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

# (c) 2020, Simon Dodsley (simon@purestorage.com)
# 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 = r'''
---
module: purefb_snmp_mgr
version_added: '1.0.0'
short_description: Configure FlashBlade SNMP Managers
description:
- Manage SNMP managers on a Pure Storage FlashBlade.
- This module is not idempotent and will always modify an
  existing SNMP manager due to hidden parameters that cannot
  be compared to the play parameters.
author:
- Pure Storage Ansible Team (@sdodsley) <pure-ansible-team@purestorage.com>
options:
  name:
    description:
    - Name of SNMP Manager
    required: True
    type: str
  state:
    description:
    - Create or delete SNMP manager
    type: str
    default: present
    choices: [ absent, present ]
  auth_passphrase:
    type: str
    description:
    - SNMPv3 only. Passphrase of 8 - 32 characters.
  auth_protocol:
    type: str
    description:
    - SNMP v3 only. Hash algorithm to use
    choices: [ MD5, SHA ]
  community:
    type: str
    description:
    - SNMP v2c only. Manager community ID. Between 1 and 32 characters long.
  host:
    type: str
    description:
    - IPv4 or IPv6 address or FQDN to send trap messages to.
  user:
    type: str
    description:
    - SNMP v3 only. User ID recognized by the specified SNMP manager.
      Must be between 1 and 32 characters.
  version:
    type: str
    description:
    - Version of SNMP protocol to use for the manager.
    choices: [ v2c, v3 ]
  notification:
    type: str
    description:
    - Action to perform on event.
    default: trap
    choices: [ inform, trap ]
  privacy_passphrase:
    type: str
    description:
    - SNMPv3 only. Passphrase to encrypt SNMP messages.
      Must be between 8 and 63 non-space ASCII characters.
  privacy_protocol:
    type: str
    description:
    - SNMP v3 only. Encryption protocol to use
    choices: [ AES, DES ]
extends_documentation_fragment:
- purestorage.flashblade.purestorage.fb
'''

EXAMPLES = r'''
- name: Delete exisitng SNMP manager
  purefb_snmp_mgr:
    name: manager1
    state: absent
    fb_url: 10.10.10.2
    api_token: T-9f276a18-50ab-446e-8a0c-666a3529a1b6
- name: Create v2c SNMP manager
  purefb_snmp_mgr:
    name: manager1
    community: public
    host: 10.21.22.23
    fb_url: 10.10.10.2
    api_token: T-9f276a18-50ab-446e-8a0c-666a3529a1b6
- name: Create v3 SNMP manager
  purefb_snmp_mgr:
    name: manager2
    version: v3
    auth_protocol: MD5
    auth_passphrase: password
    host: 10.21.22.23
    fb_url: 10.10.10.2
    api_token: T-9f276a18-50ab-446e-8a0c-666a3529a1b6
- name: Update existing SNMP manager
  purefb_snmp_mgr:
    name: manager1
    community: private
    fb_url: 10.10.10.2
    api_token: T-9f276a18-50ab-446e-8a0c-666a3529a1b6
'''

RETURN = r'''
'''


HAS_PURITY_FB = True
try:
    from purity_fb import SnmpManager, SnmpV2c, SnmpV3
except ImportError:
    HAS_PURITY_FB = False


from ansible.module_utils.basic import AnsibleModule
from ansible_collections.purestorage.flashblade.plugins.module_utils.purefb import get_blade, purefb_argument_spec


MIN_REQUIRED_API_VERSION = "1.9"


def update_manager(module, blade):
    """Update SNMP Manager"""
    changed = True
    if not module.check_mode:
        changed = False
        try:
            mgr = blade.snmp_managers.list_snmp_managers(names=[module.params['name']])
        except Exception:
            module.fail_json(msg="Failed to get configuration for SNMP manager {0}.".format(module.params['name']))
        current_attr = {'community': mgr.items[0].v2c.community,
                        'notification': mgr.items[0].notification,
                        'host': mgr.items[0].host,
                        'version': mgr.items[0].version,
                        'auth_passphrase': mgr.items[0].v3.auth_passphrase,
                        'auth_protocol': mgr.items[0].v3.auth_protocol,
                        'privacy_passphrase': mgr.items[0].v3.privacy_passphrase,
                        'privacy_protocol': mgr.items[0].v3.privacy_protocol,
                        'user': mgr.items[0].v3.user,
                        }
        new_attr = {'community': module.params['community'],
                    'notification': module.params['notification'],
                    'host': module.params['host'],
                    'version': module.params['version'],
                    'auth_passphrase': module.params['auth_passphrase'],
                    'auth_protocol': module.params['auth_protocol'],
                    'privacy_passphrase': module.params['privacy_passphrase'],
                    'privacy_protocol': module.params['privacy_protocol'],
                    'user': module.params['user']
                    }
        if current_attr != new_attr:
            if new_attr['version'] == 'v2c':
                updated_v2c_attrs = SnmpV2c(community=new_attr['community'])
                updated_v2c_manager = SnmpManager(host=new_attr['host'], notification=new_attr['notification'],
                                                  version='v2c', v2c=updated_v2c_attrs
                                                  )
                try:
                    blade.snmp_managers.update_snmp_managers(names=[module.params['name']],
                                                             snmp_manager=updated_v2c_manager
                                                             )
                    changed = True
                except Exception:
                    module.fail_json(msg="Failed to update v2c SNMP manager {0}.".format(module.params['name']))
            else:
                updated_v3_attrs = SnmpV3(auth_protocol=new_attr['auth_protocol'],
                                          auth_passphrase=new_attr['auth_passphrase'],
                                          privacy_protocol=new_attr['privacy_protocol'],
                                          privacy_passphrase=new_attr['privacy_passphrase'],
                                          user=new_attr['user']
                                          )
                updated_v3_manager = SnmpManager(host=new_attr['host'], notification=new_attr['notification'],
                                                 version='v3', v3=updated_v3_attrs
                                                 )
                try:
                    blade.snmp_managers.update_snmp_managers(names=[module.params['name']],
                                                             snmp_manager=updated_v3_manager
                                                             )
                    changed = True
                except Exception:
                    module.fail_json(msg="Failed to update v3 SNMP manager {0}.".format(module.params['name']))

