#!/usr/bin/python
# Copyright: Ansible Project
# 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


ANSIBLE_METADATA = {'metadata_version': '1.1',
                    'status': ['preview'],
                    'supported_by': 'community'}

DOCUMENTATION = '''
---
module: icx_user
author: "Ruckus Wireless (@Commscope)"
short_description: Manage the user accounts on Ruckus ICX 7000 series switches.
description:
  - This module creates or updates user account on network devices. It allows playbooks to manage
    either individual usernames or the aggregate of usernames in the
    current running config. It also supports purging usernames from the
    configuration that are not explicitly defined.
notes:
  - Tested against ICX 10.1.
  - For information on using ICX platform, see L(the ICX OS Platform Options guide,../network/user_guide/platform_icx.html).
options:
  aggregate:
    description:
      - The set of username objects to be configured on the remote
        ICX device. The list entries can either be the username
        or a hash of username and properties. This argument is mutually
        exclusive with the C(name) argument.
    aliases: ['users', 'collection']
    type: list
    suboptions:
      name:
        description:
          - The username to be configured on the ICX device.
        required: true
        type: str
      configured_password:
        description: The password to be configured on the ICX device.
        type: str
      update_password:
        description:
          - This argument will instruct the module when to change the password. When
            set to C(always), the password will always be updated in the device
            and when set to C(on_create) the password will be updated only if
            the username is created.
        choices: ['on_create', 'always']
        type: str
      privilege:
        description:
          - The privilege level to be granted to the user
        choices: ['0', '4', '5']
        type: str
      nopassword:
        description:
          - Defines the username without assigning
            a password. This will allow the user to login to the system
            without being authenticated by a password.
        type: bool
      state:
        description:
          - Configures the state of the username definition
            as it relates to the device operational configuration. When set
            to I(present), the username(s) should be configured in the device active
            configuration and when set to I(absent) the username(s) should not be
            in the device active configuration
        choices: ['present', 'absent']
        type: str
      access_time:
        description:
          - This parameter indicates the time the file's access time should be set to.
           Should be preserve when no modification is required, YYYYMMDDHHMM.SS when using default time format, or now.
           Default is None meaning that preserve is the default for state=[file,directory,link,hard] and now is default for state=touch
        type: str
      check_running_config:
        description:
          - Check running configuration. This can be set as environment variable.
           Module will use environment variable value(default:True), unless it is overridden, by specifying it as module parameter.
        type: bool
  name:
    description:
      - The username to be configured on the ICX device.
    required: true
    type: str
  configured_password:
    description: The password to be configured on the ICX device.
    type: str
  update_password:
    description:
      - This  argument will instruct the module when to change the password. When
        set to C(always), the password will always be updated in the device
        and when set to C(on_create) the password will be updated only if
        the username is created.
    default: always
    choices: ['on_create', 'always']
    type: str
  privilege:
    description:
      - The privilege level to be granted to the user
    default: 0
    choices: ['0', '4', '5']
    type: str
  nopassword:
    description:
      - Defines the username without assigning
        a password. This will allow the user to login to the system
        without being authenticated by a password.
    type: bool
  purge:
    description:
      - If set to true module will remove any previously
        configured usernames on the device except the current defined set of users.
    type: bool
    default: false
  state:
    description:
      - Configures the state of the username definition
        as it relates to the device operational configuration. When set
        to I(present), the username(s) should be configured in the device active
        configuration and when set to I(absent) the username(s) should not be
        in the device active configuration
    default: present
    choices: ['present', 'absent']
    type: str
  access_time:
    description:
      - This parameter indicates the time the file's access time should be set to.
       Should be preserve when no modification is required, YYYYMMDDHHMM.SS when using default time format, or now.
       Default is None meaning that preserve is the default for state=[file,directory,link,hard] and now is default for state=touch
    type: str
  check_running_config:
    description:
      - Check running configuration. This can be set as environment variable.
       Module will use environment variable value(default:True), unless it is overridden, by specifying it as module parameter.
    type: bool
    default: yes
'''

EXAMPLES = """
- name: create a new user without password
  icx_user:
    name: user1
    nopassword: true

- name: create a new user with password
  icx_user:
    name: user1
    configured_password: 'newpassword'

- name: remove users
  icx_user:
    name: user1
    state: absent

- name: set user privilege level to 5
  icx_user:
    name: user1
    privilege: 5
"""

RETURN = """
commands:
  description: The list of configuration mode commands to send to the device
  returned: always
  type: list
  sample:
    - username ansible nopassword
    - username ansible password-string alethea123
    - no username ansible
    - username ansible privilege 5
    - username ansible enable
"""

from copy import deepcopy

import re
import base64
import hashlib

from functools import partial

from ansible.module_utils.basic import AnsibleModule, env_fallback
from ansible_collections.ansible.netcommon.plugins.module_utils.network.common.utils import remove_default_spec
from ansible.module_utils.connection import exec_command
from ansible.module_utils.six import iteritems
from ansible_collections.community.general.plugins.module_utils.network.icx.icx import get_config, load_config


def get_param_value(key, item, module):
    if not item.get(key):
        value = module.params[key]

    else:
        value_type = module.argument_spec[key].get('type', 'str')
        type_checker = module._CHECK_ARGUMENT_TYPES_DISPATCHER[value_type]
        type_checker(item[key])
        value = item[key]

