#!/usr/bin/python

#
# Copyright (c) 2015 CenturyLink
#
# This file is part of Ansible.
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>
#

ANSIBLE_METADATA = {'status': ['preview'],
                    'supported_by': 'community',
                    'version': '1.0'}

DOCUMENTATION = '''
module: clc_aa_policy
short_description: Create or Delete Anti Affinity Policies at CenturyLink Cloud.
description:
  - An Ansible module to Create or Delete Anti Affinity Policies at CenturyLink Cloud.
version_added: "2.0"
options:
  name:
    description:
      - The name of the Anti Affinity Policy.
    required: True
  location:
    description:
      - Datacenter in which the policy lives/should live.
    required: True
  state:
    description:
      - Whether to create or delete the policy.
    required: False
    default: present
    choices: ['present','absent']
  wait:
    description:
      - Whether to wait for the tasks to finish before returning.
    default: True
    required: False
    choices: [True, False]
requirements:
    - python = 2.7
    - requests >= 2.5.0
    - clc-sdk
author: "CLC Runner (@clc-runner)"
notes:
    - To use this module, it is required to set the below environment variables which enables access to the
      Centurylink Cloud
          - CLC_V2_API_USERNAME, the account login id for the centurylink cloud
          - CLC_V2_API_PASSWORD, the account password for the centurylink cloud
    - Alternatively, the module accepts the API token and account alias. The API token can be generated using the
      CLC account login and password via the HTTP api call @ https://api.ctl.io/v2/authentication/login
          - CLC_V2_API_TOKEN, the API token generated from https://api.ctl.io/v2/authentication/login
          - CLC_ACCT_ALIAS, the account alias associated with the centurylink cloud
    - Users can set CLC_V2_API_URL to specify an endpoint for pointing to a different CLC environment.
'''

EXAMPLES = '''
# Note - You must set the CLC_V2_API_USERNAME And CLC_V2_API_PASSWD Environment variables before running these examples

---
- name: Create AA Policy
  hosts: localhost
  gather_facts: False
  connection: local
  tasks:
    - name: Create an Anti Affinity Policy
      clc_aa_policy:
        name: Hammer Time
        location: UK3
        state: present
      register: policy

    - name: debug
      debug:
        var: policy

---
- name: Delete AA Policy
  hosts: localhost
  gather_facts: False
  connection: local
  tasks:
    - name: Delete an Anti Affinity Policy
      clc_aa_policy:
        name: Hammer Time
        location: UK3
        state: absent
      register: policy

    - name: debug
      debug:
        var: policy
'''

RETURN = '''
policy:
    description: The anti affinity policy information
    returned: success
    type: dict
    sample:
        {
           "id":"1a28dd0988984d87b9cd61fa8da15424",
           "name":"test_aa_policy",
           "location":"UC1",
           "links":[
              {
                 "rel":"self",
                 "href":"/v2/antiAffinityPolicies/wfad/1a28dd0988984d87b9cd61fa8da15424",
                 "verbs":[
                    "GET",
                    "DELETE",
                    "PUT"
                 ]
              },
              {
                 "rel":"location",
                 "href":"/v2/datacenters/wfad/UC1",
                 "id":"uc1",
                 "name":"UC1 - US West (Santa Clara)"
              }
           ]
        }
'''

__version__ = '${version}'

import os

from distutils.version import LooseVersion

try:
    import requests
except ImportError:
    REQUESTS_FOUND = False
else:
    REQUESTS_FOUND = True

#
#  Requires the clc-python-sdk.
#  sudo pip install clc-sdk
#
try:
    import clc as clc_sdk
    from clc import CLCException
except ImportError:
    CLC_FOUND = False
    clc_sdk = None
else:
    CLC_FOUND = True

from ansible.module_utils.basic import AnsibleModule


class ClcAntiAffinityPolicy:

    clc = clc_sdk
    module = None

    def __init__(self, module):
        """
        Construct module
        """
        self.module = module
        self.policy_dict = {}

        if not CLC_FOUND:
            self.module.fail_json(
                msg='clc-python-sdk required for this module')
        if not REQUESTS_FOUND:
            self.module.fail_json(
                msg='requests library is required for this module')
        if requests.__version__ and LooseVersion(requests.__version__) < LooseVersion('2.5.0'):
            self.module.fail_json(
                msg='requests library  version should be >= 2.5.0')

        self._set_user_agent(self.clc)

    @staticmethod
    def _define_module_argument_spec():
        """
        Define the argument spec for the ansible module
        :return: argument spec dictionary
        """
        argument_spec = dict(
            name=dict(required=True),
            location=dict(required=True),
            wait=dict(default=True),
            state=dict(default='present', choices=['present', 'absent']),
        )
        return argument_spec

