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#include "private/qdeclarativestateoperations_p.h"

#include <qdeclarative.h>

#include <qdeclarativecontext.h>

#include <qdeclarativeexpression.h>

#include <qdeclarativeinfo.h>

#include <qdeclarativeanchors_p_p.h>

#include <qdeclarativeitem_p.h>

#include <qdeclarativeguard_p.h>

#include <qdeclarativenullablevalue_p_p.h>

#include "private/qdeclarativecontext_p.h"

#include "private/qdeclarativeproperty_p.h"

#include "private/qdeclarativebinding_p.h"

#include <QtCore/qdebug.h>

#include <QtGui/qgraphicsitem.h>

#include <QtCore/qmath.h>

#include <private/qobject_p.h>

QT_BEGIN_NAMESPACE

class QDeclarativeParentChangePrivate : public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QDeclarativeParentChange)

public:

    QDeclarativeParentChangePrivate() : target(0), parent(0), origParent(0), origStackBefore(0),

        rewindParent(0), rewindStackBefore(0) {}

    QDeclarativeItem *target;

    QDeclarativeGuard<QDeclarativeItem> parent;

    QDeclarativeGuard<QDeclarativeItem> origParent;

    QDeclarativeGuard<QDeclarativeItem> origStackBefore;

    QDeclarativeItem *rewindParent;

    QDeclarativeItem *rewindStackBefore;

    QDeclarativeNullableValue<QDeclarativeScriptString> xString;

    QDeclarativeNullableValue<QDeclarativeScriptString> yString;

    QDeclarativeNullableValue<QDeclarativeScriptString> widthString;

    QDeclarativeNullableValue<QDeclarativeScriptString> heightString;

    QDeclarativeNullableValue<QDeclarativeScriptString> scaleString;

    QDeclarativeNullableValue<QDeclarativeScriptString> rotationString;

    void doChange(QDeclarativeItem *targetParent, QDeclarativeItem *stackBefore = 0);

};

void QDeclarativeParentChangePrivate::doChange(QDeclarativeItem *targetParent, QDeclarativeItem *stackBefore)

{

    if (targetParent && target && target->parentItem()) {

        Q_Q(QDeclarativeParentChange);

        bool ok;

        const QTransform &transform = target->parentItem()->itemTransform(targetParent, &ok);

        if (transform.type() >= QTransform::TxShear || !ok) {

            qmlInfo(q) << QDeclarativeParentChange::tr("Unable to preserve appearance under complex transform");

            ok = false;

        }

        qreal scale = 1;

        qreal rotation = 0;

        if (ok && transform.type() != QTransform::TxRotate) {

            if (transform.m11() == transform.m22())

                scale = transform.m11();

            else {

                qmlInfo(q) << QDeclarativeParentChange::tr("Unable to preserve appearance under non-uniform scale");

                ok = false;

            }

        } else if (ok && transform.type() == QTransform::TxRotate) {

            if (transform.m11() == transform.m22())

                scale = qSqrt(transform.m11()*transform.m11() + transform.m12()*transform.m12());

            else {

                qmlInfo(q) << QDeclarativeParentChange::tr("Unable to preserve appearance under non-uniform scale");

                ok = false;

            }

            if (scale != 0)

                rotation = atan2(transform.m12()/scale, transform.m11()/scale) * 180/M_PI;

            else {

                qmlInfo(q) << QDeclarativeParentChange::tr("Unable to preserve appearance under scale of 0");

                ok = false;

            }

        }

        const QPointF &point = transform.map(QPointF(target->x(),target->y()));

        qreal x = point.x();

        qreal y = point.y();

        // setParentItem will update the transformOriginPoint if needed

        target->setParentItem(targetParent);

        if (ok && target->transformOrigin() != QDeclarativeItem::TopLeft) {

            qreal tempxt = target->transformOriginPoint().x();

            qreal tempyt = target->transformOriginPoint().y();

            QTransform t;

            t.translate(-tempxt, -tempyt);

            t.rotate(rotation);

            t.scale(scale, scale);

            t.translate(tempxt, tempyt);

            const QPointF &offset = t.map(QPointF(0,0));

            x += offset.x();

            y += offset.y();

        }

        if (ok) {

            //qDebug() << x << y << rotation << scale;

            target->setX(x);

            target->setY(y);

            target->setRotation(target->rotation() + rotation);

            target->setScale(target->scale() * scale);

        }

    } else if (target) {

        target->setParentItem(targetParent);

    }

    //restore the original stack position.

