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**
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** contained in the Technology Preview License Agreement accompanying
** this package.
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#include <private/qlistmodelinterface_p.h>
#include "qmlgraphicsitem.h"
#include <qmlcontext.h>
#include <qmlexpression.h>
#include <private/qmlpackage_p.h>
#include "qhash.h"
#include "qlist.h"
#include "private/qobject_p.h"
#include "private/qmetaobjectbuilder_p.h"
#include <private/qmlopenmetaobject_p.h>
#include <private/qmllistaccessor_p.h>
#include "qmlinfo.h"
#include "qmlgraphicsvisualitemmodel_p.h"
#include "private/qguard_p.h"
#include <QtCore/qdebug.h>

QML_DECLARE_TYPE(QListModelInterface)

QT_BEGIN_NAMESPACE

class QmlGraphicsVisualItemModelAttached : public QObject
{
    Q_OBJECT

public:
    QmlGraphicsVisualItemModelAttached(QObject *parent)
        : QObject(parent), m_index(0) {}
    ~QmlGraphicsVisualItemModelAttached() {
        attachedProperties.remove(parent());
    }

    Q_PROPERTY(int index READ index NOTIFY indexChanged)
    int index() const { return m_index; }
    void setIndex(int idx) {
        if (m_index != idx) {
            m_index = idx;
            emit indexChanged();
        }
    }

    static QmlGraphicsVisualItemModelAttached *properties(QObject *obj) {
        QmlGraphicsVisualItemModelAttached *rv = attachedProperties.value(obj);
        if (!rv) {
            rv = new QmlGraphicsVisualItemModelAttached(obj);
            attachedProperties.insert(obj, rv);
        }
        return rv;
    }

Q_SIGNALS:
    void indexChanged();

public:
    int m_index;

    static QHash<QObject*, QmlGraphicsVisualItemModelAttached*> attachedProperties;
};

QHash<QObject*, QmlGraphicsVisualItemModelAttached*> QmlGraphicsVisualItemModelAttached::attachedProperties;


class QmlGraphicsVisualItemModelPrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QmlGraphicsVisualItemModel)
public:
    QmlGraphicsVisualItemModelPrivate() : QObjectPrivate(), children(this) {}

    struct ItemList : public QmlConcreteList<QmlGraphicsItem *>
    {
        ItemList(QmlGraphicsVisualItemModelPrivate *m) : QmlConcreteList<QmlGraphicsItem *>(), model(m) {}

        void append(QmlGraphicsItem *item);

        QmlGraphicsVisualItemModelPrivate *model;
    };

    void itemAppended() {
        Q_Q(QmlGraphicsVisualItemModel);
        QmlGraphicsVisualItemModelAttached *attached = QmlGraphicsVisualItemModelAttached::properties(children.last());
        attached->setIndex(children.count()-1);
        emit q->itemsInserted(children.count()-1, 1);
        emit q->countChanged();
    }

    void emitChildrenChanged() {
        Q_Q(QmlGraphicsVisualItemModel);
        emit q->childrenChanged();
    }
    ItemList children;
};


/*!
    \qmlclass VisualItemModel QmlGraphicsVisualItemModel
    \brief The VisualItemModel allows items to be provided to a view.

    The children of the VisualItemModel are provided in a model which
    can be used in a view.  Note that no delegate should be
    provided to a view since the VisualItemModel contains the
    visual delegate (items).

    An item can determine its index within the
    model via the VisualItemModel.index attached property.

    The example below places three colored rectangles in a ListView.
    \code
    Item {
        VisualItemModel {
            id: itemModel
            Rectangle { height: 30; width: 80; color: "red" }
            Rectangle { height: 30; width: 80; color: "green" }
            Rectangle { height: 30; width: 80; color: "blue" }
        }

        ListView {
            anchors.fill: parent
            model: itemModel
        }
    }
    \endcode
*/
QmlGraphicsVisualItemModel::QmlGraphicsVisualItemModel()
    : QmlGraphicsVisualModel(*(new QmlGraphicsVisualItemModelPrivate))
{
}

QmlList<QmlGraphicsItem *> *QmlGraphicsVisualItemModel::children()
{
    Q_D(QmlGraphicsVisualItemModel);
    return &(d->children);
}

/*!
    \qmlproperty int VisualItemModel::count

    The number of items in the model.  This property is readonly.
*/
int QmlGraphicsVisualItemModel::count() const
{
    Q_D(const QmlGraphicsVisualItemModel);
    return d->children.count();
}

bool QmlGraphicsVisualItemModel::isValid() const
{
    return true;
}

QmlGraphicsItem *QmlGraphicsVisualItemModel::item(int index, bool)
{
    Q_D(QmlGraphicsVisualItemModel);
    return d->children.at(index);
}

