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#include "private/qdeclarativestate_p.h"

#include "private/qdeclarativestategroup_p.h"

#include "private/qdeclarativestate_p_p.h"

#include "private/qdeclarativestateoperations_p.h"

#include "private/qdeclarativeanimation_p.h"

#include "private/qdeclarativeanimation_p_p.h"

#include "private/qdeclarativetransitionmanager_p_p.h"

#include <QParallelAnimationGroup>

QT_BEGIN_NAMESPACE

/*!

    \qmlclass Transition QDeclarativeTransition

    \since 4.7

    \brief The Transition element defines animated transitions that occur on state changes.

    A Transition defines the animations to be applied when a \l State change occurs.

    For example, the following \l Rectangle has two states: the default state, and

    an added "moved" state. In the "moved state, the rectangle's position changes 

    changes between the default and the "moved" state, any changes

    to the \c x and \c y properties should be animated, using an \c Easing.InOutQuad.

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

    \qml

    Item {

        ...

        transitions: [

            Transition { ... }

        ]

    }

    \endqml

*/

//ParallelAnimationWrapper allows us to do a "callback" when the animation finishes, rather than connecting

//and disconnecting signals and slots frequently

class ParallelAnimationWrapper : public QParallelAnimationGroup

{

    Q_OBJECT

public:

    ParallelAnimationWrapper(QObject *parent = 0) : QParallelAnimationGroup(parent) {}

    QDeclarativeTransitionPrivate *trans;

protected:

    virtual void updateState(QAbstractAnimation::State newState, QAbstractAnimation::State oldState);

};

class QDeclarativeTransitionPrivate : public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QDeclarativeTransition)

public:

    QDeclarativeTransitionPrivate() 

    : fromState(QLatin1String("*")), toState(QLatin1String("*")), 

      reversed(false), reversible(false), endState(0)

    {

        group.trans = this;

    }

    QString fromState;

    QString toState;

    bool reversed;

    bool reversible;

    ParallelAnimationWrapper group;

    QDeclarativeTransitionManager *endState;

    void complete()

    {

        endState->complete();

    }

    static void append_animation(QDeclarativeListProperty<QDeclarativeAbstractAnimation> *list, QDeclarativeAbstractAnimation *a);

    QList<QDeclarativeAbstractAnimation *> animations;

};

void QDeclarativeTransitionPrivate::append_animation(QDeclarativeListProperty<QDeclarativeAbstractAnimation> *list, QDeclarativeAbstractAnimation *a)

{

    QDeclarativeTransition *q = static_cast<QDeclarativeTransition *>(list->object);

    q->d_func()->animations.append(a);

    q->d_func()->group.addAnimation(a->qtAnimation());

    a->setDisableUserControl();

}

void ParallelAnimationWrapper::updateState(QAbstractAnimation::State newState, QAbstractAnimation::State oldState)

{

    QParallelAnimationGroup::updateState(newState, oldState);

    if (newState == Stopped && (duration() == -1

        || (direction() == QAbstractAnimation::Forward && currentLoopTime() == duration())

        || (direction() == QAbstractAnimation::Backward && currentLoopTime() == 0)))

    {

        trans->complete();

    }

}

QDeclarativeTransition::QDeclarativeTransition(QObject *parent)

    : QObject(*(new QDeclarativeTransitionPrivate), parent)

{

}

QDeclarativeTransition::~QDeclarativeTransition()

{

}

void QDeclarativeTransition::stop()

{

    Q_D(QDeclarativeTransition);

    d->group.stop();

}

void QDeclarativeTransition::setReversed(bool r)

{

    Q_D(QDeclarativeTransition);

    d->reversed = r;

}

void QDeclarativeTransition::prepare(QDeclarativeStateOperation::ActionList &actions,

                            QList<QDeclarativeProperty> &after,

                            QDeclarativeTransitionManager *endState)

{

    Q_D(QDeclarativeTransition);

    qmlExecuteDeferred(this);

    if (d->reversed) {

        for (int ii = d->animations.count() - 1; ii >= 0; --ii) {

            d->animations.at(ii)->transition(actions, after, QDeclarativeAbstractAnimation::Backward);

        }

    } else {

        for (int ii = 0; ii < d->animations.count(); ++ii) {

            d->animations.at(ii)->transition(actions, after, QDeclarativeAbstractAnimation::Forward);

        }

    }

    d->endState = endState;

    d->group.setDirection(d->reversed ? QAbstractAnimation::Backward : QAbstractAnimation::Forward);

    d->group.start();

}

/*!