    # Module Behavior Goodness
    def process_request(self):
        """
        Process the request - Main Code Path
        :return: Returns with either an exit_json or fail_json
        """
        p = self.module.params

        self._set_clc_credentials_from_env()
        self.policy_dict = self._get_policies_for_datacenter(p)

        if p['state'] == "absent":
            changed, policy = self._ensure_policy_is_absent(p)
        else:
            changed, policy = self._ensure_policy_is_present(p)

        if hasattr(policy, 'data'):
            policy = policy.data
        elif hasattr(policy, '__dict__'):
            policy = policy.__dict__

        self.module.exit_json(changed=changed, policy=policy)

    def _set_clc_credentials_from_env(self):
        """
        Set the CLC Credentials on the sdk by reading environment variables
        :return: none
        """
        env = os.environ
        v2_api_token = env.get('CLC_V2_API_TOKEN', False)
        v2_api_username = env.get('CLC_V2_API_USERNAME', False)
        v2_api_passwd = env.get('CLC_V2_API_PASSWD', False)
        clc_alias = env.get('CLC_ACCT_ALIAS', False)
        api_url = env.get('CLC_V2_API_URL', False)

        if api_url:
            self.clc.defaults.ENDPOINT_URL_V2 = api_url

        if v2_api_token and clc_alias:
            self.clc._LOGIN_TOKEN_V2 = v2_api_token
            self.clc._V2_ENABLED = True
            self.clc.ALIAS = clc_alias
        elif v2_api_username and v2_api_passwd:
            self.clc.v2.SetCredentials(
                api_username=v2_api_username,
                api_passwd=v2_api_passwd)
        else:
            return self.module.fail_json(
                msg="You must set the CLC_V2_API_USERNAME and CLC_V2_API_PASSWD "
                    "environment variables")

    def _get_policies_for_datacenter(self, p):
        """
        Get the Policies for a datacenter by calling the CLC API.
        :param p: datacenter to get policies from
        :return: policies in the datacenter
        """
        response = {}

        policies = self.clc.v2.AntiAffinity.GetAll(location=p['location'])

        for policy in policies:
            response[policy.name] = policy
        return response

    def _create_policy(self, p):
        """
        Create an Anti Affinity Policy using the CLC API.
        :param p: datacenter to create policy in
        :return: response dictionary from the CLC API.
        """
        try:
            return self.clc.v2.AntiAffinity.Create(
                name=p['name'],
                location=p['location'])
        except CLCException as ex:
            self.module.fail_json(msg='Failed to create anti affinity policy : {0}. {1}'.format(
                p['name'], ex.response_text
            ))

    def _delete_policy(self, p):
        """
        Delete an Anti Affinity Policy using the CLC API.
        :param p: datacenter to delete a policy from
        :return: none
        """
        try:
            policy = self.policy_dict[p['name']]
            policy.Delete()
        except CLCException as ex:
            self.module.fail_json(msg='Failed to delete anti affinity policy : {0}. {1}'.format(
                p['name'], ex.response_text
            ))

    def _policy_exists(self, policy_name):
        """
        Check to see if an Anti Affinity Policy exists
        :param policy_name: name of the policy
        :return: boolean of if the policy exists
        """
        if policy_name in self.policy_dict:
            return self.policy_dict.get(policy_name)

        return False

    def _ensure_policy_is_absent(self, p):
        """
        Makes sure that a policy is absent
        :param p: dictionary of policy name
        :return: tuple of if a deletion occurred and the name of the policy that was deleted
        """
        changed = False
        if self._policy_exists(policy_name=p['name']):
            changed = True
            if not self.module.check_mode:
                self._delete_policy(p)
        return changed, None

    def _ensure_policy_is_present(self, p):
        """
        Ensures that a policy is present
        :param p: dictionary of a policy name
        :return: tuple of if an addition occurred and the name of the policy that was added
        """
        changed = False
        policy = self._policy_exists(policy_name=p['name'])
        if not policy:
            changed = True
            policy = None
            if not self.module.check_mode:
                policy = self._create_policy(p)
        return changed, policy

    @staticmethod
    def _set_user_agent(clc):
        if hasattr(clc, 'SetRequestsSession'):
            agent_string = "ClcAnsibleModule/" + __version__
            ses = requests.Session()
            ses.headers.update({"Api-Client": agent_string})
            ses.headers['User-Agent'] += " " + agent_string
            clc.SetRequestsSession(ses)


def main():
    """
    The main function.  Instantiates the module and calls process_request.
    :return: none
    """
    module = AnsibleModule(
        argument_spec=ClcAntiAffinityPolicy._define_module_argument_spec(),
        supports_check_mode=True)
    clc_aa_policy = ClcAntiAffinityPolicy(module)
    clc_aa_policy.process_request()

if __name__ == '__main__':
    main()
