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#include "qsensorbackend.h"

#include "qsensor_p.h"

#include <QDebug>

QTM_BEGIN_NAMESPACE

/*!

    \class QSensorBackend

    \ingroup sensors_backend

    \brief The QSensorBackend class is a sensor implementation.

    Sensors on a device will be represented by sub-classes of

    QSensorBackend.

*/

/*!

    \internal

*/

QSensorBackend::QSensorBackend(QSensor *sensor)

    : m_sensor(sensor)

{

}

/*!

    \internal

*/

QSensorBackend::~QSensorBackend()

{

}

/*!

    Notify the QSensor class that a new reading is available.

*/

void QSensorBackend::newReadingAvailable()

{

    QSensorPrivate *d = m_sensor->d_func();

    // Copy the values from the device reading to the filter reading

    d->filter_reading->copyValuesFrom(d->device_reading);

    for (QFilterList::const_iterator it = d->filters.constBegin(); it != d->filters.constEnd(); ++it) {

        QSensorFilter *filter = (*it);

        if (!filter->filter(d->filter_reading))

            return;

    }

    // Copy the values from the filter reading to the cached reading

    d->cache_reading->copyValuesFrom(d->filter_reading);

    Q_EMIT m_sensor->readingChanged();

}

/*!

    \fn QSensorBackend::start()

    Start reporting values.

*/

/*!

    \fn QSensorBackend::stop()

    Stop reporting values.

*/

/*!

    If the backend has lost its reference to the reading

    it can call this method to get the address.

    Note that you will need to down-cast to the appropriate

    type.

    \sa setReading()

*/

QSensorReading *QSensorBackend::reading() const

{

    QSensorPrivate *d = m_sensor->d_func();

    return d->device_reading;

}

/*!

    \fn QSensorBackend::sensor() const

    Returns the sensor front end associated with this backend.

*/

/*!

    \fn QSensorBackend::setReading(T *reading)

    This function is called to initialize the \a reading

    classes used for a sensor.

    If your backend has already allocated a reading you

    should pass the address of this to the function.

    Otherwise you should pass 0 and the function will

    return the address of the reading your backend

    should use when it wants to notify the sensor API

    of new readings.

    Note that this is a template function so it should

    be called with the appropriate type.

    \code

    class MyBackend : public QSensorBackend

    {

        QAccelerometerReading m_reading;

    public:

        MyBackend(QSensor *sensor)

            : QSensorBackend(sensor)

        {

            setReading<QAccelerometerReading>(&m_reading);

        }

        ...

    \endcode

    Note that this function must be called or you will

    not be able to send readings to the front end.

    If you do not wish to store the address of the reading

    you may use the reading() method to get it again later.

    \code

    class MyBackend : public QSensorBackend

    {

    public:

        MyBackend(QSensor *sensor)

            : QSensorBackend(sensor)

        {

            setReading<QAccelerometerReading>(0);

        }

        void poll()

        {

            qtimestamp timestamp;

            qreal x, y, z;

            ...

            QAccelerometerReading *reading = static_cast<QAccelerometerReading*>(reading());

            reading->setTimestamp(timestamp);

            reading->setX(x);

            reading->setY(y);

            reading->setZ(z);

        }

        ...

    \endcode

    \sa reading()

*/

/*!

    \internal

*/

void QSensorBackend::setReadings(QSensorReading *device, QSensorReading *filter, QSensorReading *cache)

{

    QSensorPrivate *d = m_sensor->d_func();

    d->device_reading = device;

    d->filter_reading = filter;

    d->cache_reading = cache;

}

/*!

    Add a data rate (consisting of \a min and \a max values) for the sensor.

    Note that this function should be called from the constructor so that the information

    is available immediately.

    \sa QSensor::availableDataRates

*/

void QSensorBackend::addDataRate(qreal min, qreal max)

{

    QSensorPrivate *d = m_sensor->d_func();

    d->availableDataRates << qrange(min, max);

}

/*!

    Set the data rates for the sensor based on \a otherSensor.

    This is designed for sensors that are based on other sensors.

    \code

    setDataRates(otherSensor);

    \endcode

    Note that this function should be called from the constructor so that the information

    is available immediately.

    \sa QSensor::availableDataRates, addDataRate()

*/

void QSensorBackend::setDataRates(const QSensor *otherSensor)

{

    if (!otherSensor) {

        qWarning() << "ERROR: Cannot call QSensorBackend::setDataRates with 0";

        return;

    }

    if (otherSensor->identifier().isEmpty()) {

        qWarning() << "ERROR: Cannot call QSensorBackend::setDataRates with an invalid sensor";

        return;

    }

    QSensorPrivate *d = m_sensor->d_func();

    d->availableDataRates = otherSensor->availableDataRates();

    d->dataRate = otherSensor->dataRate();

}

/*!

    Add an output range (consisting of \a min, \a max values and \a accuracy) for the sensor.

    Note that this function should be called from the constructor so that the information

    is available immediately.

    \sa QSensor::outputRange, QSensor::outputRanges

*/

void QSensorBackend::addOutputRange(qreal min, qreal max, qreal accuracy)

{

    QSensorPrivate *d = m_sensor->d_func();

    qoutputrange details = {min, max, accuracy};

    d->outputRanges << details;

}

/*!

    Set the \a description for the sensor.

    Note that this function should be called from the constructor so that the information

    is available immediately.

*/

void QSensorBackend::setDescription(const QString &description)

{

    QSensorPrivate *d = m_sensor->d_func();

    d->description = description;

}

/*!

    Inform the front end that the sensor has stopped.

    This can be due to start() failing or for some

    unexpected reason (eg. hardware failure).

    Note that the front end must call QSensor::isActive() to see if

    the sensor has stopped. If the sensor has stopped due to an error

    the sensorError() function should be called to notify the class

    of the error condition.

*/

void QSensorBackend::sensorStopped()

{

    QSensorPrivate *d = m_sensor->d_func();

    d->active = false;

}

/*!

    Inform the front end that the sensor is busy.

    This implicitly calls sensorStopped() and

    is typically called from start().

    Note that the front end must call QSensor::isBusy() to see if

    the sensor is busy. If the sensor has stopped due to an error

    the sensorError() function should be called to notify the class

    of the error condition.

*/

void QSensorBackend::sensorBusy()

{

    QSensorPrivate *d = m_sensor->d_func();

    d->active = false;

    d->busy = true;

}

/*!

    Inform the front end that a sensor error occurred.

    Note that this only reports an \a error code. It does

    not stop the sensor.

    \sa sensorStopped()

*/

void QSensorBackend::sensorError(int error)

{

    QSensorPrivate *d = m_sensor->d_func();

    d->error = error;

    Q_EMIT m_sensor->sensorError(error);

}

#include "moc_qsensorbackend.cpp"

QTM_END_NAMESPACE