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#include "private/qdeclarativerepeater_p.h"

#include "private/qdeclarativerepeater_p_p.h"

#include "private/qdeclarativevisualitemmodel_p.h"

#include <private/qdeclarativeglobal_p.h>

#include <qdeclarativelistaccessor_p.h>

#include <qlistmodelinterface_p.h>

QT_BEGIN_NAMESPACE

QDeclarativeRepeaterPrivate::QDeclarativeRepeaterPrivate()

: model(0), ownModel(false)

{

}

QDeclarativeRepeaterPrivate::~QDeclarativeRepeaterPrivate()

{

    if (ownModel)

        delete model;

}

/*!

    \qmlclass Repeater QDeclarativeRepeater

    \since 4.7

    \inherits Item

    \brief The Repeater item allows you to repeat an Item-based component using a model.

    The Repeater item is used to create a large number of

    similar items.  For each entry in the model, an item is instantiated

    in a context seeded with data from the model.  If the repeater will

    be instantiating a large number of instances, it may be more efficient to

    use one of Qt Declarative's \l {xmlViews}{view items}.

    The model may be either an object list, a string list, a number or a Qt model.

    In each case, the data element and the index is exposed to each instantiated

    component.  

    The index is always exposed as an accessible \c index property.

    In the case of an object or string list, the data element (of type string

    or object) is available as the \c modelData property.  In the case of a Qt model,

    all roles are available as named properties just like in the view classes. The

    following example shows how to use the index property inside the instantiated

    items.

    \snippet doc/src/snippets/declarative/repeater-index.qml 0

    \image repeater-index.png

    Items instantiated by the Repeater are inserted, in order, as

    children of the Repeater's parent.  The insertion starts immediately after

    the repeater's position in its parent stacking list.  This is to allow

    you to use a Repeater inside a layout.  The following QML example shows how

    the instantiated items would visually appear stacked between the red and

    blue rectangles.

    \snippet doc/src/snippets/declarative/repeater.qml 0

    \image repeater.png

    The repeater instance continues to own all items it instantiates, even

    if they are otherwise manipulated.  It is illegal to manually remove an item

    created by the Repeater.

    \note Repeater is Item-based, and cannot be used to repeat non-Item-derived objects.

    For example, it cannot be used to repeat QtObjects.

    \badcode

    Item {

        //XXX illegal. Can't repeat QtObject as it doesn't derive from Item.

        Repeater {

            model: 10

            QtObject {}

        }

    }

    \endcode

 */

/*!

    \internal

    \class QDeclarativeRepeater

    \qmlclass Repeater

 */

/*!

    Create a new QDeclarativeRepeater instance.

 */

QDeclarativeRepeater::QDeclarativeRepeater(QDeclarativeItem *parent)

  : QDeclarativeItem(*(new QDeclarativeRepeaterPrivate), parent)

{

}

/*!

    Destroy the repeater instance.  All items it instantiated are also

    destroyed.

 */

QDeclarativeRepeater::~QDeclarativeRepeater()

{

}

/*!

    \qmlproperty any Repeater::model

    The model providing data for the repeater.

    The model may be either an object list, a string list, a number or a Qt model.

    In each case, the data element and the index is exposed to each instantiated

    component.  The index is always exposed as an accessible \c index property.

    In the case of an object or string list, the data element (of type string

    or object) is available as the \c modelData property.  In the case of a Qt model,

    all roles are available as named properties just like in the view classes.

    As a special case the model can also be merely a number. In this case it will

    create that many instances of the component. They will also be assigned an index

    based on the order they are created.

    Models can also be created directly in QML, using a \l{ListModel} or \l{XmlListModel}.

    \sa {qmlmodels}{Data Models}

*/

QVariant QDeclarativeRepeater::model() const

{

    Q_D(const QDeclarativeRepeater);

    return d->dataSource;

}

void QDeclarativeRepeater::setModel(const QVariant &model)

{

    Q_D(QDeclarativeRepeater);

    if (d->dataSource == model)

        return;

    clear();

    if (d->model) {

        disconnect(d->model, SIGNAL(itemsInserted(int,int)), this, SLOT(itemsInserted(int,int)));

        disconnect(d->model, SIGNAL(itemsRemoved(int,int)), this, SLOT(itemsRemoved(int,int)));

        disconnect(d->model, SIGNAL(itemsMoved(int,int,int)), this, SLOT(itemsMoved(int,int,int)));

        disconnect(d->model, SIGNAL(modelReset()), this, SLOT(modelReset()));

        /*

        disconnect(d->model, SIGNAL(createdItem(int, QDeclarativeItem*)), this, SLOT(createdItem(int,QDeclarativeItem*)));

        disconnect(d->model, SIGNAL(destroyingItem(QDeclarativeItem*)), this, SLOT(destroyingItem(QDeclarativeItem*)));

    */

    }

    d->dataSource = model;

    emit modelChanged();

    QObject *object = qvariant_cast<QObject*>(model);

    QDeclarativeVisualModel *vim = 0;

    if (object && (vim = qobject_cast<QDeclarativeVisualModel *>(object))) {

        if (d->ownModel) {

            delete d->model;

            d->ownModel = false;

        }

        d->model = vim;

    } else {

        if (!d->ownModel) {

            d->model = new QDeclarativeVisualDataModel(qmlContext(this), this);

            d->ownModel = true;

        }

        if (QDeclarativeVisualDataModel *dataModel = qobject_cast<QDeclarativeVisualDataModel*>(d->model))

            dataModel->setModel(model);

    }

    if (d->model) {

        connect(d->model, SIGNAL(itemsInserted(int,int)), this, SLOT(itemsInserted(int,int)));

        connect(d->model, SIGNAL(itemsRemoved(int,int)), this, SLOT(itemsRemoved(int,int)));

        connect(d->model, SIGNAL(itemsMoved(int,int,int)), this, SLOT(itemsMoved(int,int,int)));

        connect(d->model, SIGNAL(modelReset()), this, SLOT(modelReset()));

        /*

        connect(d->model, SIGNAL(createdItem(int, QDeclarativeItem*)), this, SLOT(createdItem(int,QDeclarativeItem*)));

        connect(d->model, SIGNAL(destroyingItem(QDeclarativeItem*)), this, SLOT(destroyingItem(QDeclarativeItem*)));

        */

        regenerate();

        emit countChanged();

    }

}

/*!

