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#include "qsensor2tilt.h"
#define _USE_MATH_DEFINES
#include <qmath.h>
#include <QtCore/QDebug>
#include <QtCore/QStringList>

#define MAXRATE 30

QT_BEGIN_NAMESPACE

/*!
    \qmlclass TiltSensor QSensor2Tilt
    \inherits QtSensors5::Sensor
    \inqmlmodule QtSensors 5
    \ingroup qml-QtSensors5
    \since QtSensors 5.0
    \brief The TiltSensor element provides tilt datas from x and y rotation of the device using the accelerometer sensor.

    This element is part of the \bold{QtSensors 5} module.
*/
QSensor2Tilt::QSensor2Tilt(QObject* parent)
    : qsensor2common(parent)
    , _yRotation(0)
    , _xRotation(0)
    , _radAccuracy(M_PI / 180)
    , _unit(QSensor2Tilt::Radians)
    , _pitch(0)
    , _roll(0)
    , _calibratedPitch(0)
    , _calibratedRoll(0)
    , _speed(QSensor2Tilt::Slow)
{
    _accel = new QAccelerometer(this);
    _accel->addFilter(this);
}

QSensor2Tilt::~QSensor2Tilt()
{
}

int searchDataRate(const QList<int>& datarates, int value)
{
    int l = 0;
    int r = datarates.count() - 1;
    int m = (l + r) / 2;

    while (l <= r) {
        m = (l + r) / 2;
        if (datarates[m] == value)
          break;
        else if (datarates[m] < value)
          r = m - 1;
        else
          l = m + 1;
    }
    if (m > 0){
        int ddr = datarates[m - 1];
        ddr -= value;
        int ddr1 = datarates[m] - value;
        if (ddr1 < 0) ddr1 = -ddr1;
        if (ddr < ddr1)
            return datarates[m - 1];
    }

    return datarates[m];
}

QMap<QSensor2Tilt::Speed, int> QSensor2Tilt::dataRate()
{
    return _dataRate;
}

void QSensor2Tilt::createRunModeDataRateMap()
{
    _dataRate.clear();
    qrangelist rl = _accel->availableDataRates();

    //1. make a list of all available datarates
    QList<int> dr;
    foreach (const qrange &r, rl) {
        for (int i = r.first; i <= r.second; i++){
            if (i <= MAXRATE){
                if (!dr.contains(i))
                   dr.append(i);
            }
        }
    }

    //2. Sort the list
    if (dr.count() > 0){
        qSort(dr.begin(), dr.end(), qGreater<int>());
        _dataRate.insert(QSensor2Tilt::Slow, searchDataRate(dr, 2));
        _dataRate.insert(QSensor2Tilt::Medium, searchDataRate(dr, 10));
        _dataRate.insert(QSensor2Tilt::Fast, searchDataRate(dr, 20));
    }
}

/*!
    \qmlproperty enumeration QtSensors5::TiltSensor::speed
    Holds the speed that the sensor should be run at.
    Default is Slow.

    \table
    \row
        \o TiltSensor.Slow
        \o The sensor runs in slow mode.
        \o Closest available datarate at 2Hz.
    \row
        \o TiltSensor.Medium
        \o The sensor runs in medium mode.
        \o Closest available datarate at 10Hz.
    \row
        \o TiltSensor.Fast
        \o The sensor runs in fast mode.
        \o Closest available datarate at 20Hz.
    \endtable
*/
QSensor2Tilt::Speed QSensor2Tilt::speed()
{
    return _speed;
}

void QSensor2Tilt::setSpeed(const QSensor2Tilt::Speed val)
{
    if (_dataRate.keys().contains(val)){
        if (_dataRate.value(val) != _accel->dataRate()){
            _accel->setDataRate(_dataRate.value(val));
            emit speedChanged();
        }
    }
    _speed = val;
}

void QSensor2Tilt::setEnabled(const bool val)
{
    bool active = enabled();
    if (active != val){
        if (val){
            bool readDatarateMap = !_accel->isConnectedToBackend();
            bool ret = _accel->start();
            if (!ret)
                qWarning() << "couldn't start the sensor.";
            else if (readDatarateMap){
                 createRunModeDataRateMap();
                 setSpeed(_speed);
             }
        }
        else
            _accel->stop();
        emit enabledChanged();
    }
}

