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#include <QtCore/QtConfig>
#ifndef QT_NO_ACCESSIBILITY


#include <private/qsystemlibrary_p.h>

#include <QtCore/qlocale.h>
#include <QtCore/qmap.h>
#include <QtCore/qpair.h>
#include <QtCore/qpointer.h>
#include <QtGui/qaccessible.h>
#include <QtGui/private/qguiapplication_p.h>
#include <qpa/qplatformnativeinterface.h>
#include <qpa/qplatformintegration.h>
#include <QtGui/qwindow.h>
#include <QtGui/qguiapplication.h>
#include <QtFontDatabaseSupport/private/qwindowsfontdatabase_p.h> // registry helper

#include "qwindowsaccessibility.h"
#ifdef Q_CC_MINGW
#   include "qwindowsmsaaaccessible.h"
#else
#   include "iaccessible2.h"
#endif
#include "comutils.h"

#include <oleacc.h>

//#include <uiautomationcoreapi.h>
#ifndef UiaRootObjectId
#define UiaRootObjectId        -25
#endif

#include <winuser.h>
#if !defined(WINABLEAPI)
#  include <winable.h>
#endif

#include <servprov.h>
#if !defined(Q_CC_BOR) && !defined (Q_CC_GNU)
#include <comdef.h>
#endif

#include <QtCore/qt_windows.h>

QT_BEGIN_NAMESPACE

/*!
    \!internal
    \class QWindowsAccessibility

    Implements QPlatformAccessibility

*/
QWindowsAccessibility::QWindowsAccessibility()
{
}

// Retrieve sound name by checking the icon property of a message box
static inline QString messageBoxAlertSound(const QObject *messageBox)
{
    enum MessageBoxIcon { // Keep in sync with QMessageBox::Icon
        Information = 1,
        Warning = 2,
        Critical = 3
    };
    switch (messageBox->property("icon").toInt()) {
    case Information:
        return QStringLiteral("SystemAsterisk");
    case Warning:
        return QStringLiteral("SystemExclamation");
    case Critical:
        return QStringLiteral("SystemHand");
    }
    return QString();
}

static QString soundFileName(const QString &soundName)
{
    const QString key = QStringLiteral("AppEvents\\Schemes\\Apps\\.Default\\")
        + soundName + QStringLiteral("\\.Current");
    return QWindowsFontDatabase::readRegistryString(HKEY_CURRENT_USER,
                                                    reinterpret_cast<const wchar_t *>(key.utf16()), L"");
}

void QWindowsAccessibility::notifyAccessibilityUpdate(QAccessibleEvent *event)
{
    QString soundName;
    switch (event->type()) {
    case QAccessible::PopupMenuStart:
        soundName = QLatin1String("MenuPopup");
        break;

    case QAccessible::MenuCommand:
        soundName = QLatin1String("MenuCommand");
        break;

    case QAccessible::Alert:
        soundName = event->object()->inherits("QMessageBox") ?
            messageBoxAlertSound(event->object()) : QStringLiteral("SystemAsterisk");
        break;
    default:
        break;
    }

    if (!soundName.isEmpty() && !soundFileName(soundName).isEmpty()) {
        PlaySound(reinterpret_cast<const wchar_t *>(soundName.utf16()), 0,
                  SND_ALIAS | SND_ASYNC | SND_NODEFAULT | SND_NOWAIT);
    }

    // An event has to be associated with a window,
    // so find the first parent that is a widget and that has a WId
    QAccessibleInterface *iface = event->accessibleInterface();
    if (!isActive() || !iface || !iface->isValid())
        return;
    QWindow *window = QWindowsAccessibility::windowHelper(iface);

    if (!window) {
        window = QGuiApplication::focusWindow();
        if (!window)
            return;
    }

    QPlatformNativeInterface *platform = QGuiApplication::platformNativeInterface();
    if (!window->handle()) // Called before show(), no native window yet.
        return;
    const HWND hWnd = reinterpret_cast<HWND>(platform->nativeResourceForWindow("handle", window));

    if (event->type() != QAccessible::MenuCommand && // MenuCommand is faked
        event->type() != QAccessible::ObjectDestroyed) {
        ::NotifyWinEvent(event->type(), hWnd, OBJID_CLIENT, QAccessible::uniqueId(iface));
    }
}

QWindow *QWindowsAccessibility::windowHelper(const QAccessibleInterface *iface)
{
    QWindow *window = iface->window();
    if (!window) {
        QAccessibleInterface *acc = iface->parent();
        while (acc && acc->isValid() && !window) {
            window = acc->window();
            QAccessibleInterface *par = acc->parent();
            acc = par;
        }
    }
    return window;
}

/*!
  \internal
  helper to wrap a QAccessibleInterface inside a IAccessible*
*/
IAccessible *QWindowsAccessibility::wrap(QAccessibleInterface *acc)
{
    if (!acc)
        return 0;

    // ### FIXME: maybe we should accept double insertions into the cache
    if (!QAccessible::uniqueId(acc))
        QAccessible::registerAccessibleInterface(acc);

# ifdef Q_CC_MINGW
    QWindowsMsaaAccessible *wacc = new QWindowsMsaaAccessible(acc);
# else
    QWindowsIA2Accessible *wacc = new QWindowsIA2Accessible(acc);
# endif
    IAccessible *iacc = 0;
    wacc->QueryInterface(IID_IAccessible, reinterpret_cast<void **>(&iacc));
    return iacc;
}

bool QWindowsAccessibility::handleAccessibleObjectFromWindowRequest(HWND hwnd, WPARAM wParam, LPARAM lParam, LRESULT *lResult)
{
    if (static_cast<long>(lParam) == static_cast<long>(UiaRootObjectId)) {
        /* For UI Automation */
    } else if (DWORD(lParam) == DWORD(OBJID_CLIENT)) {
        // Start handling accessibility internally
        QGuiApplicationPrivate::platformIntegration()->accessibility()->setActive(true);
        // Ignoring all requests while starting up
        // ### Maybe QPA takes care of this???
        if (QCoreApplication::startingUp() || QCoreApplication::closingDown())
            return false;

        typedef LRESULT (WINAPI *PtrLresultFromObject)(REFIID, WPARAM, LPUNKNOWN);
        static PtrLresultFromObject ptrLresultFromObject = 0;
        static bool oleaccChecked = false;

        if (!oleaccChecked) {
            oleaccChecked = true;
            ptrLresultFromObject = reinterpret_cast<PtrLresultFromObject>(QSystemLibrary::resolve(QLatin1String("oleacc"), "LresultFromObject"));
        }

        if (ptrLresultFromObject) {
            QWindow *window = QWindowsContext::instance()->findWindow(hwnd);
            if (window) {
                QAccessibleInterface *acc = window->accessibleRoot();
                if (acc) {
                    if (IAccessible *iface = wrap(acc)) {
                        *lResult = ptrLresultFromObject(IID_IAccessible, wParam, iface);  // ref == 2
                        if (*lResult) {
                            iface->Release(); // the client will release the object again, and then it will destroy itself
                        }
                        return true;
                    }
                }
            }
        }
    }
    return false;
}

QT_END_NAMESPACE

#endif //QT_NO_ACCESSIBILITY