QmlGraphicsVisualModel::ReleaseFlags QmlGraphicsVisualItemModel::release(QmlGraphicsItem *)
{
    // Nothing to do
    return 0;
}

void QmlGraphicsVisualItemModel::completeItem()
{
    // Nothing to do
}

QVariant QmlGraphicsVisualItemModel::evaluate(int index, const QString &expression, QObject *objectContext)
{
    Q_D(QmlGraphicsVisualItemModel);
    QmlContext *ccontext = qmlContext(this);
    QmlContext *ctxt = new QmlContext(ccontext);
    ctxt->addDefaultObject(d->children.at(index));
    QmlExpression e(ctxt, expression, objectContext);
    e.setTrackChange(false);
    QVariant value = e.value();
    delete ctxt;
    return value;
}

int QmlGraphicsVisualItemModel::indexOf(QmlGraphicsItem *item, QObject *) const
{
    Q_D(const QmlGraphicsVisualItemModel);
    return d->children.indexOf(item);
}

void QmlGraphicsVisualItemModelPrivate::ItemList::append(QmlGraphicsItem *item)
{
    QmlConcreteList<QmlGraphicsItem*>::append(item);
    item->QObject::setParent(model->q_ptr);
    model->itemAppended();

    model->emitChildrenChanged();
}

QmlGraphicsVisualItemModelAttached *QmlGraphicsVisualItemModel::qmlAttachedProperties(QObject *obj)
{
    return QmlGraphicsVisualItemModelAttached::properties(obj);
}


class QmlGraphicsVisualDataModelParts;
class QmlGraphicsVisualDataModelData;
class QmlGraphicsVisualDataModelPrivate : public QObjectPrivate
{
public:
    QmlGraphicsVisualDataModelPrivate(QmlContext *);

    static QmlGraphicsVisualDataModelPrivate *get(QmlGraphicsVisualDataModel *m) {
        return static_cast<QmlGraphicsVisualDataModelPrivate *>(QObjectPrivate::get(m));
    }

    QGuard<QListModelInterface> m_listModelInterface;
    QGuard<QAbstractItemModel> m_abstractItemModel;
    QGuard<QmlGraphicsVisualDataModel> m_visualItemModel;
    QString m_part;

    QmlComponent *m_delegate;
    QmlContext *m_context;
    QList<int> m_roles;
    QHash<QString,int> m_roleNames;
    void ensureRoles() {
        if (m_roleNames.isEmpty()) {
            if (m_listModelInterface) {
                m_roles = m_listModelInterface->roles();
                for (int ii = 0; ii < m_roles.count(); ++ii)
                    m_roleNames.insert(m_listModelInterface->toString(m_roles.at(ii)), m_roles.at(ii));
                if (m_roles.count() == 1)
                    m_roleNames.insert(QLatin1String("modelData"), m_roles.at(0));
            } else if (m_abstractItemModel) {
                for (QHash<int,QByteArray>::const_iterator it = m_abstractItemModel->roleNames().begin();
                        it != m_abstractItemModel->roleNames().end(); ++it) {
                    m_roles.append(it.key());
                    m_roleNames.insert(QString::fromUtf8(*it), it.key());
                }
                if (m_roles.count() == 1)
                    m_roleNames.insert(QLatin1String("modelData"), m_roles.at(0));
            } else if (m_listAccessor) {
                m_roleNames.insert(QLatin1String("modelData"), 0);
                if (m_listAccessor->type() == QmlListAccessor::Instance) {
                    if (QObject *object = m_listAccessor->at(0).value<QObject*>()) {
                        int count = object->metaObject()->propertyCount();
                        for (int ii = 1; ii < count; ++ii) {
                            const QMetaProperty &prop = object->metaObject()->property(ii);
                            m_roleNames.insert(QString::fromUtf8(prop.name()), 0);
                        }
                    }
                }
            }
        }
    }

    struct ObjectRef {
        ObjectRef(QObject *object=0) : obj(object), ref(1) {}
        QObject *obj;
        int ref;
    };
    class Cache : public QHash<int, ObjectRef> {
    public:
        QObject *getItem(int index) {
            QObject *item = 0;
            QHash<int,ObjectRef>::iterator it = find(index);
            if (it != end()) {
                (*it).ref++;
                item = (*it).obj;
            }
            return item;
        }
        QObject *item(int index) {
            QObject *item = 0;
            QHash<int, ObjectRef>::const_iterator it = find(index);
            if (it != end())
                item = (*it).obj;
            return item;
        }
        void insertItem(int index, QObject *obj) {
            insert(index, ObjectRef(obj));
        }
        bool releaseItem(QObject *obj) {
            QHash<int, ObjectRef>::iterator it = begin();
            for (; it != end(); ++it) {
                ObjectRef &objRef = *it;
                if (objRef.obj == obj) {
                    if (--objRef.ref == 0) {
                        erase(it);
                        return true;
                    }
                    break;
                }
            }
            return false;
        }
    };

    Cache m_cache;
    QHash<QObject *, QmlPackage*> m_packaged;