/*!
    \target unit_property
    \qmlproperty enumeration QtSensors5::TiltSensor::unit
    Returns the unit of the rotation which can be one of:
    \table
    \row
        \o TiltSensor.Radians
        \o The unit of the rotation angle is radians.
    \row
        \o TiltSensor.Degrees
        \o The unit of the rotation angle is degrees.
    \endtable
*/
QSensor2Tilt::Unit QSensor2Tilt::unit()
{
    return _unit;
}

void QSensor2Tilt::setUnit(const QSensor2Tilt::Unit val)
{
    if (_unit != val){
        _unit = val;
        emit unitChanged();
    }
}


/*!
    \qmlproperty real QtSensors5::TiltSensor::yRotation
    Holds the rotation arround the y axis.

    \table
    \row
        \o
        \image YAngle.gif
        \o
        \image YAngleNegative.gif
    \endtable
*/
qreal QSensor2Tilt::yRotation()
{
    if (_unit == QSensor2Tilt::Degrees)
        return _yRotation * 180 / M_PI;

    return _yRotation;
}

/*!
    \qmlproperty real QtSensors5::TiltSensor::xRotation
    Holds the rotation arround the x axis.
    \table
    \row
        \o
        \image XAngle.gif
        \o
        \image XAngleNegative.gif
    \endtable
*/
qreal QSensor2Tilt::xRotation()
{
    if (_unit == QSensor2Tilt::Degrees)
        return _xRotation * 180 / M_PI;

    return _xRotation;
}

/*
  Angle between Ground and X
                |            Ax           |
  pitch = arctan| ----------------------- |
                |  sqrt(Ay * Ay + Az * Az)|
*/
inline qreal calcPitch(double Ax, double Ay, double Az)
{
    return (float)-qAtan2(Ax, sqrt(Ay * Ay + Az * Az));
}

/*
  Angle between Ground and Y
                |            Ay           |
   roll = arctan| ----------------------- |
                |  sqrt(Ax * Ax + Az * Az)|
*/
inline qreal calcRoll(double Ax, double Ay, double Az)
{
    return (float)qAtan2(Ay, (sqrt(Ax * Ax + Az * Az)));
}

/*!
    \qmlproperty real QtSensors5::TiltSensor::accuracy
    This property contains the accuracy (in degrees) in which the rotation should be measured.
    This can be used to minimize signal emiting and therefore saving of performance.
    Default value is 1 degree.
    The accuracy value is unsigned and works clockwise and anti-clockwise in X and Y axis rotation directions.
    Accuracy range can be 0 to 90 degrees.


    E.g.


    Accuracy 5.5 will notify the client application about an rotation change only if the rotation angle over the X and / or Y axis was changed by 5.5 or more degrees clockwise or anti-clockwise.

    \table
    \header \o Rotation \o notify application \o reason
    \row \o 0.2424   \o no   \o
    \row \o 4.34234  \o no   \o
    \row \o 5.23423  \o no   \o
    \row \o 6.34324  \o yes  \o because 6.34324 >= 5.5
    \row \o 7.43264  \o no   \o
    \row \o 8.24504  \o no   \o
    \row \o 9.34653  \o no   \o
    \row \o 10.23476 \o no   \o
    \row \o 11.43565 \o no   \o
    \row \o 12.45645 \o yes  \o because 12.45645 - 6.34324 = 6.11321 >= 5.5
    \endtable
*/
/*!
    \qmlsignal QtSensors5::TiltSensor::tiltChanged(real deltaX, real deltaY)
    This signal is emitted whenever the change from at leat one of the rotation values was higher than the accuracy.
    The angle value is based on the specified unit (Degree or Radian).

