#!/usr/bin/python
# Copyright: Ansible Project
# 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: iam_role_facts
short_description: Gather information on IAM roles
description:
    - Gathers information about IAM roles
version_added: "2.5"
requirements: [ boto3 ]
author:
    - "Will Thames (@willthames)"
options:
    name:
        description:
            - Name of a role to search for
            - Mutually exclusive with C(prefix)
        required: false
        default: None
        aliases:
            - role_name
    path_prefix:
        description:
            - Prefix of role I(path) to restrict IAM role search for
            - Mutually exclusive with C(name)
        required: false
        default: None
extends_documentation_fragment:
    - aws
'''

EXAMPLES = '''
# find all existing IAM roles
- iam_role_facts:
  register: result

# describe a single role
- iam_role_facts:
    name: MyIAMRole

# describe all roles matching a path prefix
- iam_role_facts:
    path_prefix: /application/path
'''

RETURN = '''
iam_roles:
  description: List of IAM roles
  returned: always
  type: complex
  contains:
    arn:
      description: Amazon Resource Name for IAM role
      returned: always
      type: string
      sample: arn:aws:iam::123456789012:role/AnsibleTestRole
    assume_role_policy_document:
      description: Policy Document describing what can assume the role
      returned: always
      type: string
    create_date:
      description: Date IAM role was created
      returned: always
      type: string
      sample: '2017-10-23T00:05:08+00:00'
    inline_policies:
      description: List of names of inline policies
      returned: always
      type: list
      sample: []
    managed_policies:
      description: List of attached managed policies
      returned: always
      type: complex
      contains:
        policy_arn:
          description: Amazon Resource Name for the policy
          returned: always
          type: string
          sample: arn:aws:iam::123456789012:policy/AnsibleTestEC2Policy
        policy_name:
          description: Name of managed policy
          returned: always
          type: string
          sample: AnsibleTestEC2Policy
    path:
      description: Path of role
      returned: always
      type: string
      sample: /
    role_id:
      description: Amazon Identifier for the role
      returned: always
      type: string
      sample: AROAII7ABCD123456EFGH
    role_name:
      description: Name of the role
      returned: always
      type: string
      sample: AnsibleTestRole
'''

try:
    import botocore
except ImportError:
    pass  # caught by AnsibleAWSModule

from ansible.module_utils.aws.core import AnsibleAWSModule
from ansible.module_utils.ec2 import boto3_conn, get_aws_connection_info, ec2_argument_spec, AWSRetry
from ansible.module_utils.ec2 import camel_dict_to_snake_dict


@AWSRetry.exponential_backoff()
def list_iam_roles_with_backoff(client, **kwargs):
    paginator = client.get_paginator('list_roles')
    return paginator.paginate(**kwargs).build_full_result()


@AWSRetry.exponential_backoff()
def list_iam_role_policies_with_backoff(client, role_name):
    paginator = client.get_paginator('list_role_policies')
    return paginator.paginate(RoleName=role_name).build_full_result()['PolicyNames']


@AWSRetry.exponential_backoff()
def list_iam_attached_role_policies_with_backoff(client, role_name):
    paginator = client.get_paginator('list_attached_role_policies')
    return paginator.paginate(RoleName=role_name).build_full_result()['AttachedPolicies']


def describe_iam_role(module, client, role):
    name = role['RoleName']
    try:
        role['InlinePolicies'] = list_iam_role_policies_with_backoff(client, name)
    except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
        module.fail_json_aws(e, msg="Couldn't get inline policies for role %s" % name)
    try:
        role['ManagedPolicies'] = list_iam_attached_role_policies_with_backoff(client, name)
    except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
        module.fail_json_aws(e, msg="Couldn't get managed  policies for role %s" % name)
    return role


def describe_iam_roles(module, client):
    name = module.params['name']
    path_prefix = module.params['path_prefix']
    if name:
        try:
            roles = [client.get_role(RoleName=name)['Role']]
        except botocore.exceptions.ClientError as e:
            if e.response['Error']['Code'] == 'NoSuchEntity':
                return []
            else:
                module.fail_json_aws(e, msg="Couldn't get IAM role %s" % name)
        except botocore.exceptions.BotoCoreError as e:
            module.fail_json_aws(e, msg="Couldn't get IAM role %s" % name)
    else:
        params = dict()
        if path_prefix:
            if not path_prefix.startswith('/'):
                path_prefix = '/' + path_prefix
            if not path_prefix.endswith('/'):
                path_prefix = path_prefix + '/'
            params['PathPrefix'] = path_prefix
        try:
            roles = list_iam_roles_with_backoff(client, **params)['Roles']
        except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
            module.fail_json_aws(e, msg="Couldn't list IAM roles")
    return [camel_dict_to_snake_dict(describe_iam_role(module, client, role)) for role in roles]


def main():
    """
     Module action handler
    """
    argument_spec = ec2_argument_spec()
    argument_spec.update(dict(
        name=dict(aliases=['role_name']),
        path_prefix=dict(),
    ))

    module = AnsibleAWSModule(argument_spec=argument_spec,
                              supports_check_mode=True,
                              mutually_exclusive=[['name', 'path_prefix']])

    region, ec2_url, aws_connect_params = get_aws_connection_info(module, boto3=True)
    client = boto3_conn(module, conn_type='client', resource='iam',
                        region=region, endpoint=ec2_url, **aws_connect_params)

    module.exit_json(changed=False, iam_roles=describe_iam_roles(module, client))


if __name__ == '__main__':
    main()