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#include "qtimeline.h"

#include <private/qobject_p.h>

#include <QtCore/qdatetime.h>

#include <QtCore/qcoreevent.h>

#include <QtCore/qmath.h>

QT_BEGIN_NAMESPACE

class QTimeLinePrivate : public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QTimeLine)

public:

    inline QTimeLinePrivate()

        : startTime(0), duration(1000), startFrame(0), endFrame(0),

          updateInterval(1000 / 25),

          totalLoopCount(1), currentLoopCount(0), currentTime(0), timerId(0),

          direction(QTimeLine::Forward), easingCurve(QEasingCurve::InOutSine),

          state(QTimeLine::NotRunning)

    { }

    int startTime;

    int duration;

    int startFrame;

    int endFrame;

    int updateInterval;

    int totalLoopCount;

    int currentLoopCount;

    int currentTime;

    int timerId;

    QTime timer;

    QTimeLine::Direction direction;

    QEasingCurve easingCurve;

    QTimeLine::State state;

    inline void setState(QTimeLine::State newState)

    {

        Q_Q(QTimeLine);

        if (newState != state)

            emit q->stateChanged(state = newState);

    }

    void setCurrentTime(int msecs);

};

/*!

    \internal

*/

void QTimeLinePrivate::setCurrentTime(int msecs)

{

    Q_Q(QTimeLine);

    qreal lastValue = q->currentValue();

    int lastFrame = q->currentFrame();

    // Determine if we are looping.

    int elapsed = (direction == QTimeLine::Backward) ? (-msecs +  duration) : msecs;

    int loopCount = elapsed / duration;

    bool looping = (loopCount != currentLoopCount);

#ifdef QTIMELINE_DEBUG

    qDebug() << "QTimeLinePrivate::setCurrentTime:" << msecs << duration << "with loopCount" << loopCount

             << "currentLoopCount" << currentLoopCount

             << "looping" << looping;

#endif

    if (looping)

        currentLoopCount = loopCount;

    // Normalize msecs to be between 0 and duration, inclusive.

    currentTime = elapsed % duration;

    if (direction == QTimeLine::Backward)

        currentTime = duration - currentTime;

    // Check if we have reached the end of loopcount.

    bool finished = false;

    if (totalLoopCount && currentLoopCount >= totalLoopCount) {

        finished = true;

        currentTime = (direction == QTimeLine::Backward) ? 0 : duration;

        currentLoopCount = totalLoopCount - 1;

    }

    int currentFrame = q->frameForTime(currentTime);

#ifdef QTIMELINE_DEBUG

    qDebug() << "QTimeLinePrivate::setCurrentTime: frameForTime" << currentTime << currentFrame;

#endif

    if (lastValue != q->currentValue())

        emit q->valueChanged(q->currentValue());

    if (lastFrame != currentFrame) {

        const int transitionframe = (direction == QTimeLine::Forward ? endFrame : startFrame);

        if (looping && !finished && transitionframe != currentFrame) {

#ifdef QTIMELINE_DEBUG

            qDebug() << "QTimeLinePrivate::setCurrentTime: transitionframe";

#endif

            emit q->frameChanged(transitionframe);

        }

#ifdef QTIMELINE_DEBUG

        else {

            QByteArray reason;

            if (!looping)

                reason += " not looping";

            if (finished) {

                if (!reason.isEmpty())

                    reason += " and";

                reason += " finished";

            }

            if (transitionframe == currentFrame) {

                if (!reason.isEmpty())

                    reason += " and";

                reason += " transitionframe is equal to currentFrame: " + QByteArray::number(currentFrame);

            }

            qDebug("QTimeLinePrivate::setCurrentTime: not transitionframe because %s",  reason.constData());

        }

#endif

        emit q->frameChanged(currentFrame);

    }

    if (finished && state == QTimeLine::Running) {

        q->stop();

        emit q->finished();

    }

}

/*!

    \class QTimeLine

    \brief The QTimeLine class provides a timeline for controlling animations.

    \since 4.2

    \ingroup animation

    It's most commonly used to animate a GUI control by calling a slot

    periodically. You can construct a timeline by passing its duration in

    milliseconds to QTimeLine's constructor. The timeline's duration describes

    for how long the animation will run. Then you set a suitable frame range

    by calling setFrameRange(). Finally connect the frameChanged() signal to a

    suitable slot in the widget you wish to animate (e.g., setValue() in

    QProgressBar). When you proceed to calling start(), QTimeLine will enter

    Running state, and start emitting frameChanged() at regular intervals,

    causing your widget's connected property's value to grow from the lower

    end to the upper and of your frame range, at a steady rate. You can

    specify the update interval by calling setUpdateInterval(). When done,

    QTimeLine enters NotRunning state, and emits finished().

    Example:

    \snippet doc/src/snippets/code/src_corelib_tools_qtimeline.cpp 0

    You can also use QTimeLine with the

    \l{Graphics View}{Graphics View framework} for

    animations. The QGraphicsItemAnimation class implements animation

    of \l{QGraphicsItem}{QGraphicsItems} with a timeline.

