#!/usr/bin/env python
#
# This file is part of Harvesting Kit.
# Copyright (C) 2014 CERN.
#
# Harvesting Kit is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.
#
# Harvesting Kit 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 License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Harvesting Kit; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.

# taken from http://stackoverflow.com/a/8898439

import os
import sys
import codecs

BUFSIZE = 4096
BOMLEN = len(codecs.BOM_UTF8)

for path in sys.argv[1:]:
    with open(path, "r+b") as fp:
        print >> sys.stderr, "Stripping BOM from %s" % path
        chunk = fp.read(BUFSIZE)
        if chunk.startswith(codecs.BOM_UTF8):
            i = 0
            chunk = chunk[BOMLEN:]
            while chunk:
                fp.seek(i)
                fp.write(chunk)
                i += len(chunk)
                fp.seek(BOMLEN, os.SEEK_CUR)
                chunk = fp.read(BUFSIZE)
            fp.seek(-BOMLEN, os.SEEK_CUR)
            fp.truncate()