    //### if stackBefore has also been reparented this won't work

    if (stackBefore)

        target->stackBefore(stackBefore);

}

/*!

    \preliminary

    \qmlclass ParentChange QDeclarativeParentChange

    \brief The ParentChange element allows you to reparent an Item in a state change.

    ParentChange reparents an item while preserving its visual appearance (position, size,

    rotation, and scale) on screen. You can then specify a transition to move/resize/rotate/scale

    the item to its final intended appearance.

    ParentChange can only preserve visual appearance if no complex transforms are involved.

    More specifically, it will not work if the transform property has been set for any

    items involved in the reparenting (i.e. items in the common ancestor tree

    for the original and new parent).

    The example below displays a large red rectangle and a small blue rectangle, side by side. 

    When the \c blueRect is clicked, it changes to the "reparented" state: its parent is changed to \c redRect and it is 

    positioned at (10, 10) within the red rectangle, as specified in the ParentChange.

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

    \image parentchange.png

    You can specify at which point in a transition you want a ParentChange to occur by

    using a ParentAnimation.

*/

QDeclarativeParentChange::QDeclarativeParentChange(QObject *parent)

    : QDeclarativeStateOperation(*(new QDeclarativeParentChangePrivate), parent)

{

}

QDeclarativeParentChange::~QDeclarativeParentChange()

{

}

/*!

    \qmlproperty real ParentChange::x

    \qmlproperty real ParentChange::y

    \qmlproperty real ParentChange::width

    \qmlproperty real ParentChange::height

    \qmlproperty real ParentChange::scale

    \qmlproperty real ParentChange::rotation

    These properties hold the new position, size, scale, and rotation

    for the item in this state.

*/

QDeclarativeScriptString QDeclarativeParentChange::x() const

{

    Q_D(const QDeclarativeParentChange);

    return d->xString.value;

}

void QDeclarativeParentChange::setX(QDeclarativeScriptString x)

{

    Q_D(QDeclarativeParentChange);

    d->xString = x;

}

bool QDeclarativeParentChange::xIsSet() const

{

    Q_D(const QDeclarativeParentChange);

    return d->xString.isValid();

}

QDeclarativeScriptString QDeclarativeParentChange::y() const

{

    Q_D(const QDeclarativeParentChange);

    return d->yString.value;

}

void QDeclarativeParentChange::setY(QDeclarativeScriptString y)

{

    Q_D(QDeclarativeParentChange);

    d->yString = y;

}

bool QDeclarativeParentChange::yIsSet() const

{

    Q_D(const QDeclarativeParentChange);

    return d->yString.isValid();

}

QDeclarativeScriptString QDeclarativeParentChange::width() const

{

    Q_D(const QDeclarativeParentChange);

    return d->widthString.value;

}

void QDeclarativeParentChange::setWidth(QDeclarativeScriptString width)

{

    Q_D(QDeclarativeParentChange);

    d->widthString = width;

}

bool QDeclarativeParentChange::widthIsSet() const

{

    Q_D(const QDeclarativeParentChange);

    return d->widthString.isValid();

}

QDeclarativeScriptString QDeclarativeParentChange::height() const

{

    Q_D(const QDeclarativeParentChange);

    return d->heightString.value;

}

void QDeclarativeParentChange::setHeight(QDeclarativeScriptString height)

{

    Q_D(QDeclarativeParentChange);

    d->heightString = height;