    By default the timeline runs once, from the beginning and towards the end,

    upon which you must call start() again to restart from the beginning. To

    make the timeline loop, you can call setLoopCount(), passing the number of

    times the timeline should run before finishing. The direction can also be

    changed, causing the timeline to run backward, by calling

    setDirection(). You can also pause and unpause the timeline while it's

    running by calling setPaused(). For interactive control, the

    setCurrentTime() function is provided, which sets the time position of the

    time line directly. Although most useful in NotRunning state, (e.g.,

    connected to a valueChanged() signal in a QSlider,) this function can be

    called at any time.

    The frame interface is useful for standard widgets, but QTimeLine can be

    used to control any type of animation. The heart of QTimeLine lies in the

    valueForTime() function, which generates a \e value between 0 and 1 for a

    given time. This value is typically used to describe the steps of an

    animation, where 0 is the first step of an animation, and 1 is the last

    step. When running, QTimeLine generates values between 0 and 1 by calling

    valueForTime() and emitting valueChanged(). By default, valueForTime()

    applies an interpolation algorithm to generate these value. You can choose

    from a set of predefined timeline algorithms by calling

    setCurveShape().

    Note that by default, QTimeLine uses the EaseInOut curve shape,

    which provides a value that grows slowly, then grows steadily, and

    finally grows slowly. For a custom timeline, you can reimplement

    valueForTime(), in which case QTimeLine's curveShape property is ignored.

    \sa QProgressBar, QProgressDialog, QGraphicsItemAnimation

*/

/*!

    \enum QTimeLine::State

    This enum describes the state of the timeline.

    \value NotRunning The timeline is not running. This is the initial state

    of QTimeLine, and the state QTimeLine reenters when finished. The current

    time, frame and value remain unchanged until either setCurrentTime() is

    called, or the timeline is started by calling start().

    \value Paused The timeline is paused (i.e., temporarily

    suspended). Calling setPaused(false) will resume timeline activity.

    \value Running The timeline is running. While control is in the event

    loop, QTimeLine will update its current time at regular intervals,

    emitting valueChanged() and frameChanged() when appropriate.

    \sa state(), stateChanged()

*/

/*!

    \enum QTimeLine::Direction

    This enum describes the direction of the timeline when in \l Running state.

    \value Forward The current time of the timeline increases with time (i.e.,

    moves from 0 and towards the end / duration).

    \value Backward The current time of the timeline decreases with time (i.e.,

    moves from the end / duration and towards 0).

    \sa setDirection()

*/

/*!

    \enum QTimeLine::CurveShape

    This enum describes the default shape of QTimeLine's value curve. The

    default, shape is EaseInOutCurve. The curve defines the relation

    between the value and the timeline.

    \value EaseInCurve The value starts growing slowly, then increases in speed.

    \value EaseOutCurve The value starts growing steadily, then ends slowly.

    \value EaseInOutCurve The value starts growing slowly, then runs steadily, then grows slowly again.

    \value LinearCurve The value grows linearly (e.g., if the duration is 1000 ms,

           the value at time 500 ms is 0.5).

    \value SineCurve The value grows sinusoidally.

    \value CosineCurve The value grows cosinusoidally.

    \sa setCurveShape()

*/

/*!

    \fn QTimeLine::valueChanged(qreal value)

    QTimeLine emits this signal at regular intervals when in \l Running state,

    but only if the current value changes. \a value is the current value. \a value is

    a number between 0.0 and 1.0

    \sa QTimeLine::setDuration(), QTimeLine::valueForTime(), QTimeLine::updateInterval

*/

/*!

    \fn QTimeLine::frameChanged(int frame)

    QTimeLine emits this signal at regular intervals when in \l Running state,

    but only if the current frame changes. \a frame is the current frame number.

    \sa QTimeLine::setFrameRange(), QTimeLine::updateInterval

*/

/*!

    \fn QTimeLine::stateChanged(QTimeLine::State newState)

    This signal is emitted whenever QTimeLine's state changes. The new state

    is \a newState.

*/

/*!

    \fn QTimeLine::finished()

    This signal is emitted when QTimeLine finishes (i.e., reaches the end of

    its time line), and does not loop.

*/

/*!

    Constructs a timeline with a duration of \a duration milliseconds. \a

    parent is passed to QObject's constructor. The default duration is 1000

    milliseconds.

 */

QTimeLine::QTimeLine(int duration, QObject *parent)

    : QObject(*new QTimeLinePrivate, parent)

{

    setDuration(duration);

}

/*!

    Destroys the timeline.

 */

QTimeLine::~QTimeLine()

{

    Q_D(QTimeLine);

    if (d->state == Running)

        stop();

}

/*!

    Returns the state of the timeline.

    \sa start(), setPaused(), stop()

*/

QTimeLine::State QTimeLine::state() const

{

    Q_D(const QTimeLine);

    return d->state;

}

/*!

    \property QTimeLine::loopCount

    \brief the number of times the timeline should loop before it's finished.