    QmlGraphicsVisualDataModelParts *m_parts;
    friend class QmlGraphicsVisualItemParts;

    QmlGraphicsVisualDataModelData *data(QObject *item);

    QVariant m_modelVariant;
    QmlListAccessor *m_listAccessor;

    int modelCount() const {
        if (m_visualItemModel)
            return m_visualItemModel->count();
        if (m_listModelInterface)
            return m_listModelInterface->count();
        if (m_abstractItemModel)
            return m_abstractItemModel->rowCount();
        if (m_listAccessor)
            return m_listAccessor->count();
        return 0;
    }
};

class QmlGraphicsVisualDataModelDataMetaObject : public QmlOpenMetaObject
{
public:
    QmlGraphicsVisualDataModelDataMetaObject(QObject *parent)
    : QmlOpenMetaObject(parent) {}

    virtual QVariant propertyCreated(int, QMetaPropertyBuilder &);
    virtual int createProperty(const char *, const char *);

private:
    friend class QmlGraphicsVisualDataModelData;
    QList<int> roles;
};

class QmlGraphicsVisualDataModelData : public QObject
{
Q_OBJECT
public:
    QmlGraphicsVisualDataModelData(int index, QmlGraphicsVisualDataModel *model);
    ~QmlGraphicsVisualDataModelData();

    Q_PROPERTY(int index READ index NOTIFY indexChanged)
    int index() const;
    void setIndex(int index);

    int count() const;
    int role(int) const;
    void setValue(int, const QVariant &);

Q_SIGNALS:
    void indexChanged();

private:
    friend class QmlGraphicsVisualDataModelDataMetaObject;
    int m_index;
    QGuard<QmlGraphicsVisualDataModel> m_model;
    QmlGraphicsVisualDataModelDataMetaObject *m_meta;
};

int QmlGraphicsVisualDataModelData::count() const
{
    return m_meta->count();
}

int QmlGraphicsVisualDataModelData::role(int id) const
{
    Q_ASSERT(id >= 0 && id < count());
    return m_meta->roles.at(id);
}

void QmlGraphicsVisualDataModelData::setValue(int id, const QVariant &val)
{
    m_meta->setValue(id, val);
}

int QmlGraphicsVisualDataModelDataMetaObject::createProperty(const char *name, const char *type)
{
    QmlGraphicsVisualDataModelData *data =
        static_cast<QmlGraphicsVisualDataModelData *>(object());

    if (!data->m_model)
        return -1;

    QmlGraphicsVisualDataModelPrivate *model = QmlGraphicsVisualDataModelPrivate::get(data->m_model);

    if ((!model->m_listModelInterface || !model->m_abstractItemModel) && model->m_listAccessor) {
        model->ensureRoles();
        if (model->m_roleNames.contains(QString::fromUtf8(name))) {
            return QmlOpenMetaObject::createProperty(name, type);
        } else if (model->m_listAccessor->type() == QmlListAccessor::QmlList) {
            QObject *object = model->m_listAccessor->at(data->m_index).value<QObject*>();
            if (object && object->property(name).isValid())
                return QmlOpenMetaObject::createProperty(name, type);
        }
    } else {
        model->ensureRoles();
        QString sname = QString::fromUtf8(name);
        if (model->m_roleNames.contains(sname))
            return QmlOpenMetaObject::createProperty(name, type);
    }
    return -1;
}

QVariant 
QmlGraphicsVisualDataModelDataMetaObject::propertyCreated(int, QMetaPropertyBuilder &prop)
{
    prop.setWritable(false);

    QmlGraphicsVisualDataModelData *data =
        static_cast<QmlGraphicsVisualDataModelData *>(object());

    Q_ASSERT(data->m_model);
    QmlGraphicsVisualDataModelPrivate *model = QmlGraphicsVisualDataModelPrivate::get(data->m_model);

    QString name = QString::fromUtf8(prop.name());
    if ((!model->m_listModelInterface || !model->m_abstractItemModel) && model->m_listAccessor) {
        if (name == QLatin1String("modelData")) {
            if (model->m_listAccessor->type() == QmlListAccessor::Instance) {
                QObject *object = model->m_listAccessor->at(0).value<QObject*>();
                return object->metaObject()->property(1).read(object); // the first property after objectName
            }
            return model->m_listAccessor->at(data->m_index);
        } else {
            // return any property of a single object instance.
            QObject *object = model->m_listAccessor->at(data->m_index).value<QObject*>();
            return object->property(prop.name());
        }
    } else if (model->m_listModelInterface) {
        model->ensureRoles();
        QHash<QString,int>::const_iterator it = model->m_roleNames.find(name);
        if (it != model->m_roleNames.end()) {
            roles.append(*it);
            QHash<int,QVariant> values = model->m_listModelInterface->data(data->m_index, QList<int>() << *it);
            if (values.isEmpty())
                return QVariant();
            else
                return values.value(*it);
        } else if (model->m_roles.count() == 1 && name == QLatin1String("modelData")) {
            //for compatability with other lists, assign modelData if there is only a single role
            QHash<int,QVariant> values = model->m_listModelInterface->data(data->m_index, QList<int>() << model->m_roles.first());
            if (values.isEmpty())
                return QVariant();
            else
                return *values.begin();
        }
    } else if (model->m_abstractItemModel) {
        model->ensureRoles();
        QHash<QString,int>::const_iterator it = model->m_roleNames.find(name);
        if (it != model->m_roleNames.end()) {
            roles.append(*it);
            QModelIndex index = model->m_abstractItemModel->index(data->m_index, 0);
            return model->m_abstractItemModel->data(index, *it);
        }
    }
    Q_ASSERT(!"Can never be reached");
    return QVariant();
}

