#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright 2017 F5 Networks Inc.
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.

ANSIBLE_METADATA = {
    'status': ['preview'],
    'supported_by': 'community',
    'metadata_version': '1.0'
}

DOCUMENTATION = '''
---
module: bigip_virtual_address
short_description: Manage LTM virtual addresses on a BIG-IP.
description:
  - Manage LTM virtual addresses on a BIG-IP.
version_added: "2.4"
options:
  address:
    description:
      - Virtual address. This value cannot be modified after it is set.
    required: True
    aliases:
      - name
  netmask:
    description:
      - Netmask of the provided virtual address. This value cannot be
        modified after it is set.
    default: 255.255.255.255
  connection_limit:
    description:
      - Specifies the number of concurrent connections that the system
        allows on this virtual address.
  arp_state:
    description:
      - Specifies whether the system accepts ARP requests. When (disabled),
        specifies that the system does not accept ARP requests. Note that
        both ARP and ICMP Echo must be disabled in order for forwarding
        virtual servers using that virtual address to forward ICMP packets.
        If (enabled), then the packets are dropped.
    choices:
      - enabled
      - disabled
  auto_delete:
    description:
      - Specifies whether the system automatically deletes the virtual
        address with the deletion of the last associated virtual server.
        When C(disabled), specifies that the system leaves the virtual
        address even when all associated virtual servers have been deleted.
        When creating the virtual address, the default value is C(enabled).
    choices:
      - enabled
      - disabled
  icmp_echo:
    description:
      - Specifies how the systems sends responses to (ICMP) echo requests
        on a per-virtual address basis for enabling route advertisement.
        When C(enabled), the BIG-IP system intercepts ICMP echo request
        packets and responds to them directly. When C(disabled), the BIG-IP
        system passes ICMP echo requests through to the backend servers.
        When (selective), causes the BIG-IP system to internally enable or
        disable responses based on virtual server state; C(when_any_available),
        C(when_all_available, or C(always), regardless of the state of any
        virtual servers.
    choices:
      - enabled
      - disabled
      - selective
  state:
    description:
      - The virtual address state. If C(absent), an attempt to delete the
        virtual address will be made. This will only succeed if this
        virtual address is not in use by a virtual server. C(present) creates
        the virtual address and enables it. If C(enabled), enable the virtual
        address if it exists. If C(disabled), create the virtual address if
        needed, and set state to C(disabled).
    default: present
    choices:
      - present
      - absent
      - enabled
      - disabled
  advertise_route:
    description:
      - Specifies what routes of the virtual address the system advertises.
        When C(when_any_available), advertises the route when any virtual
        server is available. When C(when_all_available), advertises the
        route when all virtual servers are available. When (always), always
        advertises the route regardless of the virtual servers available.
    choices:
      - always
      - when_all_available
      - when_any_available
  use_route_advertisement:
    description:
      - Specifies whether the system uses route advertisement for this
        virtual address. When disabled, the system does not advertise
        routes for this virtual address.
    choices:
      - yes
      - no
notes:
  - Requires the f5-sdk Python package on the host. This is as easy as pip
    install f5-sdk.
  - Requires the netaddr Python package on the host. This is as easy as pip
    install netaddr.
extends_documentation_fragment: f5
author:
  - Tim Rupp (@caphrim007)
'''

EXAMPLES = '''
- name: Add virtual address
  bigip_virtual_address:
      server: "lb.mydomain.net"
      user: "admin"
      password: "secret"
      state: "present"
      partition: "Common"
      address: "10.10.10.10"
  delegate_to: localhost

- name: Enable route advertisement on the virtual address
  bigip_virtual_address:
      server: "lb.mydomain.net"
      user: "admin"
      password: "secret"
      state: "present"
      address: "10.10.10.10"
      use_route_advertisement: yes
  delegate_to: localhost
'''