    A loop count of of 0 means that the timeline will loop forever.

    By default, this property contains a value of 1.

*/

int QTimeLine::loopCount() const

{

    Q_D(const QTimeLine);

    return d->totalLoopCount;

}

void QTimeLine::setLoopCount(int count)

{

    Q_D(QTimeLine);

    d->totalLoopCount = count;

}

/*!

    \property QTimeLine::direction

    \brief the direction of the timeline when QTimeLine is in \l Running

    state.

    This direction indicates whether the time moves from 0 towards the

    timeline duration, or from the value of the duration and towards 0 after

    start() has been called.

    By default, this property is set to \l Forward.

*/

QTimeLine::Direction QTimeLine::direction() const

{

    Q_D(const QTimeLine);

    return d->direction;

}

void QTimeLine::setDirection(Direction direction)

{

    Q_D(QTimeLine);

    d->direction = direction;

    d->startTime = d->currentTime;

    d->timer.start();

}

/*!

    \property QTimeLine::duration

    \brief the total duration of the timeline in milliseconds.

    By default, this value is 1000 (i.e., 1 second), but you can change this

    by either passing a duration to QTimeLine's constructor, or by calling

    setDuration(). The duration must be larger than 0.

    \note Changing the duration does not cause the current time to be reset

    to zero or the new duration. You also need to call setCurrentTime() with

    the desired value.

*/

int QTimeLine::duration() const

{

    Q_D(const QTimeLine);

    return d->duration;

}

void QTimeLine::setDuration(int duration)

{

    Q_D(QTimeLine);

    if (duration <= 0) {

        qWarning("QTimeLine::setDuration: cannot set duration <= 0");

        return;

    }

    d->duration = duration;

}

/*!

    Returns the start frame, which is the frame corresponding to the start of

    the timeline (i.e., the frame for which the current value is 0).

    \sa setStartFrame(), setFrameRange()

*/

int QTimeLine::startFrame() const

{

    Q_D(const QTimeLine);

    return d->startFrame;

}

/*!

    Sets the start frame, which is the frame corresponding to the start of the

    timeline (i.e., the frame for which the current value is 0), to \a frame.

    \sa startFrame(), endFrame(), setFrameRange()

*/

void QTimeLine::setStartFrame(int frame)

{

    Q_D(QTimeLine);

    d->startFrame = frame;

}

/*!

    Returns the end frame, which is the frame corresponding to the end of the

    timeline (i.e., the frame for which the current value is 1).

    \sa setEndFrame(), setFrameRange()

*/

int QTimeLine::endFrame() const

{

    Q_D(const QTimeLine);

    return d->endFrame;

}

/*!

    Sets the end frame, which is the frame corresponding to the end of the

    timeline (i.e., the frame for which the current value is 1), to \a frame.

    \sa endFrame(), startFrame(), setFrameRange()

*/

void QTimeLine::setEndFrame(int frame)

{

    Q_D(QTimeLine);

    d->endFrame = frame;

}

/*!

    Sets the timeline's frame counter to start at \a startFrame, and end and

    \a endFrame. For each time value, QTimeLine will find the corresponding

    frame when you call currentFrame() or frameForTime() by interpolating,

    using the return value of valueForTime().

    When in Running state, QTimeLine also emits the frameChanged() signal when

    the frame changes.

    \sa startFrame(), endFrame(), start(), currentFrame()

*/

void QTimeLine::setFrameRange(int startFrame, int endFrame)

{

    Q_D(QTimeLine);

    d->startFrame = startFrame;

    d->endFrame = endFrame;

}

/*!

    \property QTimeLine::updateInterval

    \brief the time in milliseconds between each time QTimeLine updates its

    current time.

    When updating the current time, QTimeLine will emit valueChanged() if the

    current value changed, and frameChanged() if the frame changed.

    By default, the interval is 40 ms, which corresponds to a rate of 25

    updates per second.

*/

int QTimeLine::updateInterval() const

{

    Q_D(const QTimeLine);

    return d->updateInterval;

}

void QTimeLine::setUpdateInterval(int interval)

{

    Q_D(QTimeLine);

    d->updateInterval = interval;

}

/*!

    \property QTimeLine::curveShape

    \brief the shape of the timeline curve.

    The curve shape describes the relation between the time and value for the

    base implementation of valueForTime().

    If you have reimplemented valueForTime(), this value is ignored.

    By default, this property is set to \l EaseInOutCurve.

    \sa valueForTime()

*/

QTimeLine::CurveShape QTimeLine::curveShape() const

{

    Q_D(const QTimeLine);

    switch (d->easingCurve.type()) {

    default:

    case QEasingCurve::InOutSine:

        return EaseInOutCurve;

    case QEasingCurve::InCurve:

        return EaseInCurve;

    case QEasingCurve::OutCurve:

        return EaseOutCurve;

    case QEasingCurve::Linear:

        return LinearCurve;

    case QEasingCurve::SineCurve:

        return SineCurve;

    case QEasingCurve::CosineCurve:

        return CosineCurve;