# This code is part of Ansible, but is an independent component.
# This particular file snippet, and this file snippet only, is BSD licensed.
# Modules you write using this snippet, which is embedded dynamically by Ansible
# still belong to the author of the module, and may assign their own license
# to the complete work.
#
# Copyright (c), Michael DeHaan <michael.dehaan@gmail.com>, 2012-2013
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
#    * Redistributions of source code must retain the above copyright
#      notice, this list of conditions and the following disclaimer.
#    * Redistributions in binary form must reproduce the above copyright notice,
#      this list of conditions and the following disclaimer in the documentation
#      and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
# USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

import os
import re
import sys
import traceback

from ansible.module_utils._text import to_native
from ansible.module_utils._text import to_text
from ansible.module_utils.ansible_release import __version__
from ansible.module_utils.basic import env_fallback
from ansible.module_utils.basic import missing_required_lib
from ansible.module_utils.six import binary_type
from ansible.module_utils.six import string_types
from ansible.module_utils.six import text_type
from ansible.module_utils.six import integer_types
# Used to live here, moved into ansible.module_utils.common.dict_transformations
from ansible.module_utils.common.dict_transformations import _camel_to_snake  # pylint: disable=unused-import
from ansible.module_utils.common.dict_transformations import _snake_to_camel  # pylint: disable=unused-import
from ansible.module_utils.common.dict_transformations import camel_dict_to_snake_dict  # pylint: disable=unused-import
from ansible.module_utils.common.dict_transformations import snake_dict_to_camel_dict  # pylint: disable=unused-import

from .cloud import CloudRetry

BOTO_IMP_ERR = None
try:
    import boto
    import boto.ec2  # boto does weird import stuff
    HAS_BOTO = True
except ImportError:
    BOTO_IMP_ERR = traceback.format_exc()
    HAS_BOTO = False

BOTO3_IMP_ERR = None
try:
    import boto3
    import botocore
    HAS_BOTO3 = True
except ImportError:
    BOTO3_IMP_ERR = traceback.format_exc()
    HAS_BOTO3 = False

try:
    # Although this is to allow Python 3 the ability to use the custom comparison as a key, Python 2.7 also
    # uses this (and it works as expected). Python 2.6 will trigger the ImportError.
    from functools import cmp_to_key
    PY3_COMPARISON = True
except ImportError:
    PY3_COMPARISON = False


class AnsibleAWSError(Exception):
    pass


def _botocore_exception_maybe():
    """
    Allow for boto3 not being installed when using these utils by wrapping
    botocore.exceptions instead of assigning from it directly.
    """
    if HAS_BOTO3:
        return botocore.exceptions.ClientError
    return type(None)


class AWSRetry(CloudRetry):
    base_class = _botocore_exception_maybe()

    @staticmethod
    def status_code_from_exception(error):
        return error.response['Error']['Code']

    @staticmethod
    def found(response_code, catch_extra_error_codes=None):
        # This list of failures is based on this API Reference
        # http://docs.aws.amazon.com/AWSEC2/latest/APIReference/errors-overview.html
        #
        # TooManyRequestsException comes from inside botocore when it
        # does retrys, unfortunately however it does not try long
        # enough to allow some services such as API Gateway to
        # complete configuration.  At the moment of writing there is a
        # botocore/boto3 bug open to fix this.
        #
        # https://github.com/boto/boto3/issues/876 (and linked PRs etc)
        retry_on = [
            'RequestLimitExceeded', 'Unavailable', 'ServiceUnavailable',
            'InternalFailure', 'InternalError', 'TooManyRequestsException',
            'Throttling'
        ]
        if catch_extra_error_codes:
            retry_on.extend(catch_extra_error_codes)

        return response_code in retry_on


def boto3_conn(module, conn_type=None, resource=None, region=None, endpoint=None, **params):
    try:
        return _boto3_conn(conn_type=conn_type, resource=resource, region=region, endpoint=endpoint, **params)
    except ValueError as e:
        module.fail_json(msg="Couldn't connect to AWS: %s" % to_native(e))
    except (botocore.exceptions.ProfileNotFound, botocore.exceptions.PartialCredentialsError,
            botocore.exceptions.NoCredentialsError, botocore.exceptions.ConfigParseError) as e:
        module.fail_json(msg=to_native(e))
    except botocore.exceptions.NoRegionError as e:
        module.fail_json(msg="The %s module requires a region and none was found in configuration, "
                         "environment variables or module parameters" % module._name)


