#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright: (c) 2020, 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

DOCUMENTATION = r'''
---
module: bigip_ssl_key_cert
short_description: Import/Delete SSL keys and certs from BIG-IP
description:
  - This module imports/deletes SSL keys and certificates on a BIG-IP.
    Keys can be imported from key files on the local disk, in PEM format.
    Certificates can be imported from certificate and key files on the local
    disk, in PEM format.
version_added: "1.6.0"
options:
  key_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).
    type: str
  state:
    description:
      - When C(present), ensures the key and/or cert is uploaded to the
        device. When C(absent), ensures the key and/or cert is removed
        from the device. If the key and/or cert is currently in use, the module
        will not be able to remove the key.
    type: str
    choices:
      - present
      - absent
    default: present
  key_name:
    description:
      - The name of the key.
    type: str
  passphrase:
    description:
      - Passphrase on key.
    type: str
  cert_content:
    description:
      - Sets the contents of a certificate directly to the specified value.
        This is used with lookup plugins or for anything with formatting or
      - C(content) must be provided when C(state) is C(present).
    type: str
  cert_name:
    description:
      - SSL Certificate Name. This is the cert name used when importing a certificate
        into the BIG-IP. It also determines the filenames of the objects on the LTM.
    type: str
  issuer_cert:
    description:
      - Issuer certificate used for OCSP monitoring.
      - This parameter is only valid on versions of BIG-IP 13.0.0 or above.
    type: str
  partition:
    description:
      - Device partition to manage resources on.
    type: str
    default: Common
extends_documentation_fragment: f5networks.f5_modules.f5
author:
  - Nitin Khanna (@nitinthewiz)
'''

EXAMPLES = r'''
- name: Import both key and cert
  bigip_ssl_key_cert:
    key_content: "{{ lookup('file', 'key.pem') }}"
    key_name: cert1
    cert_content: "{{ lookup('file', 'cert.pem') }}"
    cert_name: cert1
    state: present
    provider:
      password: secret
      server: lb.mydomain.com
      user: admin
  delegate_to: localhost
'''

RETURN = r'''
# only common fields returned
'''

import hashlib
import os
import re
from datetime import datetime

from ansible.module_utils.basic import (
    AnsibleModule, env_fallback
)

from ..module_utils.bigip import F5RestClient
from ..module_utils.common import (
    F5ModuleError, AnsibleF5Parameters, transform_name,
    f5_argument_spec, fq_name, merge_two_dicts
)
from ..module_utils.icontrol import (
    TransactionContextManager, upload_file, tmos_version
)
from ..module_utils.teem import send_teem

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


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

    api_map = {
        'sourcePath': 'source_path',
        'issuerCert': 'issuer_cert',
    }

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

    returnables = [
        'checksum',
        'source_path',
        'issuer_cert',
    ]

    updatables = [
        'key_checksum',
        'cert_checksum',
        'content',
        'issuer_cert',
        'source_path',
    ]


class ApiParameters(Parameters):
    @property
    def key_filename(self):
        if self._values['name'] is None:
            return None
        if not self._values['name'].endswith('.key'):
            return None
        return self._values['name']

    @property
    def key_source_path(self):
        if self.key_filename is None:
            return None
        if self._values['key_source_path'] is None:
            return None
        else:
            return self._values['key_source_path']

    @property
    def cert_filename(self):
        if self._values['name'] is None:
            return None
        if not self._values['name'].endswith('.crt'):
            return None
        return self._values['name']

    @property
    def cert_source_path(self):
        if self.cert_filename is None:
            return None
        if self._values['cert_source_path'] is None:
            return None
        else:
            return self._values['cert_source_path']

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

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


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 issuer_cert(self):
        if self._values['issuer_cert'] is None:
            return None
        name = fq_name(self.partition, self._values['issuer_cert'])
        if name.endswith('.crt'):
            return name
        else:
            return name + '.crt'

    @property
    def key_filename(self):
        if self.key_name is None:
            return None
        if self.key_name.endswith('.key'):
            return self.key_name
        else:
            return self.key_name + '.key'

    @property
    def cert_filename(self):
        if self.cert_name is None:
            return None
        if self.cert_name.endswith('.crt'):
            return self.cert_name
        else:
            return self.cert_name + '.crt'

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

    @property
    def cert_checksum(self):
        if self.cert_content is None:
            return None
        return self._get_hash(self.cert_content)

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

    @property
    def cert_source_path(self):
        result = 'file://' + os.path.join(
            self.download_path,
            self.cert_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:
            raise
        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.key_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

    @property
    def cert_source_path(self):
        if self.want.source_path is None:
            return None
        if self.want.source_path == self.have.source_path:
            if self.cert_content:
                return self.want.source_path
        if self.want.source_path != self.have.source_path:
            return self.want.source_path

