# Copyright 2018 The Bazel Authors. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import argparse
import os
import zipfile


def _is_jar(jar):
    if not os.path.exists(jar):
        raise argparse.ArgumentTypeError("jar:{0} does not exist".format(jar))
    else:
        return zipfile.ZipFile(jar)


def _extract_root_entry(jar, entry_path, touch=False):
    """
    Extracts a root entry from a jar. and write it to a path.

    entry_path is absolute and the basename is used to extract the entry from the jar.

    :param jar: The jar from which to make the extraction.
    :param entry_path: An absolute file path to where the entry should be written.
    :param touch: Should the file be touched if it was not found in the jar.
    """
    basename = os.path.basename(entry_path)
    try:
        jar.read(basename)
    except Exception as ex:
        if touch:
            f = open(entry_path, 'a')
            f.close()
            return
        else:
            raise ex
    jar.extract(basename, path=os.path.dirname(entry_path))


def _main(p):
    args = p.parse_args()
    _extract_root_entry(args.jar, args.out)
    for e in args.aux:
        _extract_root_entry(args.jar, e, touch=True)


parser = argparse.ArgumentParser()

parser.add_argument("--jar", type=_is_jar, required=True)
parser.add_argument("--out", required=True, help="mandatory paths to files that should be extracted from the root")
parser.add_argument(
    "--aux", nargs="*",
    help="""paths to files that should be extracted from the root, if the files do not exist they are touched.""")

_main(parser)