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#include "q3dssceneelement_p.h"
#include <private/q3dspresentation_p.h>

QT_BEGIN_NAMESPACE

/*!
    \class Q3DSSceneElement
    \inherits Q3DSElement
    \inmodule Qt3DStudioRuntime2
    \since Qt 3D Studio 2.0

    \brief Controls the special Scene or Component scene objects in a Qt 3D
    Studio presentation.

    This class is a convenience class for controlling the properties of Scene
    and Component objects in the scene. These are special since they have a
    time context, meaning they control a timline and a set of associated
    slides.

    \note The functionality of Q3DSSceneElement is equivalent to
    Q3DSPresentation::goToTime() and Q3DSPresentation::goToSlide().

    \sa Q3DSPresentation, Q3DSWidget, Q3DSSurfaceViewer, Q3DSElement
 */

/*!
    \internal
 */
Q3DSSceneElement::Q3DSSceneElement(QObject *parent)
    : Q3DSElement(*new Q3DSSceneElementPrivate, parent)
{
}

/*!
    Constructs a Q3DSSceneElement instance and associated it with the object
    specified by \a elementPath and the given \a presentation. An optional \a
    parent object can be specified.
 */
Q3DSSceneElement::Q3DSSceneElement(Q3DSPresentation *presentation, const QString &elementPath, QObject *parent)
    : Q3DSElement(*new Q3DSSceneElementPrivate, parent)
{
    Q_D(Q3DSSceneElement);
    d->elementPath = elementPath;
    d->presentation = presentation;
}

/*!
    \internal
 */
Q3DSSceneElement::Q3DSSceneElement(Q3DSSceneElementPrivate &dd, QObject *parent)
    : Q3DSElement(dd, parent)
{
}

/*!
   Destructor.
 */
Q3DSSceneElement::~Q3DSSceneElement()
{
}

/*!
    \property Q3DSSceneElement::currentSlideIndex

    Holds the index of the currently active slide of the tracked time context.

    \note If this property is set to something else than the default slide for
    the scene at the initial declaration of SceneElement, a changed signal for
    the default slide may still be emitted before the slide changes to the
    desired one. This happens in order to ensure we end up with the index of
    the slide that is actually shown even if the slide specified in the initial
    declaration is invalid.
*/
int Q3DSSceneElement::currentSlideIndex() const
{
    Q_D(const Q3DSSceneElement);
    return d->currentSlideIndex;
}

/*!
    \property Q3DSSceneElement::previousSlideIndex

    Holds the index of the previously active slide of the tracked time context.

    This property is read-only.
*/
int Q3DSSceneElement::previousSlideIndex() const
{
    Q_D(const Q3DSSceneElement);
    return d->previousSlideIndex;
}

/*!
    \property Q3DSSceneElement::currentSlideName

    Holds the name of the currently active slide of the tracked time context.

    \note If this property is set to something else than the default slide for
    the scene at the initial declaration of SceneElement, a changed signal for
    the default slide may still be emitted before the slide changes to the
    desired one. This happens in order to ensure we end up with the index of
    the slide that is actually shown even if the slide specified in the initial
    declaration is invalid.
*/
QString Q3DSSceneElement::currentSlideName() const
{
    Q_D(const Q3DSSceneElement);
    return d->currentSlideName;
}

/*!
    \property Q3DSSceneElement::previousSlideName

    Holds the name of the previously active slide of the tracked time context.

    This property is read-only.
*/
QString Q3DSSceneElement::previousSlideName() const
{
    Q_D(const Q3DSSceneElement);
    return d->previousSlideName;
}

void Q3DSSceneElement::setCurrentSlideIndex(int currentSlideIndex)
{
    Q_D(Q3DSSceneElement);
    // This is also exposed as a property so we may need to defer applying the
    // value transparently to the user code. (relevant with QML + Studio3D)
    if (d->presentation && !d->elementPath.isEmpty())
        d->presentation->goToSlide(d->elementPath, currentSlideIndex);
    else
        d->pendingSlideSetIndex = currentSlideIndex; // defer to sendPendingValues()
}

void Q3DSSceneElement::setCurrentSlideName(const QString &currentSlideName)
{
    Q_D(Q3DSSceneElement);
    if (d->presentation && !d->elementPath.isEmpty())
        d->presentation->goToSlide(d->elementPath, currentSlideName);
    else
        d->pendingSlideSetName = currentSlideName; // defer to sendPendingValues()
}

/*!
    Requests a time context (a Scene or a Component object) to change to the
    next or previous slide, depending on the value of \a next. If the context
    is already at the last or first slide, \a wrap defines if wrapping over to
    the first or last slide, respectively, occurs.
 */
void Q3DSSceneElement::goToSlide(bool next, bool wrap)
{
    Q_D(Q3DSSceneElement);
    if (d->presentation && !d->elementPath.isEmpty())
        d->presentation->goToSlide(d->elementPath, next, wrap);
}

/*!
    Moves the timeline for a time context (a Scene or a Component element) to a
    specific position. The position is given in seconds in \a timeSeconds.
 */
void Q3DSSceneElement::goToTime(float timeSeconds)
{
    Q_D(Q3DSSceneElement);
    if (d->presentation && !d->elementPath.isEmpty())
        d->presentation->goToTime(d->elementPath, timeSeconds);
}

void Q3DSSceneElementPrivate::sendPendingValues()
{
    if (!presentation || elementPath.isEmpty())
        return;

    if (pendingSlideSetIndex >= 0) {
        presentation->goToSlide(elementPath, pendingSlideSetIndex);
        pendingSlideSetIndex = -1;
    }
    if (!pendingSlideSetName.isEmpty()) {
        presentation->goToSlide(elementPath, pendingSlideSetName);
        pendingSlideSetName.clear();
    }
}

void Q3DSSceneElementPrivate::_q_onSlideEntered(const QString &contextElemPath, int index, const QString &name)
{
    Q_Q(Q3DSSceneElement);
    Q_ASSERT(presentation);

