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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=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 "ServiceProvider.h"

#include "ApplicationAccessibleWrap.h"
#include "DocAccessible.h"
#include "nsAccUtils.h"
#include "nsCoreUtils.h"
#include "Relation.h"
#include "uiaRawElmProvider.h"

#include "mozilla/Preferences.h"

#include "ISimpleDOM.h"

namespace mozilla {
namespace a11y {

IMPL_IUNKNOWN_QUERY_HEAD(ServiceProvider)
IMPL_IUNKNOWN_QUERY_IFACE(IServiceProvider)
IMPL_IUNKNOWN_QUERY_TAIL_AGGREGATED(mAccessible)

////////////////////////////////////////////////////////////////////////////////
// IServiceProvider

STDMETHODIMP
ServiceProvider::QueryService(REFGUID aGuidService, REFIID aIID,
                              void** aInstancePtr) {
  if (!aInstancePtr) return E_INVALIDARG;

  *aInstancePtr = nullptr;

  // UIA IAccessibleEx
  if (aGuidService == IID_IAccessibleEx &&
      Preferences::GetBool("accessibility.uia.enable")) {
    uiaRawElmProvider* accEx = new uiaRawElmProvider(mAccessible);
    HRESULT hr = accEx->QueryInterface(aIID, aInstancePtr);
    if (FAILED(hr)) delete accEx;

    return hr;
  }

  // Provide a special service ID for getting the accessible for the browser tab
  // document that contains this accessible object. If this accessible object
  // is not inside a browser tab then the service fails with E_NOINTERFACE.
  // A use case for this is for screen readers that need to switch context or
  // 'virtual buffer' when focus moves from one browser tab area to another.
  static const GUID SID_IAccessibleContentDocument = {
      0xa5d8e1f3,
      0x3571,
      0x4d8f,
      {0x95, 0x21, 0x07, 0xed, 0x28, 0xfb, 0x07, 0x2e}};
  if (aGuidService == SID_IAccessibleContentDocument) {
    if (aIID != IID_IAccessible) return E_NOINTERFACE;

    Relation rel =
        mAccessible->RelationByType(RelationType::CONTAINING_TAB_PANE);
    AccessibleWrap* tabDoc = static_cast<AccessibleWrap*>(rel.Next());
    if (!tabDoc) return E_NOINTERFACE;

    *aInstancePtr = static_cast<IAccessible*>(tabDoc);
    (reinterpret_cast<IUnknown*>(*aInstancePtr))->AddRef();
    return S_OK;
  }

  // Can get to IAccessibleApplication from any node via QS
  // Note: in case of JAWS we want to check if aIID is
  // IID_IAccessibleApplication.
  if (aGuidService == IID_IAccessibleApplication ||
      aIID == IID_IAccessibleApplication) {
    ApplicationAccessibleWrap* applicationAcc =
        static_cast<ApplicationAccessibleWrap*>(ApplicationAcc());
    if (!applicationAcc) return E_NOINTERFACE;

    return applicationAcc->QueryInterface(aIID, aInstancePtr);
  }

  static const GUID IID_SimpleDOMDeprecated = {
      0x0c539790,
      0x12e4,
      0x11cf,
      {0xb6, 0x61, 0x00, 0xaa, 0x00, 0x4c, 0xd6, 0xd8}};
  if (aGuidService == IID_ISimpleDOMNode ||
      aGuidService == IID_SimpleDOMDeprecated ||
      aGuidService == IID_IAccessible || aGuidService == IID_IAccessible2)
    return mAccessible->QueryInterface(aIID, aInstancePtr);

  return E_INVALIDARG;
}

}  // namespace a11y
}  // namespace mozilla