def _boto3_conn(conn_type=None, resource=None, region=None, endpoint=None, **params):
    profile = params.pop('profile_name', None)

    if conn_type not in ['both', 'resource', 'client']:
        raise ValueError('There is an issue in the calling code. You '
                         'must specify either both, resource, or client to '
                         'the conn_type parameter in the boto3_conn function '
                         'call')

    config = botocore.config.Config(
        user_agent_extra='Ansible/{0}'.format(__version__),
    )

    if params.get('config') is not None:
        config = config.merge(params.pop('config'))
    if params.get('aws_config') is not None:
        config = config.merge(params.pop('aws_config'))

    session = boto3.session.Session(
        profile_name=profile,
    )

    if conn_type == 'resource':
        return session.resource(resource, config=config, region_name=region, endpoint_url=endpoint, **params)
    elif conn_type == 'client':
        return session.client(resource, config=config, region_name=region, endpoint_url=endpoint, **params)
    else:
        client = session.client(resource, region_name=region, endpoint_url=endpoint, **params)
        resource = session.resource(resource, region_name=region, endpoint_url=endpoint, **params)
        return client, resource


boto3_inventory_conn = _boto3_conn


def boto_exception(err):
    """
    Extracts the error message from a boto exception.

    :param err: Exception from boto
    :return: Error message
    """
    if hasattr(err, 'error_message'):
        error = err.error_message
    elif hasattr(err, 'message'):
        error = str(err.message) + ' ' + str(err) + ' - ' + str(type(err))
    else:
        error = '%s: %s' % (Exception, err)

    return error


def aws_common_argument_spec():
    return dict(
        debug_botocore_endpoint_logs=dict(fallback=(env_fallback, ['ANSIBLE_DEBUG_BOTOCORE_LOGS']), default=False, type='bool'),
        ec2_url=dict(aliases=['aws_endpoint_url', 'endpoint_url']),
        aws_access_key=dict(aliases=['ec2_access_key', 'access_key'], no_log=False),
        aws_secret_key=dict(aliases=['ec2_secret_key', 'secret_key'], no_log=True),
        security_token=dict(aliases=['access_token', 'aws_security_token'], no_log=True),
        validate_certs=dict(default=True, type='bool'),
        aws_ca_bundle=dict(type='path'),
        profile=dict(aliases=['aws_profile']),
        aws_config=dict(type='dict'),
    )


def ec2_argument_spec():
    spec = aws_common_argument_spec()
    spec.update(
        dict(
            region=dict(aliases=['aws_region', 'ec2_region']),
        )
    )
    return spec


def get_aws_region(module, boto3=False):
    region = module.params.get('region')

    if region:
        return region

    if 'AWS_REGION' in os.environ:
        return os.environ['AWS_REGION']
    if 'AWS_DEFAULT_REGION' in os.environ:
        return os.environ['AWS_DEFAULT_REGION']
    if 'EC2_REGION' in os.environ:
        return os.environ['EC2_REGION']

    if not boto3:
        if not HAS_BOTO:
            module.fail_json(msg=missing_required_lib('boto'), exception=BOTO_IMP_ERR)
        # boto.config.get returns None if config not found
        region = boto.config.get('Boto', 'aws_region')
        if region:
            return region
        return boto.config.get('Boto', 'ec2_region')

    if not HAS_BOTO3:
        module.fail_json(msg=missing_required_lib('boto3'), exception=BOTO3_IMP_ERR)

    # here we don't need to make an additional call, will default to 'us-east-1' if the below evaluates to None.
    try:
        profile_name = module.params.get('profile')
        return botocore.session.Session(profile=profile_name).get_config_variable('region')
    except botocore.exceptions.ProfileNotFound as e:
        return None


def get_aws_connection_info(module, boto3=False):

    # Check module args for credentials, then check environment vars
    # access_key

    ec2_url = module.params.get('ec2_url')
    access_key = module.params.get('aws_access_key')
    secret_key = module.params.get('aws_secret_key')
    security_token = module.params.get('security_token')
    region = get_aws_region(module, boto3)
    profile_name = module.params.get('profile')
    validate_certs = module.params.get('validate_certs')
    ca_bundle = module.params.get('aws_ca_bundle')
    config = module.params.get('aws_config')