    module.exit_json(changed=changed)


def delete_manager(module, blade):
    """Delete SNMP Manager"""
    changed = True
    if not module.check_mode:
        try:
            blade.snmp_managers.delete_snmp_managers(names=[module.params['name']])
        except Exception:
            module.fail_json(msg='Delete SNMP manager {0} failed'.format(module.params['name']))
    module.exit_json(changed=changed)


def create_manager(module, blade):
    """Create SNMP Manager"""
    changed = True
    if not module.check_mode:
        if not module.params['version']:
            module.fail_json(msg='SNMP version required to create a new manager')
        if module.params['version'] == "v2c":
            v2_attrs = SnmpV2c(community=module.params['community'])
            new_v2_manager = SnmpManager(host=module.params['host'], notification=module.params['notification'],
                                         version='v2c', v2c=v2_attrs
                                         )
            try:
                blade.snmp_managers.create_snmp_managers(names=[module.params['name']],
                                                         snmp_manager=new_v2_manager
                                                         )
            except Exception:
                module.fail_json(msg="Failed to create v2c SNMP manager {0}.".format(module.params['name']))
        else:
            v3_attrs = SnmpV3(auth_protocol=module.params['auth_protocol'],
                              auth_passphrase=module.params['auth_passphrase'],
                              privacy_protocol=module.params['privacy_protocol'],
                              privacy_passphrase=module.params['privacy_passphrase'],
                              user=module.params['user']
                              )
            new_v3_manager = SnmpManager(host=module.params['host'], notification=module.params['notification'],
                                         version='v3', v3=v3_attrs
                                         )
            try:
                blade.snmp_managers.create_snmp_managers(names=[module.params['name']],
                                                         snmp_manager=new_v3_manager
                                                         )
            except Exception:
                module.fail_json(msg="Failed to create v3 SNMP manager {0}.".format(module.params['name']))
    module.exit_json(changed=changed)


def main():
    argument_spec = purefb_argument_spec()
    argument_spec.update(dict(
        name=dict(type='str', required=True),
        host=dict(type='str'),
        state=dict(type='str', default='present', choices=['absent', 'present']),
        user=dict(type='str'),
        notification=dict(type='str', choices=['inform', 'trap'], default='trap'),
        auth_passphrase=dict(type='str', no_log=True),
        auth_protocol=dict(type='str', choices=['MD5', 'SHA']),
        privacy_passphrase=dict(type='str', no_log=True),
        privacy_protocol=dict(type='str', choices=['AES', 'DES']),
        version=dict(type='str', choices=['v2c', 'v3']),
        community=dict(type='str'),
    ))

    required_together = [['auth_passphrase', 'auth_protocol'],
                         ['privacy_passphrase', 'privacy_protocol']]
    required_if = [['version', 'v2c', ['community', 'host']],
                   ['version', 'v3', ['host', 'user']]]

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

    state = module.params['state']
    blade = get_blade(module)
    api_version = blade.api_version.list_versions().versions

    if MIN_REQUIRED_API_VERSION not in api_version:
        module.fail_json(msg="Purity//FB must be upgraded to support this module.")

    if not HAS_PURITY_FB:
        module.fail_json(msg='purity_fb SDK is required for this module')

    mgr_configured = False
    mgrs = blade.snmp_managers.list_snmp_managers()
    for mgr in range(0, len(mgrs.items)):
        if mgrs.items[mgr].name == module.params['name']:
            mgr_configured = True
            break
    if module.params['version'] == "v3":
        if module.params['auth_passphrase'] and (8 > len(module.params['auth_passphrase']) > 32):
            module.fail_json(msg="auth_password must be between 8 and 32 characters")
        if module.params['privacy_passphrase'] and 8 > len(module.params['privacy_passphrase']) > 63:
            module.fail_json(msg="privacy_password must be between 8 and 63 characters")
    if state == 'absent' and mgr_configured:
        delete_manager(module, blade)
    elif mgr_configured and state == 'present':
        update_manager(module, blade)
    elif not mgr_configured and state == 'present':
        create_manager(module, blade)
    else:
        module.exit_json(changed=False)


if __name__ == '__main__':
    main()
