#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright: (c) 2017, F5 Networks Inc.
# 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': ['stableinterface'],
                    'supported_by': 'certified'}

DOCUMENTATION = r'''
---
module: bigip_ssl_key
short_description: Import/Delete SSL keys from BIG-IP
description:
  - This module will import/delete SSL keys on a BIG-IP. Keys can be imported
    from key files on the local disk, in PEM format.
version_added: 2.5
options:
  content:
    description:
      - Sets the contents of a key directly to the specified value. This is
        used with lookup plugins or for anything with formatting or templating.
        This must be provided when C(state) is C(present).
    aliases:
      - key_content
  state:
    description:
      - When C(present), ensures that the key is uploaded to the device. When
        C(absent), ensures that the key is removed from the device. If the key
        is currently in use, the module will not be able to remove the key.
    default: present
    choices:
      - present
      - absent
  name:
    description:
      - The name of the key.
    required: True
  passphrase:
    description:
      - Passphrase on key.
  partition:
    description:
      - Device partition to manage resources on.
    default: Common
    version_added: 2.5
notes:
  - This module does not behave like other modules that you might include in
    roles where referencing files or templates first looks in the role's
    files or templates directory. To have it behave that way, use the Ansible
    file or template lookup (see Examples). The lookups behave as expected in
    a role context.
extends_documentation_fragment: f5
requirements:
  - BIG-IP >= v12
author:
  - Tim Rupp (@caphrim007)
  - Wojciech Wypior (@wojtek0806)
'''

EXAMPLES = r'''
- name: Use a file lookup to import key
  bigip_ssl_key:
    name: key-name
    state: present
    content: "{{ lookup('file', '/path/to/key.key') }}"
    provider:
      server: lb.mydomain.com
      user: admin
      password: secret
  delegate_to: localhost

- name: Delete key
  bigip_ssl_key:
    name: key-name
    state: absent
    provider:
      server: lb.mydomain.com
      user: admin
      password: secret
  delegate_to: localhost
'''

RETURN = r'''
key_filename:
  description:
    - The name of the SSL certificate key. The C(key_filename) and
      C(cert_filename) will be similar to each other, however the
      C(key_filename) will have a C(.key) extension.
  returned: created
  type: string
  sample: cert1.key
key_checksum:
  description: SHA1 checksum of the key that was provided.
  returned: changed and created
  type: string
  sample: cf23df2207d99a74fbe169e3eba035e633b65d94
key_source_path:
  description: Path on BIG-IP where the source of the key is stored
  returned: created
  type: string
  sample: /var/config/rest/downloads/cert1.key
'''

import hashlib
import os
import re

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.basic import env_fallback

try:
    from library.module_utils.network.f5.bigip import F5RestClient
    from library.module_utils.network.f5.common import F5ModuleError
    from library.module_utils.network.f5.common import AnsibleF5Parameters
    from library.module_utils.network.f5.common import cleanup_tokens
    from library.module_utils.network.f5.common import f5_argument_spec
    from library.module_utils.network.f5.common import exit_json
    from library.module_utils.network.f5.common import fail_json
    from library.module_utils.network.f5.common import transform_name
    from library.module_utils.network.f5.icontrol import upload_file
except ImportError:
    from ansible.module_utils.network.f5.bigip import F5RestClient
    from ansible.module_utils.network.f5.common import F5ModuleError
    from ansible.module_utils.network.f5.common import AnsibleF5Parameters
    from ansible.module_utils.network.f5.common import cleanup_tokens
    from ansible.module_utils.network.f5.common import f5_argument_spec
    from ansible.module_utils.network.f5.common import exit_json
    from ansible.module_utils.network.f5.common import fail_json
    from ansible.module_utils.network.f5.common import transform_name
    from ansible.module_utils.network.f5.icontrol import upload_file

try:
    from StringIO import StringIO
except ImportError:
    from io import StringIO


class Parameters(AnsibleF5Parameters):
    download_path = '/var/config/rest/downloads'

