#!/usr/bin/env python
"""
Icinga/Nagios plugin to check if pip upgrade is available

Copyright (c) 2022 Benjamin Renard <brenard@zionetrix.net>

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License version 3
as published by the Free Software Foundation.

This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
"""

import sys
import subprocess
import argparse
import json
import os
import logging
import traceback


# nagios exit code
STATUS = {
    'OK': 0,
    'WARNING': 1,
    'CRITICAL': 2,
    'UNKNOWN': 3
}

parser = argparse.ArgumentParser()
parser.add_argument(
    '-d', '--debug',
    action="store_true",
    dest="debug",
    default=False
)

parser.add_argument(
    '-b', '--bin',
    action="store",
    dest="bin",
    help="Python binary path",
    type=str
)

parser.add_argument(
    action="store",
    dest="packages",
    help=(
        "Python package(s) to check. By default, all installed"
        "packages are checked."
    ),
    nargs='*',
    default=[]
)

options = parser.parse_args()

logging.basicConfig(
    level=logging.DEBUG if options.debug else logging.INFO,
    format='%(asctime)s - %(levelname)s - %(message)s')

if options.bin and not os.path.exists(options.bin):
    print(f'UNKNOWN - python executable "{options.bin}" not found')
    sys.exit(STATUS['UNKNOWN'])

cmd = [
    options.bin if options.bin else sys.executable, '-m', 'pip', 'list',
    '--format', 'json', '--outdated'
]
logging.debug('Execute external command: %s', ' '.join(cmd))
output = subprocess.check_output(cmd)
logging.debug('Output:\n%s', output)

try:
    outdated_packages = dict(
        (package['name'], package)
        for package in json.loads(output)
        if not options.packages or package['name'] in options.packages
    )
except Exception as exc:  # pylint: disable=broad-except
    print('UNKNOWN - Exception occured parsing pip output')
    traceback.print_exc(exc)
    sys.exit(STATUS['UNKNOWN'])

if outdated_packages:
    if len(outdated_packages) > 1:
        print(f'WARNING - {len(outdated_packages)} upgrades available')
        print('\n'.join([
            f' - {name} ({p["version"]} => {p["latest_version"]})'
            for name, p in outdated_packages.items()
        ]))
    else:
        name = next(iter(outdated_packages))
        p = outdated_packages[name]
        print(
            f'WARNING - available upgrade for {name} '
            f'({p["version"]} => {p["latest_version"]})'
        )
    sys.exit(STATUS['WARNING'])

if options.packages and len(options.packages) == 1:
    print(f'OK - {options.packages[0]} is uptodate')
else:
    print('OK - all packages is uptodate')
sys.exit(STATUS['OK'])