    # Only read the profile environment variables if we've *not* been passed
    # any credentials as parameters.
    if not profile_name and not access_key and not secret_key:
        if os.environ.get('AWS_PROFILE'):
            profile_name = os.environ.get('AWS_PROFILE')
        if os.environ.get('AWS_DEFAULT_PROFILE'):
            profile_name = os.environ.get('AWS_DEFAULT_PROFILE')

    if profile_name and (access_key or secret_key or security_token):
        module.deprecate("Passing both a profile and access tokens has been deprecated."
                         "  Only the profile will be used."
                         "  In later versions of Ansible the options will be mutually exclusive",
                         date='2022-06-01', collection_name='amazon.aws')

    if not ec2_url:
        if 'AWS_URL' in os.environ:
            ec2_url = os.environ['AWS_URL']
        elif 'EC2_URL' in os.environ:
            ec2_url = os.environ['EC2_URL']

    if not access_key:
        if os.environ.get('AWS_ACCESS_KEY_ID'):
            access_key = os.environ['AWS_ACCESS_KEY_ID']
        elif os.environ.get('AWS_ACCESS_KEY'):
            access_key = os.environ['AWS_ACCESS_KEY']
        elif os.environ.get('EC2_ACCESS_KEY'):
            access_key = os.environ['EC2_ACCESS_KEY']
        elif HAS_BOTO and boto.config.get('Credentials', 'aws_access_key_id'):
            access_key = boto.config.get('Credentials', 'aws_access_key_id')
        elif HAS_BOTO and boto.config.get('default', 'aws_access_key_id'):
            access_key = boto.config.get('default', 'aws_access_key_id')
        else:
            # in case access_key came in as empty string
            access_key = None

    if not secret_key:
        if os.environ.get('AWS_SECRET_ACCESS_KEY'):
            secret_key = os.environ['AWS_SECRET_ACCESS_KEY']
        elif os.environ.get('AWS_SECRET_KEY'):
            secret_key = os.environ['AWS_SECRET_KEY']
        elif os.environ.get('EC2_SECRET_KEY'):
            secret_key = os.environ['EC2_SECRET_KEY']
        elif HAS_BOTO and boto.config.get('Credentials', 'aws_secret_access_key'):
            secret_key = boto.config.get('Credentials', 'aws_secret_access_key')
        elif HAS_BOTO and boto.config.get('default', 'aws_secret_access_key'):
            secret_key = boto.config.get('default', 'aws_secret_access_key')
        else:
            # in case secret_key came in as empty string
            secret_key = None

    if not security_token:
        if os.environ.get('AWS_SECURITY_TOKEN'):
            security_token = os.environ['AWS_SECURITY_TOKEN']
        elif os.environ.get('AWS_SESSION_TOKEN'):
            security_token = os.environ['AWS_SESSION_TOKEN']
        elif os.environ.get('EC2_SECURITY_TOKEN'):
            security_token = os.environ['EC2_SECURITY_TOKEN']
        elif HAS_BOTO and boto.config.get('Credentials', 'aws_security_token'):
            security_token = boto.config.get('Credentials', 'aws_security_token')
        elif HAS_BOTO and boto.config.get('default', 'aws_security_token'):
            security_token = boto.config.get('default', 'aws_security_token')
        else:
            # in case secret_token came in as empty string
            security_token = None

    if not ca_bundle:
        if os.environ.get('AWS_CA_BUNDLE'):
            ca_bundle = os.environ.get('AWS_CA_BUNDLE')

    if HAS_BOTO3 and boto3:
        boto_params = dict(aws_access_key_id=access_key,
                           aws_secret_access_key=secret_key,
                           aws_session_token=security_token)

        if profile_name:
            boto_params = dict(aws_access_key_id=None, aws_secret_access_key=None, aws_session_token=None)
            boto_params['profile_name'] = profile_name

        if validate_certs and ca_bundle:
            boto_params['verify'] = ca_bundle
        else:
            boto_params['verify'] = validate_certs

    else:
        boto_params = dict(aws_access_key_id=access_key,
                           aws_secret_access_key=secret_key,
                           security_token=security_token)

