#!/usr/bin/env python3
#
# Copyright (C) 2022 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/>.

from sys import argv,exit
from vyos.configtree import ConfigTree

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

file_name = argv[1]

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

base = ['traffic-policy']
config = ConfigTree(config_file)

if not config.exists(base):
    # Nothing to do
    exit(0)

iface_config = {}

if config.exists(['interfaces']):
    def get_qos(config, interface, interface_base):
        if config.exists(interface_base):
            tmp = { interface : {} }
            if config.exists(interface_base + ['in']):
                tmp[interface]['ingress'] = config.return_value(interface_base + ['in'])
            if config.exists(interface_base + ['out']):
                tmp[interface]['egress'] = config.return_value(interface_base + ['out'])
            config.delete(interface_base)
            return tmp
        return None

    # Migrate "interface ethernet eth0 traffic-policy in|out" to "qos interface eth0 ingress|egress"
    for type in config.list_nodes(['interfaces']):
        for interface in config.list_nodes(['interfaces', type]):
            interface_base = ['interfaces', type, interface, 'traffic-policy']
            tmp = get_qos(config, interface, interface_base)
            if tmp: iface_config.append(tmp)

            vif_path = ['interfaces', type, interface, 'vif']
            if config.exists(vif_path):
                for vif in config.list_nodes(vif_path):
                    vif_interface_base = vif_path + [vif, 'traffic-policy']
                    ifname = f'{interface}.{vif}'
                    tmp = get_qos(config, ifname, vif_interface_base)
                    if tmp: iface_config.update(tmp)

            vif_s_path = ['interfaces', type, interface, 'vif-s']
            if config.exists(vif_s_path):
                for vif_s in config.list_nodes(vif_s_path):
                    vif_s_interface_base = vif_s_path + [vif_s, 'traffic-policy']
                    ifname = f'{interface}.{vif_s}'
                    tmp = get_qos(config, ifname, vif_s_interface_base)
                    if tmp: iface_config.update(tmp)

                    # vif-c interfaces MUST be migrated before their parent vif-s
                    # interface as the migrate_*() functions delete the path!
                    vif_c_path = ['interfaces', type, interface, 'vif-s', vif_s, 'vif-c']
                    if config.exists(vif_c_path):
                        for vif_c in config.list_nodes(vif_c_path):
                            vif_c_interface_base = vif_c_path + [vif_c, 'traffic-policy']
                            ifname = f'{interface}.{vif_s}.{vif_c}'
                            tmp = get_qos(config, ifname, vif_s_interface_base)
                            if tmp: iface_config.update(tmp)


# Now we have the information which interface uses which QoS policy.
# Interface binding will be moved to the qos CLi tree
config.set(['qos'])
config.copy(base, ['qos', 'policy'])
config.delete(base)


# TODO
# - remove burst from network emulator
# - convert rates to bits/s

# Now map the interface policy binding to the new CLI syntax
for interface, interface_config in iface_config.items():
    if 'ingress' in interface_config:
        config.set(['qos', 'interface', interface, 'ingress'], value=interface_config['ingress'])
    if 'egress' in interface_config:
        config.set(['qos', 'interface', interface, 'egress'], value=interface_config['egress'])

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))
    exit(1)