path: root/src/sensors/qsensor.h

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#ifndef QSENSOR_H
#define QSENSOR_H

#include <QtCore/QObject>
#include <QtCore/QByteArray>
#include <QtCore/QMetaType>
#include <QtCore/QVariant>
#include <QtCore/QPair>

QT_BEGIN_NAMESPACE

class QSensorPrivate;
class QSensorBackend;
class QSensorReading;
class QSensorReadingPrivate;
class QSensorFilter;

#ifdef Q_QDOC
typedef quint64 qtimestamp;
#else
class qtimestamp
{
public:
    qtimestamp() : value() {}
    qtimestamp(quint64 timestamp) : value(timestamp) {}
    operator quint64() const { return value; }
private:
    quint64 value;
};
#endif

typedef QPair<int,int> qrange;
typedef QList<qrange> qrangelist;
struct qoutputrange
{
    qreal minimum;
    qreal maximum;
    qreal accuracy;
};
typedef QList<qoutputrange> qoutputrangelist;

class Q_SENSORS_EXPORT QSensor : public QObject
{
    friend class QSensorBackend;

    Q_OBJECT
    Q_PROPERTY(QByteArray sensorid READ identifier WRITE setIdentifier)
    Q_PROPERTY(QByteArray type READ type)
    Q_PROPERTY(bool connectedToBackend READ isConnectedToBackend)
    Q_PROPERTY(qrangelist availableDataRates READ availableDataRates)
    Q_PROPERTY(int dataRate READ dataRate WRITE setDataRate)
    Q_PROPERTY(QSensorReading* reading READ reading NOTIFY readingChanged)
    Q_PROPERTY(bool busy READ isBusy)
    Q_PROPERTY(bool active READ isActive WRITE setActive NOTIFY activeChanged)
    Q_PROPERTY(qoutputrangelist outputRanges READ outputRanges)
    Q_PROPERTY(int outputRange READ outputRange WRITE setOutputRange)
    Q_PROPERTY(QString description READ description)
    Q_PROPERTY(int error READ error NOTIFY sensorError)
#ifdef Q_QDOC
    Q_PROPERTY(int maxBufferSize)
    Q_PROPERTY(int efficientBufferSize)
    Q_PROPERTY(int bufferSize)
#endif
public:
    explicit QSensor(const QByteArray &type, QObject *parent = 0);
    virtual ~QSensor();

    QByteArray identifier() const;
    void setIdentifier(const QByteArray &identifier);

    QByteArray type() const;

    Q_INVOKABLE bool connectToBackend();
    bool isConnectedToBackend() const;

    bool isBusy() const;

    void setActive(bool active);
    bool isActive() const;

    qrangelist availableDataRates() const;
    int dataRate() const;
    void setDataRate(int rate);

    qoutputrangelist outputRanges() const;
    int outputRange() const;
    void setOutputRange(int index);

    QString description() const;
    int error() const;

    // Filters modify the reading
    void addFilter(QSensorFilter *filter);
    void removeFilter(QSensorFilter *filter);
    QList<QSensorFilter*> filters() const;

    // The readings are exposed via this object
    QSensorReading *reading() const;

    // Information about available sensors
    // These functions are implemented in qsensormanager.cpp
    static QList<QByteArray> sensorTypes();
    static QList<QByteArray> sensorsForType(const QByteArray &type);
    static QByteArray defaultSensorForType(const QByteArray &type);

public Q_SLOTS:
    // Start receiving values from the sensor
    bool start();

    // Stop receiving values from the sensor
    void stop();

Q_SIGNALS:
    void busyChanged();
    void activeChanged();
    void readingChanged();
    void sensorError(int error);
    void availableSensorsChanged();

protected:
    // called by the back end
    QSensorPrivate *d_func() const { return d.data(); }

private:
    void registerInstance();

    QScopedPointer<QSensorPrivate> d;
    Q_DISABLE_COPY(QSensor)
};

class Q_SENSORS_EXPORT QSensorFilter
{
    friend class QSensor;
public:
    virtual bool filter(QSensorReading *reading) = 0;
protected:
    QSensorFilter();
    ~QSensorFilter();
    virtual void setSensor(QSensor *sensor);
    QSensor *m_sensor;
};

class Q_SENSORS_EXPORT QSensorReading : public QObject
{
    friend class QSensorBackend;

    Q_OBJECT
    Q_PROPERTY(qtimestamp timestamp READ timestamp)
public:
    virtual ~QSensorReading();

    qtimestamp timestamp() const;
    void setTimestamp(qtimestamp timestamp);

    // Access properties of sub-classes by numeric index
    // For name-based access use QObject::property()
    int valueCount() const;
    QVariant value(int index) const;

protected:
    explicit QSensorReading(QObject *parent, QSensorReadingPrivate *d);
    QScopedPointer<QSensorReadingPrivate> *d_ptr() { return &d; }
    virtual void copyValuesFrom(QSensorReading *other);

private:
    QScopedPointer<QSensorReadingPrivate> d;
    Q_DISABLE_COPY(QSensorReading)
};

#define DECLARE_READING(classname)\
        DECLARE_READING_D(classname, classname ## Private)

#define DECLARE_READING_D(classname, pclassname)\
    public:\
        classname(QObject *parent = 0);\
        virtual ~classname();\
        void copyValuesFrom(QSensorReading *other);\
    private:\
        QScopedPointer<pclassname> d;

#define IMPLEMENT_READING(classname)\
        IMPLEMENT_READING_D(classname, classname ## Private)

#define IMPLEMENT_READING_D(classname, pclassname)\
    classname::classname(QObject *parent)\
        : QSensorReading(parent, 0)\
        , d(new pclassname)\
        {}\
    classname::~classname() {}\
    void classname::copyValuesFrom(QSensorReading *_other)\
    {\
        /* No need to verify types, only called by QSensorBackend */\
        classname *other = static_cast<classname *>(_other);\
        pclassname *my_ptr = d.data();\
        pclassname *other_ptr = other->d.data();\
        /* Do a direct copy of the private class */\
        *(my_ptr) = *(other_ptr);\
        /* We need to copy the parent too */\
        QSensorReading::copyValuesFrom(_other);\
    }


Q_DECLARE_METATYPE(qtimestamp)
Q_DECLARE_METATYPE(qrange)
Q_DECLARE_METATYPE(qrangelist)
Q_DECLARE_METATYPE(qoutputrangelist)

QT_END_NAMESPACE
#endif