        # only set profile_name if passed as an argument
        if profile_name:
            boto_params['profile_name'] = profile_name

        boto_params['validate_certs'] = validate_certs

    if config is not None:
        if HAS_BOTO3 and boto3:
            boto_params['aws_config'] = botocore.config.Config(**config)
        elif HAS_BOTO and not boto3:
            if 'user_agent' in config:
                sys.modules["boto.connection"].UserAgent = config['user_agent']

    for param, value in boto_params.items():
        if isinstance(value, binary_type):
            boto_params[param] = text_type(value, 'utf-8', 'strict')

    return region, ec2_url, boto_params


def get_ec2_creds(module):
    ''' for compatibility mode with old modules that don't/can't yet
        use ec2_connect method '''
    region, ec2_url, boto_params = get_aws_connection_info(module)
    return ec2_url, boto_params['aws_access_key_id'], boto_params['aws_secret_access_key'], region


def boto_fix_security_token_in_profile(conn, profile_name):
    ''' monkey patch for boto issue boto/boto#2100 '''
    profile = 'profile ' + profile_name
    if boto.config.has_option(profile, 'aws_security_token'):
        conn.provider.set_security_token(boto.config.get(profile, 'aws_security_token'))
    return conn


def connect_to_aws(aws_module, region, **params):
    try:
        conn = aws_module.connect_to_region(region, **params)
    except(boto.provider.ProfileNotFoundError):
        raise AnsibleAWSError("Profile given for AWS was not found.  Please fix and retry.")
    if not conn:
        if region not in [aws_module_region.name for aws_module_region in aws_module.regions()]:
            raise AnsibleAWSError("Region %s does not seem to be available for aws module %s. If the region definitely exists, you may need to upgrade "
                                  "boto or extend with endpoints_path" % (region, aws_module.__name__))
        else:
            raise AnsibleAWSError("Unknown problem connecting to region %s for aws module %s." % (region, aws_module.__name__))
    if params.get('profile_name'):
        conn = boto_fix_security_token_in_profile(conn, params['profile_name'])
    return conn


def ec2_connect(module):

    """ Return an ec2 connection"""

    region, ec2_url, boto_params = get_aws_connection_info(module)

    # If ec2_url is present use it
    if ec2_url:
        try:
            ec2 = boto.connect_ec2_endpoint(ec2_url, **boto_params)
        except (boto.exception.NoAuthHandlerFound, AnsibleAWSError, boto.provider.ProfileNotFoundError) as e:
            module.fail_json(msg=str(e))
    # Otherwise, if we have a region specified, connect to its endpoint.
    elif region:
        try:
            ec2 = connect_to_aws(boto.ec2, region, **boto_params)
        except (boto.exception.NoAuthHandlerFound, AnsibleAWSError, boto.provider.ProfileNotFoundError) as e:
            module.fail_json(msg=str(e))
    else:
        module.fail_json(msg="Either region or ec2_url must be specified")

    return ec2


def ansible_dict_to_boto3_filter_list(filters_dict):

    """ Convert an Ansible dict of filters to list of dicts that boto3 can use
    Args:
        filters_dict (dict): Dict of AWS filters.
    Basic Usage:
        >>> filters = {'some-aws-id': 'i-01234567'}
        >>> ansible_dict_to_boto3_filter_list(filters)
        {
            'some-aws-id': 'i-01234567'
        }
    Returns:
        List: List of AWS filters and their values
        [
            {
                'Name': 'some-aws-id',
                'Values': [
                    'i-01234567',
                ]
            }
        ]
    """

    filters_list = []
    for k, v in filters_dict.items():
        filter_dict = {'Name': k}
        if isinstance(v, bool):
            filter_dict['Values'] = [str(v).lower()]
        elif isinstance(v, integer_types):
            filter_dict['Values'] = [str(v)]
        elif isinstance(v, string_types):
            filter_dict['Values'] = [v]
        else:
            filter_dict['Values'] = v

        filters_list.append(filter_dict)

    return filters_list


def boto3_tag_list_to_ansible_dict(tags_list, tag_name_key_name=None, tag_value_key_name=None):