    validator = globals().get('validate_%s' % key)
    if all((value, validator)):
        validator(value, module)

    return value


def map_params_to_obj(module):
    users = module.params['aggregate']
    if not users:
        if not module.params['name'] and module.params['purge']:
            return list()
        elif not module.params['name']:
            module.fail_json(msg='username is required')
        else:
            aggregate = [{'name': module.params['name']}]
    else:
        aggregate = list()
        for item in users:
            if not isinstance(item, dict):
                aggregate.append({'name': item})
            elif 'name' not in item:
                module.fail_json(msg='name is required')
            else:
                aggregate.append(item)

    objects = list()

    for item in aggregate:
        get_value = partial(get_param_value, item=item, module=module)
        item['configured_password'] = get_value('configured_password')
        item['nopassword'] = get_value('nopassword')
        item['privilege'] = get_value('privilege')
        item['state'] = get_value('state')
        objects.append(item)

    return objects


def parse_privilege(data):
    match = re.search(r'privilege (\S)', data, re.M)
    if match:
        return match.group(1)


def map_config_to_obj(module):
    compare = module.params['check_running_config']
    data = get_config(module, flags=['| include username'], compare=compare)

    match = re.findall(r'(?:^(?:u|\s{2}u))sername (\S+)', data, re.M)
    if not match:
        return list()

    instances = list()

    for user in set(match):
        regex = r'username %s .+$' % user
        cfg = re.findall(regex, data, re.M)
        cfg = '\n'.join(cfg)
        obj = {
            'name': user,
            'state': 'present',
            'nopassword': 'nopassword' in cfg,
            'configured_password': None,
            'privilege': parse_privilege(cfg)
        }
        instances.append(obj)

    return instances


def map_obj_to_commands(updates, module):
    commands = list()
    state = module.params['state']
    update_password = module.params['update_password']

    def needs_update(want, have, x):
        return want.get(x) and (want.get(x) != have.get(x))

    def add(command, want, x):
        command.append('username %s %s' % (want['name'], x))
    for update in updates:
        want, have = update
        if want['state'] == 'absent':
            commands.append(user_del_cmd(want['name']))

        if needs_update(want, have, 'privilege'):
            add(commands, want, 'privilege %s password %s' % (want['privilege'], want['configured_password']))
        else:
            if needs_update(want, have, 'configured_password'):
                if update_password == 'always' or not have:
                    add(commands, want, '%spassword %s' % ('privilege ' + str(have.get('privilege')) +
                                                           " " if have.get('privilege') is not None else '', want['configured_password']))

        if needs_update(want, have, 'nopassword'):
            if want['nopassword']:
                add(commands, want, 'nopassword')

        if needs_update(want, have, 'access_time'):
            add(commands, want, 'access-time %s' % want['access_time'])

        if needs_update(want, have, 'expiry_days'):
            add(commands, want, 'expires %s' % want['expiry_days'])

    return commands


def update_objects(want, have):
    updates = list()
    for entry in want:
        item = next((i for i in have if i['name'] == entry['name']), None)

        if all((item is None, entry['state'] == 'present')):
            updates.append((entry, {}))

        elif all((have == [], entry['state'] == 'absent')):
            for key, value in iteritems(entry):
                if key not in ['update_password']:
                    updates.append((entry, item))
                    break
        elif item:
            for key, value in iteritems(entry):
                if key not in ['update_password']:
                    if value is not None and value != item.get(key):
                        updates.append((entry, item))
                        break
    return updates


def user_del_cmd(username):
    return 'no username %s' % username


def main():
    """entry point for module execution
    """
    element_spec = dict(
        name=dict(),

        configured_password=dict(no_log=True),
        nopassword=dict(type='bool', default=False),
        update_password=dict(default='always', choices=['on_create', 'always']),
        privilege=dict(type='str', choices=['0', '4', '5']),
        access_time=dict(type='str'),
        state=dict(default='present', choices=['present', 'absent']),
        check_running_config=dict(default=True, type='bool', fallback=(env_fallback, ['ANSIBLE_CHECK_ICX_RUNNING_CONFIG']))
    )
    aggregate_spec = deepcopy(element_spec)
    aggregate_spec['name'] = dict(required=True)

    remove_default_spec(aggregate_spec)

    argument_spec = dict(
        aggregate=dict(type='list', elements='dict', options=aggregate_spec, aliases=['users', 'collection']),
        purge=dict(type='bool', default=False)
    )

    argument_spec.update(element_spec)

    mutually_exclusive = [('name', 'aggregate')]

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

    result = {'changed': False}
    exec_command(module, 'skip')
    want = map_params_to_obj(module)
    have = map_config_to_obj(module)
    commands = map_obj_to_commands(update_objects(want, have), module)

    if module.params['purge']:
        want_users = [x['name'] for x in want]
        have_users = [x['name'] for x in have]
        for item in set(have_users).difference(want_users):
            if item != 'admin':
                commands.append(user_del_cmd(item))

    result["commands"] = commands

    if commands:
        if not module.check_mode:
            load_config(module, commands)
        result['changed'] = True
    module.exit_json(**result)


if __name__ == '__main__':
    main()