#!/usr/bin/python
# -*- coding: utf-8 -*-

# (c) 2017, Ansible by Red Hat, Inc
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)

from __future__ import absolute_import, division, print_function


__metaclass__ = type


DOCUMENTATION = """
module: iosxr_netconf
author: Kedar Kekan (@kedarX)
short_description: Configures NetConf sub-system service on Cisco IOS-XR devices
description:
- This module provides an abstraction that enables and configures the netconf system
  service running on Cisco IOS-XR Software. This module can be used to easily enable
  the Netconf API. Netconf provides a programmatic interface for working with configuration
  and state resources as defined in RFC 6242.
version_added: 1.0.0
extends_documentation_fragment:
- cisco.iosxr.iosxr
options:
  netconf_port:
    description:
    - This argument specifies the port the netconf service should listen on for SSH
      connections.  The default port as defined in RFC 6242 is 830.
    required: false
    type: int
    default: 830
    aliases:
    - listens_on
  netconf_vrf:
    description:
    - netconf vrf name
    required: false
    type: str
    default: default
    aliases:
    - vrf
  state:
    description:
    - Specifies the state of the C(iosxr_netconf) resource on the remote device.  If
      the I(state) argument is set to I(present) the netconf service will be configured.  If
      the I(state) argument is set to I(absent) the netconf service will be removed
      from the configuration.
    type: str
    required: false
    default: present
    choices:
    - present
    - absent
notes:
- This module works with connection C(network_cli). See L(the IOS-XR Platform Options,../network/user_guide/platform_iosxr.html).
"""

EXAMPLES = """
- name: enable netconf service on port 830
  cisco.iosxr.iosxr_netconf:
    listens_on: 830
    state: present

- name: disable netconf service
  cisco.iosxr.iosxr_netconf:
    state: absent
"""

RETURN = """
commands:
  description: Returns the command sent to the remote device
  returned: when changed is True
  type: str
  sample: 'ssh server netconf port 830'
"""
import re

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.six import iteritems

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


USE_PERSISTENT_CONNECTION = True


def map_obj_to_commands(updates):
    want, have = updates
    commands = list()

    if want["state"] == "absent":
        if have["state"] == "present":
            commands.append("no netconf-yang agent ssh")

        if "netconf_port" in have:
            commands.append("no ssh server netconf port %s" % have["netconf_port"])

        if have["netconf_vrf"]:
            for vrf in have["netconf_vrf"]:
                commands.append("no ssh server netconf vrf %s" % vrf)
    else:
        if have["state"] == "absent":
            commands.append("netconf-yang agent ssh")

        if want["netconf_port"] is not None and (want["netconf_port"] != have.get("netconf_port")):
            commands.append("ssh server netconf port %s" % want["netconf_port"])
        if want["netconf_vrf"] is not None and (want["netconf_vrf"] not in have["netconf_vrf"]):
            commands.append("ssh server netconf vrf %s" % want["netconf_vrf"])

    return commands


def parse_vrf(config):
    match = re.search(r"vrf (\w+)", config)
    if match:
        return match.group(1)


def parse_port(config):
    match = re.search(r"port (\d+)", config)
    if match:
        return int(match.group(1))


def map_config_to_obj(module):
    obj = {"state": "absent"}

    netconf_config = get_config(module, config_filter="netconf-yang agent")

    ssh_config = get_config(module, config_filter="ssh server")
    ssh_config = [
        config_line
        for config_line in (line.strip() for line in ssh_config.splitlines())
        if config_line
    ]
    obj["netconf_vrf"] = []
    for config in ssh_config:
        if "netconf port" in config:
            obj.update({"netconf_port": parse_port(config)})
        if "netconf vrf" in config:
            obj["netconf_vrf"].append(parse_vrf(config))
    if "ssh" in netconf_config and ("netconf_port" in obj or obj["netconf_vrf"]):
        obj.update({"state": "present"})

    if "ssh" in netconf_config and "netconf_port" not in obj:
        obj.update({"netconf_port": 830})

    return obj


def validate_netconf_port(value, module):
    if not 1 <= value <= 65535:
        module.fail_json(msg="netconf_port must be between 1 and 65535")


def map_params_to_obj(module):
    obj = {
        "netconf_port": module.params["netconf_port"],
        "netconf_vrf": module.params["netconf_vrf"],
        "state": module.params["state"],
    }

    for key, value in iteritems(obj):
        # validate the param value (if validator func exists)
        validator = globals().get("validate_%s" % key)
        if callable(validator):
            validator(value, module)

    return obj


def main():
    """main entry point for module execution"""
    argument_spec = dict(
        netconf_port=dict(type="int", default=830, aliases=["listens_on"]),
        netconf_vrf=dict(aliases=["vrf"], default="default"),
        state=dict(default="present", choices=["present", "absent"]),
    )

    module = AnsibleModule(argument_spec=argument_spec, supports_check_mode=True)

    warnings = list()

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

    want = map_params_to_obj(module)
    have = map_config_to_obj(module)
    commands = map_obj_to_commands((want, have))
    result["commands"] = commands

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

    module.exit_json(**result)


if __name__ == "__main__":
    main()