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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 element allows you to repeat an Item-based component using a model.

    The Repeater element is used to create a large number of

    similar items. Like other view elements, a Repeater has a \l model and a \l delegate:

    for each entry in the model, the delegate is instantiated

    in a context seeded with data from the model. A Repeater item is usually

    enclosed in a positioner element such as \l Row or \l Column to visually

    position the multiple delegate items created by the Repeater.

    The following Repeater creates three instances of a \l Rectangle item within

    a \l Row:

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

    \codeline

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

    \image repeater-simple.png

    The \l model of a Repeater can be any of the supported \l {qmlmodels}{Data Models}.

    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 allows

    a Repeater to be used inside a layout. For example, the following Repeater's

    items are stacked between a red rectangle and a blue rectangle:

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

    \image repeater.png

    \section2 The \c index and \c modelData properties

    The index of a delegate is exposed as an accessible \c index property in the delegate.

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

    Here is a Repeater that uses the \c index property inside the instantiated items:

    \table

    \row

    \o \snippet doc/src/snippets/declarative/repeater.qml index

    \o \image repeater-index.png

    \endtable

    Here is another Repeater that uses the \c modelData property to reference the data for a

    particular index:

    \table

    \row

    \o \snippet doc/src/snippets/declarative/repeater.qml modeldata

    \o \image repeater-modeldata.png

    \endtable

    A Repeater item owns all items it instantiates. Removing or dynamically destroying

    an item created by a Repeater results in unpredictable behavior.

    \section2 Considerations when using Repeater

    The Repeater element creates all of its delegate items when the repeater is first

    created. This can be inefficient if there are a large number of delegate items and

    not all of the items are required to be visible at the same time. If this is the case,

    consider using other view elements like ListView (which only creates delegate items 

    when they are scrolled into view) or use the \l {Dynamic Object Creation} methods to 

    create items as they are required.

    Also, note that Repeater is \l {Item}-based, and can only repeat \l {Item}-derived objects. 

    \badcode

    Item {

        Repeater {

            model: 10

        }

    }

    \endcode

 */

QDeclarativeRepeater::QDeclarativeRepeater(QDeclarativeItem *parent)

  : QDeclarativeItem(*(new QDeclarativeRepeaterPrivate), parent)

{

}

QDeclarativeRepeater::~QDeclarativeRepeater()

{

}

/*!

    \qmlproperty any Repeater::model

    The model providing data for the repeater.

    This property can be set to any of the following:

    \list

    \o A number that indicates the number of delegates to be created

    \o A model (e.g. a ListModel item, or a QAbstractItemModel subclass)

    \o A string list

    \o An object list

    \endlist

    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();

    }

}

/*!

    \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;

}

void QDeclarativeRepeater::componentComplete()

{

    QDeclarativeItem::componentComplete();

    regenerate();

}

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();

}

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