QmlGraphicsVisualDataModelData::QmlGraphicsVisualDataModelData(int index,
                                               QmlGraphicsVisualDataModel *model)
: m_index(index), m_model(model), 
  m_meta(new QmlGraphicsVisualDataModelDataMetaObject(this))
{
}

QmlGraphicsVisualDataModelData::~QmlGraphicsVisualDataModelData()
{
}

int QmlGraphicsVisualDataModelData::index() const
{
    return m_index;
}

// This is internal only - it should not be set from qml
void QmlGraphicsVisualDataModelData::setIndex(int index)
{
    m_index = index;
    emit indexChanged();
}

class QmlGraphicsVisualDataModelPartsMetaObject : public QmlOpenMetaObject
{
public:
    QmlGraphicsVisualDataModelPartsMetaObject(QObject *parent)
    : QmlOpenMetaObject(parent) {}

    virtual QVariant propertyCreated(int, QMetaPropertyBuilder &);
};

class QmlGraphicsVisualDataModelParts : public QObject
{
Q_OBJECT
public:
    QmlGraphicsVisualDataModelParts(QmlGraphicsVisualDataModel *parent);

private:
    friend class QmlGraphicsVisualDataModelPartsMetaObject;
    QmlGraphicsVisualDataModel *model;
};

QVariant 
QmlGraphicsVisualDataModelPartsMetaObject::propertyCreated(int, QMetaPropertyBuilder &prop)
{
    prop.setWritable(false);

    QmlGraphicsVisualDataModel *m = new QmlGraphicsVisualDataModel;
    m->setParent(object());
    m->setPart(QString::fromUtf8(prop.name()));
    m->setModel(QVariant::fromValue(static_cast<QmlGraphicsVisualDataModelParts *>(object())->model));

    QVariant var = QVariant::fromValue((QObject *)m);
    return var;
}

QmlGraphicsVisualDataModelParts::QmlGraphicsVisualDataModelParts(QmlGraphicsVisualDataModel *parent)
: QObject(parent), model(parent) 
{
    new QmlGraphicsVisualDataModelPartsMetaObject(this);
}

QmlGraphicsVisualDataModelPrivate::QmlGraphicsVisualDataModelPrivate(QmlContext *ctxt)
: m_listModelInterface(0), m_abstractItemModel(0), m_visualItemModel(0), m_delegate(0)
, m_context(ctxt), m_parts(0), m_listAccessor(0)
{
}

QmlGraphicsVisualDataModelData *QmlGraphicsVisualDataModelPrivate::data(QObject *item)
{
    QmlGraphicsVisualDataModelData *dataItem =
        item->findChild<QmlGraphicsVisualDataModelData *>();
    Q_ASSERT(dataItem);
    return dataItem;
}

QmlGraphicsVisualDataModel::QmlGraphicsVisualDataModel()
: QmlGraphicsVisualModel(*(new QmlGraphicsVisualDataModelPrivate(0)))
{
}

QmlGraphicsVisualDataModel::QmlGraphicsVisualDataModel(QmlContext *ctxt)
: QmlGraphicsVisualModel(*(new QmlGraphicsVisualDataModelPrivate(ctxt)))
{
}

QmlGraphicsVisualDataModel::~QmlGraphicsVisualDataModel()
{
    Q_D(QmlGraphicsVisualDataModel);
    if (d->m_listAccessor)
        delete d->m_listAccessor;
}