    api_map = {
        'sourcePath': 'key_source_path'
    }

    updatables = [
        'key_checksum',
        'key_source_path',
    ]

    returnables = [
        'key_filename',
        'key_checksum',
        'key_source_path',
    ]

    api_attributes = [
        'passphrase',
        'sourcePath',
    ]


class ApiParameters(Parameters):
    @property
    def checksum(self):
        if self._values['checksum'] is None:
            return None
        pattern = r'SHA1:\d+:(?P<value>[\w+]{40})'
        matches = re.match(pattern, self._values['checksum'])
        if matches:
            return matches.group('value')
        else:
            return None


class ModuleParameters(Parameters):
    def _get_hash(self, content):
        k = hashlib.sha1()
        s = StringIO(content)
        while True:
            data = s.read(1024)
            if not data:
                break
            k.update(data.encode('utf-8'))
        return k.hexdigest()

    @property
    def key_filename(self):
        if self.name.endswith('.key'):
            return self.name
        else:
            return self.name + '.key'

    @property
    def key_checksum(self):
        if self.content is None:
            return None
        return self._get_hash(self.content)

    @property
    def key_source_path(self):
        result = 'file://' + os.path.join(
            self.download_path,
            self.key_filename
        )
        return result


class Changes(Parameters):
    def to_return(self):
        result = {}
        try:
            for returnable in self.returnables:
                result[returnable] = getattr(self, returnable)
            result = self._filter_params(result)
        except Exception:
            pass
        return result


class UsableChanges(Changes):
    pass


class ReportableChanges(Changes):
    pass


class Difference(object):
    def __init__(self, want, have=None):
        self.want = want
        self.have = have

    def compare(self, param):
        try:
            result = getattr(self, param)
            return result
        except AttributeError:
            return self.__default(param)

    def __default(self, param):
        attr1 = getattr(self.want, param)
        try:
            attr2 = getattr(self.have, param)
            if attr1 != attr2:
                return attr1
        except AttributeError:
            return attr1

    @property
    def key_checksum(self):
        if self.want.key_checksum is None:
            return None
        if self.want.key_checksum != self.have.checksum:
            return self.want.key_checksum

    @property
    def key_source_path(self):
        if self.want.key_source_path is None:
            return None
        if self.want.key_source_path == self.have.key_source_path:
            if self.key_checksum:
                return self.want.key_source_path
        if self.want.key_source_path != self.have.key_source_path:
                return self.want.key_source_path


class ModuleManager(object):
    def __init__(self, *args, **kwargs):
        self.module = kwargs.get('module', None)
        self.client = kwargs.get('client', None)
        self.want = ModuleParameters(params=self.module.params)
        self.have = ApiParameters()
        self.changes = UsableChanges()

    def _announce_deprecations(self, result):
        warnings = result.pop('__warnings', [])
        for warning in warnings:
            self.client.module.deprecate(
                msg=warning['msg'],
                version=warning['version']
            )

    def _set_changed_options(self):
        changed = {}
        for key in Parameters.returnables:
            if getattr(self.want, key) is not None:
                changed[key] = getattr(self.want, key)
        if changed:
            self.changes = UsableChanges(params=changed)

    def _update_changed_options(self):
        diff = Difference(self.want, self.have)
        updatables = Parameters.updatables
        changed = dict()
        for k in updatables:
            change = diff.compare(k)
            if change is None:
                continue
            else:
                if isinstance(change, dict):
                    changed.update(change)
                else:
                    changed[k] = change
        if changed:
            self.changes = UsableChanges(params=changed)
            return True
        return False

    def exec_module(self):
        changed = False
        result = dict()
        state = self.want.state

        if state == "present":
            changed = self.present()
        elif state == "absent":
            changed = self.absent()

        reportable = ReportableChanges(params=self.changes.to_return())
        changes = reportable.to_return()
        result.update(**changes)
        result.update(dict(changed=changed))
        self._announce_deprecations(result)
        return result

    def present(self):
        if self.exists():
            return self.update()
        else:
            return self.create()

