#
# Copyright 2005-2019 ECMWF.
#
# This software is licensed under the terms of the Apache Licence Version 2.0
# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
#
# In applying this licence, ECMWF does not waive the privileges and immunities
# granted to it by virtue of its status as an intergovernmental organisation
# nor does it submit to any jurisdiction.
#

import traceback
import sys

from eccodes import *

VERBOSE = 1  # verbose error reporting


def example():
    """
    Encoding of the pv coefficients.
    """
    # read the coefficients from file
    pv = []
    for line in open('../../data/60_model_levels'):
        pv.extend([float(x) for x in line.strip().split('\t')])

    numberOfLevels = 60
    numberOfCoefficients = 2 * (numberOfLevels + 1)
    assert (len(pv) == numberOfCoefficients)

    fout = open('grib_set_pv.py.temp.grib', 'wb')
    gid = codes_grib_new_from_samples('reduced_gg_sfc_grib1')

    codes_set(gid, 'typeOfLevel', 'hybrid')
    codes_set(gid, 'level', 2)
    codes_set(gid, 'PVPresent', 1)
    codes_set_array(gid, 'pv', pv)

    codes_write(gid, fout)

    codes_release(gid)
    fout.close()


def main():
    try:
        example()
    except CodesInternalError as err:
        if VERBOSE:
            traceback.print_exc(file=sys.stderr)
        else:
            sys.stderr.write(err.msg + '\n')

        return 1


if __name__ == '__main__':
    sys.exit(main())