#!/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': ['preview'],
                    'supported_by': 'certified'}

DOCUMENTATION = r'''
---
module: bigip_monitor_tcp_half_open
short_description: Manages F5 BIG-IP LTM tcp half-open monitors
description: Manages F5 BIG-IP LTM tcp half-open monitors.
version_added: 2.4
options:
  name:
    description:
      - Monitor name.
    type: str
    required: True
  parent:
    description:
      - The parent template of this monitor template. Once this value has
        been set, it cannot be changed. By default, this value is the C(tcp_half_open)
        parent on the C(Common) partition.
    type: str
    default: /Common/tcp_half_open
  description:
    description:
      - The description of the monitor.
    type: str
    version_added: 2.7
  ip:
    description:
      - IP address part of the IP/port definition. If this parameter is not
        provided when creating a new monitor, then the default value will be
        '*'.
      - If this value is an IP address, and the C(type) is C(tcp) (the default),
        then a C(port) number must be specified.
    type: str
  port:
    description:
      - Port address part of the IP/port definition. If this parameter is not
        provided when creating a new monitor, then the default value will be
        '*'. Note that if specifying an IP address, a value between 1 and 65535
        must be specified
    type: str
    version_added: 2.5
  interval:
    description:
      - The interval specifying how frequently the monitor instance of this
        template will run. If this parameter is not provided when creating
        a new monitor, then the default value will be 5. This value B(must)
        be less than the C(timeout) value.
    type: int
  timeout:
    description:
      - The number of seconds in which the node or service must respond to
        the monitor request. If the target responds within the set time
        period, it is considered up. If the target does not respond within
        the set time period, it is considered down. You can change this
        number to any number you want, however, it should be 3 times the
        interval number of seconds plus 1 second. If this parameter is not
        provided when creating a new monitor, then the default value will be 16.
    type: int
  time_until_up:
    description:
      - Specifies the amount of time in seconds after the first successful
        response before a node will be marked up. A value of 0 will cause a
        node to be marked up immediately after a valid response is received
        from the node. If this parameter is not provided when creating
        a new monitor, then the default value will be 0.
    type: int
  partition:
    description:
      - Device partition to manage resources on.
    type: str
    default: Common
    version_added: 2.5
  state:
    description:
      - When C(present), ensures that the monitor exists.
      - When C(absent), ensures the monitor is removed.
    type: str
    choices:
      - present
      - absent
    default: present
    version_added: 2.5
notes:
  - Requires BIG-IP software version >= 12
extends_documentation_fragment: f5
author:
  - Tim Rupp (@caphrim007)
  - Wojciech Wypior (@wojtek0806)
'''

EXAMPLES = r'''
- name: Create TCP half-open Monitor
  bigip_monitor_tcp_half_open:
    state: present
    ip: 10.10.10.10
    name: my_tcp_monitor
    provider:
      server: lb.mydomain.com
      user: admin
      password: secret
  delegate_to: localhost

- name: Remove TCP half-open Monitor
  bigip_monitor_tcp_half_open:
    state: absent
    name: my_tcp_monitor
    provider:
      server: lb.mydomain.com
      user: admin
      password: secret
  delegate_to: localhost

- name: Add half-open monitor for all addresses, port 514
  bigip_monitor_tcp_half_open:
    port: 514
    name: my_tcp_monitor
    provider:
      password: secret
      server: lb.mydomain.com
      user: admin
  delegate_to: localhost
'''

RETURN = r'''
parent:
  description: New parent template of the monitor.
  returned: changed
  type: str
  sample: tcp
description:
  description: The description of the monitor.
  returned: changed
  type: str
  sample: Important Monitor
ip:
  description: The new IP of IP/port definition.
  returned: changed
  type: str
  sample: 10.12.13.14
interval:
  description: The new interval in which to run the monitor check.
  returned: changed
  type: int
  sample: 2
timeout:
  description: The new timeout in which the remote system must respond to the monitor.
  returned: changed
  type: int
  sample: 10
time_until_up:
  description: The new time in which to mark a system as up after first successful response.
  returned: changed
  type: int
  sample: 2
'''

import os

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 f5_argument_spec
    from library.module_utils.network.f5.common import transform_name
    from library.module_utils.network.f5.ipaddress import is_valid_ip
    from library.module_utils.network.f5.compare import cmp_str_with_none
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 f5_argument_spec
    from ansible.module_utils.network.f5.common import transform_name
    from ansible.module_utils.network.f5.ipaddress import is_valid_ip
    from ansible.module_utils.network.f5.compare import cmp_str_with_none


class Parameters(AnsibleF5Parameters):
    api_map = {
        'timeUntilUp': 'time_until_up',
        'defaultsFrom': 'parent',
        'recv': 'receive',
    }

    api_attributes = [
        'timeUntilUp',
        'defaultsFrom',
        'interval',
        'timeout',
        'destination',
        'description',
    ]

    returnables = [
        'parent',
        'ip',
        'port',
        'interval',
        'timeout',
        'time_until_up',
        'description',
    ]

    updatables = [
        'destination',
        'interval',
        'timeout',
        'time_until_up',
        'description',
    ]