QVariant QmlGraphicsVisualDataModel::model() const
{
    Q_D(const QmlGraphicsVisualDataModel);
    return d->m_modelVariant;
}

void QmlGraphicsVisualDataModel::setModel(const QVariant &model)
{
    Q_D(QmlGraphicsVisualDataModel);
    delete d->m_listAccessor;
    d->m_listAccessor = 0;
    d->m_modelVariant = model;
    if (d->m_listModelInterface) {
        // Assume caller has released all items.
        QObject::disconnect(d->m_listModelInterface, SIGNAL(itemsChanged(int,int,QList<int>)),
                this, SLOT(_q_itemsChanged(int,int,QList<int>)));
        QObject::disconnect(d->m_listModelInterface, SIGNAL(itemsInserted(int,int)),
                this, SLOT(_q_itemsInserted(int,int)));
        QObject::disconnect(d->m_listModelInterface, SIGNAL(itemsRemoved(int,int)),
                this, SLOT(_q_itemsRemoved(int,int)));
        QObject::disconnect(d->m_listModelInterface, SIGNAL(itemsMoved(int,int,int)),
                this, SLOT(_q_itemsMoved(int,int,int)));
        d->m_listModelInterface = 0;
    } else if (d->m_abstractItemModel) {
        QObject::disconnect(d->m_abstractItemModel, SIGNAL(rowsInserted(const QModelIndex &,int,int)),
                            this, SLOT(_q_rowsInserted(const QModelIndex &,int,int)));
        QObject::disconnect(d->m_abstractItemModel, SIGNAL(rowsRemoved(const QModelIndex &,int,int)),
                            this, SLOT(_q_rowsRemoved(const QModelIndex &,int,int)));
        QObject::disconnect(d->m_abstractItemModel, SIGNAL(dataChanged(const QModelIndex&,const QModelIndex&)),
                            this, SLOT(_q_dataChanged(const QModelIndex&,const QModelIndex&)));
        QObject::disconnect(d->m_abstractItemModel, SIGNAL(rowsMoved(const QModelIndex&,int,int,const QModelIndex&,int)),
                            this, SLOT(_q_rowsMoved(const QModelIndex&,int,int,const QModelIndex&,int)));
    } else if (d->m_visualItemModel) {
        QObject::disconnect(d->m_visualItemModel, SIGNAL(itemsInserted(int,int)),
                         this, SIGNAL(itemsInserted(int,int)));
        QObject::disconnect(d->m_visualItemModel, SIGNAL(itemsRemoved(int,int)),
                         this, SIGNAL(itemsRemoved(int,int)));
        QObject::disconnect(d->m_visualItemModel, SIGNAL(itemsMoved(int,int,int)),
                         this, SIGNAL(itemsMoved(int,int,int)));
        QObject::disconnect(d->m_visualItemModel, SIGNAL(createdPackage(int,QmlPackage*)),
                         this, SLOT(_q_createdPackage(int,QmlPackage*)));
        QObject::disconnect(d->m_visualItemModel, SIGNAL(destroyingPackage(QmlPackage*)),
                         this, SLOT(_q_destroyingPackage(QmlPackage*)));
        d->m_visualItemModel = 0;
    }

    d->m_roles.clear();
    d->m_roleNames.clear();

    QObject *object = qvariant_cast<QObject *>(model);
    if (object && (d->m_listModelInterface = qobject_cast<QListModelInterface *>(object))) {
        QObject::connect(d->m_listModelInterface, SIGNAL(itemsChanged(int,int,QList<int>)),
                         this, SLOT(_q_itemsChanged(int,int,QList<int>)));
        QObject::connect(d->m_listModelInterface, SIGNAL(itemsInserted(int,int)),
                         this, SLOT(_q_itemsInserted(int,int)));
        QObject::connect(d->m_listModelInterface, SIGNAL(itemsRemoved(int,int)),
                         this, SLOT(_q_itemsRemoved(int,int)));
        QObject::connect(d->m_listModelInterface, SIGNAL(itemsMoved(int,int,int)),
                         this, SLOT(_q_itemsMoved(int,int,int)));
        if (d->m_delegate && d->m_listModelInterface->count())
            emit itemsInserted(0, d->m_listModelInterface->count());
        return;
    } else if (object && (d->m_abstractItemModel = qobject_cast<QAbstractItemModel *>(object))) {
        QObject::connect(d->m_abstractItemModel, SIGNAL(rowsInserted(const QModelIndex &,int,int)),
                            this, SLOT(_q_rowsInserted(const QModelIndex &,int,int)));
        QObject::connect(d->m_abstractItemModel, SIGNAL(rowsRemoved(const QModelIndex &,int,int)),
                            this, SLOT(_q_rowsRemoved(const QModelIndex &,int,int)));
        QObject::connect(d->m_abstractItemModel, SIGNAL(dataChanged(const QModelIndex&,const QModelIndex&)),
                            this, SLOT(_q_dataChanged(const QModelIndex&,const QModelIndex&)));
        QObject::connect(d->m_abstractItemModel, SIGNAL(rowsMoved(const QModelIndex&,int,int,const QModelIndex&,int)),
                            this, SLOT(_q_rowsMoved(const QModelIndex&,int,int,const QModelIndex&,int)));
        return;
    }
    if ((d->m_visualItemModel = qvariant_cast<QmlGraphicsVisualDataModel *>(model))) {
        QObject::connect(d->m_visualItemModel, SIGNAL(itemsInserted(int,int)),
                         this, SIGNAL(itemsInserted(int,int)));
        QObject::connect(d->m_visualItemModel, SIGNAL(itemsRemoved(int,int)),
                         this, SIGNAL(itemsRemoved(int,int)));
        QObject::connect(d->m_visualItemModel, SIGNAL(itemsMoved(int,int,int)),
                         this, SIGNAL(itemsMoved(int,int,int)));
        QObject::connect(d->m_visualItemModel, SIGNAL(createdPackage(int,QmlPackage*)),
                         this, SLOT(_q_createdPackage(int,QmlPackage*)));
        QObject::connect(d->m_visualItemModel, SIGNAL(destroyingPackage(QmlPackage*)),
                         this, SLOT(_q_destroyingPackage(QmlPackage*)));
        return;
    }
    d->m_listAccessor = new QmlListAccessor;
    d->m_listAccessor->setList(model, d->m_context?d->m_context->engine():qmlEngine(this));
    if (d->m_delegate && d->modelCount()) {
        emit itemsInserted(0, d->modelCount());
        emit countChanged();
    }
}

