// Copyright (C) 2020 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant

#include "qv4resolvedtypereference_p.h"

#include <QtQml/private/qqmlengine_p.h>
#include <QtQml/qqmlpropertymap.h>
#include <QtCore/qcryptographichash.h>

QT_BEGIN_NAMESPACE

namespace QV4 {

template <typename T>
bool qtTypeInherits(const QMetaObject *mo) {
    while (mo) {
        if (mo == &T::staticMetaObject)
            return true;
        mo = mo->superClass();
    }
    return false;
}

void ResolvedTypeReference::doDynamicTypeCheck()
{
    const QMetaObject *mo = nullptr;
    if (m_typePropertyCache) {
        mo = m_typePropertyCache->firstCppMetaObject();
    } else if (m_type.isValid()) {
        mo = m_type.metaObject();
    } else if (m_compilationUnit) {
        if (const auto cache = m_compilationUnit->rootPropertyCache())
            mo = cache->firstCppMetaObject();
    }
    m_isFullyDynamicType = qtTypeInherits<QQmlPropertyMap>(mo);
}

/*!
Returns the property cache, creating one if it doesn't already exist.  The cache is not referenced.
*/
QQmlPropertyCache::ConstPtr ResolvedTypeReference::createPropertyCache()
{
    if (m_typePropertyCache) {
        return m_typePropertyCache;
    } else if (m_type.isValid()) {
        const QMetaObject *metaObject = m_type.metaObject();
        if (!metaObject) // value type of non-Q_GADGET base with extension
            metaObject = m_type.extensionMetaObject();
        if (metaObject)
            m_typePropertyCache = QQmlMetaType::propertyCache(metaObject, m_version);
        return m_typePropertyCache;
    } else {
        Q_ASSERT(m_compilationUnit);
        return m_compilationUnit->rootPropertyCache();
    }
}

bool ResolvedTypeReference::addToHash(
        QCryptographicHash *hash, QHash<quintptr, QByteArray> *checksums)
{
    if (m_type.isInlineComponentType()) {

        // A reference to an inline component in the same file will have
        // - no compilation unit since we cannot resolve the compilation unit before it's built.
        // - a property cache since we've assigned one in buildMetaObjectsIncrementally().
        // - a QQmlType that says it's an inline component.
        // We don't have to add such a thing to the hash since if it changes, the QML document
        // itself changes, leading to a new timestamp, which is checked before the checksum.
        if (!m_compilationUnit)
            return !m_typePropertyCache.isNull();

    } else if (m_type.isValid()) {
        bool ok = false;
        if (QQmlPropertyCache::ConstPtr propertyCache = createPropertyCache())
            hash->addData(propertyCache->checksum(checksums, &ok));
        else
            Q_ASSERT(m_type.module() == QLatin1String("QML")); // a builtin without metaobject
        return ok;
    }

    // If there is no compilation unit and no type, then it's a self reference.
    // We don't have to add anything to the hash since if it changes, the QML document itself
    // changes, leading to a new timestamp, which is checked before the checksum.
    // Self references don't even set m_typePropertyCache, so there is nothing to check here.
    if (!m_compilationUnit)
        return true;

    hash->addData({m_compilationUnit->unitData()->md5Checksum,
                  sizeof(m_compilationUnit->unitData()->md5Checksum)});
    return true;
}

} // namespace QV4

QT_END_NAMESPACE
