#!/usr/bin/env python3
# Copyright 2013 The Flutter Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

'''Reads the contents of a kernel manifest generated by the build and
  converts it to a format suitable for distribution_entries
'''

import argparse
import collections
import json
import os
import sys

Entry = collections.namedtuple('Entry', ['source', 'dest'])


def collect(path_prefix, lines):
  '''Reads the kernel manifest and creates an array of Entry objects.
    - lines: a list of lines from the manifest
    '''
  entries = []
  for line in lines:
    values = line.split("=", 1)
    entries.append(Entry(source=path_prefix + values[1], dest=values[0]))

  return entries


def main():
  parser = argparse.ArgumentParser(description=__doc__)
  parser.add_argument(
      '--path_prefix',
      help='Directory path containing the manifest entry sources',
      required=True
  )
  parser.add_argument(
      '--input', help='Path to original manifest', required=True
  )
  parser.add_argument(
      '--output', help='Path to the updated json file', required=True
  )
  args = parser.parse_args()

  with open(args.input, 'r') as input_file:
    contents = input_file.read().splitlines()

  entries = collect(args.path_prefix, contents)

  if entries is None:
    return 1

  with open(args.output, 'w') as output_file:
    json.dump([e._asdict() for e in entries],
              output_file,
              indent=2,
              sort_keys=True,
              separators=(',', ': '))

  return 0


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