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****************************************************************************/

#include "qstandardgestures_p.h"

#include "qgesture.h"

#include "qgesture_p.h"

#include "qevent.h"

#include "qwidget.h"

QT_BEGIN_NAMESPACE

QPanGestureRecognizer::QPanGestureRecognizer()

{

}

QGesture *QPanGestureRecognizer::createGesture(QObject *target)

{

    if (target && target->isWidgetType()) {

        static_cast<QWidget *>(target)->setAttribute(Qt::WA_AcceptTouchEvents);

    }

    return new QPanGesture;

}

QGestureRecognizer::Result QPanGestureRecognizer::filterEvent(QGesture *state, QObject *, QEvent *event)

{

    QPanGesture *q = static_cast<QPanGesture*>(state);

    QPanGesturePrivate *d = q->d_func();

    const QTouchEvent *ev = static_cast<const QTouchEvent*>(event);

    QGestureRecognizer::Result result;

    switch (event->type()) {

    case QEvent::TouchBegin: {

        result = QGestureRecognizer::MaybeGesture;

        QTouchEvent::TouchPoint p = ev->touchPoints().at(0);

        d->lastPosition = p.pos().toPoint();

        d->lastOffset = d->totalOffset = d->offset = QPointF();

        break;

    }

    case QEvent::TouchEnd: {

        if (q->state() != Qt::NoGesture) {

            if (ev->touchPoints().size() == 2) {

                QTouchEvent::TouchPoint p1 = ev->touchPoints().at(0);

                QTouchEvent::TouchPoint p2 = ev->touchPoints().at(1);

                d->lastOffset = d->offset;

                d->offset =

                        QPointF(p1.pos().x() - p1.lastPos().x() + p2.pos().x() - p2.lastPos().x(),

                              p1.pos().y() - p1.lastPos().y() + p2.pos().y() - p2.lastPos().y()) / 2;

                d->totalOffset += d->offset;

            }

            result = QGestureRecognizer::GestureFinished;

        } else {

            result = QGestureRecognizer::NotGesture;

        }

        break;

    }

    case QEvent::TouchUpdate: {

        if (ev->touchPoints().size() >= 2) {

            QTouchEvent::TouchPoint p1 = ev->touchPoints().at(0);

            QTouchEvent::TouchPoint p2 = ev->touchPoints().at(1);

            d->lastOffset = d->offset;

            d->offset =

                    QPointF(p1.pos().x() - p1.lastPos().x() + p2.pos().x() - p2.lastPos().x(),

                          p1.pos().y() - p1.lastPos().y() + p2.pos().y() - p2.lastPos().y()) / 2;

            d->totalOffset += d->offset;

            if (d->totalOffset.x() > 10  || d->totalOffset.y() > 10 ||

                d->totalOffset.x() < -10 || d->totalOffset.y() < -10) {

                result = QGestureRecognizer::GestureTriggered;

            } else {

                result = QGestureRecognizer::MaybeGesture;

            }

        }

        break;

    }

    case QEvent::MouseButtonPress:

    case QEvent::MouseMove:

    case QEvent::MouseButtonRelease:

        result = QGestureRecognizer::Ignore;

        break;

    default:

        result = QGestureRecognizer::Ignore;

        break;

    }

    return result;

}

void QPanGestureRecognizer::reset(QGesture *state)

{

    QPanGesture *pan = static_cast<QPanGesture*>(state);

    QPanGesturePrivate *d = pan->d_func();

    d->totalOffset = d->lastOffset = d->offset = QPointF();

    d->lastPosition = QPoint();

    d->acceleration = 0;

//#if defined(QT_MAC_USE_COCOA)

//    d->singleTouchPanTimer.stop();

//    d->prevMousePos = QPointF(0, 0);

//#endif

    QGestureRecognizer::reset(state);

}

/*! \internal */

/*

bool QPanGestureRecognizer::event(QEvent *event)

{

#if defined(QT_MAC_USE_COCOA)

    Q_D(QPanGesture);

    if (event->type() == QEvent::Timer) {

        const QTimerEvent *te = static_cast<QTimerEvent *>(event);

        if (te->timerId() == d->singleTouchPanTimer.timerId()) {

            d->singleTouchPanTimer.stop();

            updateState(Qt::GestureStarted);

        }

    }

#endif

    bool consume = false;

#if defined(Q_WS_WIN)

#elif defined(QT_MAC_USE_COCOA)

    // The following implements single touch

    // panning on Mac:

    const int panBeginDelay = 300;

    const int panBeginRadius = 3;

    const QTouchEvent *ev = static_cast<const QTouchEvent*>(event);

    switch (event->type()) {

    case QEvent::TouchBegin: {

        if (ev->touchPoints().size() == 1) {

            d->delayManager->setEnabled(true);

            consume = d->delayManager->append(d->gestureTarget, *event);

            d->lastPosition = QCursor::pos();

            d->singleTouchPanTimer.start(panBeginDelay, this);

        }

        break;}

    case QEvent::TouchEnd: {

        d->delayManager->setEnabled(false);

        if (state() != Qt::NoGesture) {

            updateState(Qt::GestureFinished);

            consume = true;

            d->delayManager->clear();

        } else {

            d->delayManager->replay();

        }

        reset();

        break;}

    case QEvent::TouchUpdate: {

        consume = d->delayManager->append(d->gestureTarget, *event);

        if (ev->touchPoints().size() == 1) {

            if (state() == Qt::NoGesture) {

                // INVARIANT: The singleTouchTimer has still not fired.

                // Lets check if the user moved his finger so much from

                // the starting point that it makes sense to cancel:

                const QPointF startPos = ev->touchPoints().at(0).startPos().toPoint();

                const QPointF p = ev->touchPoints().at(0).pos().toPoint();

                if ((startPos - p).manhattanLength() > panBeginRadius) {

                    d->delayManager->replay();

                    consume = false;

                    reset();

                } else {

                    d->lastPosition = QCursor::pos();

                }

            } else {

                d->delayManager->clear();

                QPointF mousePos = QCursor::pos();

                QPointF dist = mousePos - d->lastPosition;

                d->lastPosition = mousePos;

                d->lastOffset = d->offset;

                d->offset = QSizeF(dist.x(), dist.y());

                d->totalOffset += d->offset;

                updateState(Qt::GestureUpdated);

            }

        } else if (state() == Qt::NoGesture) {

            d->delayManager->replay();

            consume = false;

            reset();

        }

        break;}

    case QEvent::MouseButtonPress:

    case QEvent::MouseMove:

    case QEvent::MouseButtonRelease:

        if (d->delayManager->isEnabled())

            consume = d->delayManager->append(d->gestureTarget, *event);

        break;

    default:

        return false;

    }

#else

    Q_UNUSED(event);

#endif

    return QGestureRecognizer::Ignore;

}

    */

QT_END_NAMESPACE