    """ Convert a boto3 list of resource tags to a flat dict of key:value pairs
    Args:
        tags_list (list): List of dicts representing AWS tags.
        tag_name_key_name (str): Value to use as the key for all tag keys (useful because boto3 doesn't always use "Key")
        tag_value_key_name (str): Value to use as the key for all tag values (useful because boto3 doesn't always use "Value")
    Basic Usage:
        >>> tags_list = [{'Key': 'MyTagKey', 'Value': 'MyTagValue'}]
        >>> boto3_tag_list_to_ansible_dict(tags_list)
        [
            {
                'Key': 'MyTagKey',
                'Value': 'MyTagValue'
            }
        ]
    Returns:
        Dict: Dict of key:value pairs representing AWS tags
         {
            'MyTagKey': 'MyTagValue',
        }
    """

    if tag_name_key_name and tag_value_key_name:
        tag_candidates = {tag_name_key_name: tag_value_key_name}
    else:
        tag_candidates = {'key': 'value', 'Key': 'Value'}

    # minio seems to return [{}] as an empty tags_list
    if not tags_list or not any(tag for tag in tags_list):
        return {}
    for k, v in tag_candidates.items():
        if k in tags_list[0] and v in tags_list[0]:
            return dict((tag[k], tag[v]) for tag in tags_list)
    raise ValueError("Couldn't find tag key (candidates %s) in tag list %s" % (str(tag_candidates), str(tags_list)))


def ansible_dict_to_boto3_tag_list(tags_dict, tag_name_key_name='Key', tag_value_key_name='Value'):

    """ Convert a flat dict of key:value pairs representing AWS resource tags to a boto3 list of dicts
    Args:
        tags_dict (dict): Dict representing AWS resource tags.
        tag_name_key_name (str): Value to use as the key for all tag keys (useful because boto3 doesn't always use "Key")
        tag_value_key_name (str): Value to use as the key for all tag values (useful because boto3 doesn't always use "Value")
    Basic Usage:
        >>> tags_dict = {'MyTagKey': 'MyTagValue'}
        >>> ansible_dict_to_boto3_tag_list(tags_dict)
        {
            'MyTagKey': 'MyTagValue'
        }
    Returns:
        List: List of dicts containing tag keys and values
        [
            {
                'Key': 'MyTagKey',
                'Value': 'MyTagValue'
            }
        ]
    """

    tags_list = []
    for k, v in tags_dict.items():
        tags_list.append({tag_name_key_name: k, tag_value_key_name: to_native(v)})

    return tags_list


def get_ec2_security_group_ids_from_names(sec_group_list, ec2_connection, vpc_id=None, boto3=True):

    """ Return list of security group IDs from security group names. Note that security group names are not unique
     across VPCs.  If a name exists across multiple VPCs and no VPC ID is supplied, all matching IDs will be returned. This
     will probably lead to a boto exception if you attempt to assign both IDs to a resource so ensure you wrap the call in
     a try block
     """

    def get_sg_name(sg, boto3):

        if boto3:
            return sg['GroupName']
        else:
            return sg.name

    def get_sg_id(sg, boto3):

        if boto3:
            return sg['GroupId']
        else:
            return sg.id

    sec_group_id_list = []

    if isinstance(sec_group_list, string_types):
        sec_group_list = [sec_group_list]

    # Get all security groups
    if boto3:
        if vpc_id:
            filters = [
                {
                    'Name': 'vpc-id',
                    'Values': [
                        vpc_id,
                    ]
                }
            ]
            all_sec_groups = ec2_connection.describe_security_groups(Filters=filters)['SecurityGroups']
        else:
            all_sec_groups = ec2_connection.describe_security_groups()['SecurityGroups']
    else:
        if vpc_id:
            filters = {'vpc-id': vpc_id}
            all_sec_groups = ec2_connection.get_all_security_groups(filters=filters)
        else:
            all_sec_groups = ec2_connection.get_all_security_groups()

    unmatched = set(sec_group_list).difference(str(get_sg_name(all_sg, boto3)) for all_sg in all_sec_groups)
    sec_group_name_list = list(set(sec_group_list) - set(unmatched))