    def absent(self):
        if self.exists():
            return self.remove()
        return False

    def update(self):
        self.have = self.read_current_from_device()
        if not self.should_update():
            return False
        if self.module.check_mode:
            return True
        self.update_on_device()
        return True

    def should_update(self):
        result = self._update_changed_options()
        if result:
            return True
        return False

    def create(self):
        if self.want.content is None:
            return False
        self._set_changed_options()
        if self.module.check_mode:
            return True
        self.create_on_device()
        return True

    def remove(self):
        if self.module.check_mode:
            return True
        self.remove_from_device()
        if self.exists():
            raise F5ModuleError("Failed to delete the key")
        return True

    def exists(self):
        uri = "https://{0}:{1}/mgmt/tm/sys/file/ssl-key/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.key_filename)
        )
        resp = self.client.api.get(uri)
        try:
            response = resp.json()
        except ValueError:
            return False
        if resp.status == 404 or 'code' in response and response['code'] == 404:
            return False
        return True

    def upload_file_to_device(self, content, name):
        url = 'https://{0}:{1}/mgmt/shared/file-transfer/uploads'.format(
            self.client.provider['server'],
            self.client.provider['server_port']
        )
        try:
            upload_file(self.client, url, content, name)
        except F5ModuleError:
            raise F5ModuleError(
                "Failed to upload the file."
            )

    def update_on_device(self):
        content = StringIO(self.want.content)
        self.upload_file_to_device(content, self.want.key_filename)
        params = self.changes.api_params()
        uri = "https://{0}:{1}/mgmt/tm/sys/file/ssl-key/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.key_filename)
        )
        resp = self.client.api.put(uri, json=params)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if 'code' in response and response['code'] == 400:
            if 'message' in response:
                raise F5ModuleError(response['message'])
            else:
                raise F5ModuleError(resp.content)

    def create_on_device(self):
        params = self.changes.api_params()
        content = StringIO(self.want.content)
        self.upload_file_to_device(content, self.want.key_filename)
        params['name'] = self.want.key_filename
        params['partition'] = self.want.partition
        uri = "https://{0}:{1}/mgmt/tm/sys/file/ssl-key/".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
        )
        resp = self.client.api.post(uri, json=params)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if 'code' in response and response['code'] in [400, 403]:
            if 'message' in response:
                raise F5ModuleError(response['message'])
            else:
                raise F5ModuleError(resp.content)

    def read_current_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/sys/file/ssl-key/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.key_filename)
        )
        resp = self.client.api.get(uri)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if 'code' in response and response['code'] == 400:
            if 'message' in response:
                raise F5ModuleError(response['message'])
            else:
                raise F5ModuleError(resp.content)
        return ApiParameters(params=response)

    def remove_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/sys/file/ssl-key/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.key_filename)
        )
        response = self.client.api.delete(uri)
        if response.status == 200:
            return True
        raise F5ModuleError(response.content)


class ArgumentSpec(object):
    def __init__(self):
        self.supports_check_mode = True
        argument_spec = dict(
            name=dict(
                required=True
            ),
            content=dict(
                aliases=['key_content']
            ),
            passphrase=dict(
                no_log=True
            ),
            state=dict(
                required=False,
                default='present',
                choices=['absent', 'present']
            ),
            partition=dict(
                default='Common',
                fallback=(env_fallback, ['F5_PARTITION'])
            )
        )
        self.argument_spec = {}
        self.argument_spec.update(f5_argument_spec)
        self.argument_spec.update(argument_spec)


def main():
    spec = ArgumentSpec()

    module = AnsibleModule(
        argument_spec=spec.argument_spec,
        supports_check_mode=spec.supports_check_mode
    )

    client = F5RestClient(**module.params)

    try:
        mm = ModuleManager(module=module, client=client)
        results = mm.exec_module()
        cleanup_tokens(client)
        exit_json(module, results, client)
    except F5ModuleError as ex:
        cleanup_tokens(client)
        fail_json(module, ex, client)


if __name__ == '__main__':
    main()