RETURN = '''
use_route_advertisement:
    description: The new setting for whether to use route advertising or not.
    returned: changed
    type: bool
    sample: true
auto_delete:
    description: New setting for auto deleting virtual address.
    returned: changed
    type: string
    sample: enabled
icmp_echo:
    description: New ICMP echo setting applied to virtual address.
    returned: changed
    type: string
    sample: disabled
connection_limit:
    description: The new connection limit of the virtual address.
    returned: changed
    type: int
    sample: 1000
netmask:
    description: The netmask of the virtual address.
    returned: created
    type: int
    sample: 2345
arp_state:
    description: The new way the virtual address handles ARP requests.
    returned: changed
    type: string
    sample: disabled
address:
    description: The address of the virtual address.
    returned: created
    type: int
    sample: 2345
state:
    description: The new state of the virtual address.
    returned: changed
    type: string
    sample: disabled
'''

try:
    import netaddr
    HAS_NETADDR = True
except ImportError:
    HAS_NETADDR = False

from ansible.module_utils.basic import BOOLEANS_TRUE
from ansible.module_utils.basic import BOOLEANS_FALSE
from ansible.module_utils.f5_utils import (
    AnsibleF5Client,
    AnsibleF5Parameters,
    HAS_F5SDK,
    F5ModuleError,
    iControlUnexpectedHTTPError
)


class Parameters(AnsibleF5Parameters):
    api_map = {
        'routeAdvertisement': 'use_route_advertisement',
        'autoDelete': 'auto_delete',
        'icmpEcho': 'icmp_echo',
        'connectionLimit': 'connection_limit',
        'serverScope': 'advertise_route',
        'mask': 'netmask',
        'arp': 'arp_state'
    }

    updatables = [
        'use_route_advertisement', 'auto_delete', 'icmp_echo', 'connection_limit',
        'arp_state', 'enabled', 'advertise_route'
    ]

    returnables = [
        'use_route_advertisement', 'auto_delete', 'icmp_echo', 'connection_limit',
        'netmask', 'arp_state', 'address', 'state'
    ]

    api_attributes = [
        'routeAdvertisement', 'autoDelete', 'icmpEcho', 'connectionLimit',
        'advertiseRoute', 'arp', 'mask', 'enabled', 'serverScope'
    ]

    @property
    def advertise_route(self):
        if self._values['advertise_route'] is None:
            return None
        elif self._values['advertise_route'] in ['any', 'when_any_available']:
            return 'any'
        elif self._values['advertise_route'] in ['all', 'when_all_available']:
            return 'all'
        elif self._values['advertise_route'] in ['none', 'always']:
            return 'none'

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

    @property
    def use_route_advertisement(self):
        if self._values['use_route_advertisement'] is None:
            return None
        elif self._values['use_route_advertisement'] in BOOLEANS_TRUE:
            return 'enabled'
        elif self._values['use_route_advertisement'] == 'enabled':
            return 'enabled'
        else:
            return 'disabled'

    @property
    def enabled(self):
        if self._values['state'] in ['enabled', 'present']:
            return 'yes'
        elif self._values['enabled'] in BOOLEANS_TRUE:
            return 'yes'
        elif self._values['state'] == 'disabled':
            return 'no'
        elif self._values['enabled'] in BOOLEANS_FALSE:
            return 'no'
        else:
            return None

    @property
    def address(self):
        if self._values['address'] is None:
            return None
        try:
            ip = netaddr.IPAddress(self._values['address'])
            return str(ip)
        except netaddr.core.AddrFormatError:
            raise F5ModuleError(
                "The provided 'address' is not a valid IP address"
            )

    @property
    def netmask(self):
        if self._values['netmask'] is None:
            return None
        try:
            ip = netaddr.IPAddress(self._values['netmask'])
            return str(ip)
        except netaddr.core.AddrFormatError:
            raise F5ModuleError(
                "The provided 'netmask' is not a valid IP address"
            )

    @property
    def auto_delete(self):
        if self._values['auto_delete'] is None:
            return None
        elif self._values['auto_delete'] in BOOLEANS_TRUE:
            return True
        elif self._values['auto_delete'] == 'enabled':
            return True
        else:
            return False

    @property
    def state(self):
        if self.enabled == 'yes' and self._values['state'] != 'present':
            return 'enabled'
        elif self.enabled == 'no':
            return 'disabled'
        else:
            return self._values['state']

    def to_return(self):
        result = {}
        for returnable in self.returnables:
            result[returnable] = getattr(self, returnable)
        result = self._filter_params(result)
        return result

    def api_params(self):
        result = {}
        for api_attribute in self.api_attributes:
            if api_attribute in self.api_map:
                result[api_attribute] = getattr(
                    self, self.api_map[api_attribute])
            else:
                result[api_attribute] = getattr(self, api_attribute)
        result = self._filter_params(result)
        return result


class ModuleManager(object):
    def __init__(self, client):
        self.client = client
        self.have = None
        self.want = Parameters(self.client.module.params)
        self.changes = Parameters()

