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#include "androidcompass.h"

#include <QDebug>
#include <qmath.h>
#include "androidjnisensors.h"


class AndroidAccelerometerListener : public AndroidSensors::AndroidSensorsListenerInterface
{
public:

    AndroidAccelerometerListener(AndroidCompass *parent)
        : accuracy(0), m_compass(parent)
    {
        memset(reading, 0, sizeof(reading));
    }

    void start(int dataRate)
    {
        AndroidSensors::registerListener(AndroidSensors::TYPE_ACCELEROMETER, this, dataRate);
    }

    void stop()
    {
        AndroidSensors::unregisterListener(AndroidSensors::TYPE_ACCELEROMETER, this);
    }

    void onAccuracyChanged(jint value) override
    {
        accuracy = value;
    }

    void onSensorChanged(jlong /*timestamp*/, const jfloat *values, uint size) override
    {
        if (size < 3)
            return;
        reading[0] = values[0];
        reading[1] = values[1];
        reading[2] = values[2];
        m_compass->testStuff();
    }

    jfloat reading[3];
    jint accuracy;

private:
    AndroidCompass *m_compass;
};

class AndroidMagnetometerListener : public AndroidSensors::AndroidSensorsListenerInterface
{
public:
    AndroidMagnetometerListener(AndroidCompass *parent)
        : accuracy(0), m_compass(parent)
    {
        memset(reading, 0, sizeof(reading));
    }

    void start(int dataRate)
    {
        AndroidSensors::registerListener(AndroidSensors::TYPE_MAGNETIC_FIELD, this, dataRate);
    }

    void stop()
    {
        AndroidSensors::unregisterListener(AndroidSensors::TYPE_MAGNETIC_FIELD, this);
    }

    void onAccuracyChanged(jint value) override
    {
        accuracy = value;
    }

    void onSensorChanged(jlong /*timestamp*/, const jfloat *values, uint size) override
    {
        if (size < 3)
            return;
        reading[0] = values[0];
        reading[1] = values[1];
        reading[2] = values[2];
        m_compass->testStuff();
    }

    jfloat reading[3];
    jint accuracy;
private:
    AndroidCompass *m_compass;
};

char const * const AndroidCompass::id("android.synthetic.compass");

AndroidCompass::AndroidCompass(QSensor *sensor)
    : QSensorBackend(sensor), m_accelerometerListener(0), m_magnetometerListener(0), m_isStarted(false)
{
    setReading<QCompassReading>(&m_reading);
    m_isStarted = false;
}

AndroidCompass::~AndroidCompass()
{
    if (m_isStarted)
        stop();
    delete m_accelerometerListener;
    delete m_magnetometerListener;
}

void AndroidCompass::start()
{
    if (!m_accelerometerListener)
        m_accelerometerListener = new AndroidAccelerometerListener(this);
    if (!m_magnetometerListener)
        m_magnetometerListener = new AndroidMagnetometerListener(this);
    m_accelerometerListener->start(sensor()->dataRate());
    m_magnetometerListener->start(sensor()->dataRate());

    m_isStarted = true;
}

void AndroidCompass::stop()
{
    if (m_isStarted) {
        m_isStarted = false;
        m_accelerometerListener->stop();
        m_magnetometerListener->stop();
    }
}

void AndroidCompass::testStuff()
{
    if (!m_accelerometerListener || !m_magnetometerListener)
        return;
    qreal azimuth = AndroidSensors::getCompassAzimuth(m_accelerometerListener->reading, m_magnetometerListener->reading);

    m_reading.setAzimuth(qRadiansToDegrees(azimuth));
    const qreal accuracyValue = (m_accelerometerListener->accuracy + m_magnetometerListener->accuracy) / 6;
    m_reading.setCalibrationLevel(accuracyValue);
    newReadingAvailable();
}