    \qmlproperty string Transition::from

    \qmlproperty string Transition::to

    These properties indicate the state changes that trigger the transition.

    The default values for these properties is "*" (that is, any state).

    For example, the following transition has not set the \c to and \c from

    properties, so the animation is always applied when changing between

    the two states (i.e. when the mouse is pressed and released).

    \snippet doc/src/snippets/declarative/transition-from-to.qml 0

    If the transition was changed to this:

    \qml

        transitions: Transition { 

            to: "brighter"

            ColorAnimation { duration: 1000 }

        }

    }

    \endqml

    The animation would only be applied when changing from the default state to

    the "brighter" state (i.e. when the mouse is pressed, but not on release).

    \sa reversible

*/

QString QDeclarativeTransition::fromState() const

{

    Q_D(const QDeclarativeTransition);

    return d->fromState;

}

void QDeclarativeTransition::setFromState(const QString &f)

{

    Q_D(QDeclarativeTransition);

    if (f == d->fromState)

        return;

    d->fromState = f;

    emit fromChanged();

}

/*!

    \qmlproperty bool Transition::reversible

    This property holds whether the transition should be automatically reversed when the conditions that triggered this transition are reversed.

    The default value is false.

    By default, transitions run in parallel and are applied to all state

    changes if the \l from and \l to states have not been set. In this

    situation, the transition is automatically applied when a state change

    is reversed, and it is not necessary to set this property to reverse

    the transition.

    However, if a SequentialAnimation is used, or if the \l from or \l to 

    properties have been set, this property will need to be set to reverse

    a transition when a state change is reverted. For example, the following

    transition applies a sequential animation when the mouse is pressed,

    and reverses the sequence of the animation when the mouse is released:

    \snippet doc/src/snippets/declarative/transition-reversible.qml 0

    If the transition did not set the \c to and \c reversible values, then 

    on the mouse release, the transition would play the PropertyAnimation

    before the ColorAnimation instead of reversing the sequence.

*/

bool QDeclarativeTransition::reversible() const

{

    Q_D(const QDeclarativeTransition);

    return d->reversible;

}

void QDeclarativeTransition::setReversible(bool r)

{

    Q_D(QDeclarativeTransition);

    if (r == d->reversible)

        return;

    d->reversible = r;

    emit reversibleChanged();

}

QString QDeclarativeTransition::toState() const

{

    Q_D(const QDeclarativeTransition);

    return d->toState;

}

void QDeclarativeTransition::setToState(const QString &t)

{

    Q_D(QDeclarativeTransition);

    if (t == d->toState)

        return;

    d->toState = t;

    emit toChanged();

}

/*!

    \qmlproperty list<Animation> Transition::animations

    \default

    This property holds a list of the animations to be run for this transition.

    \qml

    Transition {

        PropertyAnimation { ... }

        NumberAnimation { ... }

    }

    \endqml

    The top-level animations are run in parallel. To run them sequentially,

    define them within a SequentialAnimation:

    \qml

    Transition {

        SequentialAnimation {

            PropertyAnimation { ... }

            NumberAnimation { ... }

        }

    }

    \endqml

*/

QDeclarativeListProperty<QDeclarativeAbstractAnimation> QDeclarativeTransition::animations()

{

    Q_D(QDeclarativeTransition);

    return QDeclarativeListProperty<QDeclarativeAbstractAnimation>(this, &d->animations, QDeclarativeTransitionPrivate::append_animation);

}

QT_END_NAMESPACE

#include <qdeclarativetransition.moc>