/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtSensors module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
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** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
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** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QSENSOR_H
#define QSENSOR_H

#include <QtSensors/qsensorsglobal.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;

using qrange = QPair<int,int>;
using qrangelist = QList<qrange>;

struct qoutputrange
{
    qreal minimum;
    qreal maximum;
    qreal accuracy;
};

using qoutputrangelist = QList<qoutputrange>;

class Q_SENSORS_EXPORT QSensor : public QObject
{
    friend class QSensorBackend;
    Q_OBJECT
    Q_PROPERTY(QByteArray identifier READ identifier WRITE setIdentifier NOTIFY identifierChanged)
    Q_PROPERTY(QByteArray type READ type CONSTANT)
    Q_PROPERTY(bool connectedToBackend READ isConnectedToBackend)
    Q_PROPERTY(qrangelist availableDataRates READ availableDataRates)
    Q_PROPERTY(int dataRate READ dataRate WRITE setDataRate NOTIFY dataRateChanged)
    Q_PROPERTY(QSensorReading* reading READ reading NOTIFY readingChanged)
    Q_PROPERTY(bool busy READ isBusy NOTIFY busyChanged)
    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)
    Q_PROPERTY(bool alwaysOn READ isAlwaysOn WRITE setAlwaysOn NOTIFY alwaysOnChanged)
    Q_PROPERTY(bool skipDuplicates READ skipDuplicates WRITE setSkipDuplicates NOTIFY skipDuplicatesChanged)
    Q_PROPERTY(AxesOrientationMode axesOrientationMode READ axesOrientationMode WRITE setAxesOrientationMode NOTIFY axesOrientationModeChanged)
    Q_PROPERTY(int currentOrientation READ currentOrientation NOTIFY currentOrientationChanged)
    Q_PROPERTY(int userOrientation READ userOrientation WRITE setUserOrientation NOTIFY userOrientationChanged)
    Q_PROPERTY(int maxBufferSize READ maxBufferSize NOTIFY maxBufferSizeChanged)
    Q_PROPERTY(int efficientBufferSize READ efficientBufferSize NOTIFY efficientBufferSizeChanged)
    Q_PROPERTY(int bufferSize READ bufferSize WRITE setBufferSize NOTIFY bufferSizeChanged)
public:
    enum Feature {
        Buffering,
        AlwaysOn,
        GeoValues,
        FieldOfView,
        AccelerationMode,
        SkipDuplicates,
        AxesOrientation,
        PressureSensorTemperature,
        Reserved = 257 // Make sure at least 2 bytes are used for the enum to avoid breaking BC later
    };
    Q_ENUM(Feature)

    // Keep in sync with QmlSensor::AxesOrientationMode
    enum AxesOrientationMode {
        FixedOrientation,
        AutomaticOrientation,
        UserOrientation
    };
    Q_ENUM(AxesOrientationMode)

    explicit QSensor(const QByteArray &type, QObject *parent = nullptr);
    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;

    bool isAlwaysOn() const;
    void setAlwaysOn(bool alwaysOn);

    bool skipDuplicates() const;
    void setSkipDuplicates(bool skipDuplicates);

    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);

    Q_INVOKABLE bool isFeatureSupported(Feature feature) const;

    AxesOrientationMode axesOrientationMode() const;
    void setAxesOrientationMode(AxesOrientationMode axesOrientationMode);

    int currentOrientation() const;
    void setCurrentOrientation(int currentOrientation);

    int userOrientation() const;
    void setUserOrientation(int userOrientation);

    int maxBufferSize() const;
    void setMaxBufferSize(int maxBufferSize);

    int efficientBufferSize() const;
    void setEfficientBufferSize(int efficientBufferSize);

    int bufferSize() const;
    void setBufferSize(int bufferSize);

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();
    void alwaysOnChanged();
    void dataRateChanged();
    void skipDuplicatesChanged(bool skipDuplicates);
    void axesOrientationModeChanged(AxesOrientationMode axesOrientationMode);
    void currentOrientationChanged(int currentOrientation);
    void userOrientationChanged(int userOrientation);
    void maxBufferSizeChanged(int maxBufferSize);
    void efficientBufferSizeChanged(int efficientBufferSize);
    void bufferSizeChanged(int bufferSize);
    void identifierChanged();

protected:
    explicit QSensor(const QByteArray &type, QSensorPrivate &dd, QObject* parent = nullptr);
    QSensorBackend *backend() const;

private:
    void registerInstance();

    Q_DISABLE_COPY(QSensor)
    Q_DECLARE_PRIVATE(QSensor)
};

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

class Q_SENSORS_EXPORT QSensorReading : public QObject
{
    friend class QSensorBackend;

    Q_OBJECT
    Q_PROPERTY(quint64 timestamp READ timestamp)
public:
    virtual ~QSensorReading();

    quint64 timestamp() const;
    void setTimestamp(quint64 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 = nullptr);\
        virtual ~classname();\
        void copyValuesFrom(QSensorReading *other) override;\
    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, nullptr)\
        , 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);\
    }


QT_END_NAMESPACE

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

#endif
