProxyFor(Document(), anchor.punkVal);
+  anchor.punkVal->Release();
+  return proxyAnchor;
+}
+
+void ProxyAccessible::DOMNodeID(nsString& aID) {
+  aID.Truncate();
+  RefPtr<IGeckoCustom> custom = QueryInterface<IGeckoCustom>(this);
+  if (!custom) {
+    return;
+  }
+
+  BSTR result;
+  HRESULT hr = custom->get_DOMNodeID(&result);
+  _bstr_t resultWrap(result, false);
+  if (FAILED(hr)) {
+    return;
+  }
+  aID = (wchar_t*)resultWrap;
+}
+
+void ProxyAccessible::TakeFocus() {
+  RefPtr<IAccessible> acc;
+  if (!GetCOMInterface((void**)getter_AddRefs(acc))) {
+    return;
+  }
+  acc->accSelect(SELFLAG_TAKEFOCUS, kChildIdSelf);
+}
+
+ProxyAccessible* ProxyAccessible::ChildAtPoint(
+    int32_t aX, int32_t aY, Accessible::EWhichChildAtPoint aWhichChild) {
+  RefPtr<IAccessible2_2> target = QueryInterface<IAccessible2_2>(this);
+  if (!target) {
+    return nullptr;
+  }
+  DocAccessibleParent* doc = Document();
+  ProxyAccessible* proxy = this;
+  // accHitTest only does direct children, but we might want the deepest child.
+  for (;;) {
+    VARIANT childVar;
+    if (FAILED(target->accHitTest(aX, aY, &childVar)) ||
+        childVar.vt == VT_EMPTY) {
+      return nullptr;
+    }
+    if (childVar.vt == VT_I4 && childVar.lVal == CHILDID_SELF) {
+      break;
+    }
+    MOZ_ASSERT(childVar.vt == VT_DISPATCH && childVar.pdispVal);
+    target = nullptr;
+    childVar.pdispVal->QueryInterface(IID_IAccessible2_2,
+                                      getter_AddRefs(target));
+    childVar.pdispVal->Release();
+    if (!target) {
+      return nullptr;
+    }
+    // We can't always use GetProxyFor because it can't cross document
+    // boundaries.
+    if (proxy->ChildrenCount() == 1) {
+      proxy = proxy->ChildAt(0);
+      if (proxy->IsDoc()) {
+        // We're crossing into a child document.
+        doc = proxy->AsDoc();
+      }
+    } else {
+      proxy = GetProxyFor(doc, target);
+    }
+    if (aWhichChild == Accessible::eDirectChild) {
+      break;
+    }
+  }
+  return proxy;
+}
+
+}  // namespace a11y
+}  // namespace mozilla