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#include "qaccessiblecache_p.h"

#include <QtCore/qdebug.h>

#include <QtCore/qloggingcategory.h>

#ifndef QT_NO_ACCESSIBILITY

QT_BEGIN_NAMESPACE

Q_LOGGING_CATEGORY(lcAccessibilityCache, "qt.accessibility.cache");

/*!

    \class QAccessibleCache

    \internal

    \brief Maintains a cache of accessible interfaces.

*/

static QAccessibleCache *accessibleCache = nullptr;

static void cleanupAccessibleCache()

{

    delete accessibleCache;

    accessibleCache = nullptr;

}

QAccessibleCache::~QAccessibleCache()

{

    for (QAccessible::Id id: idToInterface.keys())

        deleteInterface(id);

}

QAccessibleCache *QAccessibleCache::instance()

{

    if (!accessibleCache) {

        accessibleCache = new QAccessibleCache;

        qAddPostRoutine(cleanupAccessibleCache);

    }

    return accessibleCache;

}

/*

  The ID is always in the range [INT_MAX+1, UINT_MAX].

  This makes it easy on windows to reserve the positive integer range

  for the index of a child and not clash with the unique ids.

*/

QAccessible::Id QAccessibleCache::acquireId() const

{

    static const QAccessible::Id FirstId = QAccessible::Id(INT_MAX) + 1;

    static QAccessible::Id lastUsedId = FirstId;

    while (idToInterface.contains(lastUsedId)) {

        // (wrap back when when we reach UINT_MAX - 1)

        // -1 because on Android -1 is taken for the "View" so just avoid it completely for consistency

        if (lastUsedId == UINT_MAX - 1)

            lastUsedId = FirstId;

        else

            ++lastUsedId;

    }

    return lastUsedId;

}

QAccessibleInterface *QAccessibleCache::interfaceForId(QAccessible::Id id) const

{

    return idToInterface.value(id);

}

QAccessible::Id QAccessibleCache::idForInterface(QAccessibleInterface *iface) const

{

    return interfaceToId.value(iface);

}

QAccessible::Id QAccessibleCache::insert(QObject *object, QAccessibleInterface *iface) const

{

    Q_ASSERT(iface);

    Q_UNUSED(object)

    // object might be 0

    Q_ASSERT(!objectToId.contains(object));

    Q_ASSERT_X(!interfaceToId.contains(iface), "", "Accessible interface inserted into cache twice!");

    QAccessible::Id id = acquireId();

    QObject *obj = iface->object();

    Q_ASSERT(object == obj);

    if (obj) {

        objectToId.insert(obj, id);

        connect(obj, &QObject::destroyed, this, &QAccessibleCache::objectDestroyed);

    }

    idToInterface.insert(id, iface);

    interfaceToId.insert(iface, id);

    qCDebug(lcAccessibilityCache) << "insert - id:" << id << " iface:" << iface;

    return id;

}

void QAccessibleCache::objectDestroyed(QObject* obj)

{

    QAccessible::Id id = objectToId.value(obj);

    if (id) {

        Q_ASSERT_X(idToInterface.contains(id), "", "QObject with accessible interface deleted, where interface not in cache!");

        deleteInterface(id, obj);

    }

}

void QAccessibleCache::deleteInterface(QAccessible::Id id, QObject *obj)

{

    QAccessibleInterface *iface = idToInterface.take(id);

    qCDebug(lcAccessibilityCache) << "delete - id:" << id << " iface:" << iface;

    if (!iface) // the interface may be deleted already

        return;

    interfaceToId.take(iface);

    if (!obj)

        obj = iface->object();

    if (obj)

        objectToId.remove(obj);

    delete iface;

#ifdef Q_OS_MAC

    removeCocoaElement(id);

#endif

}

QT_END_NAMESPACE

#include "moc_qaccessiblecache_p.cpp"

#endif