#!/usr/bin/env python3
#
# Copyright (C) 2019-2023 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/>.

import os
import unittest
import tempfile
import random
import string

from base_vyostest_shim import VyOSUnitTestSHIM

from vyos.configsession import ConfigSessionError
from vyos.utils.process import cmd
from vyos.utils.process import process_running

DDCLIENT_SYSTEMD_UNIT = '/run/systemd/system/ddclient.service.d/override.conf'
DDCLIENT_CONF = '/run/ddclient/ddclient.conf'
DDCLIENT_PID = '/run/ddclient/ddclient.pid'
DDCLIENT_PNAME = 'ddclient'

base_path = ['service', 'dns', 'dynamic']
name_path = base_path + ['name']
server = 'ddns.vyos.io'
hostname = 'test.ddns.vyos.io'
zone = 'vyos.io'
username = 'vyos_user'
password = 'paSS_@4ord'
ttl = '300'
interface = 'eth0'

class TestServiceDDNS(VyOSUnitTestSHIM.TestCase):
    def setUp(self):
        # Always start with a clean CLI instance
        self.cli_delete(base_path)

    def tearDown(self):
        # Check for running process
        self.assertTrue(process_running(DDCLIENT_PID))

        # Delete DDNS configuration
        self.cli_delete(base_path)
        self.cli_commit()

        # PID file must no londer exist after process exited
        self.assertFalse(os.path.exists(DDCLIENT_PID))

    # IPv4 standard DDNS service configuration
    def test_01_dyndns_service_standard(self):
        services = {'cloudflare': {'protocol': 'cloudflare'},
                    'freedns': {'protocol': 'freedns', 'username': username},
                    'zoneedit': {'protocol': 'zoneedit1', 'username': username}}

        for svc, details in services.items():
            self.cli_set(name_path + [svc, 'address', interface])
            self.cli_set(name_path + [svc, 'host-name', hostname])
            self.cli_set(name_path + [svc, 'password', password])
            self.cli_set(name_path + [svc, 'zone', zone])
            self.cli_set(name_path + [svc, 'ttl', ttl])
            for opt, value in details.items():
                self.cli_set(name_path + [svc, opt, value])

            # 'zone' option is supported and required by 'cloudfare', but not 'freedns' and 'zoneedit'
            self.cli_set(name_path + [svc, 'zone', zone])
            if details['protocol'] == 'cloudflare':
                pass
            else:
                # exception is raised for unsupported ones
                with self.assertRaises(ConfigSessionError):
                    self.cli_commit()
                self.cli_delete(name_path + [svc, 'zone'])

            # 'ttl' option is supported by 'cloudfare', but not 'freedns' and 'zoneedit'
            self.cli_set(name_path + [svc, 'ttl', ttl])
            if details['protocol'] == 'cloudflare':
                pass
            else:
                # exception is raised for unsupported ones
                with self.assertRaises(ConfigSessionError):
                    self.cli_commit()
                self.cli_delete(name_path + [svc, 'ttl'])

            # commit changes
            self.cli_commit()

            # Check the generating config parameters
            ddclient_conf = cmd(f'sudo cat {DDCLIENT_CONF}')
            # default value 300 seconds
            self.assertIn(f'daemon=300', ddclient_conf)
            self.assertIn(f'usev4=ifv4', ddclient_conf)
            self.assertIn(f'ifv4={interface}', ddclient_conf)
            self.assertIn(f'password=\'{password}\'', ddclient_conf)

            for opt in details.keys():
                if opt == 'username':
                    login = details[opt]
                    self.assertIn(f'login={login}', ddclient_conf)
                else:
                    tmp = details[opt]
                    self.assertIn(f'{opt}={tmp}', ddclient_conf)

    # IPv6 only DDNS service configuration
    def test_02_dyndns_service_ipv6(self):
        interval = '60'
        svc_path = name_path + ['dynv6']
        proto = 'dyndns2'
        ip_version = 'ipv6'
        wait_time = '600'
        expiry_time_good = '3600'
        expiry_time_bad = '360'

        self.cli_set(base_path + ['interval', interval])
        self.cli_set(svc_path + ['address', interface])
        self.cli_set(svc_path + ['ip-version', ip_version])
        self.cli_set(svc_path + ['protocol', proto])
        self.cli_set(svc_path + ['server', server])
        self.cli_set(svc_path + ['username', username])
        self.cli_set(svc_path + ['password', password])
        self.cli_set(svc_path + ['host-name', hostname])
        self.cli_set(svc_path + ['wait-time', wait_time])

