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#include "qsensor.h"

#include "qsensor_p.h"

#include "qsensorbackend.h"

#include "qsensormanager.h"

#include <QDebug>

#include <QMetaProperty>

QTM_BEGIN_NAMESPACE

/*!

    \typedef qtimestamp

    \relates QSensor

    Sensor timestamps are represented by this typedef which is a 64 bit unsigned integer.

    Timestamps values are microseconds since a fixed point.

    You can use timestamps to see how far apart two sensor readings are.

    Note that sensor timestamps from different sensors may not be directly

    comparable (as they may choose different fixed points for their reference).

*/

// A bit of a hack to call qRegisterMetaType when the library is loaded.

static int qtimestamp_id = qRegisterMetaType<QtMobility::qtimestamp>("QtMobility::qtimestamp");

// =====================================================================

/*!

    \class QSensor

    \ingroup sensors_main

    \preliminary

    \brief The QSensor class represents a single hardware sensor.

    The life cycle of a sensor is typically:

    \list

    \o Create a sub-class of QSensor on the stack or heap.

    \o Setup as required by the application.

    \o Start receiving values.

    \o Sensor data is used by the application.

    \o Stop receiving values.

    \endlist

    The sensor data is delivered via QSensorData and its sub-classes.

*/

/*!

*/

    : QObject(parent)

    , d(new QSensorPrivate)

{

}

/*!

    Destroy the sensor. Stops the sensor if it has not already been stopped.

*/

QSensor::~QSensor()

{

    stop();

    Q_FOREACH (QSensorFilter *filter, d->filters)

        filter->setSensor(0);

    delete d->backend;

    d->backend = 0;

    // owned by the backend

    d->device_reading = 0;

    d->filter_reading = 0;

    d->cache_reading = 0;

}

/*!

    \brief a value indicating if the sensor has connected to a backend.

    A sensor that has not been connected to a backend cannot do anything useful.

*/

{

    return (d->backend != 0);

}

/*!

    \property QSensor::sensorid

    \brief the backend identifier for the sensor.

    Note that the identifier is filled out automatically

    when the sensor is connected to a backend. If you want

    to connect a specific backend, you should call

*/

QByteArray QSensor::identifier() const

{

    return d->identifier;

}

void QSensor::setIdentifier(const QByteArray &identifier)

{

    d->identifier = identifier;

}

/*!

    \property QSensor::type

    \brief the type of the sensor.

*/

QByteArray QSensor::type() const

{

    return d->type;

}

/*!

    Try to connect to a sensor backend.

    Returns true if a suitable backend could be found, false otherwise.

    The type must be set before calling this method if you are using QSensor directly.

*/

{

    if (d->backend)

        return true;

    d->backend = QSensorManager::createBackend(this);

    return (d->backend != 0);

}

/*!

*/

bool QSensor::isActive() const

{

    return d->active;

}

{

    }

}

/*!

*/

{

    if (d->active)

    d->active = true;

    d->backend->start();

}

/*!

    Stop retrieving values from the sensor.

*/

void QSensor::stop()

{

    if (!d->active || !d->backend)

        return;

    d->active = false;

    d->backend->stop();

}

/*!

    \property QSensor::reading

    \brief the reading class.

    The reading class provides access to sensor readings.

*/

QSensorReading *QSensor::reading() const

{

    return d->cache_reading;

}

/*!

    Add a \a filter to the sensor.

    The sensor does not take ownership of the filter.

    QSensorFilter will inform the sensor if it is destroyed.

    \sa QSensorFilter

*/

void QSensor::addFilter(QSensorFilter *filter)

{

    d->filters << filter;

}

/*!

    Remove \a filter from the sensor.

    \sa QSensorFilter

*/

void QSensor::removeFilter(QSensorFilter *filter)

{

    d->filters.removeOne(filter);

    filter->setSensor(0);

}

/*!

    \fn QSensor::d_func() const

    \internal

*/

/*!

    \fn QSensor::readingChanged()

    This signal is emitted when the reading has changed.

*/

// =====================================================================

/*!

    \class QSensorFilter

    \ingroup sensors_main

    \preliminary

    \brief The QSensorFilter class provides an efficient

           callback facility for asynchronous notifications of

           sensor changes.

    Some sensors (eg. the accelerometer) are often accessed very frequently.

    This may be slowed down by the use of signals and slots.

    The QSensorFilter interface provides a more efficient way for the

    sensor to notify your class that the sensor has changed.

    Additionally, multiple filters can be added to a sensor. They are called

    in order and each filter has the option to modify the values in the reading

    or to suppress the reading altogether.

    Note that the values in the class returned by QSensor::reading() will

    not be updated until after the filters have been run.

    \sa filter()

*/

/*!

    \internal

*/

QSensorFilter::QSensorFilter()

    : m_sensor(0)

{

}

/*!

    Notifies the attached sensor (if any) that the filter is being destroyed.

*/

QSensorFilter::~QSensorFilter()

{

    if (m_sensor)

        m_sensor->removeFilter(this);

}

/*!

    \fn QSensorFilter::filter(QSensorReading *reading)

    This function is called when the sensor \a reading changes.

    The filter can modify the reading.

    Returns true to allow the next filter to receive the value.

    If this is the last filter, returning true causes the signal

    to be emitted and the value is stored in the sensor.

    Returns false to drop the reading.

*/

/*!

    \internal

*/

void QSensorFilter::setSensor(QSensor *sensor)

{

    m_sensor = sensor;

}