    \sa {QtSensors5::TiltSensor::unit} {TiltSensor.unit}
*/
qreal QSensor2Tilt::accuracy()
{
    //return in degree
    return 180 * _radAccuracy / M_PI;
}

void QSensor2Tilt::setAccuracy(qreal val)
{
    //save in rad to save convertion calc in filter function
    if (val <= 90 && val >= 0)
      _radAccuracy = M_PI * val / 180;
}

/*!
    \qmlmethod void QtSensors5::TiltSensor::calibrate()
    The call of this function calibrates the tilt from x and y to the current position.
*/
void QSensor2Tilt::calibrate()
{
    _calibratedPitch = _pitch;
    _calibratedRoll = _roll;
#ifdef LOGCALIBRATION
    qDebug() << "--------- calibrate --------";
    qDebug() << "_calibratedPitch: " << _calibratedPitch;
    qDebug() << "_calibratedRoll: " << _calibratedRoll;
    qDebug() << "----------------------------";
#endif
}

/*!
    \qmlproperty real QtSensors5::TiltSensor::settings
    This property contains the setting of the current state.
    It can be used for saving and reloading previously saved calibrations.
*/
QByteArray QSensor2Tilt::settings() const
{
    QByteArray arr;
    arr.append(QString::number((double)_calibratedPitch));
    arr.append(";");
    arr.append(QString::number((double)_calibratedRoll));
    return arr;
}

void QSensor2Tilt::setSettings(const QByteArray val)
{
    QString str(val);
    if (str.indexOf(";") > 0){
        QStringList strlist = str.split(";");
        if (strlist.length() == 2){
            _calibratedPitch = strlist.at(0).toDouble();
            _calibratedRoll = strlist.at(1).toDouble();
        }
    }
}

bool QSensor2Tilt::filter(QAccelerometerReading* reading)
{
    /*
      z  y
      | /
      |/___ x
    */

    qreal ax = reading->x();
    qreal ay = reading->y();
    qreal az = reading->z();
#ifdef LOGCALIBRATION
    qDebug() << "------------ new value -----------";
    qDebug() << "old _pitch: " << _pitch;
    qDebug() << "old _roll: " << _roll;
    qDebug() << "_calibratedPitch: " << _calibratedPitch;
    qDebug() << "_calibratedRoll: " << _calibratedRoll;
#endif
    _pitch = calcPitch(ax, ay, az);
    _roll  = calcRoll (ax, ay, az);
#ifdef LOGCALIBRATION
    qDebug() << "_pitch: " << _pitch;
    qDebug() << "_roll: " << _roll;
#endif
    qreal xrot = _roll - _calibratedRoll;
    qreal yrot = _pitch - _calibratedPitch;
    //get angle beteen 0 and 180 or 0 -180
    qreal aG = 1 * sin(xrot);
    qreal aK = 1 * cos(xrot);
    xrot = qAtan2(aG, aK);
    if (xrot > M_PI_2)
        xrot = M_PI - xrot;
    else if (xrot < -M_PI_2)
        xrot = -(M_PI + xrot);
    aG = 1 * sin(yrot);
    aK = 1 * cos(yrot);
    yrot = qAtan2(aG, aK);
    if (yrot > M_PI_2)
        yrot = M_PI - yrot;
    else if (yrot < -M_PI_2)
        yrot = -(M_PI + yrot);


#ifdef LOGCALIBRATION
    qDebug() << "new xrot: " << xrot;
    qDebug() << "new yrot: " << yrot;
    qDebug() << "----------------------------------";
#endif
    qreal dxrot = xrot - _xRotation;
    qreal dyrot = yrot - _yRotation;
    if (dxrot < 0) dxrot = -dxrot;
    if (dyrot < 0) dyrot = -dyrot;

    bool change = false;
    if (dxrot >= _radAccuracy){
        _xRotation = xrot;
        emit xRotationChanged();
        change = true;
    }
    if (dyrot >= _radAccuracy){
        _yRotation = yrot;
        emit yRotationChanged();
        change = true;
    }
    if (change){
        if (_unit == QSensor2Tilt::Degrees)
            emit tiltChanged(dxrot * 180 / M_PI, dyrot * 180 / M_PI);
        else
            emit tiltChanged(dxrot, dyrot);
    }
    return false;
}

QT_END_NAMESPACE