#!/usr/bin/python3
import pathlib
from typing import List

from ansible.module_utils.generic import SYSTEMD_NETWORK_CONFIG as SYSTEMD_PATH
from ansible.module_utils.generic import Types
from ansible.module_utils.module import SystemdUnitModule

class Module(SystemdUnitModule):
    """generates an systemd-networkd link"""

    name = "systemd_link"
    module_spec = dict(
        argument_spec=dict(
            mac=Types.str(help="The Mac address of the device"),
            permanentmac=Types.str(
                help="The Permanent Mac address advertised by the device"
            ),
            path=Types.str(
                help="A shell-style glob matching the persistent path, as exposed by the udev property ID_PATH."
            ),
            driver=Types.str(
                help="A glob matching the driver currently bound to the device"
            ),
            type=Types.str(
                help="A glob matching the device type, as exposed by networkctl list"
            ),
            kind=Types.str(
                help="a glob matching the device kind, as exposed by networkctl status INTERFACE or ip -d link show INTERFACE."
            ),
            description=Types.str(help="The description for the link"),
            name=Types.str(required=True, help="The new name of the device"),
            mtu=Types.int(help="The maximum Transmission unit for the link"),
        ),
        required_one_of=(
            ("mac", "permanentmac", "path", "driver", "type", "kind"),
            ("name", "mac", "permanentmac"),
        ),
    )

    def prepare(self):
        self.__unit = None
        newname = (
            self.get("name", "") or self.get("mac", "") or self.get("permanentmac", "")
        )
        newname = newname.replace(":", "").replace("/", "-").lower()
        self.unitfile = SYSTEMD_PATH.joinpath("50-" + newname).with_suffix(".link")

    def unit(self) -> str:
        if self.__unit is None:
            self.__unit = "\n".join((self.match(), self.link()))
        return self.__unit

    def match(self) -> str:
        options = []
        if self.get("mac", False):
            options.append("MACAddress={}\n".format(self.get("mac", False)))
        if self.get("permanentmac", False):
            options.append(
                "PermanentAddress={}\n".format(self.get("permanentmac", False))
            )
        if self.get("path", False):
            options.append("Path={}\n".format(self.get("path", False)))
        if self.get("driver", False):
            options.append("Driver={}\n".format(self.get("driver", False)))
        if self.get("type", False):
            options.append("Type={}\n".format(self.get("type", False)))
        if self.get("kind", False):
            options.append("Kind={}\n".format(self.get("kind", False)))
        return "[Match]\n" + "".join(options)

    def link(self) -> str:
        options = []
        if self.get("description", False):
            options.append("Description={}\n".format(self.get("description", False)))
        if self.get("name", False):
            options.append("Name={}\n".format(self.get("name", False)))
        if self.get("mtu", False):
            options.append("MTUBytes={}\n".format(self.get("mtu", False)))
        return "[Link]\n" + "".join(options)

    def post(self):
        if not self.changed:
            return
        args = [
            "/usr/bin/udevadm",
            "trigger",
            "-c",
            "add",
        ]
        if self.module.check_mode:
            args.append("-n")
        if self.get("mac", False):
            args.append("--attr-match=address={}".format(self.get("mac")))
        if self.get("path", False):
            args.append(self.get("path"))
        self.module.run_command(args, check_rc=True)


DOCUMENTATION = """---
description:
- generates an systemd-networkd link
module: systemd_link
options:
  description:
    description:
    - The description for the link
    required: false
    type: str
  driver:
    description:
    - A glob matching the driver currently bound to the device
    required: false
    type: str
  kind:
    description:
    - a glob matching the device kind, as exposed by networkctl status INTERFACE or
      ip -d link show INTERFACE.
    required: false
    type: str
  mac:
    description:
    - The Mac address of the device
    required: false
    type: str
  mtu:
    description:
    - The maximum Transmission unit for the link
    required: false
    type: int
  name:
    description:
    - The new name of the device
    required: true
    type: str
  path:
    description:
    - A shell-style glob matching the persistent path, as exposed by the udev property
      ID_PATH.
    required: false
    type: str
  permanentmac:
    description:
    - The Permanent Mac address advertised by the device
    required: false
    type: str
  type:
    description:
    - A glob matching the device type, as exposed by networkctl list
    required: false
    type: str
short_description: generates an systemd-networkd link
"""

if __name__ == "__main__":
    Module()()