#!/usr/bin/python

# Copyright (C) 2010 Jose Aliste <jose.aliste@gmail.com>
#               2011 Benjamin Kellermann <Benjamin.Kellermann@tu-dresden.de>
#
# Translated from Bash to Python by Juergen Spitzmueller <spitz@lyx.org> 2017.
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public Licence as published by the Free Software
# Foundation; either version 2 of the Licence, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public Licence for more 
# details.
#
# You should have received a copy of the GNU General Public Licence along with
# this program; if not, write to the Free Software Foundation, Inc., 51 Franklin
# Street, Fifth Floor, Boston, MA  02110-1301, USA

import sys, os.path
from subprocess import Popen

# The lyxclient command for backward search
editor_cmd = "lyxclient -g %f %l"

# Check we have (only) one argument
if len(sys.argv) != 2:
    print("Usage: evince_sync_lyx pdf_file")
    sys.exit(1)

# Arg 1 is supposed to be the PDF file
pdf_file = os.path.abspath(sys.argv[1])

# Check whether the file exists & is readable
if not os.path.isfile(pdf_file):
    print("%s is not valid/readable PDF file." % pdf_file)
    sys.exit(1)

# The accompanying synctex file has the same name than the PDF
# but with .synctex.gz extension
synctex_file, ext = os.path.splitext(pdf_file)
synctex_file += ".synctex.gz"

# If we have a synctex file, start the evince_backward_search script
SyncTeX = False
if os.path.isfile(synctex_file):
    bsproc = Popen(["evince_backward_search", pdf_file, editor_cmd])
    SyncTeX = True

# Notwithstanding the previous, start evince and open the PDF
vproc = Popen(['evince', pdf_file])
vproc.wait()

# If evince has been closed (hence vproc.wait()), we terminate
# the evince_backward_search script (if we have started it)
if SyncTeX:
    bsproc.terminate()