#!/usr/bin/python
# -*- coding: utf-8 -*-

# Copyright: Ansible Project
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)

DOCUMENTATION = r"""
---
module: efs_info
version_added: 1.0.0
short_description: Get information about Amazon EFS file systems
description:
- This module can be used to search Amazon EFS file systems.
  Note that the M(community.aws.efs_info) module no longer returns C(ansible_facts)!
author:
- "Ryan Sydnor (@ryansydnor)"
options:
    name:
      description:
      - Creation Token of Amazon EFS file system.
      aliases: [ creation_token ]
      type: str
    id:
      description:
      - ID of Amazon EFS.
      type: str
    tags:
      description:
      - List of tags of Amazon EFS. Should be defined as dictionary.
      type: dict
      default: {}
    targets:
      description:
      - List of targets on which to filter the returned results.
      - Result must match all of the specified targets, each of which can be a security group ID, a subnet ID or an IP address.
      type: list
      elements: str
      default: []
extends_documentation_fragment:
- amazon.aws.common.modules
- amazon.aws.region.modules
- amazon.aws.boto3
"""

EXAMPLES = r"""
- name: Find all existing efs
  community.aws.efs_info:
  register: result

- name: Find efs using id
  community.aws.efs_info:
    id: fs-1234abcd
  register: result

- name: Searching all EFS instances with tag Name = 'myTestNameTag', in subnet 'subnet-1a2b3c4d' and with security group 'sg-4d3c2b1a'
  community.aws.efs_info:
    tags:
      Name: myTestNameTag
    targets:
      - subnet-1a2b3c4d
      - sg-4d3c2b1a
  register: result

- ansible.builtin.debug:
    msg: "{{ result['efs'] }}"
"""

RETURN = r"""
creation_time:
    description: timestamp of creation date
    returned: always
    type: str
    sample: "2015-11-16 07:30:57-05:00"
creation_token:
    description: EFS creation token
    returned: always
    type: str
    sample: console-88609e04-9a0e-4a2e-912c-feaa99509961
file_system_id:
    description: ID of the file system
    returned: always
    type: str
    sample: fs-xxxxxxxx
life_cycle_state:
    description: state of the EFS file system
    returned: always
    type: str
    sample: creating, available, deleting, deleted
mount_point:
    description: url of file system with leading dot from the time AWS EFS required to add network suffix to EFS address
    returned: always
    type: str
    sample: .fs-xxxxxxxx.efs.us-west-2.amazonaws.com:/
filesystem_address:
    description: url of file system
    returned: always
    type: str
    sample: fs-xxxxxxxx.efs.us-west-2.amazonaws.com:/
mount_targets:
    description: list of mount targets
    returned: always
    type: list
    sample:
        [
            {
                "file_system_id": "fs-a7ad440e",
                "ip_address": "172.31.17.173",
                "life_cycle_state": "available",
                "mount_target_id": "fsmt-d8907871",
                "network_interface_id": "eni-6e387e26",
                "owner_id": "123456789012",
                "security_groups": [
                    "sg-a30b22c6"
                ],
                "subnet_id": "subnet-e265c895"
            },
            ...
        ]
name:
    description: name of the file system
    returned: always
    type: str
    sample: my-efs
number_of_mount_targets:
    description: the number of targets mounted
    returned: always
    type: int
    sample: 3
owner_id:
    description: AWS account ID of EFS owner
    returned: always
    type: str
    sample: XXXXXXXXXXXX
size_in_bytes:
    description: size of the file system in bytes as of a timestamp
    returned: always
    type: dict
    sample:
        {
            "timestamp": "2015-12-21 13:59:59-05:00",
            "value": 12288
        }
performance_mode:
    description: performance mode of the file system
    returned: always
    type: str
    sample: "generalPurpose"
throughput_mode:
    description: mode of throughput for the file system
    returned: always
    type: str
    sample: "bursting"
provisioned_throughput_in_mibps:
    description: throughput provisioned in Mibps
    returned: when throughput_mode is set to "provisioned"
    type: float
    sample: 15.0
tags:
    description: tags on the efs instance
    returned: always
    type: dict
    sample:
        {
            "name": "my-efs",
            "key": "Value"
        }
"""


from collections import defaultdict

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

from ansible.module_utils._text import to_native
from ansible.module_utils.common.dict_transformations import camel_dict_to_snake_dict

from ansible_collections.amazon.aws.plugins.module_utils.retries import AWSRetry
from ansible_collections.amazon.aws.plugins.module_utils.tagging import boto3_tag_list_to_ansible_dict

from ansible_collections.community.aws.plugins.module_utils.modules import AnsibleCommunityAWSModule as AnsibleAWSModule


class EFSConnection(object):
    STATE_CREATING = "creating"
    STATE_AVAILABLE = "available"
    STATE_DELETING = "deleting"
    STATE_DELETED = "deleted"

    def __init__(self, module):
        try:
            self.connection = module.client("efs")
            self.module = module
        except Exception as e:
            module.fail_json(msg=f"Failed to connect to AWS: {to_native(e)}")

        self.region = module.region

    @AWSRetry.exponential_backoff(catch_extra_error_codes=["ThrottlingException"])
    def list_file_systems(self, **kwargs):
        """
        Returns generator of file systems including all attributes of FS
        """
        paginator = self.connection.get_paginator("describe_file_systems")
        return paginator.paginate(**kwargs).build_full_result()["FileSystems"]

    @AWSRetry.exponential_backoff(catch_extra_error_codes=["ThrottlingException"])
    def get_tags(self, file_system_id):
        """
        Returns tag list for selected instance of EFS
        """
        paginator = self.connection.get_paginator("describe_tags")
        return boto3_tag_list_to_ansible_dict(
            paginator.paginate(FileSystemId=file_system_id).build_full_result()["Tags"]
        )

