#!/usr/bin/env python3
#
# Copyright (C) 2021 VyOS maintainers and contributors
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 or later 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, see <http://www.gnu.org/licenses/>.

# * Migrate system signed certificate to use PKI

import sys

from vyos.configtree import ConfigTree
from vyos.pki import create_certificate
from vyos.pki import create_certificate_request
from vyos.pki import create_private_key
from vyos.pki import encode_certificate
from vyos.pki import encode_private_key

if len(sys.argv) < 2:
    print("Must specify file name!")
    sys.exit(1)

file_name = sys.argv[1]

with open(file_name, 'r') as f:
    config_file = f.read()

config = ConfigTree(config_file)

base = ['service', 'https', 'certificates']
pki_base = ['pki']

if not config.exists(base + ['system-generated-certificate']):
    sys.exit(0)

def wrapped_pem_to_config_value(pem):
    out = []
    for line in pem.strip().split("\n"):
        if not line or line.startswith("-----") or line[0] == '#':
            continue
        out.append(line)
    return "".join(out)

if not config.exists(pki_base + ['certificate']):
    config.set(pki_base + ['certificate'])
    config.set_tag(pki_base + ['certificate'])

valid_days = 365
if config.exists(base + ['system-generated-certificate', 'lifetime']):
    valid_days = int(config.return_value(base + ['system-generated-certificate', 'lifetime']))

key = create_private_key('rsa', 2048)
subject = {'country': 'GB', 'state': 'N/A', 'locality': 'N/A', 'organization': 'VyOS', 'common_name': 'vyos'}
cert_req = create_certificate_request(subject, key, ['vyos'])
cert = create_certificate(cert_req, cert_req, key, valid_days)

if cert:
    cert_pem = encode_certificate(cert)
    config.set(pki_base + ['certificate', 'generated_https', 'certificate'], value=wrapped_pem_to_config_value(cert_pem))

if key:
    key_pem = encode_private_key(key)
    config.set(pki_base + ['certificate', 'generated_https', 'private', 'key'], value=wrapped_pem_to_config_value(key_pem))

if cert and key:
    config.set(base + ['certificate'], value='generated_https')
else:
    print('Failed to migrate system-generated-certificate from https service')

config.delete(base + ['system-generated-certificate'])

try:
    with open(file_name, 'w') as f:
        f.write(config.to_string())
except OSError as e:
    print("Failed to save the modified config: {}".format(e))
    sys.exit(1)