QmlComponent *QmlGraphicsVisualDataModel::delegate() const
{
    Q_D(const QmlGraphicsVisualDataModel);
    if (d->m_visualItemModel)
        return d->m_visualItemModel->delegate();
    return d->m_delegate;
}

void QmlGraphicsVisualDataModel::setDelegate(QmlComponent *delegate)
{
    Q_D(QmlGraphicsVisualDataModel);
    d->m_delegate = delegate;
    if (d->modelCount()) {
        emit itemsInserted(0, d->modelCount());
        emit countChanged();
    }
}

QString QmlGraphicsVisualDataModel::part() const
{
    Q_D(const QmlGraphicsVisualDataModel);
    return d->m_part;
}

void QmlGraphicsVisualDataModel::setPart(const QString &part)
{
    Q_D(QmlGraphicsVisualDataModel);
    d->m_part = part;
}

int QmlGraphicsVisualDataModel::count() const
{
    Q_D(const QmlGraphicsVisualDataModel);
    return d->modelCount();
}

QmlGraphicsItem *QmlGraphicsVisualDataModel::item(int index, bool complete)
{
    Q_D(QmlGraphicsVisualDataModel);
    if (d->m_visualItemModel)
        return d->m_visualItemModel->item(index, d->m_part.toUtf8(), complete);
    return item(index, QByteArray(), complete);
}

/*
  Returns ReleaseStatus flags.
*/
QmlGraphicsVisualDataModel::ReleaseFlags QmlGraphicsVisualDataModel::release(QmlGraphicsItem *item)
{
    Q_D(QmlGraphicsVisualDataModel);
    if (d->m_visualItemModel)
        return d->m_visualItemModel->release(item);

    ReleaseFlags stat = 0;
    QObject *obj = item;
    bool inPackage = false;

    QHash<QObject*,QmlPackage*>::iterator it = d->m_packaged.find(item);
    if (it != d->m_packaged.end()) {
        QmlPackage *package = *it;
        d->m_packaged.erase(it);
        if (d->m_packaged.contains(item))
            stat |= Referenced;
        inPackage = true;
        obj = package; // fall through and delete
    }

    if (d->m_cache.releaseItem(obj)) {
        if (inPackage)
            emit destroyingPackage(qobject_cast<QmlPackage*>(obj));
        stat |= Destroyed;
        obj->setParent(0);
        obj->deleteLater();
    } else if (!inPackage) {
        stat |= Referenced;
    }

    return stat;
}

QObject *QmlGraphicsVisualDataModel::parts()
{
    Q_D(QmlGraphicsVisualDataModel);
    if (!d->m_parts) 
        d->m_parts = new QmlGraphicsVisualDataModelParts(this);
    return d->m_parts;
}

QmlGraphicsItem *QmlGraphicsVisualDataModel::item(int index, const QByteArray &viewId, bool complete)
{
    Q_D(QmlGraphicsVisualDataModel);
    if (d->m_visualItemModel)
        return d->m_visualItemModel->item(index, viewId, complete);

    if (d->modelCount() <= 0 || !d->m_delegate)
        return 0;

    QObject *nobj = d->m_cache.getItem(index);
    if (!nobj) {
        QmlContext *ccontext = d->m_context;
        if (!ccontext) ccontext = qmlContext(this);
        QmlContext *ctxt = new QmlContext(ccontext);
        QmlGraphicsVisualDataModelData *data = new QmlGraphicsVisualDataModelData(index, this);
        ctxt->setContextProperty(QLatin1String("model"), data);
        ctxt->addDefaultObject(data);
        nobj = d->m_delegate->beginCreate(ctxt);
        if (complete)
            d->m_delegate->completeCreate();
        if (nobj) {
            ctxt->setParent(nobj);
            data->setParent(nobj);
            d->m_cache.insertItem(index, nobj);
            if (QmlPackage *package = qobject_cast<QmlPackage *>(nobj))
                emit createdPackage(index, package);
        } else {
            delete data;
            delete ctxt;
            qWarning() << d->m_delegate->errors();
        }
    }
    QmlGraphicsItem *item = qobject_cast<QmlGraphicsItem *>(nobj);
    if (!item) {
        QmlPackage *package = qobject_cast<QmlPackage *>(nobj);
        if (package) {
            QObject *o = package->part(QString::fromUtf8(viewId));
            item = qobject_cast<QmlGraphicsItem *>(o);
            if (item)
                d->m_packaged.insertMulti(item, package);
        }
    }
    if (!item) {
        d->m_cache.releaseItem(nobj);
        qmlInfo(d->m_delegate) << QmlGraphicsVisualDataModel::tr("Delegate component must be Item type.");
    }