}

bool QDeclarativeParentChange::heightIsSet() const

{

    Q_D(const QDeclarativeParentChange);

    return d->heightString.isValid();

}

QDeclarativeScriptString QDeclarativeParentChange::scale() const

{

    Q_D(const QDeclarativeParentChange);

    return d->scaleString.value;

}

void QDeclarativeParentChange::setScale(QDeclarativeScriptString scale)

{

    Q_D(QDeclarativeParentChange);

    d->scaleString = scale;

}

bool QDeclarativeParentChange::scaleIsSet() const

{

    Q_D(const QDeclarativeParentChange);

    return d->scaleString.isValid();

}

QDeclarativeScriptString QDeclarativeParentChange::rotation() const

{

    Q_D(const QDeclarativeParentChange);

    return d->rotationString.value;

}

void QDeclarativeParentChange::setRotation(QDeclarativeScriptString rotation)

{

    Q_D(QDeclarativeParentChange);

    d->rotationString = rotation;

}

bool QDeclarativeParentChange::rotationIsSet() const

{

    Q_D(const QDeclarativeParentChange);

    return d->rotationString.isValid();

}

QDeclarativeItem *QDeclarativeParentChange::originalParent() const

{

    Q_D(const QDeclarativeParentChange);

    return d->origParent;

}

/*!

    \qmlproperty Item ParentChange::target

    This property holds the item to be reparented

*/

QDeclarativeItem *QDeclarativeParentChange::object() const

{

    Q_D(const QDeclarativeParentChange);

    return d->target;

}

void QDeclarativeParentChange::setObject(QDeclarativeItem *target)

{

    Q_D(QDeclarativeParentChange);

    d->target = target;

}

/*!

    \qmlproperty Item ParentChange::parent

    This property holds the new parent for the item in this state.

*/

QDeclarativeItem *QDeclarativeParentChange::parent() const

{

    Q_D(const QDeclarativeParentChange);

    return d->parent;

}

void QDeclarativeParentChange::setParent(QDeclarativeItem *parent)

{

    Q_D(QDeclarativeParentChange);

    d->parent = parent;

}

QDeclarativeStateOperation::ActionList QDeclarativeParentChange::actions()

{

    Q_D(QDeclarativeParentChange);

    if (!d->target || !d->parent)

        return ActionList();

    ActionList actions;

    QDeclarativeAction a;

    a.event = this;

    actions << a;

    if (d->xString.isValid()) {

        bool ok = false;

        QString script = d->xString.value.script();

        qreal x = script.toFloat(&ok);

        if (ok) {

            QDeclarativeAction xa(d->target, QLatin1String("x"), x);

            actions << xa;

        } else {

            QDeclarativeBinding *newBinding = new QDeclarativeBinding(script, d->target, qmlContext(this));

            newBinding->setTarget(QDeclarativeProperty(d->target, QLatin1String("x")));

            QDeclarativeAction xa;

            xa.property = newBinding->property();

            xa.toBinding = newBinding;

            xa.fromValue = xa.property.read();

            xa.deletableToBinding = true;

            actions << xa;

        }

    }

    if (d->yString.isValid()) {

        bool ok = false;

        QString script = d->yString.value.script();

        qreal y = script.toFloat(&ok);

        if (ok) {

            QDeclarativeAction ya(d->target, QLatin1String("y"), y);

            actions << ya;

        } else {

            QDeclarativeBinding *newBinding = new QDeclarativeBinding(script, d->target, qmlContext(this));

            newBinding->setTarget(QDeclarativeProperty(d->target, QLatin1String("y")));

            QDeclarativeAction ya;

            ya.property = newBinding->property();

            ya.toBinding = newBinding;

            ya.fromValue = ya.property.read();

            ya.deletableToBinding = true;

            actions << ya;

        }

    }

    if (d->scaleString.isValid()) {

        bool ok = false;

        QString script = d->scaleString.value.script();

        qreal scale = script.toFloat(&ok);

        if (ok) {

            QDeclarativeAction sa(d->target, QLatin1String("scale"), scale);

            actions << sa;

