#!/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: ec2_win_password
version_added: 1.0.0
short_description: Gets the default administrator password for EC2 Windows instances
description:
    - Gets the default administrator password from any EC2 Windows instance. The instance is referenced by its id (e.g. C(i-XXXXXXX)).
author: "Rick Mendes (@rickmendes)"
options:
  instance_id:
    description:
      - The instance id to get the password data from.
    required: true
    type: str
  key_file:
    description:
      - Path to the file containing the key pair used on the instance.
      - Conflicts with I(key_data).
    required: false
    type: path
  key_data:
    description:
      - The private key (usually stored in vault).
      - Conflicts with I(key_file),
    required: false
    type: str
  key_passphrase:
    description:
      - The passphrase for the instance key pair. The key must use DES or 3DES encryption for this module to decrypt it. You can use openssl to
        convert your password protected keys if they do not use DES or 3DES. ex) C(openssl rsa -in current_key -out new_key -des3).
    type: str
  wait:
    description:
      - Whether or not to wait for the password to be available before returning.
    type: bool
    default: false
  wait_timeout:
    description:
      - Number of seconds to wait before giving up.
    default: 120
    type: int

extends_documentation_fragment:
- amazon.aws.aws
- amazon.aws.ec2
- amazon.aws.boto3

requirements:
- cryptography
'''

EXAMPLES = '''
# Example of getting a password
- name: get the Administrator password
  community.aws.ec2_win_password:
    profile: my-boto-profile
    instance_id: i-XXXXXX
    region: us-east-1
    key_file: "~/aws-creds/my_test_key.pem"

# Example of getting a password using a variable
- name: get the Administrator password
  community.aws.ec2_win_password:
    profile: my-boto-profile
    instance_id: i-XXXXXX
    region: us-east-1
    key_data: "{{ ec2_private_key }}"

# Example of getting a password with a password protected key
- name: get the Administrator password
  community.aws.ec2_win_password:
    profile: my-boto-profile
    instance_id: i-XXXXXX
    region: us-east-1
    key_file: "~/aws-creds/my_protected_test_key.pem"
    key_passphrase: "secret"

# Example of waiting for a password
- name: get the Administrator password
  community.aws.ec2_win_password:
    profile: my-boto-profile
    instance_id: i-XXXXXX
    region: us-east-1
    key_file: "~/aws-creds/my_test_key.pem"
    wait: true
    wait_timeout: 45
'''

import datetime
import time
from base64 import b64decode

try:
    from cryptography.hazmat.backends import default_backend
    from cryptography.hazmat.primitives.asymmetric.padding import PKCS1v15
    from cryptography.hazmat.primitives.serialization import load_pem_private_key
    HAS_CRYPTOGRAPHY = True
except ImportError:
    HAS_CRYPTOGRAPHY = False

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

from ansible.module_utils._text import to_bytes

from ansible_collections.amazon.aws.plugins.module_utils.core import AnsibleAWSModule
from ansible_collections.amazon.aws.plugins.module_utils.ec2 import AWSRetry


def setup_module_object():
    argument_spec = dict(
        instance_id=dict(required=True),
        key_file=dict(required=False, default=None, type='path'),
        key_passphrase=dict(no_log=True, default=None, required=False),
        key_data=dict(no_log=True, default=None, required=False),
        wait=dict(type='bool', default=False, required=False),
        wait_timeout=dict(default=120, required=False, type='int'),
    )
    mutually_exclusive = [['key_file', 'key_data']]
    module = AnsibleAWSModule(argument_spec=argument_spec, mutually_exclusive=mutually_exclusive)
    return module


def _get_password(module, client, instance_id):
    try:
        data = client.get_password_data(aws_retry=True, InstanceId=instance_id)['PasswordData']
    except (botocore.exceptions.BotoCoreError, botocore.exceptions.ClientError) as e:
        module.fail_json_aws(e, msg='Failed to get password data')
    return data


def ec2_win_password(module):
    instance_id = module.params.get('instance_id')
    key_file = module.params.get('key_file')
    if module.params.get('key_passphrase') is None:
        b_key_passphrase = None
    else:
        b_key_passphrase = to_bytes(module.params.get('key_passphrase'), errors='surrogate_or_strict')
    if module.params.get('key_data') is None:
        b_key_data = None
    else:
        b_key_data = to_bytes(module.params.get('key_data'), errors='surrogate_or_strict')
    wait = module.params.get('wait')
    wait_timeout = module.params.get('wait_timeout')

    client = module.client('ec2', retry_decorator=AWSRetry.jittered_backoff())

    if wait:
        start = datetime.datetime.now()
        end = start + datetime.timedelta(seconds=wait_timeout)

        while datetime.datetime.now() < end:
            data = _get_password(module, client, instance_id)
            decoded = b64decode(data)
            if not decoded:
                time.sleep(5)
            else:
                break
    else:
        data = _get_password(module, client, instance_id)
        decoded = b64decode(data)

    if wait and datetime.datetime.now() >= end:
        module.fail_json(msg="wait for password timeout after %d seconds" % wait_timeout)

    if key_file is not None and b_key_data is None:
        try:
            with open(key_file, 'rb') as f:
                key = load_pem_private_key(f.read(), b_key_passphrase, default_backend())
        except IOError as e:
            # Handle bad files
            module.fail_json(msg="I/O error (%d) opening key file: %s" % (e.errno, e.strerror))
        except (ValueError, TypeError) as e:
            # Handle issues loading key
            module.fail_json(msg="unable to parse key file")
    elif b_key_data is not None and key_file is None:
        try:
            key = load_pem_private_key(b_key_data, b_key_passphrase, default_backend())
        except (ValueError, TypeError) as e:
            module.fail_json(msg="unable to parse key data")

    try:
        decrypted = key.decrypt(decoded, PKCS1v15())
    except ValueError as e:
        decrypted = None

    if decrypted is None:
        module.fail_json(msg="unable to decrypt password", win_password='', changed=False)
    else:
        if wait:
            elapsed = datetime.datetime.now() - start
            module.exit_json(win_password=decrypted, changed=False, elapsed=elapsed.seconds)
        else:
            module.exit_json(win_password=decrypted, changed=False)


def main():
    module = setup_module_object()

    if not HAS_CRYPTOGRAPHY:
        module.fail_json(msg='cryptography package required for this module.')

    ec2_win_password(module)


if __name__ == '__main__':
    main()