#!/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/>.

import os
import unittest

from vyos.configsession import ConfigSession
from vyos.configsession import ConfigSessionError
from vyos.util import cmd
from vyos.util import process_named_running

PROCESS_NAME = 'bfdd'
base_path = ['protocols', 'bfd']

dum_if = 'dum1001'
neighbor_config = {
    '192.0.2.10' : {
        'intv_rx'    : '500',
        'intv_tx'    : '600',
        'multihop'   : '',
        'source_addr': '192.0.2.254',
        },
    '192.0.2.20' : {
        'echo_mode'  : '',
        'intv_echo'  : '100',
        'intv_mult'  : '111',
        'intv_rx'    : '222',
        'intv_tx'    : '333',
        'shutdown'   : '',
        'source_intf': dum_if,
        },
    '2001:db8::a' : {
        'source_addr': '2001:db8::1',
        'source_intf': dum_if,
        },
    '2001:db8::b' : {
        'source_addr': '2001:db8::1',
        'multihop'   : '',
        },
}

def getFRRconfig():
    return cmd('vtysh -c "show run" | sed -n "/^bfd/,/^!/p"')

def getBFDPeerconfig(peer):
    return cmd(f'vtysh -c "show run" | sed -n "/^ {peer}/,/^!/p"')

class TestProtocolsBFD(unittest.TestCase):
    def setUp(self):
        self.session = ConfigSession(os.getpid())
        self.session.set(['interfaces', 'dummy', dum_if, 'address', '192.0.2.1/24'])
        self.session.set(['interfaces', 'dummy', dum_if, 'address', '2001:db8::1/64'])

    def tearDown(self):
        self.session.delete(['interfaces', 'dummy', dum_if])
        self.session.delete(base_path)
        self.session.commit()
        del self.session

        # Check for running process
        self.assertTrue(process_named_running(PROCESS_NAME))

    def test_bfd_simple(self):
        for peer, peer_config in neighbor_config.items():
            if 'echo_mode' in peer_config:
                self.session.set(base_path + ['peer', peer, 'echo-mode'])
            if 'intv_echo' in peer_config:
                self.session.set(base_path + ['peer', peer, 'interval', 'echo-interval', peer_config["intv_echo"]])
            if 'intv_mult' in peer_config:
                self.session.set(base_path + ['peer', peer, 'interval', 'multiplier', peer_config["intv_mult"]])
            if 'intv_rx' in peer_config:
                self.session.set(base_path + ['peer', peer, 'interval', 'receive', peer_config["intv_rx"]])
            if 'intv_tx' in peer_config:
                self.session.set(base_path + ['peer', peer, 'interval', 'transmit', peer_config["intv_tx"]])
            if 'multihop' in peer_config:
                self.session.set(base_path + ['peer', peer, 'multihop'])
            if 'shutdown' in peer_config:
                self.session.set(base_path + ['peer', peer, 'shutdown'])
            if 'source_addr' in peer_config:
                self.session.set(base_path + ['peer', peer, 'source', 'address', peer_config["source_addr"]])
            if 'source_intf' in peer_config:
                self.session.set(base_path + ['peer', peer, 'source', 'interface', peer_config["source_intf"]])

        # commit changes
        self.session.commit()

        # Verify FRR bgpd configuration
        frrconfig = getFRRconfig()
        for peer, peer_config in neighbor_config.items():
            tmp = f'peer {peer}'
            if 'multihop' in peer_config:
                tmp += f' multihop'
            if 'source_addr' in peer_config:
                tmp += f' local-address {peer_config["source_addr"]}'
            if 'source_intf' in peer_config:
                tmp += f' interface {peer_config["source_intf"]}'

            self.assertIn(tmp, frrconfig)
            peerconfig = getBFDPeerconfig(tmp)

            if 'echo_mode' in peer_config:
                self.assertIn(f' echo-mode', peerconfig)
            if 'intv_echo' in peer_config:
                self.assertIn(f' echo-interval {peer_config["intv_echo"]}', peerconfig)
            if 'intv_mult' in peer_config:
                self.assertIn(f' detect-multiplier {peer_config["intv_mult"]}', peerconfig)
            if 'intv_rx' in peer_config:
                self.assertIn(f' receive-interval {peer_config["intv_rx"]}', peerconfig)
            if 'intv_tx' in peer_config:
                self.assertIn(f' transmit-interval {peer_config["intv_tx"]}', peerconfig)
            if 'shutdown' not in peer_config:
                self.assertIn(f' no shutdown', peerconfig)

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