    @property
    def cert_content(self):
        if self.want.cert_checksum != self.have.checksum:
            result = dict(
                checksum=self.want.cert_checksum,
                content=self.want.cert_content
            )
            return result


class ModuleManager(object):
    def __init__(self, *args, **kwargs):
        self.module = kwargs.get('module', None)
        self.client = F5RestClient(**self.module.params)
        self.want = ModuleParameters(params=self.module.params)
        self.have = ApiParameters()
        self.changes = UsableChanges()

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

    def exec_module(self):
        start = datetime.now().isoformat()
        version = tmos_version(self.client)
        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)
        send_teem(start, self.module, version)
        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 should_update(self):
        result = self._update_changed_options()
        if result:
            return True
        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 remove(self):
        if self.module.check_mode:
            return True
        self.remove_from_device()
        if self.exists():
            raise F5ModuleError("Failed to delete the resource.")
        return True

    def create(self):
        self._set_changed_options()
        if self.module.check_mode:
            return True
        self.create_on_device()
        if self.want.key_filename:
            self.remove_uploaded_file_from_device(self.want.key_filename)
        if self.want.cert_filename:
            self.remove_uploaded_file_from_device(self.want.cert_filename)
        return True

    def remove_uploaded_file_from_device(self, name):
        filepath = '/var/config/rest/downloads/{0}'.format(name)
        params = {
            "command": "run",
            "utilCmdArgs": filepath
        }
        uri = "https://{0}:{1}/mgmt/tm/util/unix-rm".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 resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return True
        raise F5ModuleError(resp.content)

    def exists(self):
        # Can't use TransactionContextManager here because
        # it expects end result code to be 200 or so. 404 causes
        # TransactionContextManager to fail.
        if self.want.key_name:
            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 resp.status == 404 or 'code' in response and response['code'] == 404:
                return False
            # if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            #     return True

            errors = [401, 403, 409, 500, 501, 502, 503, 504]

            if resp.status in errors or 'code' in response and response['code'] in errors:
                if 'message' in response:
                    raise F5ModuleError(response['message'])
                else:
                    raise F5ModuleError(resp.content)

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

            if resp.status == 404 or 'code' in response and response['code'] == 404:
                return False
            # if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            #     return True

            errors = [401, 403, 409, 500, 501, 502, 503, 504]

            if resp.status in errors or 'code' in response and response['code'] in errors:
                if 'message' in response:
                    raise F5ModuleError(response['message'])
                else:
                    raise F5ModuleError(resp.content)

        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 _prepare_links(self):
        # this is to ensure no duplicates are in the provided collection
        links = list()

        if self.want.key_name:
            key_link = "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)
            )
            links.append(key_link)

        if self.want.cert_name:
            cert_link = "https://{0}:{1}/mgmt/tm/sys/file/ssl-cert/{2}".format(
                self.client.provider['server'],
                self.client.provider['server_port'],
                transform_name(self.want.partition, self.want.cert_filename)
            )
            links.append(cert_link)

        return links

    def _prepare_links_for_update(self, params_dict):
        # this is to ensure no duplicates are in the provided collection
        links_and_params = list()

        if self.want.key_name:
            key_link = "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)
            )
            key_params_dict = params_dict.copy()
            key_params_dict['sourcePath'] = self.want.key_source_path
            links_and_params.append({'link': key_link, 'params': key_params_dict})

        if self.want.cert_name:
            cert_link = "https://{0}:{1}/mgmt/tm/sys/file/ssl-cert/{2}".format(
                self.client.provider['server'],
                self.client.provider['server_port'],
                transform_name(self.want.partition, self.want.cert_filename)
            )
            cert_params_dict = params_dict.copy()
            cert_params_dict['sourcePath'] = self.want.cert_source_path

            links_and_params.append({'link': cert_link, 'params': cert_params_dict})

        return links_and_params

    def _prepare_links_for_create(self, params_dict):
        # this is to ensure no duplicates are in the provided collection
        links_and_params = list()

        if self.want.key_name:
            key_link = "https://{0}:{1}/mgmt/tm/sys/file/ssl-key/".format(
                self.client.provider['server'],
                self.client.provider['server_port']
            )
            key_params_dict = params_dict.copy()
            key_params_dict['name'] = self.want.key_filename
            key_params_dict['sourcePath'] = self.want.key_source_path
            links_and_params.append({'link': key_link, 'params': key_params_dict})

        if self.want.cert_name:
            cert_link = "https://{0}:{1}/mgmt/tm/sys/file/ssl-cert/".format(
                self.client.provider['server'],
                self.client.provider['server_port']
            )
            cert_params_dict = params_dict.copy()
            cert_params_dict['name'] = self.want.cert_filename
            cert_params_dict['sourcePath'] = self.want.cert_source_path

            links_and_params.append({'link': cert_link, 'params': cert_params_dict})

        return links_and_params

    def create_on_device(self):
        params = self.changes.api_params()
        params['partition'] = self.want.partition

