#!/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


DOCUMENTATION = '''
---
module: autoscaling_group_info
version_added: 5.0.0
short_description: Gather information about EC2 Auto Scaling Groups (ASGs) in AWS
description:
  - Gather information about EC2 Auto Scaling Groups (ASGs) in AWS.
  - Prior to release 5.0.0 this module was called C(community.aws.ec2_asg_info).
    The usage did not change.
  - This module was originally added to C(community.aws) in release 1.0.0.
author:
  - "Rob White (@wimnat)"
options:
  name:
    description:
      - The prefix or name of the auto scaling group(s) you are searching for.
      - "Note: This is a regular expression match with implicit '^' (beginning of string). Append '$' for a complete name match."
    type: str
    required: false
  tags:
    description:
      - >
        A dictionary/hash of tags in the format { tag1_name: 'tag1_value', tag2_name: 'tag2_value' } to match against the auto scaling
        group(s) you are searching for.
    required: false
    type: dict
extends_documentation_fragment:
  - amazon.aws.aws
  - amazon.aws.ec2
  - amazon.aws.boto3
'''

EXAMPLES = '''
# Note: These examples do not set authentication details, see the AWS Guide for details.

- name: Find all groups
  amazon.aws.autoscaling_group_info:
  register: asgs

- name: Find a group with matching name/prefix
  amazon.aws.autoscaling_group_info:
    name: public-webserver-asg
  register: asgs

- name: Find a group with matching tags
  amazon.aws.autoscaling_group_info:
    tags:
      project: webapp
      env: production
  register: asgs

- name: Find a group with matching name/prefix and tags
  amazon.aws.autoscaling_group_info:
    name: myproject
    tags:
      env: production
  register: asgs

- name: Fail if no groups are found
  amazon.aws.autoscaling_group_info:
    name: public-webserver-asg
  register: asgs
  failed_when: "{{ asgs.results | length == 0 }}"

- name: Fail if more than 1 group is found
  amazon.aws.autoscaling_group_info:
    name: public-webserver-asg
  register: asgs
  failed_when: "{{ asgs.results | length > 1 }}"
'''

RETURN = '''
---
auto_scaling_group_arn:
    description: The Amazon Resource Name of the ASG
    returned: success
    type: str
    sample: "arn:aws:autoscaling:us-west-2:123456789012:autoScalingGroup:10787c52-0bcb-427d-82ba-c8e4b008ed2e:autoScalingGroupName/public-webapp-production-1"
auto_scaling_group_name:
    description: Name of autoscaling group
    returned: success
    type: str
    sample: "public-webapp-production-1"
availability_zones:
    description: List of Availability Zones that are enabled for this ASG.
    returned: success
    type: list
    sample: ["us-west-2a", "us-west-2b", "us-west-2a"]
created_time:
    description: The date and time this ASG was created, in ISO 8601 format.
    returned: success
    type: str
    sample: "2015-11-25T00:05:36.309Z"
default_cooldown:
    description: The default cooldown time in seconds.
    returned: success
    type: int
    sample: 300
desired_capacity:
    description: The number of EC2 instances that should be running in this group.
    returned: success
    type: int
    sample: 3
health_check_period:
    description: Length of time in seconds after a new EC2 instance comes into service that Auto Scaling starts checking its health.
    returned: success
    type: int
    sample: 30
health_check_type:
    description: The service you want the health status from, one of "EC2" or "ELB".
    returned: success
    type: str
    sample: "ELB"
instances:
    description: List of EC2 instances and their status as it relates to the ASG.
    returned: success
    type: list
    sample: [
        {
            "availability_zone": "us-west-2a",
            "health_status": "Healthy",
            "instance_id": "i-es22ad25",
            "launch_configuration_name": "public-webapp-production-1",
            "lifecycle_state": "InService",
            "protected_from_scale_in": "false"
        }
    ]
launch_config_name:
    description: >
      Name of launch configuration associated with the ASG. Same as launch_configuration_name,
      provided for compatibility with M(amazon.aws.autoscaling_group) module.
    returned: success
    type: str
    sample: "public-webapp-production-1"
launch_configuration_name:
    description: Name of launch configuration associated with the ASG.
    returned: success
    type: str
    sample: "public-webapp-production-1"
lifecycle_hooks:
    description: List of lifecycle hooks for the ASG.
    returned: success
    type: list
    sample: [
        {
            "AutoScalingGroupName": "public-webapp-production-1",
            "DefaultResult": "ABANDON",
            "GlobalTimeout": 172800,
            "HeartbeatTimeout": 3600,
            "LifecycleHookName": "instance-launch",
            "LifecycleTransition": "autoscaling:EC2_INSTANCE_LAUNCHING"
        },
        {
            "AutoScalingGroupName": "public-webapp-production-1",
            "DefaultResult": "ABANDON",
            "GlobalTimeout": 172800,
            "HeartbeatTimeout": 3600,
            "LifecycleHookName": "instance-terminate",
            "LifecycleTransition": "autoscaling:EC2_INSTANCE_TERMINATING"
        }
    ]
load_balancer_names:
    description: List of load balancers names attached to the ASG.
    returned: success
    type: list
    sample: ["elb-webapp-prod"]
max_size:
    description: Maximum size of group
    returned: success
    type: int
    sample: 3
min_size:
    description: Minimum size of group
    returned: success
    type: int
    sample: 1
new_instances_protected_from_scale_in:
    description: Whether or not new instances a protected from automatic scaling in.
    returned: success
    type: bool
    sample: "false"
placement_group:
    description: Placement group into which instances are launched, if any.
    returned: success
    type: str
    sample: None
status:
    description: The current state of the group when DeleteAutoScalingGroup is in progress.
    returned: success
    type: str
    sample: None
tags:
    description: List of tags for the ASG, and whether or not each tag propagates to instances at launch.
    returned: success
    type: list
    sample: [
        {
            "key": "Name",
            "value": "public-webapp-production-1",
            "resource_id": "public-webapp-production-1",
            "resource_type": "auto-scaling-group",
            "propagate_at_launch": "true"
        },
        {
            "key": "env",
            "value": "production",
            "resource_id": "public-webapp-production-1",
            "resource_type": "auto-scaling-group",
            "propagate_at_launch": "true"
        }
    ]
target_group_arns:
    description: List of ARNs of the target groups that the ASG populates
    returned: success
    type: list
    sample: [
        "arn:aws:elasticloadbalancing:ap-southeast-2:123456789012:targetgroup/target-group-host-hello/1a2b3c4d5e6f1a2b",
        "arn:aws:elasticloadbalancing:ap-southeast-2:123456789012:targetgroup/target-group-path-world/abcd1234abcd1234"
    ]
target_group_names:
    description: List of names of the target groups that the ASG populates
    returned: success
    type: list
    sample: [
        "target-group-host-hello",
        "target-group-path-world"
    ]
termination_policies:
    description: A list of termination policies for the group.
    returned: success
    type: str
    sample: ["Default"]
'''

