# Copyright 2017 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Generates a list of all files in a directory.

This script takes in a directory and an output file name as input.
It then reads the directory and creates a list of all file names
in that directory.  The list is written to the output file.
There is also an option to pass in '-p' or '--pattern'
which will check each file name against a regular expression
pattern that is passed in.  Only files which match the regex
will be written to the list.
"""

import os
import re
import sys

from cStringIO import StringIO
from optparse import OptionParser

sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)),
                                "pylib"))

from mojom.generate.generator import  WriteFile


def main():
  parser = OptionParser()
  parser.add_option('-d', '--directory', help='Read files from DIRECTORY')
  parser.add_option('-o', '--output', help='Write list to FILE')
  parser.add_option('-p',
                    '--pattern',
                    help='Only reads files that name matches PATTERN',
                    default=".")
  (options, _) = parser.parse_args()
  pattern = re.compile(options.pattern)
  files = [f for f in os.listdir(options.directory) if pattern.match(f)]

  stream = StringIO()
  for f in files:
    print >> stream, f

  WriteFile(stream.getvalue(), options.output)
  stream.close()

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