#! /usr/bin/python3
# -*- coding: utf-8 -*-

from __future__ import print_function

import sys
import json
import jsonpatch
import argparse


parser = argparse.ArgumentParser(description='Diff two JSON files')
parser.add_argument('FILE1', type=argparse.FileType('r'))
parser.add_argument('FILE2', type=argparse.FileType('r'))
parser.add_argument('--indent', type=int, default=None,
                    help='Indent output by n spaces')
parser.add_argument('-v', '--version', action='version',
                    version='%(prog)s ' + jsonpatch.__version__)


def main():
    try:
        diff_files()
    except KeyboardInterrupt:
        sys.exit(1)


def diff_files():
    """ Diffs two JSON files and prints a patch """
    args = parser.parse_args()
    doc1 = json.load(args.FILE1)
    doc2 = json.load(args.FILE2)
    patch = jsonpatch.make_patch(doc1, doc2)
    if patch.patch:
        print(json.dumps(patch.patch, indent=args.indent))
        sys.exit(1)

if __name__ == "__main__":
    main()