    if len(unmatched) > 0:
        # If we have unmatched names that look like an ID, assume they are
        sec_group_id_list[:] = [sg for sg in unmatched if re.match('sg-[a-fA-F0-9]+$', sg)]
        still_unmatched = [sg for sg in unmatched if not re.match('sg-[a-fA-F0-9]+$', sg)]
        if len(still_unmatched) > 0:
            raise ValueError("The following group names are not valid: %s" % ', '.join(still_unmatched))

    sec_group_id_list += [str(get_sg_id(all_sg, boto3)) for all_sg in all_sec_groups if str(get_sg_name(all_sg, boto3)) in sec_group_name_list]

    return sec_group_id_list


def _hashable_policy(policy, policy_list):
    """
        Takes a policy and returns a list, the contents of which are all hashable and sorted.
        Example input policy:
        {'Version': '2012-10-17',
         'Statement': [{'Action': 's3:PutObjectAcl',
                        'Sid': 'AddCannedAcl2',
                        'Resource': 'arn:aws:s3:::test_policy/*',
                        'Effect': 'Allow',
                        'Principal': {'AWS': ['arn:aws:iam::XXXXXXXXXXXX:user/username1', 'arn:aws:iam::XXXXXXXXXXXX:user/username2']}
                       }]}
        Returned value:
        [('Statement',  ((('Action', (u's3:PutObjectAcl',)),
                          ('Effect', (u'Allow',)),
                          ('Principal', ('AWS', ((u'arn:aws:iam::XXXXXXXXXXXX:user/username1',), (u'arn:aws:iam::XXXXXXXXXXXX:user/username2',)))),
                          ('Resource', (u'arn:aws:s3:::test_policy/*',)), ('Sid', (u'AddCannedAcl2',)))),
         ('Version', (u'2012-10-17',)))]

    """
    # Amazon will automatically convert bool and int to strings for us
    if isinstance(policy, bool):
        return tuple([str(policy).lower()])
    elif isinstance(policy, int):
        return tuple([str(policy)])

    if isinstance(policy, list):
        for each in policy:
            tupleified = _hashable_policy(each, [])
            if isinstance(tupleified, list):
                tupleified = tuple(tupleified)
            policy_list.append(tupleified)
    elif isinstance(policy, string_types) or isinstance(policy, binary_type):
        policy = to_text(policy)
        # convert root account ARNs to just account IDs
        if policy.startswith('arn:aws:iam::') and policy.endswith(':root'):
            policy = policy.split(':')[4]
        return [policy]
    elif isinstance(policy, dict):
        sorted_keys = list(policy.keys())
        sorted_keys.sort()
        for key in sorted_keys:
            element = policy[key]
            # Special case defined in
            # https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_principal.html
            if key in ["NotPrincipal", "Principal"] and policy[key] == "*":
                element = {"AWS": "*"}
            tupleified = _hashable_policy(element, [])
            if isinstance(tupleified, list):
                tupleified = tuple(tupleified)
            policy_list.append((key, tupleified))

    # ensure we aren't returning deeply nested structures of length 1
    if len(policy_list) == 1 and isinstance(policy_list[0], tuple):
        policy_list = policy_list[0]
    if isinstance(policy_list, list):
        if PY3_COMPARISON:
            policy_list.sort(key=cmp_to_key(py3cmp))
        else:
            policy_list.sort()
    return policy_list


def py3cmp(a, b):
    """ Python 2 can sort lists of mixed types. Strings < tuples. Without this function this fails on Python 3."""
    try:
        if a > b:
            return 1
        elif a < b:
            return -1
        else:
            return 0
    except TypeError as e:
        # check to see if they're tuple-string
        # always say strings are less than tuples (to maintain compatibility with python2)
        str_ind = to_text(e).find('str')
        tup_ind = to_text(e).find('tuple')
        if -1 not in (str_ind, tup_ind):
            if str_ind < tup_ind:
                return -1
            elif tup_ind < str_ind:
                return 1
        raise


def compare_policies(current_policy, new_policy, default_version="2008-10-17"):
    """ Compares the existing policy and the updated policy
        Returns True if there is a difference between policies.
    """
    # https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_version.html
    if default_version:
        if isinstance(current_policy, dict):
            current_policy = current_policy.copy()
            current_policy.setdefault("Version", default_version)
        if isinstance(new_policy, dict):
            new_policy = new_policy.copy()
            new_policy.setdefault("Version", default_version)

    return set(_hashable_policy(new_policy, [])) != set(_hashable_policy(current_policy, []))


def sort_json_policy_dict(policy_dict):