import re

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

from ansible.module_utils.common.dict_transformations import camel_dict_to_snake_dict

from ansible_collections.amazon.aws.plugins.module_utils.core import AnsibleAWSModule
from ansible_collections.amazon.aws.plugins.module_utils.core import is_boto3_error_code


def match_asg_tags(tags_to_match, asg):
    for key, value in tags_to_match.items():
        for tag in asg['Tags']:
            if key == tag['Key'] and value == tag['Value']:
                break
        else:
            return False
    return True


def find_asgs(conn, module, name=None, tags=None):
    """
    Args:
        conn (boto3.AutoScaling.Client): Valid Boto3 ASG client.
        name (str): Optional name of the ASG you are looking for.
        tags (dict): Optional dictionary of tags and values to search for.

    Basic Usage:
        >>> name = 'public-webapp-production'
        >>> tags = { 'env': 'production' }
        >>> conn = boto3.client('autoscaling', region_name='us-west-2')
        >>> results = find_asgs(name, conn)

    Returns:
        List
        [
            {
                "auto_scaling_group_arn": (
                    "arn:aws:autoscaling:us-west-2:123456789012:autoScalingGroup:58abc686-9783-4528-b338-3ad6f1cbbbaf:"
                    "autoScalingGroupName/public-webapp-production"
                ),
                "auto_scaling_group_name": "public-webapp-production",
                "availability_zones": ["us-west-2c", "us-west-2b", "us-west-2a"],
                "created_time": "2016-02-02T23:28:42.481000+00:00",
                "default_cooldown": 300,
                "desired_capacity": 2,
                "enabled_metrics": [],
                "health_check_grace_period": 300,
                "health_check_type": "ELB",
                "instances":
                [
                    {
                        "availability_zone": "us-west-2c",
                        "health_status": "Healthy",
                        "instance_id": "i-047a12cb",
                        "launch_configuration_name": "public-webapp-production-1",
                        "lifecycle_state": "InService",
                        "protected_from_scale_in": false
                    },
                    {
                        "availability_zone": "us-west-2a",
                        "health_status": "Healthy",
                        "instance_id": "i-7a29df2c",
                        "launch_configuration_name": "public-webapp-production-1",
                        "lifecycle_state": "InService",
                        "protected_from_scale_in": false
                    }
                ],
                "launch_config_name": "public-webapp-production-1",
                "launch_configuration_name": "public-webapp-production-1",
                "lifecycle_hooks":
                [
                    {
                        "AutoScalingGroupName": "public-webapp-production-1",
                        "DefaultResult": "ABANDON",
                        "GlobalTimeout": 172800,
                        "HeartbeatTimeout": 3600,
                        "LifecycleHookName": "instance-launch",
                        "LifecycleTransition": "autoscaling:EC2_INSTANCE_LAUNCHING"
                    },
                    {
                        "AutoScalingGroupName": "public-webapp-production-1",
                        "DefaultResult": "ABANDON",
                        "GlobalTimeout": 172800,
                        "HeartbeatTimeout": 3600,
                        "LifecycleHookName": "instance-terminate",
                        "LifecycleTransition": "autoscaling:EC2_INSTANCE_TERMINATING"
                    }
                ],
                "load_balancer_names": ["public-webapp-production-lb"],
                "max_size": 4,
                "min_size": 2,
                "new_instances_protected_from_scale_in": false,
                "placement_group": None,
                "status": None,
                "suspended_processes": [],
                "tags":
                [
                    {
                        "key": "Name",
                        "propagate_at_launch": true,
                        "resource_id": "public-webapp-production",
                        "resource_type": "auto-scaling-group",
                        "value": "public-webapp-production"
                    },
                    {
                        "key": "env",
                        "propagate_at_launch": true,
                        "resource_id": "public-webapp-production",
                        "resource_type": "auto-scaling-group",
                        "value": "production"
                    }
                ],
                "target_group_names": [],
                "target_group_arns": [],
                "termination_policies":
                [
                    "Default"
                ],
                "vpc_zone_identifier":
                [
                    "subnet-a1b1c1d1",
                    "subnet-a2b2c2d2",
                    "subnet-a3b3c3d3"
                ]
            }
        ]
    """