    return item;
}

void QmlGraphicsVisualDataModel::completeItem()
{
    Q_D(QmlGraphicsVisualDataModel);
    if (d->m_visualItemModel) {
        d->m_visualItemModel->completeItem();
        return;
    }

    d->m_delegate->completeCreate();
}

QVariant QmlGraphicsVisualDataModel::evaluate(int index, const QString &expression, QObject *objectContext)
{
    Q_D(QmlGraphicsVisualDataModel);
    if (d->m_visualItemModel)
        return d->m_visualItemModel->evaluate(index, expression, objectContext);

    if ((!d->m_listModelInterface && !d->m_abstractItemModel) || !d->m_delegate)
        return QVariant();

    QVariant value;
    QObject *nobj = d->m_cache.item(index);
    if (nobj) {
        QmlGraphicsItem *item = qobject_cast<QmlGraphicsItem *>(nobj);
        if (item) {
            QmlExpression e(qmlContext(item), expression, objectContext);
            e.setTrackChange(false);
            value = e.value();
        }
    } else {
        QmlContext *ccontext = d->m_context;
        if (!ccontext) ccontext = qmlContext(this);
        QmlContext *ctxt = new QmlContext(ccontext);
        QmlGraphicsVisualDataModelData *data = new QmlGraphicsVisualDataModelData(index, this);
        ctxt->addDefaultObject(data);
        QmlExpression e(ctxt, expression, objectContext);
        e.setTrackChange(false);
        value = e.value();
        delete data;
        delete ctxt;
    }

    return value;
}

int QmlGraphicsVisualDataModel::indexOf(QmlGraphicsItem *item, QObject *objectContext) const
{
    QmlExpression e(qmlContext(item), QLatin1String("index"), objectContext);
    e.setTrackChange(false);
    QVariant value = e.value();
    if (value.isValid())
        return value.toInt();
    return -1;
}

void QmlGraphicsVisualDataModel::_q_itemsChanged(int index, int count,
                                         const QList<int> &roles)
{
    Q_D(QmlGraphicsVisualDataModel);
    // XXX - highly inefficient
    for (int ii = index; ii < index + count; ++ii) {

        if (QObject *item = d->m_cache.item(ii)) {
            QmlGraphicsVisualDataModelData *data = d->data(item);

            for (int prop = 0; prop < data->count(); ++prop) {

                int role = data->role(prop);
                if (roles.contains(role)) {
                    if (d->m_listModelInterface) {
                        data->setValue(prop, d->m_listModelInterface->data(ii, QList<int>() << role).value(role));
                    } else if (d->m_abstractItemModel) {
                        QModelIndex index = d->m_abstractItemModel->index(ii, 0);
                        data->setValue(prop, d->m_abstractItemModel->data(index, role));
                    }
                }
            }
        }

    }
}

void QmlGraphicsVisualDataModel::_q_itemsInserted(int index, int count)
{
    Q_D(QmlGraphicsVisualDataModel);
    // XXX - highly inefficient
    QHash<int,QmlGraphicsVisualDataModelPrivate::ObjectRef> items;
    for (QHash<int,QmlGraphicsVisualDataModelPrivate::ObjectRef>::Iterator iter = d->m_cache.begin();
        iter != d->m_cache.end(); ) {

        if (iter.key() >= index) {
            QmlGraphicsVisualDataModelPrivate::ObjectRef objRef = *iter;
            int index = iter.key() + count;
            iter = d->m_cache.erase(iter);

            items.insert(index, objRef);