    // only care about slide changes for the scene or component our elementPath specifies
    if (!Q3DSPresentationPrivate::get(presentation)->compareElementPath(contextElemPath, elementPath))
        return;

    const bool notifyCurrent = currentSlideIndex != index;
    const bool notifyPrevious = previousSlideIndex != currentSlideIndex;

    previousSlideIndex = currentSlideIndex;
    previousSlideName = currentSlideName;

    currentSlideIndex = index;
    currentSlideName = name;

    if (notifyPrevious) {
        emit q->previousSlideIndexChanged(previousSlideIndex);
        emit q->previousSlideNameChanged(previousSlideName);
    }

    if (notifyCurrent) {
        emit q->currentSlideIndexChanged(currentSlideIndex);
        emit q->currentSlideNameChanged(currentSlideName);
    }
}

void Q3DSSceneElementPrivate::setPresentation(Q3DSPresentation *pres)
{
    Q_Q(Q3DSSceneElement);
    presentation = pres;
    QObject::connect(presentation, SIGNAL(slideEntered(QString,int,QString)),
                     q, SLOT(_q_onSlideEntered(QString,int,QString)));
}

/*!
    \qmltype SceneElement
    \instantiates Q3DSSceneElement
    \inherits Element
    \inqmlmodule QtStudio3D
    \ingroup 3dstudioruntime2

    \brief Controls the special Scene or Component scene objects in a Qt 3D
    Studio presentation.

    This type is a convenience for controlling the properties of Scene
    and Component objects in the scene. These are special since they have a
    time context, meaning they control a timline and a set of associated
    slides.

    \sa Studio3D, Presentation, Element
*/

/*!
    \qmlproperty int SceneElement::currentSlideIndex

    Holds the index of the currently active slide of the tracked time context.

    Changing the current slide via this property is asynchronous. The property
    value will not actually change until the next frame has been processed, and
    even then only if the new slide was valid.

    \note If this property is set to something else than the default slide for
    the scene at the initial declaration of SceneElement, a changed signal for
    the default slide may still be emitted before the slide changes to the
    desired one. This happens in order to ensure we end up with the index of
    the slide that is actually shown even if the slide specified in the initial
    declaration is invalid.
*/

/*!
    \qmlproperty int SceneElement::previousSlideIndex

    Holds the index of the previously active slide of the tracked time context.

    This property is read-only.
*/

/*!
    \qmlproperty string SceneElement::currentSlideName

    Holds the name of the currently active slide of the tracked time context.

    Changing the current slide via this property is asynchronous. The property
    value will not actually change until the next frame has been processed, and
    even then only if the new slide was valid.

    \note If this property is set to something else than the default slide for
    the scene at the initial declaration of SceneElement, a changed signal for
    the default slide may still be emitted before the slide changes to the
    desired one. This happens in order to ensure we end up with the index of
    the slide that is actually shown even if the slide specified in the initial
    declaration is invalid.
*/

/*!
    \qmlproperty string SceneElement::previousSlideName

    Holds the name of the previously active slide of the tracked time context.

    This property is read-only.
*/

/*!
    \qmlsignal SceneElement::currentSlideIndexChanged(int currentSlideIndex)

    This signal is emitted when the current slide changes.
    The new value is provided in the \a currentSlideIndex parameter.

    This signal is always emitted with currentSlideNameChanged.

    The corresponding handler is \c onCurrentSlideIndexChanged.
*/

/*!
    \qmlsignal SceneElement::previousSlideIndexChanged(int previousSlideIndex)

    This signal is emitted when the previous slide changes.
    The new value is provided in the \a previousSlideIndex parameter.

    This signal is always emitted with previousSlideNameChanged.

    The corresponding handler is \c onPreviousSlideIndexChanged.
*/

/*!
    \qmlsignal SceneElement::currentSlideNameChanged(string currentSlideName)

    This signal is emitted when the current slide changes.
    The new value is provided in the \a currentSlideName parameter.

    This signal is always emitted with currentSlideIndexChanged.

    The corresponding handler is \c onCurrentSlideNameChanged.
*/

/*!
    \qmlsignal SceneElement::previousSlideNameChanged(string previousSlideName)

    This signal is emitted when the previous slide changes.
    The new value is provided in the \a previousSlideName parameter.

    This signal is always emitted with previousSlideIndexChanged.

    The corresponding handler is \c onPreviousSlideNameChanged.
*/

/*!
    \qmlmethod void SceneElement::goToSlide(bool next, bool wrap)

    Requests a time context (a Scene or a Component object) to change to the
    next or previous slide, depending on the value of \a next. If the context
    is already at the last or first slide, \a wrap defines if wrapping over to
    the first or last slide, respectively, occurs.
*/

/*!
    \qmlmethod void SceneElement::goToTime(string elementPath, real time)

    Sets a time context (a Scene or a Component element) to a specific playback \a time in seconds.

    For behavior details, see Presentation::goToTime() documentation.
*/

QT_END_NAMESPACE

#include "moc_q3dssceneelement.cpp"