#!/usr/bin/python
# -*- coding: utf-8 -*-
# Copyright: (c) 2020, Infinidat(info@infinidat.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: infini_export
version_added: 2.3
short_description: Create, Delete or Modify NFS Exports on Infinibox
description:
    - This module creates, deletes or modifies NFS exports on Infinibox.
author: Gregory Shulov (@GR360RY)
options:
  name:
    description:
      - Export name. Must start with a forward slash, e.g. name=/data.
    required: true
  state:
    description:
      - Creates/Modifies export when present, removes when absent, or provides
        export details with stat.
    required: false
    default: "present"
    choices: [ "stat", "present", "absent" ]
  client_list:
    description:
      - List of dictionaries with client entries. See examples.
        Check infini_export_client module to modify individual NFS client entries for export.
    default: "All Hosts(*), RW, no_root_squash: True"
    required: false
  filesystem:
    description:
      - Name of exported file system.
    required: true
extends_documentation_fragment:
    - infinibox
requirements:
    - munch
'''

EXAMPLES = r'''
- name: Export bar filesystem under foo pool as /data
  infini_export:
    name: /data01
    filesystem: foo
    state: present  # Default
    user: admin
    password: secret
    system: ibox001

- name: Get status of export bar filesystem under foo pool as /data
  infini_export:
    name: /data01
    filesystem: foo
    state: stat
    user: admin
    password: secret
    system: ibox001

- name: Remove export bar filesystem under foo pool as /data
  infini_export:
    name: /data01
    filesystem: foo
    state: absent
    user: admin
    password: secret
    system: ibox001

- name: Export and specify client list explicitly
  infini_export:
    name: /data02
    filesystem: foo
    client_list:
      - client: 192.168.0.2
        access: RW
        no_root_squash: True
      - client: 192.168.0.100
        access: RO
        no_root_squash: False
      - client: 192.168.0.10-192.168.0.20
        access: RO
        no_root_squash: False
    system: ibox001
    user: admin
    password: secret
'''

# RETURN = r''' # '''
import traceback

MUNCH_IMP_ERR = None
try:
    from munch import unmunchify
    HAS_MUNCH = True
except ImportError:
    MUNCH_IMP_ERR = traceback.format_exc()
    HAS_MUNCH = False

from ansible.module_utils.basic import AnsibleModule, missing_required_lib
from ansible_collections.infinidat.infinibox.plugins.module_utils.infinibox import \
    HAS_INFINISDK, api_wrapper, infinibox_argument_spec, \
    get_system, get_filesystem, get_export, merge_two_dicts


def transform(d):
    return frozenset(d.items())


def create_export(module, export, filesystem, system):
    """ Create new filesystem or update existing one"""
    assert not export
    changed = False

    name = module.params['name']
    client_list = module.params['client_list']

    if not module.check_mode:
        export = system.exports.create(export_path=name, filesystem=filesystem)
        if client_list:
            export.update_permissions(client_list)
    changed = True
    return changed


@api_wrapper
def update_export(module, export, filesystem, system):
    """ Create new filesystem or update existing one"""
    assert export
    changed = False

    name = module.params['name']
    client_list = module.params['client_list']

    if client_list:
        if set(map(transform, unmunchify(export.get_permissions()))) \
                != set(map(transform, client_list)):
            if not module.check_mode:
                export.update_permissions(client_list)
            changed = True
    return changed


@api_wrapper
def delete_export(module, export):
    """ Delete file system"""
    if not module.check_mode:
        export.delete()
    changed = True
    return changed


def get_sys_exp_fs(module):
    system = get_system(module)
    filesystem = get_filesystem(module, system)
    export = get_export(module, system)
    return (system, export, filesystem)


def get_export_fields(export):
    fields = export.get_fields() #from_cache=True, raw_value=True)
    export_id = fields.get('id', None)
    permissions = fields.get('permissions', None)
    enabled = fields.get('enabled', None)
    field_dict = dict(
        id=export_id,
        permissions=permissions,
        enabled=enabled,
    )
    return field_dict


def handle_stat(module):
    """
    Gather stats on export and return. Changed is always False.
    """
    system, export, filesystem = get_sys_exp_fs(module)
    if not export:
        module.fail_json(msg='Export "{}" of file system "{}" not found'.format(
            module.params['name'],
            module.params['filesystem'],
        ))

    field_dict = get_export_fields(export)
    result = dict(
        changed=False,
        msg='File system stat found'
    )
    result = merge_two_dicts(result, field_dict)
    module.exit_json(**result)


def handle_present(module):
    system, export, filesystem = get_sys_exp_fs(module)
    if not filesystem:
        module.fail_json(msg='File system {0} not found'.format(module.params['filesystem']))
    elif not export:
        changed = create_export(module, export, filesystem, system)
        module.exit_json(changed=changed, msg="File system export created")
    else:
        changed = update_export(module, export, filesystem, system)
        module.exit_json(changed=changed, msg="File system export updated")


def handle_absent(module):
    system, export, filesystem = get_sys_exp_fs(module)
    if not export:
        changed = False
        msg="Export of {0} already absent".format(module.params['filesystem'])
        module.exit_json(changed=changed, msg=msg)
    else:
        changed = delete_export(module, export)
        msg="Export of {0} deleted".format(module.params['filesystem'])
        module.exit_json(changed=changed, msg=msg)


def execute_state(module):
    state = module.params['state']
    try:
        if state == 'stat':
            handle_stat(module)
        elif state == 'present':
            handle_present(module)
        elif state == 'absent':
            handle_absent(module)
        else:
            module.fail_json(msg='Internal handler error. Invalid state: {0}'.format(state))
    finally:
        system = get_system(module)
        system.logout()


def main():
    argument_spec = infinibox_argument_spec()
    argument_spec.update(
        dict(
            name=dict(required=True),
            state=dict(default='present', choices=['stat', 'present', 'absent']),
            filesystem=dict(required=True),
            client_list=dict(type='list')
        )
    )

    module = AnsibleModule(argument_spec, supports_check_mode=True)

    if not HAS_INFINISDK:
        module.fail_json(msg=missing_required_lib('infinisdk'))
    if not HAS_MUNCH:
        module.fail_json(msg=missing_required_lib('munch'), exception=MUNCH_IMP_ERR)

    execute_state(module)


if __name__ == '__main__':
    main()