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#include <private/qobject_p.h>
#include "qmlanimation.h"
#include "qmltransition.h"
#include "qmlbehaviour.h"
#include <QtDeclarative/qmlcontext.h>


QT_BEGIN_NAMESPACE
QML_DEFINE_TYPE(QmlBehaviour,Behaviour);


class QmlBehaviourData : public QObject
{
Q_OBJECT
public:
    QmlBehaviourData(QObject *parent)
        : QObject(parent) {}

    Q_PROPERTY(QVariant endValue READ endValue NOTIFY valuesChanged);
    Q_PROPERTY(QVariant startValue READ startValue NOTIFY valuesChanged);
    QVariant endValue() const { return e; }
    QVariant startValue() const { return s; }

    QVariant e;
    QVariant s;

Q_SIGNALS:
    void valuesChanged();

private:
    friend class QmlBehaviour;
};

class QmlBehaviourPrivate : public QObjectPrivate
{
public:
    QmlBehaviourPrivate()
        : context(0), valueData(0), operations(this) {}
    QmlMetaProperty property;
    QVariant currentValue;

    QVariant fromValue;
    QVariant toValue;
    QmlContext *context;
    QmlBehaviourData *valueData;
    class AnimationList : public QmlConcreteList<QmlAbstractAnimation *>
    {
    public:
        AnimationList(QmlBehaviourPrivate *parent) : _parent(parent) {}
        virtual void append(QmlAbstractAnimation *a)
        {
            QmlConcreteList<QmlAbstractAnimation *>::append(a);
            _parent->group->addAnimation(a->qtAnimation());
        }
        virtual void clear() {  QmlConcreteList<QmlAbstractAnimation *>::clear(); } //###
    private:
        QmlBehaviourPrivate *_parent;
    };
    AnimationList operations;
    QSequentialAnimationGroup *group;
};

/*!
    \qmlclass Behaviour QmlBehaviour
    \brief The Behaviour element allows you to specify a default animation for a property change.

    In example below, the rect will use a bounce easing curve over 200 millisecond for any changes to its y property:
    \code
    Rect {
        width: 20; height: 20
        color: "#00ff00"
        y: 200  //initial value
        y: Behaviour {
            NumericAnimation {
                easing: "easeOutBounce(amplitude:100)"
                duration: 200
            }
        }
    }
    \endcode
*/

QmlBehaviour::QmlBehaviour(QObject *parent)
: QmlPropertyValueSource(*(new QmlBehaviourPrivate), parent)
{
    Q_D(QmlBehaviour);
    d->valueData = new QmlBehaviourData(this);
    d->group = new QSequentialAnimationGroup(this);
}

/*!
    \qmlproperty QVariant Behaviour::fromValue
    This property holds a selector specifying a starting value for the behaviour

    If you only want the behaviour to apply when the change starts at a
    specific value you can specify fromValue. This selector is used in conjunction
    with the toValue selector.
*/

QVariant QmlBehaviour::fromValue() const
{
    Q_D(const QmlBehaviour);
    return d->fromValue;
}

void QmlBehaviour::setFromValue(const QVariant &v)
{
    Q_D(QmlBehaviour);
    d->fromValue = v;
}

/*!
    \qmlproperty QVariant Behaviour::toValue
    This property holds a selector specifying a ending value for the behaviour

    If you only want the behaviour to apply when the change ends at a
    specific value you can specify toValue. This selector is used in conjunction
    with the fromValue selector.
*/

QVariant QmlBehaviour::toValue() const
{
    Q_D(const QmlBehaviour);
    return d->toValue;
}

void QmlBehaviour::setToValue(const QVariant &v)
{
    Q_D(QmlBehaviour);
    d->toValue = v;
}

QmlList<QmlAbstractAnimation *>* QmlBehaviour::operations()
{
    Q_D(QmlBehaviour);
    return &d->operations;
}

QmlBehaviour::~QmlBehaviour()
{
    //### do we need any other cleanup here?
}

bool QmlBehaviour::_ignore = false;
void QmlBehaviour::propertyValueChanged()
{
    Q_D(QmlBehaviour);
    if (_ignore)
        return;

    QVariant newValue = d->property.read();

    if ((!fromValue().isValid() || fromValue() == d->currentValue) && 
       (!toValue().isValid() || toValue() == newValue)) {

        //### does this clean up everything needed?
        d->group->stop();

        d->valueData->e = newValue;
        d->valueData->s = d->currentValue;
        emit d->valueData->valuesChanged();

        QmlStateOperation::ActionList actions;
        Action action;
        action.property = d->property;
        action.fromValue = d->currentValue;
        action.toValue = newValue;
        actions << action;

        _ignore = true;
        d->property.write(d->currentValue);

        QList<QmlMetaProperty> after;
        for (int ii = 0; ii < d->operations.count(); ++ii) {
            d->operations.at(ii)->transition(actions, after, QmlAbstractAnimation::Forward);
        }
        d->group->start();
        if (!after.contains(d->property))
            d->property.write(newValue);
        _ignore = false;
    }

    d->currentValue = newValue;
}

void QmlBehaviour::setTarget(const QmlMetaProperty &property)
{
    Q_D(QmlBehaviour);
    d->property = property;
    d->currentValue = property.read();
    d->property.connectNotifier(this, SLOT(propertyValueChanged()));
}

void QmlBehaviour::classBegin()
{
    Q_D(QmlBehaviour);
    if (!d->context) {
        d->context = new QmlContext(qmlContext(this), this);
        d->context->addDefaultObject(d->valueData);
    }
    d->context->activate();
}

void QmlBehaviour::classComplete()
{
    Q_D(QmlBehaviour);
    d->context->deactivate();
}

#include "qmlbehaviour.moc"

QT_END_NAMESPACE