# Copyright (C) 2018-2020 2ndQuadrant Limited
#
# This file is part of Barman.
#
# Barman is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Barman is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Barman.  If not, see <http://www.gnu.org/licenses/>.

import json
import logging
from contextlib import closing

import barman
from barman.cloud import CloudInterface, S3BackupCatalog, configure_logging
from barman.infofile import BackupInfo
from barman.utils import force_str

try:
    import argparse
except ImportError:
    raise SystemExit("Missing required python module: argparse")


def main(args=None):
    """
    The main script entry point

    :param list[str] args: the raw arguments list. When not provided
        it defaults to sys.args[1:]
    """
    config = parse_arguments(args)
    configure_logging(config)

    try:
        cloud_interface = CloudInterface(
            url=config.source_url,
            encryption=config.encryption,
            profile_name=config.profile,
            endpoint_url=config.endpoint_url)

        with closing(cloud_interface):
            catalog = S3BackupCatalog(
                cloud_interface=cloud_interface,
                server_name=config.server_name)

            if not cloud_interface.test_connectivity():
                raise SystemExit(1)
            # If test is requested, just exit after connectivity test
            elif config.test:
                raise SystemExit(0)

            if not cloud_interface.bucket_exists:
                logging.error("Bucket %s does not exist",
                              cloud_interface.bucket_name)
                raise SystemExit(1)

            backup_list = catalog.get_backup_list()

            # Output
            if config.format == 'console':
                COLUMNS = "{:<20}{:<25}{:<30}"
                print(COLUMNS.format("Backup ID", "End Time", "Begin Wal"))
                for backup_id in sorted(backup_list):
                    item = backup_list[backup_id]
                    if item and item.status == BackupInfo.DONE:
                        print(COLUMNS.format(
                            item.backup_id,
                            item.end_time.strftime("%Y-%m-%d %H:%M:%S"),
                            item.begin_wal
                        ))
            else:
                print(json.dumps({"backups_list": [
                    backup_list[backup_id].to_json()
                    for backup_id in sorted(backup_list)]}))

    except Exception as exc:
        logging.error("Barman cloud backup list exception: %s",
                      force_str(exc))
        logging.debug('Exception details:', exc_info=exc)
        raise SystemExit(1)


def parse_arguments(args=None):
    """
    Parse command line arguments

    :return: The options parsed
    """

    parser = argparse.ArgumentParser(
        description='This script can be used to list backups '
                    'made with barman-cloud-backup command. '
                    'Currently only AWS S3 is supported.',
        add_help=False
    )

    parser.add_argument(
        'source_url',
        help='URL of the cloud source, such as a bucket in AWS S3.'
             ' For example: `s3://bucket/path/to/folder`.'
    )
    parser.add_argument(
        'server_name',
        help='the name of the server as configured in Barman.'
    )
    parser.add_argument(
        '-V', '--version',
        action='version', version='%%(prog)s %s' % barman.__version__
    )
    parser.add_argument(
        '--help',
        action='help',
        help='show this help message and exit')
    verbosity = parser.add_mutually_exclusive_group()
    verbosity.add_argument(
        '-v', '--verbose',
        action='count',
        default=0,
        help='increase output verbosity (e.g., -vv is more than -v)')
    verbosity.add_argument(
        '-q', '--quiet',
        action='count',
        default=0,
        help='decrease output verbosity (e.g., -qq is less than -q)')
    parser.add_argument(
        '-P', '--profile',
        help='profile name (e.g. INI section in AWS credentials file)',
    )
    parser.add_argument(
        "-e", "--encryption",
        help="Enable server-side encryption for the transfer. "
             "Allowed values: 'AES256', 'aws:kms'",
        choices=['AES256', 'aws:kms'],
        metavar="ENCRYPTION",
    )
    parser.add_argument(
        "-t", "--test",
        help="Test cloud connectivity and exit",
        action="store_true",
        default=False
    )
    parser.add_argument(
        "--format",
        default="console",
        help="Output format (console or json). Default console."
    )
    parser.add_argument(
        "--endpoint-url",
        help="Override default S3 endpoint URL with the given one",
    )
    return parser.parse_args(args=args)


if __name__ == '__main__':
    main()
