#!/usr/bin/python
# -*- coding: utf-8 -*-
# (c) 2017, 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 = '''
---
module: purefa_snap
version_added: 2.4
short_description:  Create or Delete volume snapshots on Pure Storage FlashArray
description:
    - This module creates or deletes volume snapshots and creates volumes from snapshots on Pure Storage FlashArray.
author: Simon Dodsley (@simondodsley)
options:
  name:
    description:
      - Source volume name of snapshot
    required: true
  suffix:
    description:
      - Suffix of snapshot name
    required: false
  target:
    description:
      - Name of target volume if creating from snapshot
    required: false
  overwrite:
    description:
      - Define whether to overwrite existing volume when creating from snapshot
    required: false
    default: false
    type: bool
  state:
    description:
      - Create or delete volume snapshot
    required: false
    default: present
    choices: [ "present", "absent", "copy" ]
  eradicate:
    description:
      - Define whether to eradicate the snapshot on delete or leave in trash
    required: false
    default: false
    type: bool
extends_documentation_fragment:
    - purestorage
'''

EXAMPLES = '''
- name: Create snapshot foo.ansible
  purefa_snap:
    name: foo
    suffix: ansible
    state: present
    fa_url: 10.10.10.2
    fa_api_token: e31060a7-21fc-e277-6240-25983c6c4592

- name: Create R/W clone foo_clone from snapshot foo.snap
  purefa_snap:
    name: foo
    suffix: snap
    target: foo_clone
    state: copy
    fa_url: 10.10.10.2
    fa_api_token: e31060a7-21fc-e277-6240-25983c6c4592

- name: Overwrite existing volume foo_clone with snapshot foo.snap
  purefa_snap:
    name: foo
    suffix: snap
    target: foo_clone
    state: copy
    overwrite: true
    fa_url: 10.10.10.2
    fa_api_token: e31060a7-21fc-e277-6240-25983c6c4592

- name: Delete and eradicate snapshot named foo.snap
  purefa_snap:
    name: foo
    suffix: snap
    eradicate: true
    state: absent
    fa_url: 10.10.10.2
    fa_api_token: e31060a7-21fc-e277-6240-25983c6c4592'''

RETURN = '''
'''

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.pure import get_system, purefa_argument_spec

from datetime import datetime

HAS_PURESTORAGE = True
try:
    from purestorage import purestorage
except ImportError:
    HAS_PURESTORAGE = False


def get_volume(module, array):
    """Return Volume or None"""
    try:
        return array.get_volume(module.params['name'])
    except:
        return None


def get_target(module, array):
    """Return Volume or None"""
    try:
        return array.get_volume(module.params['target'])
    except:
        return None


def get_snapshot(module, array):
    """Return Snapshot or None"""
    try:
        snapname = module.params['name'] + "." + module.params['suffix']
        for s in array.get_volume(module.params['name'], snap='true'):
            if s['name'] == snapname:
                return snapname
                break
    except:
        return None


def create_snapshot(module, array):
    """Create Snapshot"""
    if not module.check_mode:
        array.create_snapshot(module.params['name'], suffix=module.params['suffix'])
    module.exit_json(changed=True)


def create_from_snapshot(module, array):
    """Create Volume from Snapshot"""
    if not module.check_mode:
        source = module.params['name'] + "." + module.params['suffix']
        tgt = get_target(module, array)
        if tgt is None:
            changed = True
            array.copy_volume(source,
                              module.params['target'])
        elif tgt is not None and module.params['overwrite']:
            changed = True
            array.copy_volume(source,
                              module.params['target'],
                              overwrite=module.params['overwrite'])
        elif tgt is not None and not module.params['overwrite']:
            changed = False
    module.exit_json(changed=changed)


def update_snapshot(module, array):
    """Update Snapshot"""
    changed = False
    module.exit_json(changed=changed)


def delete_snapshot(module, array):
    """ Delete Snapshot"""
    if not module.check_mode:
        snapname = module.params['name'] + "." + module.params['suffix']
        array.destroy_volume(snapname)
        if module.params['eradicate']:
            array.eradicate_volume(snapname)
    module.exit_json(changed=True)


def main():
    argument_spec = purefa_argument_spec()
    argument_spec.update(
        dict(
            name=dict(required=True),
            suffix=dict(),
            target=dict(),
            overwrite=dict(default='false', type='bool'),
            eradicate=dict(default='false', type='bool'),
            state=dict(default='present', choices=['present', 'absent', 'copy']),
        )
    )

    required_if = [('state', 'copy', ['target', 'suffix'])]

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

    if not HAS_PURESTORAGE:
        module.fail_json(msg='purestorage sdk is required for this module in volume')

    if module.params['suffix'] is None:
        suffix = "snap-" + str((datetime.utcnow() - datetime(1970, 1, 1, 0, 0, 0, 0)).total_seconds())
        module.params['suffix'] = suffix.replace(".", "")
    state = module.params['state']
    array = get_system(module)
    volume = get_volume(module, array)
    target = get_target(module, array)
    snap = get_snapshot(module, array)

    if state == 'present' and volume and not snap:
        create_snapshot(module, array)
    elif state == 'present' and volume and snap:
        update_snapshot(module, array)
    elif state == 'present' and not volume:
        update_snapshot(module, array)
    elif state == 'copy' and snap:
        create_from_snapshot(module, array)
    elif state == 'copy' and not snap:
        update_snapshot(module, array)
    elif state == 'absent' and snap:
        delete_snapshot(module, array)
    elif state == 'absent' and not snap:
        module.exit_json(changed=False)


if __name__ == '__main__':
    main()