        # params['name'] = self.want.name

        links_and_params = self._prepare_links_for_create(params)

        if self.want.key_name:
            key_content = StringIO(self.want.key_content)
            self.upload_file_to_device(key_content, self.want.key_filename)

        if self.want.cert_name:
            cert_content = StringIO(self.want.cert_content)
            self.upload_file_to_device(cert_content, self.want.cert_filename)

        with TransactionContextManager(self.client) as transact:
            for link in links_and_params:
                resp = transact.api.post(link['link'], json=link['params'])
                try:
                    response = resp.json()
                except ValueError as ex:
                    raise F5ModuleError(str(ex))

                if not (resp.status in [200, 201] or 'code' in response and
                        response['code'] in [200, 201]):
                    raise F5ModuleError(resp.content)

        # This needs to be done because of the way that BIG-IP creates certificates.
        #
        # The extra params (such as OCSP and issuer stuff) are not available in the
        # payload. In a nutshell, the available resource attributes *change* after
        # a create so that *more* are available.
        if self.want.cert_name:
            params = self.want.api_params()
            if params:
                uri = "https://{0}:{1}/mgmt/tm/sys/file/ssl-cert/{2}".format(
                    self.client.provider['server'],
                    self.client.provider['server_port'],
                    transform_name(self.want.partition, self.want.cert_filename)
                )
                resp = self.client.api.put(uri, json=params)
                try:
                    response = resp.json()
                except ValueError as ex:
                    raise F5ModuleError(str(ex))

                if not (resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]):
                    raise F5ModuleError(resp.content)

        return True

    def update_on_device(self):
        params = self.changes.api_params()

        if self.want.key_name:
            key_content = StringIO(self.want.key_content)
            self.upload_file_to_device(key_content, self.want.key_filename)

        if self.want.cert_name:
            cert_content = StringIO(self.want.cert_content)
            self.upload_file_to_device(cert_content, self.want.cert_filename)

        links_and_params = self._prepare_links_for_update(params)
        with TransactionContextManager(self.client) as transact:
            for link in links_and_params:
                resp = transact.api.patch(link['link'], json=link['params'])
                try:
                    response = resp.json()
                except ValueError as ex:
                    raise F5ModuleError(str(ex))

                if not (resp.status in [200, 201] or 'code' in response and
                        response['code'] in [200, 201]):
                    raise F5ModuleError(resp.content)
        return True

    def remove_from_device(self):
        links = self._prepare_links()
        with TransactionContextManager(self.client) as transact:
            for link in links:
                resp = transact.api.delete(link)
                try:
                    response = resp.json()
                except ValueError as ex:
                    raise F5ModuleError(str(ex))

                if not (resp.status in [200, 201]):
                    raise F5ModuleError(resp.content)
        return True

    def read_current_from_device(self):
        final_response = {}
        # TransactionContextManager cannot be used for reading, for
        # whatever reason

        if self.want.key_name:
            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 resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
                response['key_checksum'] = response['checksum']
                response['key_source_path'] = response['sourcePath']
                final_response = merge_two_dicts(final_response, response)
            else:
                raise F5ModuleError(resp.content)

        if self.want.cert_name:
            uri = "https://{0}:{1}/mgmt/tm/sys/file/ssl-cert/{2}".format(
                self.client.provider['server'],
                self.client.provider['server_port'],
                transform_name(self.want.partition, self.want.cert_filename)
            )

            query = '?expandSubcollections=true'
            resp = self.client.api.get(uri + query)

            try:
                response = resp.json()
            except ValueError as ex:
                raise F5ModuleError(str(ex))

            if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
                response['cert_checksum'] = response['checksum']
                response['cert_source_path'] = response['sourcePath']
                final_response = merge_two_dicts(final_response, response)
            else:
                raise F5ModuleError(resp.content)

        return ApiParameters(params=final_response)


class ArgumentSpec(object):
    def __init__(self):
        self.supports_check_mode = True
        argument_spec = dict(
            key_name=dict(),
            key_content=dict(),
            passphrase=dict(
                no_log=True
            ),
            cert_name=dict(),
            cert_content=dict(),
            issuer_cert=dict(),
            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
    )

    try:
        mm = ModuleManager(module=module)
        results = mm.exec_module()
        module.exit_json(**results)
    except F5ModuleError as ex:
        module.fail_json(msg=str(ex))


if __name__ == '__main__':
    main()