    try:
        asgs_paginator = conn.get_paginator('describe_auto_scaling_groups')
        asgs = asgs_paginator.paginate().build_full_result()
    except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
        module.fail_json_aws(e, msg='Failed to describe AutoScalingGroups')

    if not asgs:
        return asgs

    try:
        elbv2 = module.client('elbv2')
    except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError):
        # This is nice to have, not essential
        elbv2 = None
    matched_asgs = []

    if name is not None:
        # if the user didn't specify a name
        name_prog = re.compile(r'^' + name)

    for asg in asgs['AutoScalingGroups']:
        if name:
            matched_name = name_prog.search(asg['AutoScalingGroupName'])
        else:
            matched_name = True

        if tags:
            matched_tags = match_asg_tags(tags, asg)
        else:
            matched_tags = True

        if matched_name and matched_tags:
            asg = camel_dict_to_snake_dict(asg)
            # compatibility with autoscaling_group module
            if 'launch_configuration_name' in asg:
                asg['launch_config_name'] = asg['launch_configuration_name']
            # workaround for https://github.com/ansible/ansible/pull/25015
            if 'target_group_ar_ns' in asg:
                asg['target_group_arns'] = asg['target_group_ar_ns']
                del asg['target_group_ar_ns']
            if asg.get('target_group_arns'):
                if elbv2:
                    try:
                        tg_paginator = elbv2.get_paginator("describe_target_groups")
                        # Limit of 20 similar to https://docs.aws.amazon.com/elasticloadbalancing/latest/APIReference/API_DescribeLoadBalancers.html
                        tg_chunk_size = 20
                        asg["target_group_names"] = []
                        tg_chunks = [
                            asg["target_group_arns"][i: i + tg_chunk_size]
                            for i in range(0, len(asg["target_group_arns"]), tg_chunk_size)
                        ]
                        for chunk in tg_chunks:
                            tg_result = tg_paginator.paginate(TargetGroupArns=chunk).build_full_result()
                            asg["target_group_names"].extend(
                                [tg["TargetGroupName"] for tg in tg_result["TargetGroups"]]
                            )
                    except is_boto3_error_code("TargetGroupNotFound"):
                        asg["target_group_names"] = []
                    except (
                        botocore.exceptions.ClientError,
                        botocore.exceptions.BotoCoreError,
                    ) as e:  # pylint: disable=duplicate-except
                        module.fail_json_aws(e, msg="Failed to describe Target Groups")
            else:
                asg['target_group_names'] = []
            # get asg lifecycle hooks if any
            try:
                asg_lifecyclehooks = conn.describe_lifecycle_hooks(AutoScalingGroupName=asg['auto_scaling_group_name'])
                asg['lifecycle_hooks'] = asg_lifecyclehooks['LifecycleHooks']
            except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
                module.fail_json_aws(e, msg="Failed to fetch information about ASG lifecycle hooks")
            matched_asgs.append(asg)

    return matched_asgs


def main():

    argument_spec = dict(
        name=dict(type='str'),
        tags=dict(type='dict'),
    )

    module = AnsibleAWSModule(
        argument_spec=argument_spec,
        supports_check_mode=True,
    )

    asg_name = module.params.get('name')
    asg_tags = module.params.get('tags')

    autoscaling = module.client('autoscaling')

    results = find_asgs(autoscaling, module, name=asg_name, tags=asg_tags)
    module.exit_json(results=results)


if __name__ == '__main__':
    main()