# This file is part of naxalnet.
# Copyright (C) 2021 The naxalnet Authors

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# 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/>.

"""
network.py
----------

This submodule manages the systemd-networkd configuration.
TODO: Add more details
"""

from pathlib import Path
from dasbus.connection import SystemMessageBus


NETWORKD_BUS = "org.freedesktop.network1"
NETWORKD_PATH = "/org/freedesktop/network1"


class NetworkD:
    """control systemd-networkd"""

    def __init__(self, runtime_dir="/run/systemd/network", bus=SystemMessageBus()):
        self._bus = bus
        self.proxy_reload()
        self.files = []
        self.variables = {}
        print(runtime_dir)
        self.runtime_path = Path(runtime_dir)
        print(self.runtime_path)

    def set_vars(self, **variables):
        """set the variables to replace with str.format"""
        self.variables = variables

    def proxy_reload(self) -> None:
        """reload the proxy"""
        self.proxy = self._bus.get_proxy(NETWORKD_BUS, NETWORKD_PATH)

    def reload(self) -> None:
        """reload the systemd-networkd configuration"""
        self.proxy.Reload()

    def add_config(self, name: str) -> None:
        """add config file to runtime directory and reload networkd"""
        source = Path(name)
        destination = self.runtime_path / source.name

        # Substitute variables in the config
        text = source.read_text(encoding="utf-8").format(**self.variables)
        # now write it to a runtime config
        print(self.runtime_path / name)
        destination.write_text(text, encoding="utf-8")
        self.reload()
        self.files.append(name)

    def is_routable(self) -> bool:
        """returns true if any interface is routable"""
        return self.proxy.AddressState == "routable"