    """ Sort any lists in an IAM JSON policy so that comparison of two policies with identical values but
    different orders will return true
    Args:
        policy_dict (dict): Dict representing IAM JSON policy.
    Basic Usage:
        >>> my_iam_policy = {'Principle': {'AWS':["31","7","14","101"]}
        >>> sort_json_policy_dict(my_iam_policy)
    Returns:
        Dict: Will return a copy of the policy as a Dict but any List will be sorted
        {
            'Principle': {
                'AWS': [ '7', '14', '31', '101' ]
            }
        }
    """

    def value_is_list(my_list):

        checked_list = []
        for item in my_list:
            if isinstance(item, dict):
                checked_list.append(sort_json_policy_dict(item))
            elif isinstance(item, list):
                checked_list.append(value_is_list(item))
            else:
                checked_list.append(item)

        # Sort list. If it's a list of dictionaries, sort by tuple of key-value
        # pairs, since Python 3 doesn't allow comparisons such as `<` between dictionaries.
        checked_list.sort(key=lambda x: sorted(x.items()) if isinstance(x, dict) else x)
        return checked_list

    ordered_policy_dict = {}
    for key, value in policy_dict.items():
        if isinstance(value, dict):
            ordered_policy_dict[key] = sort_json_policy_dict(value)
        elif isinstance(value, list):
            ordered_policy_dict[key] = value_is_list(value)
        else:
            ordered_policy_dict[key] = value

    return ordered_policy_dict


def map_complex_type(complex_type, type_map):
    """
        Allows to cast elements within a dictionary to a specific type
        Example of usage:

        DEPLOYMENT_CONFIGURATION_TYPE_MAP = {
            'maximum_percent': 'int',
            'minimum_healthy_percent': 'int'
        }

        deployment_configuration = map_complex_type(module.params['deployment_configuration'],
                                                    DEPLOYMENT_CONFIGURATION_TYPE_MAP)

        This ensures all keys within the root element are casted and valid integers
    """

    if complex_type is None:
        return
    new_type = type(complex_type)()
    if isinstance(complex_type, dict):
        for key in complex_type:
            if key in type_map:
                if isinstance(type_map[key], list):
                    new_type[key] = map_complex_type(
                        complex_type[key],
                        type_map[key][0])
                else:
                    new_type[key] = map_complex_type(
                        complex_type[key],
                        type_map[key])
            else:
                return complex_type
    elif isinstance(complex_type, list):
        for i in range(len(complex_type)):
            new_type.append(map_complex_type(
                complex_type[i],
                type_map))
    elif type_map:
        return globals()['__builtins__'][type_map](complex_type)
    return new_type


def compare_aws_tags(current_tags_dict, new_tags_dict, purge_tags=True):
    """
    Compare two dicts of AWS tags. Dicts are expected to of been created using 'boto3_tag_list_to_ansible_dict' helper function.
    Two dicts are returned - the first is tags to be set, the second is any tags to remove. Since the AWS APIs differ
    these may not be able to be used out of the box.

    :param current_tags_dict:
    :param new_tags_dict:
    :param purge_tags:
    :return: tag_key_value_pairs_to_set: a dict of key value pairs that need to be set in AWS. If all tags are identical this dict will be empty
    :return: tag_keys_to_unset: a list of key names (type str) that need to be unset in AWS. If no tags need to be unset this list will be empty
    """

    tag_key_value_pairs_to_set = {}
    tag_keys_to_unset = []

    for key in current_tags_dict.keys():
        if key not in new_tags_dict and purge_tags:
            tag_keys_to_unset.append(key)

    for key in set(new_tags_dict.keys()) - set(tag_keys_to_unset):
        if to_text(new_tags_dict[key]) != current_tags_dict.get(key):
            tag_key_value_pairs_to_set[key] = new_tags_dict[key]

    return tag_key_value_pairs_to_set, tag_keys_to_unset


@AWSRetry.jittered_backoff()
def _describe_ec2_tags(client, **params):
    paginator = client.get_paginator('describe_tags')
    return paginator.paginate(**params).build_full_result()


def add_ec2_tags(client, module, resource_id, tags_to_set, retry_codes=None):
    """
    Sets Tags on an EC2 resource.