        } else {

            QDeclarativeBinding *newBinding = new QDeclarativeBinding(script, d->target, qmlContext(this));

            newBinding->setTarget(QDeclarativeProperty(d->target, QLatin1String("scale")));

            QDeclarativeAction sa;

            sa.property = newBinding->property();

            sa.toBinding = newBinding;

            sa.fromValue = sa.property.read();

            sa.deletableToBinding = true;

            actions << sa;

        }

    }

    if (d->rotationString.isValid()) {

        bool ok = false;

        QString script = d->rotationString.value.script();

        qreal rotation = script.toFloat(&ok);

        if (ok) {

            QDeclarativeAction ra(d->target, QLatin1String("rotation"), rotation);

            actions << ra;

        } else {

            QDeclarativeBinding *newBinding = new QDeclarativeBinding(script, d->target, qmlContext(this));

            newBinding->setTarget(QDeclarativeProperty(d->target, QLatin1String("rotation")));

            QDeclarativeAction ra;

            ra.property = newBinding->property();

            ra.toBinding = newBinding;

            ra.fromValue = ra.property.read();

            ra.deletableToBinding = true;

            actions << ra;

        }

    }

    if (d->widthString.isValid()) {

        bool ok = false;

        QString script = d->widthString.value.script();

        qreal width = script.toFloat(&ok);

        if (ok) {

            QDeclarativeAction wa(d->target, QLatin1String("width"), width);

            actions << wa;

        } else {

            QDeclarativeBinding *newBinding = new QDeclarativeBinding(script, d->target, qmlContext(this));

            newBinding->setTarget(QDeclarativeProperty(d->target, QLatin1String("width")));

            QDeclarativeAction wa;

            wa.property = newBinding->property();

            wa.toBinding = newBinding;

            wa.fromValue = wa.property.read();

            wa.deletableToBinding = true;

            actions << wa;

        }

    }

    if (d->heightString.isValid()) {

        bool ok = false;

        QString script = d->heightString.value.script();

        qreal height = script.toFloat(&ok);

        if (ok) {

            QDeclarativeAction ha(d->target, QLatin1String("height"), height);

            actions << ha;

        } else {

            QDeclarativeBinding *newBinding = new QDeclarativeBinding(script, d->target, qmlContext(this));

            newBinding->setTarget(QDeclarativeProperty(d->target, QLatin1String("height")));

            QDeclarativeAction ha;

            ha.property = newBinding->property();

            ha.toBinding = newBinding;

            ha.fromValue = ha.property.read();

            ha.deletableToBinding = true;

            actions << ha;

        }

    }

    return actions;

}

class AccessibleFxItem : public QDeclarativeItem

{

    Q_OBJECT

    Q_DECLARE_PRIVATE_D(QGraphicsItem::d_ptr.data(), QDeclarativeItem)

public:

    int siblingIndex() {

        Q_D(QDeclarativeItem);

        return d->siblingIndex;

    }

};

void QDeclarativeParentChange::saveOriginals()

{

    Q_D(QDeclarativeParentChange);

    saveCurrentValues();

    d->origParent = d->rewindParent;

    d->origStackBefore = d->rewindStackBefore;

}

/*void QDeclarativeParentChange::copyOriginals(QDeclarativeActionEvent *other)

{

    Q_D(QDeclarativeParentChange);

    QDeclarativeParentChange *pc = static_cast<QDeclarativeParentChange*>(other);

    d->origParent = pc->d_func()->rewindParent;

    d->origStackBefore = pc->d_func()->rewindStackBefore;

    saveCurrentValues();

}*/

void QDeclarativeParentChange::execute(Reason)

{

    Q_D(QDeclarativeParentChange);

    d->doChange(d->parent);

}

bool QDeclarativeParentChange::isReversable()

{

    return true;

}

void QDeclarativeParentChange::reverse(Reason)

{

    Q_D(QDeclarativeParentChange);