#!/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: cloudformation
short_description: create a AWS CloudFormation stack
description:
     - Launches an AWS CloudFormation stack and waits for it complete.
version_added: "1.1"
options:
  stack_name:
    description:
      - name of the cloudformation stack
    required: true
    default: null
    aliases: []
  disable_rollback:
    description:
      - If a stacks fails to form, rollback will remove the stack
    required: false
    default: "no"
    choices: [ "yes", "no" ]
    aliases: []
  template_parameters:
    description:
      - a list of hashes of all the template variables for the stack
    required: true
    default: null
    aliases: []
  region:
    description:
      - The AWS region the stack will be launched in
    required: true
    default: null
    aliases: []
  state:
    description:
      - If state is "present", stack will be created.  If state is "present" and if stack exists and template has changed, it will be updated.
        If state is absent, stack will be removed.
    required: true
    default: null
    aliases: []
  template:
    description:
      - the path of the cloudformation template
    required: true
    default: null
    aliases: []
  wait_for:
    description:
      - Wait while the stack is being created/updated/deleted.
    required: false
    default: "yes"
    choices: [ "yes", "no" ]
    aliases: []

examples:

  tasks:
  - name: launch ansible cloudformation example
    cloudformation: >
      stack_name="ansible-cloudformation" state=present
      region=us-east-1 disable_rollback=yes
      template=files/cloudformation-example.json
    args:
      template_parameters:
        KeyName: jmartin
        DiskType: ephemeral
        InstanceType: m1.small
        ClusterSize: 3

requirements: [ "boto" ]
author: James S. Martin
'''

import boto.cloudformation.connection
import json


class Region:
    def __init__(self, region):
        self.name = region
        self.endpoint = 'cloudformation.%s.amazonaws.com' % region


def boto_exception(err):

        if hasattr(err, 'error_message'):
            error = err.error_message
        elif hasattr(err, 'message'):
            error = err.message
        else:
            error = '%s: %s' % (Exception, err)
        try:
            error_msg = json.loads(error)
        except:
            error_msg = {'Error': error}
        return error_msg


def stack_operation(cfn, stack_name, operation):
    existed = []
    result = {}
    operation_complete = False
    while operation_complete == False:
        try:
            stack = cfn.describe_stacks(stack_name)[0]
            existed.append('yes')
        except:
            if 'yes' in existed:
                result = {'changed': True, 'output': 'Stack Deleted'}
                result['events'] = map(str, list(stack.describe_events()))
            else:
                result = {'changed': True, 'output': 'Stack Not Found'}
            break
        if '%s_COMPLETE' % operation == stack.stack_status:
            result['changed'] = True
            result['events'] = map(str, list(stack.describe_events()))
            result['output'] = 'Stack %s complete' % operation
            break
        elif '%s_FAILED' % operation == stack.stack_status:
            result['changed'] = False
            result['events'] = map(str, list(stack.describe_events()))
            result['output'] = 'Stack %s failed' % operation
            break
        else:
            time.sleep(5)
    return result


def main():
    module = AnsibleModule(
        argument_spec=dict(
            stack_name=dict(required=True),
            template_parameters=dict(required=False),
            region=dict(required=True,
                        choices=['ap-northeast-1', 'ap-southeast-1',
                                 'ap-southeast-2', 'eu-west-1',
                                 'sa-east-1', 'us-east-1', 'us-west-1',
                                 'us-west-2']),
            state=dict(default='present', choices=['present', 'absent']),
            template=dict(default=None, required=True),
            disable_rollback=dict(default=False),
            wait_for=dict(default=True)
        )
    )

    wait_for = module.params['wait_for']
    state = module.params['state']
    stack_name = module.params['stack_name']
    region = Region(module.params['region'])
    template_body = open(module.params['template'], 'r').read()
    disable_rollback = module.params['disable_rollback']
    template_parameters = module.params['template_parameters']

    template_parameters_tup = [(k, v) for k, v in template_parameters.items()]
    stack_outputs = {}
    stack_outputs[module.params['region']] = {}
    stack_outputs[module.params['region']][stack_name] = {}

    try:
        cfn = boto.cloudformation.connection.CloudFormationConnection(
            region=region)
    except boto.exception.NoAuthHandlerFound, e:
        module.fail_json(msg=str(e))
    update = False
    stack_events = []
    result = {}
    operation = None
    output = ''

    if state == 'present':
        try:
            cfn.create_stack(stack_name, parameters=template_parameters_tup,
                             template_body=template_body,
                             disable_rollback=disable_rollback,
                             capabilities=['CAPABILITY_IAM'])
            operation = 'CREATE'
        except Exception, err:
            error_msg = boto_exception(err)
            if error_msg['Error']['Code'] == 'AlreadyExistsException':
                update = True
            else:
                result = {'changed': False, 'output': error_msg}
                module.fail_json(**result)
        if not update:
            result = stack_operation(cfn, stack_name, operation)
    if update:
        try:
            cfn.update_stack(stack_name, parameters=template_parameters_tup,
                             template_body=template_body,
                             disable_rollback=disable_rollback,
                             capabilities=['CAPABILITY_IAM'])
            operation = 'UPDATE'
        except Exception, err:
            error_msg = boto_exception(err)
            if error_msg['Error']['Message'] == 'No updates are to be performed.':
                output = error_msg['Error']['Message']
            result = {'changed': False, 'output': output}
        if operation == 'UPDATE':
            result = stack_operation(cfn, stack_name, operation)

    if state == 'present' or update:
        stack = cfn.describe_stacks(stack_name)[0]
        for output in stack.outputs:
            stack_outputs[module.params['region']][stack_name][
                output.key] = output.value
        result['stack_outputs'] = stack_outputs

# absent state is different because of the way delete_stack works.
# problem is it it doesn't give an error if stack isn't found
# so must describe the stack first

    if state == 'absent':
        try:
            cfn.describe_stacks(stack_name)
            operation = 'DELETE'
        except Exception, err:
            error_msg = boto_exception(err)
            result = {'changed': False, 'output': error_msg}
            module.fail_json(result)
        if operation == 'DELETE':
            cfn.delete_stack(stack_name)
            result = stack_operation(cfn, stack_name, operation)

    module.exit_json(**result)

# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>

main()