    @AWSRetry.exponential_backoff(catch_extra_error_codes=["ThrottlingException"])
    def get_mount_targets(self, file_system_id):
        """
        Returns mount targets for selected instance of EFS
        """
        paginator = self.connection.get_paginator("describe_mount_targets")
        return paginator.paginate(FileSystemId=file_system_id).build_full_result()["MountTargets"]

    @AWSRetry.jittered_backoff(catch_extra_error_codes=["ThrottlingException"])
    def get_security_groups(self, mount_target_id):
        """
        Returns security groups for selected instance of EFS
        """
        return self.connection.describe_mount_target_security_groups(MountTargetId=mount_target_id)["SecurityGroups"]

    def get_mount_targets_data(self, file_systems):
        for item in file_systems:
            if item["life_cycle_state"] == self.STATE_AVAILABLE:
                try:
                    mount_targets = self.get_mount_targets(item["file_system_id"])
                except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
                    self.module.fail_json_aws(e, msg="Couldn't get EFS targets")
                for mt in mount_targets:
                    item["mount_targets"].append(camel_dict_to_snake_dict(mt))
        return file_systems

    def get_security_groups_data(self, file_systems):
        for item in file_systems:
            if item["life_cycle_state"] == self.STATE_AVAILABLE:
                for target in item["mount_targets"]:
                    if target["life_cycle_state"] == self.STATE_AVAILABLE:
                        try:
                            target["security_groups"] = self.get_security_groups(target["mount_target_id"])
                        except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
                            self.module.fail_json_aws(e, msg="Couldn't get EFS security groups")
                    else:
                        target["security_groups"] = []
            else:
                item["tags"] = {}
                item["mount_targets"] = []
        return file_systems

    def get_file_systems(self, file_system_id=None, creation_token=None):
        kwargs = dict()
        if file_system_id:
            kwargs["FileSystemId"] = file_system_id
        if creation_token:
            kwargs["CreationToken"] = creation_token
        try:
            file_systems = self.list_file_systems(**kwargs)
        except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
            self.module.fail_json_aws(e, msg="Couldn't get EFS file systems")

        results = list()
        for item in file_systems:
            item["CreationTime"] = str(item["CreationTime"])

            # In the time when MountPoint was introduced there was a need to add a suffix of network path before one could use it
            # AWS updated it and now there is no need to add a suffix. MountPoint is left for back-compatibility purpose
            # And new FilesystemAddress variable is introduced for direct use with other modules (e.g. mount)
            # AWS documentation is available here:
            # U(https://docs.aws.amazon.com/efs/latest/ug/gs-step-three-connect-to-ec2-instance.html)

            item["MountPoint"] = f".{item['FileSystemId']}.efs.{self.region}.amazonaws.com:/"
            item["FilesystemAddress"] = f"{item['FileSystemId']}.efs.{self.region}.amazonaws.com:/"

            if "Timestamp" in item["SizeInBytes"]:
                item["SizeInBytes"]["Timestamp"] = str(item["SizeInBytes"]["Timestamp"])
            result = camel_dict_to_snake_dict(item)
            result["tags"] = {}
            result["mount_targets"] = []
            # Set tags *after* doing camel to snake
            if result["life_cycle_state"] == self.STATE_AVAILABLE:
                try:
                    result["tags"] = self.get_tags(result["file_system_id"])
                except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
                    self.module.fail_json_aws(e, msg="Couldn't get EFS tags")
            results.append(result)
        return results


def prefix_to_attr(attr_id):
    """
    Helper method to convert ID prefix to mount target attribute
    """
    attr_by_prefix = {
        "fsmt-": "mount_target_id",
        "subnet-": "subnet_id",
        "eni-": "network_interface_id",
        "sg-": "security_groups",
    }
    return first_or_default(
        [attr_name for (prefix, attr_name) in attr_by_prefix.items() if str(attr_id).startswith(prefix)], "ip_address"
    )


def first_or_default(items, default=None):
    """
    Helper method to fetch first element of list (if exists)
    """
    for item in items:
        return item
    return default


def has_tags(available, required):
    """
    Helper method to determine if tag requested already exists
    """
    for key, value in required.items():
        if key not in available or value != available[key]:
            return False
    return True


def has_targets(available, required):
    """
    Helper method to determine if mount target requested already exists
    """
    grouped = group_list_of_dict(available)
    for value, field in required:
        if field not in grouped or value not in grouped[field]:
            return False
    return True


def group_list_of_dict(array):
    """
    Helper method to group list of dict to dict with all possible values
    """
    result = defaultdict(list)
    for item in array:
        for key, value in item.items():
            result[key] += value if isinstance(value, list) else [value]
    return result


def main():
    """
    Module action handler
    """
    argument_spec = dict(
        id=dict(),
        name=dict(aliases=["creation_token"]),
        tags=dict(type="dict", default={}),
        targets=dict(type="list", default=[], elements="str"),
    )

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

    connection = EFSConnection(module)

    name = module.params.get("name")
    fs_id = module.params.get("id")
    tags = module.params.get("tags")
    targets = module.params.get("targets")

    file_systems_info = connection.get_file_systems(fs_id, name)

    if tags:
        file_systems_info = [item for item in file_systems_info if has_tags(item["tags"], tags)]

    file_systems_info = connection.get_mount_targets_data(file_systems_info)
    file_systems_info = connection.get_security_groups_data(file_systems_info)

    if targets:
        targets = [(item, prefix_to_attr(item)) for item in targets]
        file_systems_info = [item for item in file_systems_info if has_targets(item["mount_targets"], targets)]

    module.exit_json(changed=False, efs=file_systems_info)


if __name__ == "__main__":
    main()