        # expiry-time must be greater than wait-time, exception is raised otherwise
        with self.assertRaises(ConfigSessionError):
            self.cli_set(svc_path + ['expiry-time', expiry_time_bad])
            self.cli_commit()
        self.cli_set(svc_path + ['expiry-time', expiry_time_good])

        # commit changes
        self.cli_commit()

        # Check the generating config parameters
        ddclient_conf = cmd(f'sudo cat {DDCLIENT_CONF}')
        self.assertIn(f'daemon={interval}', ddclient_conf)
        self.assertIn(f'usev6=ifv6', ddclient_conf)
        self.assertIn(f'ifv6={interface}', ddclient_conf)
        self.assertIn(f'protocol={proto}', ddclient_conf)
        self.assertIn(f'server={server}', ddclient_conf)
        self.assertIn(f'login={username}', ddclient_conf)
        self.assertIn(f'password=\'{password}\'', ddclient_conf)
        self.assertIn(f'min-interval={wait_time}', ddclient_conf)
        self.assertIn(f'max-interval={expiry_time_good}', ddclient_conf)

    # IPv4+IPv6 dual DDNS service configuration
    def test_03_dyndns_service_dual_stack(self):
        services = {'cloudflare': {'protocol': 'cloudflare', 'zone': zone},
                    'freedns': {'protocol': 'freedns', 'username': username},
                    'google': {'protocol': 'googledomains', 'username': username}}
        ip_version = 'both'

        for name, details in services.items():
            self.cli_set(name_path + [name, 'address', interface])
            self.cli_set(name_path + [name, 'host-name', hostname])
            self.cli_set(name_path + [name, 'password', password])
            for opt, value in details.items():
                self.cli_set(name_path + [name, opt, value])

            # Dual stack is supported by 'cloudfare' and 'freedns' but not 'googledomains'
            # exception is raised for unsupported ones
            self.cli_set(name_path + [name, 'ip-version', ip_version])
            if details['protocol'] not in ['cloudflare', 'freedns']:
                with self.assertRaises(ConfigSessionError):
                    self.cli_commit()
                self.cli_delete(name_path + [name, 'ip-version'])

            # commit changes
            self.cli_commit()

            # Check the generating config parameters
            ddclient_conf = cmd(f'sudo cat {DDCLIENT_CONF}')
            if details['protocol'] not in ['cloudflare', 'freedns']:
                self.assertIn(f'usev4=ifv4', ddclient_conf)
                self.assertIn(f'ifv4={interface}', ddclient_conf)
            else:
                self.assertIn(f'usev4=ifv4', ddclient_conf)
                self.assertIn(f'usev6=ifv6', ddclient_conf)
                self.assertIn(f'ifv4={interface}', ddclient_conf)
                self.assertIn(f'ifv6={interface}', ddclient_conf)
            self.assertIn(f'password=\'{password}\'', ddclient_conf)

            for opt in details.keys():
                if opt == 'username':
                    login = details[opt]
                    self.assertIn(f'login={login}', ddclient_conf)
                else:
                    tmp = details[opt]
                    self.assertIn(f'{opt}={tmp}', ddclient_conf)

    def test_04_dyndns_rfc2136(self):
        # Check if DDNS service can be configured and runs
        svc_path = name_path + ['vyos']
        proto = 'nsupdate'

        with tempfile.NamedTemporaryFile(prefix='/config/auth/') as key_file:
            key_file.write(b'S3cretKey')

            self.cli_set(svc_path + ['address', interface])
            self.cli_set(svc_path + ['protocol', proto])
            self.cli_set(svc_path + ['server', server])
            self.cli_set(svc_path + ['zone', zone])
            self.cli_set(svc_path + ['key', key_file.name])
            self.cli_set(svc_path + ['ttl', ttl])
            self.cli_set(svc_path + ['host-name', hostname])

