#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# This file is part of Ansible
#
# Ansible 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.
#
# Ansible 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 Ansible.  If not, see <http://www.gnu.org/licenses/>.
#
from __future__ import absolute_import, division, print_function

__metaclass__ = type


DOCUMENTATION = """
module: vyos_system
author: Nathaniel Case (@Qalthos)
short_description: Run `set system` commands on VyOS devices
description:
- Runs one or more commands on remote devices running VyOS. This module can also be
  introspected to validate key parameters before returning successfully.
version_added: 1.0.0
extends_documentation_fragment:
- vyos.vyos.vyos
notes:
- Tested against VyOS 1.1.8 (helium).
- This module works with connection C(ansible.netcommon.network_cli). See L(the VyOS OS Platform Options,../network/user_guide/platform_vyos.html).
options:
  host_name:
    description:
    - Configure the device hostname parameter. This option takes an ASCII string value.
    type: str
  domain_name:
    description:
    - The new domain name to apply to the device.
    type: str
  name_server:
    description:
    - A list of name servers to use with the device. Mutually exclusive with I(domain_search)
    type: list
    elements: str
    aliases:
    - name_servers
  domain_search:
    description:
    - A list of domain names to search. Mutually exclusive with I(name_server)
    type: list
    elements: str
  state:
    description:
    - Whether to apply (C(present)) or remove (C(absent)) the settings.
    default: present
    type: str
    choices:
    - present
    - absent
"""

RETURN = """
commands:
  description: The list of configuration mode commands to send to the device
  returned: always
  type: list
  sample:
    - set system hostname vyos01
    - set system domain-name foo.example.com
"""

EXAMPLES = """
- name: configure hostname and domain-name
  vyos.vyos.vyos_system:
    host_name: vyos01
    domain_name: test.example.com

- name: remove all configuration
  vyos.vyos.vyos_system:
    state: absent

- name: configure name servers
  vyos.vyos.vyos_system: name_servers - 8.8.8.8 - 8.8.4.4
- name: configure domain search suffixes
  vyos.vyos.vyos_system:
    domain_search:
    - sub1.example.com
    - sub2.example.com
"""

from ansible.module_utils.basic import AnsibleModule

from ansible_collections.vyos.vyos.plugins.module_utils.network.vyos.vyos import (
    get_config,
    load_config,
)


def spec_key_to_device_key(key):
    device_key = key.replace("_", "-")

    # domain-search is longer than just it's key
    if device_key == "domain-search":
        device_key += " domain"

    return device_key


def config_to_dict(module):
    data = get_config(module)

    config = {"domain_search": [], "name_server": []}

    for line in data.split("\n"):
        if line.startswith("set system host-name"):
            config["host_name"] = line[22:-1]
        elif line.startswith("set system domain-name"):
            config["domain_name"] = line[24:-1]
        elif line.startswith("set system domain-search domain"):
            config["domain_search"].append(line[33:-1])
        elif line.startswith("set system name-server"):
            config["name_server"].append(line[24:-1])

    return config


def spec_to_commands(want, have):
    commands = []

    state = want.pop("state")

    # state='absent' by itself has special meaning
    if state == "absent" and all(v is None for v in want.values()):
        # Clear everything
        for key in have:
            commands.append("delete system %s" % spec_key_to_device_key(key))

    for key in want:
        if want[key] is None:
            continue

        current = have.get(key)
        proposed = want[key]
        device_key = spec_key_to_device_key(key)

        # These keys are lists which may need to  be reconciled with the device
        if key in ["domain_search", "name_server"]:
            if not proposed:
                # Empty list was passed, delete all values
                commands.append("delete system %s" % device_key)
            for config in proposed:
                if state == "absent" and config in current:
                    commands.append("delete system %s '%s'" % (device_key, config))
                elif state == "present" and config not in current:
                    commands.append("set system %s '%s'" % (device_key, config))
        else:
            if state == "absent" and current and proposed:
                commands.append("delete system %s" % device_key)
            elif state == "present" and proposed and proposed != current:
                commands.append("set system %s '%s'" % (device_key, proposed))

    return commands


def map_param_to_obj(module):
    return {
        "host_name": module.params["host_name"],
        "domain_name": module.params["domain_name"],
        "domain_search": module.params["domain_search"],
        "name_server": module.params["name_server"],
        "state": module.params["state"],
    }


def main():
    argument_spec = dict(
        host_name=dict(type="str"),
        domain_name=dict(type="str"),
        domain_search=dict(type="list", elements="str"),
        name_server=dict(type="list", aliases=["name_servers"], elements="str"),
        state=dict(type="str", default="present", choices=["present", "absent"]),
    )

    module = AnsibleModule(
        argument_spec=argument_spec,
        supports_check_mode=True,
        mutually_exclusive=[("domain_name", "domain_search")],
    )

    warnings = list()

    result = {"changed": False, "warnings": warnings}

    want = map_param_to_obj(module)
    have = config_to_dict(module)

    commands = spec_to_commands(want, have)
    result["commands"] = commands

    if commands:
        commit = not module.check_mode
        load_config(module, commands, commit=commit)
        result["changed"] = True

    module.exit_json(**result)


if __name__ == "__main__":
    main()