#!/usr/bin/env python
"""Convert surface to BEM FIF file

Example usage

mne surf2bem --surf ${SUBJECTS_DIR}/${SUBJECT}/surf/lh.seghead --fif \
${SUBJECTS_DIR}/${SUBJECT}/bem/${SUBJECT}-head.fif --id=4

"""
from __future__ import print_function
# Authors: Alexandre Gramfort <alexandre.gramfort@telecom-paristech.fr>
#
# License: BSD (3-clause)

import sys

import mne

if __name__ == '__main__':

    from mne.commands.utils import get_optparser

    parser = get_optparser(__file__)

    parser.add_option("-s", "--surf", dest="surf",
                    help="Surface in Freesurfer format", metavar="FILE")
    parser.add_option("-f", "--fif", dest="fif",
                    help="FIF file produced", metavar="FILE")
    parser.add_option("-i", "--id", dest="id", default=4,
                    help=("Surface Id (e.g. 4 sur head surface)"))

    options, args = parser.parse_args()

    if options.surf is None:
        parser.print_help()
        sys.exit(1)

    print("Converting %s to BEM FIF file." % options.surf)

    points, tris = mne.read_surface(options.surf)
    points *= 1e-3
    surf = dict(coord_frame=5, id=int(options.id), nn=None, np=len(points),
                ntri=len(tris), rr=points, sigma=1, tris=tris)
    mne.write_bem_surface(options.fif, surf)