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#ifdef HAVE_NUMPY
// Include numpy first to get the proper PyArray_Check
#  include <numpy/arrayobject.h>
#  include "pyside_numpy.h"
#  include <QtCore/QDebug>

// Convert X,Y of type T data to a list of points (QPoint, PointF)
template <class T, class Point>
static QList<Point>
    xyDataToQPointHelper(const void *xData, const void *yData, qsizetype size)
{
    auto *x = reinterpret_cast<const T *>(xData);
    auto *y = reinterpret_cast<const T *>(yData);
    QList<Point> result;
    result.reserve(size);
    for (auto xEnd = x + size; x < xEnd; ++x, ++y)
        result.append(Point(*x, *y));
    return result;
}

// Convert X,Y of double/float type data to a list of QPoint (rounding)
template <class T>
static QList<QPoint>
    xyFloatDataToQPointHelper(const void *xData, const void *yData, qsizetype size)
{
    auto *x = reinterpret_cast<const T *>(xData);
    auto *y = reinterpret_cast<const T *>(yData);
    QList<QPoint> result;
    result.reserve(size);
    for (auto xEnd = x + size; x < xEnd; ++x, ++y)
        result.append(QPoint(qRound(*x), qRound(*y)));
    return result;
}


namespace PySide::Numpy
{

bool init()
{
    import_array1(false);
    return true;
}

bool check(PyObject *pyIn)
{
    return PyArray_Check(pyIn);
}

View View::fromPyObject(PyObject *pyIn)
{
    if (pyIn == nullptr || PyArray_Check(pyIn) == 0)
        return {};
    auto *ar = reinterpret_cast<PyArrayObject *>(pyIn);
    if ((PyArray_FLAGS(ar) & NPY_ARRAY_C_CONTIGUOUS) == 0)
        return {};
    const int ndim = PyArray_NDIM(ar);
    if (ndim > 2)
        return {};

    View::Type type;
    switch (PyArray_TYPE(ar)) {
    case NPY_INT:
        type = View::Int;
        break;
    case NPY_UINT:
        type = View::Unsigned;
        break;
    case NPY_FLOAT:
        type = View::Float;
        break;
    case NPY_DOUBLE:
        type = View::Double;
        break;
    default:
        return {};
    }

    View result;
    result.ndim = ndim;
    result.type = type;
    result.data = PyArray_DATA(ar);
    result.dimensions[0] = PyArray_DIMS(ar)[0];
    result.stride[0] = PyArray_STRIDES(ar)[0];
    if (ndim > 1) {
        result.dimensions[1] = PyArray_DIMS(ar)[1];
        result.stride[1] = PyArray_STRIDES(ar)[1];
    } else {
        result.dimensions[1] = result.stride[1] = 0;
    }
    return result;
}

QList<QPointF> xyDataToQPointFList(PyObject *pyXIn, PyObject *pyYIn)
{
    View xv = View::fromPyObject(pyXIn);
    View yv = View::fromPyObject(pyYIn);
    if (!xv.sameLayout(yv))
        return {};
    const qsizetype size = qMin(xv.dimensions[0], yv.dimensions[0]);
    if (size == 0)
        return {};
    switch (xv.type) {
    case PySide::Numpy::View::Int:
        return xyDataToQPointHelper<int, QPointF>(xv.data, yv.data, size);
    case PySide::Numpy::View::Unsigned:
        return xyDataToQPointHelper<unsigned, QPointF>(xv.data, yv.data, size);
    case PySide::Numpy::View::Float:
        return xyDataToQPointHelper<float, QPointF>(xv.data, yv.data, size);
    case PySide::Numpy::View::Double:
        break;
    }
    return xyDataToQPointHelper<double, QPointF>(xv.data, yv.data, size);
}

QList<QPoint> xyDataToQPointList(PyObject *pyXIn, PyObject *pyYIn)
{
    View xv = View::fromPyObject(pyXIn);
    View yv = View::fromPyObject(pyYIn);
    if (!xv.sameLayout(yv))
        return {};
    const qsizetype size = qMin(xv.dimensions[0], yv.dimensions[0]);
    if (size == 0)
        return {};
    switch (xv.type) {
    case PySide::Numpy::View::Int:
        return xyDataToQPointHelper<int, QPoint>(xv.data, yv.data, size);
    case PySide::Numpy::View::Unsigned:
        return xyDataToQPointHelper<unsigned, QPoint>(xv.data, yv.data, size);
    case PySide::Numpy::View::Float:
        return xyFloatDataToQPointHelper<float>(xv.data, yv.data, size);
    case PySide::Numpy::View::Double:
        break;
    }
    return xyFloatDataToQPointHelper<double>(xv.data, yv.data, size);
}

template <class T>
static void debugArray(QDebug debug, const  T *data, int n)
{
    static const int maxData = 10;
    debug << " = ";
    auto *end = data + qMin(n, maxData);
    for (auto *d = data; d != end; ++d) {
        if (d != data)
            debug << ", ";
        debug << *d;
    }
    if (n > maxData)
        debug << "...";
}