    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 = Parameters(changed)

    def _update_changed_options(self):
        changed = {}
        for key in Parameters.updatables:
            if getattr(self.want, key) is not None:
                attr1 = getattr(self.want, key)
                attr2 = getattr(self.have, key)
                if attr1 != attr2:
                    changed[key] = attr1
        if changed:
            self.changes = Parameters(changed)
            return True
        return False

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

        try:
            if state in ['present', 'enabled', 'disabled']:
                changed = self.present()
            elif state == "absent":
                changed = self.absent()
        except iControlUnexpectedHTTPError as e:
            raise F5ModuleError(str(e))

        changes = self.changes.to_return()
        result.update(**changes)
        result.update(dict(changed=changed))
        return result

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

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

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

    def read_current_from_device(self):
        resource = self.client.api.tm.ltm.virtual_address_s.virtual_address.load(
            name=self.want.address,
            partition=self.want.partition
        )
        result = resource.attrs
        return Parameters(result)

    def exists(self):
        result = self.client.api.tm.ltm.virtual_address_s.virtual_address.exists(
            name=self.want.address,
            partition=self.want.partition
        )
        return result

    def update(self):
        self.have = self.read_current_from_device()
        if self.want.netmask is not None:
            if self.have.netmask != self.want.netmask:
                raise F5ModuleError(
                    "The netmask cannot be changed. Delete and recreate"
                    "the virtual address if you need to do this."
                )
        if self.want.address is not None:
            if self.have.address != self.want.address:
                raise F5ModuleError(
                    "The address cannot be changed. Delete and recreate"
                    "the virtual address if you need to do this."
                )
        if not self.should_update():
            return False
        if self.client.check_mode:
            return True
        self.update_on_device()
        return True

    def update_on_device(self):
        params = self.want.api_params()
        resource = self.client.api.tm.ltm.virtual_address_s.virtual_address.load(
            name=self.want.address,
            partition=self.want.partition
        )
        resource.modify(**params)

    def create(self):
        self._set_changed_options()
        if self.client.check_mode:
            return True
        self.create_on_device()
        if self.exists():
            return True
        else:
            raise F5ModuleError("Failed to create the virtual address")

    def create_on_device(self):
        params = self.want.api_params()
        self.client.api.tm.ltm.virtual_address_s.virtual_address.create(
            name=self.want.address,
            partition=self.want.partition,
            address=self.want.address,
            **params
        )

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

    def remove_from_device(self):
        resource = self.client.api.tm.ltm.virtual_address_s.virtual_address.load(
            name=self.want.address,
            partition=self.want.partition
        )
        resource.delete()


class ArgumentSpec(object):
    def __init__(self):
        self.supports_check_mode = True
        self.argument_spec = dict(
            state=dict(
                default='present',
                choices=['present', 'absent', 'disabled', 'enabled']
            ),
            address=dict(
                type='str',
                required=True,
                aliases=['name']
            ),
            netmask=dict(
                type='str',
                default='255.255.255.255',
            ),
            connection_limit=dict(
                type='int'
            ),
            arp_state=dict(
                choices=['enabled', 'disabled'],
            ),
            auto_delete=dict(
                choices=['enabled', 'disabled'],
            ),
            icmp_echo=dict(
                choices=['enabled', 'disabled', 'selective'],
            ),
            advertise_route=dict(
                choices=['always', 'when_all_available', 'when_any_available'],
            ),
            use_route_advertisement=dict(
                type='bool'
            )
        )
        self.f5_product_name = 'bigip'


def main():
    if not HAS_F5SDK:
        raise F5ModuleError("The python f5-sdk module is required")

    spec = ArgumentSpec()

    client = AnsibleF5Client(
        argument_spec=spec.argument_spec,
        supports_check_mode=spec.supports_check_mode,
        f5_product_name=spec.f5_product_name
    )

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


if __name__ == '__main__':
    main()
