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#include "n900accelerometer.h"

#include <QFile>

#include <QDebug>

#include <time.h>

#include <stdio.h>

char const * const n900accelerometer::id("n900.accelerometer");

char const * const n900accelerometer::filename("/sys/class/i2c-adapter/i2c-3/3-001d/coord");

char const * const n900accelerometer::range("/sys/class/i2c-adapter/i2c-3/3-001d/scale");

char const * const n900accelerometer::rate("/sys/class/i2c-adapter/i2c-3/3-001d/rate");

n900accelerometer::n900accelerometer(QSensor *sensor)

    : n900filebasedsensor(sensor)

{

    setReading<QAccelerometerReading>(&m_reading);

    // Details derived from the kernel driver

    addDataRate(100, 100); // 100Hz

    addOutputRange(-22.418, 22.418, 0.17651); // 2G

    setDescription(QLatin1String("lis302dl"));

}

void n900accelerometer::start()

{

    if (!QFile::exists(QLatin1String(filename)))

        goto error;

    n900filebasedsensor::start();

    return;

error:

    sensorStopped();

}

void n900accelerometer::poll()

{

    // Note that this is a rather inefficient way to generate this data.

    // Ideally the kernel would scale the hardware's values to m/s^2 for us

    // and give us a timestamp along with that data.

    FILE *fd = fopen(filename, "r");

    if (!fd) return;

    int x, y, z;

    int rs = fscanf(fd, "%i %i %i", &x, &y, &z);

    fclose(fd);

    if (rs != 3) return;

    // Convert from milli-Gs to meters per second per second

    // Using 1 G = 9.80665 m/s^2

    qreal ax = x * 0.00980665;

    qreal ay = y * -0.00980665;

    qreal az = z * -0.00980665;

    m_reading.setTimestamp(clock());

    m_reading.setX(ax);

    m_reading.setY(ay);

    m_reading.setZ(az);

    newReadingAvailable();

}