    :param client: an EC2 boto3 client
    :param module: an AnsibleAWSModule object
    :param resource_id: the identifier for the resource
    :param tags_to_set: A dictionary of key/value pairs to set
    :param retry_codes: additional boto3 error codes to trigger retries
    """

    if not tags_to_set:
        return False
    if module.check_mode:
        return True

    if not retry_codes:
        retry_codes = []

    try:
        tags_to_add = ansible_dict_to_boto3_tag_list(tags_to_set)
        AWSRetry.jittered_backoff(retries=10, catch_extra_error_codes=retry_codes)(
            client.create_tags
        )(
            Resources=[resource_id], Tags=tags_to_add
        )
    except (botocore.exceptions.BotoCoreError, botocore.exceptions.ClientError) as e:
        module.fail_json_aws(e, msg="Unable to add tags {0} to {1}".format(tags_to_set, resource_id))
    return True


def remove_ec2_tags(client, module, resource_id, tags_to_unset, retry_codes=None):
    """
    Removes Tags from an EC2 resource.

    :param client: an EC2 boto3 client
    :param module: an AnsibleAWSModule object
    :param resource_id: the identifier for the resource
    :param tags_to_unset: a list of tag keys to removes
    :param retry_codes: additional boto3 error codes to trigger retries
    """

    if not tags_to_unset:
        return False
    if module.check_mode:
        return True

    if not retry_codes:
        retry_codes = []

    tags_to_remove = [dict(Key=tagkey) for tagkey in tags_to_unset]

    try:
        AWSRetry.jittered_backoff(retries=10, catch_extra_error_codes=retry_codes)(
            client.delete_tags
        )(
            Resources=[resource_id], Tags=tags_to_remove
        )
    except (botocore.exceptions.BotoCoreError, botocore.exceptions.ClientError) as e:
        module.fail_json_aws(e, msg="Unable to delete tags {0} from {1}".format(tags_to_unset, resource_id))
    return True


def describe_ec2_tags(client, module, resource_id, resource_type=None, retry_codes=None):
    """
    Performs a paginated search of EC2 resource tags.

    :param client: an EC2 boto3 client
    :param module: an AnsibleAWSModule object
    :param resource_id: the identifier for the resource
    :param resource_type: the type of the resource
    :param retry_codes: additional boto3 error codes to trigger retries
    """
    filters = {'resource-id': resource_id}
    if resource_type:
        filters['resource-type'] = resource_type
    filters = ansible_dict_to_boto3_filter_list(filters)

    if not retry_codes:
        retry_codes = []

    try:
        results = AWSRetry.jittered_backoff(retries=10, catch_extra_error_codes=retry_codes)(
            _describe_ec2_tags
        )(
            client, Filters=filters
        )
        return boto3_tag_list_to_ansible_dict(results.get('Tags', None))
    except (botocore.exceptions.BotoCoreError, botocore.exceptions.ClientError) as e:
        module.fail_json_aws(e, msg="Failed to describe tags for EC2 Resource: {0}".format(resource_id))


def ensure_ec2_tags(client, module, resource_id, resource_type=None, tags=None, purge_tags=True, retry_codes=None):
    """
    Updates the tags on an EC2 resource.

    To remove all tags the tags parameter must be explicitly set to an empty dictionary.

    :param client: an EC2 boto3 client
    :param module: an AnsibleAWSModule object
    :param resource_id: the identifier for the resource
    :param resource_type: the type of the resource
    :param tags: the Tags to apply to the resource
    :param purge_tags: whether tags missing from the tag list should be removed
    :param retry_codes: additional boto3 error codes to trigger retries
    :return: changed: returns True if the tags are changed
    """

    if tags is None:
        return False

    if not retry_codes:
        retry_codes = []

    changed = False
    current_tags = describe_ec2_tags(client, module, resource_id, resource_type, retry_codes)

    tags_to_set, tags_to_unset = compare_aws_tags(current_tags, tags, purge_tags)

    if purge_tags and not tags:
        tags_to_unset = current_tags

    changed |= remove_ec2_tags(client, module, resource_id, tags_to_unset, retry_codes)
    changed |= add_ec2_tags(client, module, resource_id, tags_to_set, retry_codes)

    return changed