            QmlGraphicsVisualDataModelData *data = d->data(objRef.obj);
            data->setIndex(index);
        } else {
            ++iter;
        }
    }
    d->m_cache.unite(items);

    emit itemsInserted(index, count);
    emit countChanged();
}

void QmlGraphicsVisualDataModel::_q_itemsRemoved(int index, int count)
{
    Q_D(QmlGraphicsVisualDataModel);
    // XXX - highly inefficient
    QHash<int, QmlGraphicsVisualDataModelPrivate::ObjectRef> items;
    for (QHash<int, QmlGraphicsVisualDataModelPrivate::ObjectRef>::Iterator iter = d->m_cache.begin();
        iter != d->m_cache.end(); ) {
        if (iter.key() >= index && iter.key() < index + count) {
            QmlGraphicsVisualDataModelPrivate::ObjectRef objRef = *iter;
            iter = d->m_cache.erase(iter);
            items.insertMulti(-1, objRef); //XXX perhaps better to maintain separately
            QmlGraphicsVisualDataModelData *data = d->data(objRef.obj);
            data->setIndex(-1);
        } else if (iter.key() >= index + count) {
            QmlGraphicsVisualDataModelPrivate::ObjectRef objRef = *iter;
            int index = iter.key() - count;
            iter = d->m_cache.erase(iter);
            items.insert(index, objRef);
            QmlGraphicsVisualDataModelData *data = d->data(objRef.obj);
            data->setIndex(index);
        } else {
            ++iter;
        }
    }

    d->m_cache.unite(items);
    emit itemsRemoved(index, count);
    emit countChanged();
}

void QmlGraphicsVisualDataModel::_q_itemsMoved(int from, int to, int count)
{
    Q_D(QmlGraphicsVisualDataModel);
    // XXX - highly inefficient
    QHash<int,QmlGraphicsVisualDataModelPrivate::ObjectRef> items;
    for (QHash<int,QmlGraphicsVisualDataModelPrivate::ObjectRef>::Iterator iter = d->m_cache.begin();
        iter != d->m_cache.end(); ) {

        if (iter.key() >= from && iter.key() < from + count) {
            QmlGraphicsVisualDataModelPrivate::ObjectRef objRef = *iter;
            int index = iter.key() - from + to;
            iter = d->m_cache.erase(iter);

            items.insert(index, objRef);

            QmlGraphicsVisualDataModelData *data = d->data(objRef.obj);
            data->setIndex(index);
        } else {
            ++iter;
        }
    }
    for (QHash<int,QmlGraphicsVisualDataModelPrivate::ObjectRef>::Iterator iter = d->m_cache.begin();
        iter != d->m_cache.end(); ) {

        int diff = from > to ? count : -count;
        if (iter.key() >= qMin(from,to) && iter.key() < qMax(from+count,to+count)) {
            QmlGraphicsVisualDataModelPrivate::ObjectRef objRef = *iter;
            int index = iter.key() + diff;
            iter = d->m_cache.erase(iter);

            items.insert(index, objRef);

            QmlGraphicsVisualDataModelData *data = d->data(objRef.obj);
            data->setIndex(index);
        } else {
            ++iter;
        }
    }
    d->m_cache.unite(items);

    emit itemsMoved(from, to, count);
}

void QmlGraphicsVisualDataModel::_q_rowsInserted(const QModelIndex &parent, int begin, int end)
{
    if (!parent.isValid())
        _q_itemsInserted(begin, end - begin + 1);
}

void QmlGraphicsVisualDataModel::_q_rowsRemoved(const QModelIndex &parent, int begin, int end)
{
    if (!parent.isValid())
        _q_itemsRemoved(begin, end - begin + 1);
}

void QmlGraphicsVisualDataModel::_q_rowsMoved(const QModelIndex &sourceParent, int sourceStart, int sourceEnd, const QModelIndex &destinationParent, int destinationRow)
{
    const int count = sourceEnd - sourceStart + 1;
    if (!destinationParent.isValid() && !sourceParent.isValid()) {
        _q_itemsMoved(sourceStart, destinationRow, count);
    } else if (!sourceParent.isValid()) {
        _q_itemsRemoved(sourceStart, count);
    } else if (!destinationParent.isValid()) {
        _q_itemsInserted(destinationRow, count);
    }
}

void QmlGraphicsVisualDataModel::_q_dataChanged(const QModelIndex &begin, const QModelIndex &end)
{
    Q_D(QmlGraphicsVisualDataModel);
    if (!begin.parent().isValid())
        _q_itemsChanged(begin.row(), end.row() - begin.row() + 1, d->m_roles);
}

void QmlGraphicsVisualDataModel::_q_createdPackage(int index, QmlPackage *package)
{
    Q_D(QmlGraphicsVisualDataModel);
    emit createdItem(index, qobject_cast<QmlGraphicsItem*>(package->part(d->m_part)));
}

void QmlGraphicsVisualDataModel::_q_destroyingPackage(QmlPackage *package)
{
    Q_D(QmlGraphicsVisualDataModel);
    emit destroyingItem(qobject_cast<QmlGraphicsItem*>(package->part(d->m_part)));
}

QML_DEFINE_NOCREATE_TYPE(QmlGraphicsVisualModel);
QML_DEFINE_TYPE(Qt,4,6,VisualItemModel,QmlGraphicsVisualItemModel)
QML_DEFINE_TYPE(Qt,4,6,VisualDataModel,QmlGraphicsVisualDataModel)

QT_END_NAMESPACE

#include "qmlgraphicsvisualitemmodel.moc"