#!/usr/bin/env python
"""
Writes a simple NeXus HDF5 file using h5py with links
according to the example from Figure 2.1 in the Design chapter
"""

from pathlib import Path

import numpy
from nexusformat.nexus import NXdata
from nexusformat.nexus import NXdetector
from nexusformat.nexus import NXentry
from nexusformat.nexus import NXfield
from nexusformat.nexus import NXinstrument
from nexusformat.nexus import NXlink
from nexusformat.nexus import nxopen

filename = str(Path(__file__).absolute().parent.parent / "simple_example.dat")
buffer = numpy.loadtxt(filename).T
tthData = buffer[0]  # float[]
countsData = numpy.asarray(buffer[1], "int32")  # int[]

with nxopen("simple_example_write2.hdf5", "w") as f:  # create the HDF5 NeXus file
    f["entry"] = NXentry()
    f["entry/instrument"] = NXinstrument()
    f["entry/instrument/detector"] = NXdetector()

    # store the data in the NXdetector group
    f["entry/instrument/detector/two_theta"] = NXfield(tthData, units="degrees")
    f["entry/instrument/detector/counts"] = NXfield(countsData, units="counts")

    f["entry/data"] = NXdata(
        NXlink("/entry/instrument/detector/counts"),
        NXlink("/entry/instrument/detector/two_theta"),
    )
    f["entry/data"].set_default()