            # commit changes
            self.cli_commit()

            # Check some generating config parameters
            ddclient_conf = cmd(f'sudo cat {DDCLIENT_CONF}')
            self.assertIn(f'use=if', ddclient_conf)
            self.assertIn(f'if={interface}', ddclient_conf)
            self.assertIn(f'protocol={proto}', ddclient_conf)
            self.assertIn(f'server={server}', ddclient_conf)
            self.assertIn(f'zone={zone}', ddclient_conf)
            self.assertIn(f'password=\'{key_file.name}\'', ddclient_conf)
            self.assertIn(f'ttl={ttl}', ddclient_conf)

    def test_05_dyndns_hostname(self):
        # Check if DDNS service can be configured and runs
        svc_path = name_path + ['namecheap']
        proto = 'namecheap'
        hostnames = ['@', 'www', hostname, f'@.{hostname}']

        for name in hostnames:
            self.cli_set(svc_path + ['address', interface])
            self.cli_set(svc_path + ['protocol', proto])
            self.cli_set(svc_path + ['server', server])
            self.cli_set(svc_path + ['username', username])
            self.cli_set(svc_path + ['password', password])
            self.cli_set(svc_path + ['host-name', name])

            # commit changes
            self.cli_commit()

            # Check the generating config parameters
            ddclient_conf = cmd(f'sudo cat {DDCLIENT_CONF}')
            self.assertIn(f'protocol={proto}', ddclient_conf)
            self.assertIn(f'server={server}', ddclient_conf)
            self.assertIn(f'login={username}', ddclient_conf)
            self.assertIn(f'password=\'{password}\'', ddclient_conf)
            self.assertIn(f'{name}', ddclient_conf)

    def test_06_dyndns_web_options(self):
        # Check if DDNS service can be configured and runs
        svc_path = name_path + ['cloudflare']
        proto = 'cloudflare'
        web_url_good = 'https://ifconfig.me/ip'
        web_url_bad = 'http:/ifconfig.me/ip'

        self.cli_set(svc_path + ['protocol', proto])
        self.cli_set(svc_path + ['zone', zone])
        self.cli_set(svc_path + ['password', password])
        self.cli_set(svc_path + ['host-name', hostname])
        self.cli_set(svc_path + ['web-options', 'url', web_url_good])

        # web-options is supported only with web service based address lookup
        # exception is raised for interface based address lookup
        with self.assertRaises(ConfigSessionError):
            self.cli_set(svc_path + ['address', interface])
            self.cli_commit()
        self.cli_set(svc_path + ['address', 'web'])

        # commit changes
        self.cli_commit()

        # web-options must be a valid URL
        with self.assertRaises(ConfigSessionError):
            self.cli_set(svc_path + ['web-options', 'url', web_url_bad])
            self.cli_commit()
        self.cli_set(svc_path + ['web-options', 'url', web_url_good])

        # commit changes
        self.cli_commit()

        # Check the generating config parameters
        ddclient_conf = cmd(f'sudo cat {DDCLIENT_CONF}')
        self.assertIn(f'usev4=webv4', ddclient_conf)
        self.assertIn(f'webv4={web_url_good}', ddclient_conf)
        self.assertIn(f'protocol={proto}', ddclient_conf)
        self.assertIn(f'zone={zone}', ddclient_conf)
        self.assertIn(f'password=\'{password}\'', ddclient_conf)
        self.assertIn(f'{hostname}', ddclient_conf)

    def test_07_dyndns_vrf(self):
        # Table number randomized, but should be within range 100-65535
        vrf_table = "".join(random.choices(string.digits, k=4))
        vrf_name = f'vyos-test-{vrf_table}'
        svc_path = name_path + ['cloudflare']
        proto = 'cloudflare'

        self.cli_set(['vrf', 'name', vrf_name, 'table', vrf_table])
        self.cli_set(base_path + ['vrf', vrf_name])

        self.cli_set(svc_path + ['address', interface])
        self.cli_set(svc_path + ['protocol', proto])
        self.cli_set(svc_path + ['host-name', hostname])
        self.cli_set(svc_path + ['zone', zone])
        self.cli_set(svc_path + ['password', password])

        # commit changes
        self.cli_commit()

        # Check for process in VRF
        systemd_override = cmd(f'cat {DDCLIENT_SYSTEMD_UNIT}')
        self.assertIn(f'ExecStart=ip vrf exec {vrf_name} /usr/bin/ddclient -file {DDCLIENT_CONF}',
                      systemd_override)

        # Check for process in VRF
        proc = cmd(f'ip vrf pids {vrf_name}')
        self.assertIn(DDCLIENT_PNAME, proc)

        # Cleanup VRF
        self.cli_delete(['vrf', 'name', vrf_name])

if __name__ == '__main__':
    unittest.main(verbosity=2)