#!/usr/bin/python
# 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/>.

DOCUMENTATION = """
---
module: ec2_asg
short_description: Create or delete AWS Autoscaling Groups
description:
  - Can create or delete AWS Autoscaling Groups
  - Works with the ec2_lc module to manage Launch Configurations
version_added: "1.6"
requirements: [ "boto" ]
author: Gareth Rushgrove
options:
  state:
    description:
      - register or deregister the instance
    required: true
    choices: ['present', 'absent']
  group:
    description:
      - Unique name for group to be created or deleted
    required: true
  load_balancers:
    description:
      - List of ELB names to use for the group
    required: true
  availability_zones:
    description:
      - List of availability zone names in which to create the group.
    required: true
  launch_config_name:
    description:
      - Name of the Launch configuration to use for the group. See the ec2_lc module for managing these.
    required: true
  min_size:
    description:
      - Minimum number of instances in group
    required: true
  max_size:
    description:
      - Maximum number of instances in group
    required: true
  aws_secret_key:
    description:
      - AWS secret key. If not set then the value of the AWS_SECRET_KEY environment variable is used.
    required: false
    default: None
    aliases: ['ec2_secret_key', 'secret_key' ]
  aws_access_key:
    description:
      - AWS access key. If not set then the value of the AWS_ACCESS_KEY environment variable is used.
    required: false
    default: None
    aliases: ['ec2_access_key', 'access_key' ]
  region:
    description:
      - The AWS region to use. If not specified then the value of the EC2_REGION environment variable, if any, is used.
    required: false
    aliases: ['aws_region', 'ec2_region']
"""

EXAMPLES = '''
- ec2_asg: >
    group_name: special
    load_balancers: 'lb1,lb2'
    availability_zones: 'eu-west-1a,eu-west-1b'
    launch_config_name: 'lc-1'
    min_size: 1
    max_size: 10
'''

import sys
import time

from ansible.module_utils.basic import *
from ansible.module_utils.ec2 import *

try:
    import boto.ec2.autoscale
    from boto.ec2.autoscale import AutoScaleConnection, AutoScalingGroup
    from boto.exception import BotoServerError
except ImportError:
    print "failed=True msg='boto required for this module'"
    sys.exit(1)

AWS_REGIONS = ['ap-northeast-1',
               'ap-southeast-1',
               'ap-southeast-2',
               'eu-west-1',
               'sa-east-1',
               'us-east-1',
               'us-west-1',
               'us-west-2']


def create_autoscaling_group(connection, module):
    group_name = module.params.get('name')
    load_balancers = module.params['load_balancers']
    availability_zones = module.params['availability_zones']
    launch_config_name = module.params.get('launch_config_name')
    min_size = module.params.get('min_size')
    max_size = module.params.get('max_size')

    launch_configs = connection.get_all_launch_configurations(name=[launch_config_name])

    ag = AutoScalingGroup(
        group_name=group_name,
        load_balancers=load_balancers,
        availability_zones=availability_zones,
        launch_config=launch_configs[0],
        min_size=min_size,
        max_size=max_size,
        connection=connection)

    try:
        connection.create_auto_scaling_group(ag)
        module.exit_json(changed=True)
    except BotoServerError, e:
        module.exit_json(changed=False, msg=str(e))


def delete_autoscaling_group(connection, module):
    group_name = module.params.get('name')
    groups = connection.get_all_groups(names=[group_name])
    if groups:
        group = groups[0]
        group.shutdown_instances()

        instances = True
        while instances:
            connection.get_all_groups()
            for group in groups:
                if group.name == group_name:
                    if not group.instances:
                        instances = False
            time.sleep(10)

        group.delete()
        module.exit_json(changed=True)
    else:
        module.exit_json(changed=False)


def main():
    module = AnsibleModule(
        argument_spec = dict(
            name = dict(required=True, type='str'),
            load_balancers = dict(required=True, type='list'),
            availability_zones = dict(required=True, type='list'),
            launch_config_name = dict(required=True, type='str'),
            min_size = dict(required=True, type='int'),
            max_size = dict(required=True, type='int'),
            state = dict(default='present', choices=['present', 'absent']),
            region = dict(aliases=['aws_region', 'ec2_region'], choices=AWS_REGIONS),
            ec2_url = dict(),
            ec2_secret_key = dict(aliases=['aws_secret_key', 'secret_key'], no_log=True),
            ec2_access_key = dict(aliases=['aws_access_key', 'access_key']),
        )
    )

    ec2_url, aws_access_key, aws_secret_key, region = get_ec2_creds(module)

    state = module.params.get('state')

    try:
        connection = boto.ec2.autoscale.connect_to_region(region, aws_access_key_id=aws_access_key, aws_secret_access_key=aws_secret_key)
    except boto.exception.NoAuthHandlerFound, e:
        module.fail_json(msg = str(e))

    if state == 'present':
        create_autoscaling_group(connection, module)
    elif state == 'absent':
        delete_autoscaling_group(connection, module)


main()