    \qmlproperty Component Repeater::delegate

    \default

    The delegate provides a template defining each item instantiated by the repeater.

    The index is exposed as an accessible \c index property.  Properties of the

    model are also available depending upon the type of \l {qmlmodels}{Data Model}.

 */

QDeclarativeComponent *QDeclarativeRepeater::delegate() const

{

    Q_D(const QDeclarativeRepeater);

    if (d->model) {

        if (QDeclarativeVisualDataModel *dataModel = qobject_cast<QDeclarativeVisualDataModel*>(d->model))

            return dataModel->delegate();

    }

    return 0;

}

void QDeclarativeRepeater::setDelegate(QDeclarativeComponent *delegate)

{

    Q_D(QDeclarativeRepeater);

    if (QDeclarativeVisualDataModel *dataModel = qobject_cast<QDeclarativeVisualDataModel*>(d->model))

       if (delegate == dataModel->delegate())

           return;

    if (!d->ownModel) {

        d->model = new QDeclarativeVisualDataModel(qmlContext(this));

        d->ownModel = true;

    }

    if (QDeclarativeVisualDataModel *dataModel = qobject_cast<QDeclarativeVisualDataModel*>(d->model)) {

        dataModel->setDelegate(delegate);

        regenerate();

        emit delegateChanged();

    }

}

/*!

    \qmlproperty int Repeater::count

    This property holds the number of items in the repeater.

*/

int QDeclarativeRepeater::count() const

{

    Q_D(const QDeclarativeRepeater);

    if (d->model)

        return d->model->count();

    return 0;

}

/*!

    \internal

 */

void QDeclarativeRepeater::componentComplete()

{

    QDeclarativeItem::componentComplete();

    regenerate();

}

/*!

    \internal

 */

QVariant QDeclarativeRepeater::itemChange(GraphicsItemChange change,

                                       const QVariant &value)

{

    QVariant rv = QDeclarativeItem::itemChange(change, value);

    if (change == ItemParentHasChanged) {

        regenerate();

    }

    return rv;

}

void QDeclarativeRepeater::clear()

{

    Q_D(QDeclarativeRepeater);

    if (d->model) {

        foreach (QDeclarativeItem *item, d->deletables) {

            d->model->release(item);

        }

    }

    d->deletables.clear();

}

/*!

    \internal

 */

void QDeclarativeRepeater::regenerate()

{

    Q_D(QDeclarativeRepeater);

    if (!isComponentComplete())

        return;

    clear();

    if (!d->model || !d->model->count() || !d->model->isValid() || !parentItem() || !isComponentComplete())

        return;

    for (int ii = 0; ii < count(); ++ii) {

        QDeclarativeItem *item = d->model->item(ii);

        if (item) {

            QDeclarative_setParent_noEvent(item, parentItem());

            item->setParentItem(parentItem());

            item->stackBefore(this);

            d->deletables << item;

        }

    }

}

void QDeclarativeRepeater::itemsInserted(int index, int count)

{

    Q_D(QDeclarativeRepeater);

    if (!isComponentComplete())

        return;

    for (int i = 0; i < count; ++i) {

        int modelIndex = index + i;

        QDeclarativeItem *item = d->model->item(modelIndex);

        if (item) {

            QDeclarative_setParent_noEvent(item, parentItem());

            item->setParentItem(parentItem());

            if (modelIndex < d->deletables.count())

                item->stackBefore(d->deletables.at(modelIndex));

            else

                item->stackBefore(this);

            d->deletables.insert(modelIndex, item);

        }

    }

}

void QDeclarativeRepeater::itemsRemoved(int index, int count)

{

    Q_D(QDeclarativeRepeater);

    if (!isComponentComplete() || count <= 0)

        return;

    while (count--) {

        QDeclarativeItem *item = d->deletables.takeAt(index);

        if (item)

            d->model->release(item);

        else

            break;

    }

}

void QDeclarativeRepeater::itemsMoved(int from, int to, int count)

{

    Q_D(QDeclarativeRepeater);

    if (!isComponentComplete() || count <= 0)

        return;

    if (from + count > d->deletables.count()) {

        regenerate();

        return;

    }

    QList<QDeclarativeItem*> removed;

    int removedCount = count;

    while (removedCount--)

        removed << d->deletables.takeAt(from);

    for (int i = 0; i < count; ++i)

        d->deletables.insert(to + i, removed.at(i));

    d->deletables.last()->stackBefore(this);

    for (int i = d->model->count()-1; i > 0; --i) {

        QDeclarativeItem *item = d->deletables.at(i-1);

        item->stackBefore(d->deletables.at(i));

    }

}

void QDeclarativeRepeater::modelReset()

{

    if (!isComponentComplete())

        return;

    regenerate();

}

QT_END_NAMESPACE