QDebug operator<<(QDebug debug, const debugPyArrayObject &a)
{
    QDebugStateSaver saver(debug);
    debug.noquote();
    debug.nospace();

    debug << "PyArrayObject(";
    if (a.m_object == nullptr) {
        debug << '0';
    } else if (PyArray_Check(a.m_object) != 0) {
        auto *ar = reinterpret_cast<PyArrayObject *>(a.m_object);
        const int ndim = PyArray_NDIM(ar);
        const int type = PyArray_TYPE(ar);
        const int flags  = PyArray_FLAGS(ar);
        debug << "ndim=" << ndim << " [";
        for (int d = 0; d < ndim; ++d) {
            if (d)
                debug << ", ";
            debug << PyArray_DIMS(ar)[d];
        }
        debug << "], type=";
        switch (type) {
        case NPY_INT:
            debug << "int";
            break;
        case NPY_UINT:
            debug << "uint";
            break;
        case NPY_FLOAT:
            debug << "float";
            break;
        case NPY_DOUBLE:
            debug << "double";
            break;
        default:
            debug << '(' << type << ')';
            break;
        }
        debug << ", flags=0x" << Qt::hex << flags << Qt::dec;
        if ((flags & NPY_ARRAY_C_CONTIGUOUS) != 0)
            debug << " [C-contiguous]";
        if ((flags & NPY_ARRAY_F_CONTIGUOUS) != 0)
            debug << " [Fortran-contiguous]";
        if ((flags & NPY_ARRAY_ALIGNED) != 0)
                debug << " [aligned]";
        if ((flags & NPY_ARRAY_OWNDATA) != 0)
                debug << " [owndata]";
        if ((flags & NPY_ARRAY_WRITEABLE) != 0)
            debug << " [writeable]";

        if (const int dim0 = PyArray_DIMS(ar)[0]) {
            auto *data = PyArray_DATA(ar);
            switch (type) {
            case NPY_INT:
                debugArray(debug, reinterpret_cast<const int *>(data), dim0);
                break;
            case NPY_UINT:
                debugArray(debug, reinterpret_cast<const unsigned *>(data), dim0);
                break;
            case NPY_FLOAT:
                debugArray(debug, reinterpret_cast<const float *>(data), dim0);
                break;
            case NPY_DOUBLE:
                debugArray(debug, reinterpret_cast<const double *>(data), dim0);
                break;
            }
        }
    } else {
        debug << "Invalid";
    }
    debug << ')';
    return debug;
}

} //namespace PySide::Numpy

#else // HAVE_NUMPY
#  include "pyside_numpy.h"
#  include <QtCore/QDebug>
namespace PySide::Numpy
{

bool init()
{
    return true;
}

bool check(PyObject *)
{
    return false;
}

View View::fromPyObject(PyObject *)
{
    return {};
}

QList<QPointF> xyDataToQPointFList(PyObject *, PyObject *)
{
    qWarning("Unimplemented function %s, (numpy was not found).", __FUNCTION__);
    return {};
}

QList<QPoint> xyDataToQPointList(PyObject *, PyObject *)
{
    qWarning("Unimplemented function %s, (numpy was not found).", __FUNCTION__);
    return {};
}

QDebug operator<<(QDebug debug, const debugPyArrayObject &)
{
    debug << "Unimplemented function " <<  __FUNCTION__ << ", (numpy was not found).";
    return debug;
}

} //namespace PySide::Numpy

#endif // !HAVE_NUMPY

namespace PySide::Numpy
{

bool View::sameLayout(const View &rhs) const
{
    return rhs && *this && ndim == rhs.ndim && type == rhs.type;
}

bool View::sameSize(const View &rhs) const
{
    return sameLayout(rhs)
        && dimensions[0] == rhs.dimensions[0] && dimensions[1] == rhs.dimensions[1];
}

QDebug operator<<(QDebug debug, const View &v)
{
    QDebugStateSaver saver(debug);
    debug.noquote();
    debug.nospace();

    debug << "PySide::Numpy::View(";
    if (v) {
        debug << "type=" << v.type << ", ndim=" << v.ndim << " ["
            << v.dimensions[0];
        if (v.ndim > 1)
           debug << ", " << v.dimensions[1];
        debug << "], stride=[" << v.stride[0];
        if (v.ndim > 1)
           debug << ", " << v.stride[1];
        debug << "], data=" << v.data;
    } else {
        debug << "invalid";
    }
    debug << ')';
    return debug;
}

} //namespace PySide::Numpy