#!/usr/bin/env python3

# Copyright 2021 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

#### CATEGORY=Other

import argparse
import json
import os
import sys
import textwrap

def parse_package_config(input, out, packages):
    with open(input, 'r') as f:
      entries = json.load(f)['packages']

    rel_to_out = os.path.relpath(os.path.dirname(input), start=os.path.dirname(out))
    for entry in entries:
        root_uri = entry['rootUri']
        rel_root_uri = os.path.join(rel_to_out, root_uri)
        entry['rootUri'] = rel_root_uri
        packages.append(entry)

def main():
    parser = argparse.ArgumentParser(
        description=(textwrap.dedent('''\
            Combines two package_config.json files and outputs them as one.
        ''')),
        formatter_class=argparse.RawDescriptionHelpFormatter,
    )
    parser.add_argument('--first',
                        help='The path to the first package_config.json file',
                        required=True)
    parser.add_argument('--second',
                        help='The path to the second package_config.json file',
                        required=True)
    parser.add_argument('--out',
                        help='The path to the output file',
                        required=True)
    args = parser.parse_args()

    packages = []
    parse_package_config(args.first, args.out, packages)
    parse_package_config(args.second, args.out, packages)

    package_config = {
        'configVersion': 2,
        'packages': packages,
        'generator': os.path.basename(__file__)
    }

    with open(args.out, 'w') as package_config_json:
          package_config_json.write(json.dumps(package_config, sort_keys=True, indent=2))

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