#!/usr/bin/python -S

"""Utility to support storing and re-using command-line arguments.

persist save [args...]
    Print a JSON-encoded set of command line arguments.  Example usage:

    persist save "$@" >$persistfile

persist run <command> [args...]
    Run a command with JSON-encoded command line arguments stored with persist
    save read from stdin.  Any arguments specified will come before persisted
    arguments. Example usage:

    persist run wifi set <$persistfile
"""

import json
import os
import sys


def main():
  if not sys.argv[1:] or sys.argv[1] not in ['save', 'run']:
    print __doc__
    sys.exit(1)
  elif sys.argv[1] == 'save':
    print json.dumps(sys.argv[2:])
  else:
    os.execvp(sys.argv[2], sys.argv[2:] + json.loads(sys.stdin.read()))


if __name__ == '__main__':
  main()