    @property
    def destination(self):
        if self.ip is None and self.port is None:
            return None
        destination = '{0}:{1}'.format(self.ip, self.port)
        return destination

    @destination.setter
    def destination(self, value):
        ip, port = value.split(':')
        self._values['ip'] = ip
        self._values['port'] = port

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

        # Per BZ617284, the BIG-IP UI does not raise a warning about this.
        # So I raise the error instead.
        if 1 > int(self._values['interval']) > 86400:
            raise F5ModuleError(
                "Interval value must be between 1 and 86400"
            )
        return int(self._values['interval'])

    @property
    def timeout(self):
        if self._values['timeout'] is None:
            return None
        return int(self._values['timeout'])

    @property
    def ip(self):
        if self._values['ip'] is None:
            return None
        elif self._values['ip'] in ['*', '0.0.0.0']:
            return '*'
        elif is_valid_ip(self._values['ip']):
            return self._values['ip']
        raise F5ModuleError(
            "The provided 'ip' parameter is not an IP address."
        )

    @property
    def port(self):
        if self._values['port'] is None:
            return None
        elif self._values['port'] == '*':
            return '*'
        return int(self._values['port'])

    @property
    def time_until_up(self):
        if self._values['time_until_up'] is None:
            return None
        return int(self._values['time_until_up'])

    @property
    def parent(self):
        if self._values['parent'] is None:
            return None
        if self._values['parent'].startswith('/'):
            parent = os.path.basename(self._values['parent'])
            result = '/{0}/{1}'.format(self.partition, parent)
        else:
            result = '/{0}/{1}'.format(self.partition, self._values['parent'])
        return result

    @property
    def type(self):
        return 'tcp_half_open'


class ApiParameters(Parameters):
    @property
    def description(self):
        if self._values['description'] in [None, 'none']:
            return None
        return self._values['description']


class ModuleParameters(Parameters):
    @property
    def description(self):
        if self._values['description'] is None:
            return None
        elif self._values['description'] in ['none', '']:
            return ''
        return self._values['description']


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:
            result = self.__default(param)
            return result

    @property
    def parent(self):
        if self.want.parent != self.have.parent:
            raise F5ModuleError(
                "The parent monitor cannot be changed"
            )

    @property
    def destination(self):
        if self.want.ip is None and self.want.port is None:
            return None
        if self.want.port is None:
            self.want.update({'port': self.have.port})
        if self.want.ip is None:
            self.want.update({'ip': self.have.ip})

        if self.want.port in [None, '*'] and self.want.ip != '*':
            raise F5ModuleError(
                "Specifying an IP address requires that a port number be specified"
            )

        if self.want.destination != self.have.destination:
            return self.want.destination

    @property
    def interval(self):
        if self.want.timeout is not None and self.want.interval is not None:
            if self.want.interval >= self.want.timeout:
                raise F5ModuleError(
                    "Parameter 'interval' must be less than 'timeout'."
                )
        elif self.want.timeout is not None:
            if self.have.interval >= self.want.timeout:
                raise F5ModuleError(
                    "Parameter 'interval' must be less than 'timeout'."
                )
        elif self.want.interval is not None:
            if self.want.interval >= self.have.timeout:
                raise F5ModuleError(
                    "Parameter 'interval' must be less than 'timeout'."
                )
        if self.want.interval != self.have.interval:
            return self.want.interval

    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 description(self):
        return cmp_str_with_none(self.want.description, self.have.description)


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

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

    def exists(self):
        uri = "https://{0}:{1}/mgmt/tm/ltm/monitor/tcp-half-open/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        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 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()
        self._set_default_creation_values()
        if self.module.check_mode:
            return True
        self.create_on_device()
        return True

    def _set_default_creation_values(self):
        if self.want.timeout is None:
            self.want.update({'timeout': 16})
        if self.want.interval is None:
            self.want.update({'interval': 5})
        if self.want.time_until_up is None:
            self.want.update({'time_until_up': 0})
        if self.want.ip is None:
            self.want.update({'ip': '*'})
        if self.want.port is None:
            self.want.update({'port': '*'})

    def create_on_device(self):
        params = self.changes.api_params()
        params['name'] = self.want.name
        params['partition'] = self.want.partition
        uri = "https://{0}:{1}/mgmt/tm/ltm/monitor/tcp-half-open/".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 update_on_device(self):
        params = self.changes.api_params()
        uri = "https://{0}:{1}/mgmt/tm/ltm/monitor/tcp-half-open/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        resp = self.client.api.patch(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 absent(self):
        if self.exists():
            return self.remove()
        return False

    def remove_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/ltm/monitor/tcp-half-open/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        resp = self.client.api.delete(uri)
        if resp.status == 200:
            return True

    def read_current_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/ltm/monitor/tcp-half-open/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        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)


class ArgumentSpec(object):
    def __init__(self):
        self.supports_check_mode = True
        argument_spec = dict(
            name=dict(required=True),
            parent=dict(default='/Common/tcp_half_open'),
            description=dict(),
            ip=dict(),
            port=dict(),
            interval=dict(type='int'),
            timeout=dict(type='int'),
            time_until_up=dict(type='int'),
            state=dict(
                default='present',
                choices=['present', 'absent']
            ),
            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()
