#!/usr/bin/python
#
# 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 = {'metadata_version': '1.1',
                    'status': ['preview'],
                    'supported_by': 'community'}

DOCUMENTATION = '''
---
module: ce_netstream_export
version_added: "2.4"
short_description: Manages netstream export on HUAWEI CloudEngine switches.
description:
    - Configure NetStream flow statistics exporting and versions for exported packets on HUAWEI CloudEngine switches.
author: Zhijin Zhou (@CloudEngine-Ansible)
notes:
options:
    type:
        description:
            - Specifies NetStream feature.
        required: true
        choices: ['ip', 'vxlan']
        default: null
    source_ip:
        description:
            - Specifies source address which can be IPv6 or IPv4 of the exported NetStream packet.
        required: false
        default: null
    host_ip:
        description:
            - Specifies destination address which can be IPv6 or IPv4 of the exported NetStream packet.
        required: false
        default: null
    host_port:
        description:
            - Specifies the destination UDP port number of the exported packets.
              The value is an integer that ranges from 1 to 65535.
        required: false
        default: null
    host_vpn:
        description:
            - Specifies the VPN instance of the exported packets carrying flow statistics.
              Ensure the VPN instance has been created on the device.
        required: false
        default: null
    version:
        description:
            - Sets the version of exported packets.
        required: false
        choices: ['5', '9']
        default: null
    as_option:
        description:
            - Specifies the AS number recorded in the statistics as the original or the peer AS number.
        required: false
        choices: ['origin', 'peer']
        default: null
    bgp_nexthop:
        description:
            - Configures the statistics to carry BGP next hop information. Currently, only V9 supports the exported
              packets carrying BGP next hop information.
        required: false
        choices: ['enable','disable']
        default: 'disable'
    state:
        description:
            - Manage the state of the resource.
        required: false
        choices: ['present','absent']
        default: present
'''

EXAMPLES = '''
- name: netstream export module test
  hosts: cloudengine
  connection: local
  gather_facts: no
  vars:
    cli:
      host: "{{ inventory_hostname }}"
      port: "{{ ansible_ssh_port }}"
      username: "{{ username }}"
      password: "{{ password }}"
      transport: cli

  tasks:

  - name: Configures the source address for the exported packets carrying IPv4 flow statistics.
    ce_netstream_export:
      type: ip
      source_ip: 192.8.2.2
      provider: "{{ cli }}"

  - name: Configures the source IP address for the exported packets carrying VXLAN flexible flow statistics.
    ce_netstream_export:
      type: vxlan
      source_ip: 192.8.2.3
      provider: "{{ cli }}"

  - name: Configures the destination IP address and destination UDP port number for the exported packets carrying IPv4 flow statistics.
    ce_netstream_export:
      type: ip
      host_ip: 192.8.2.4
      host_port: 25
      host_vpn: test
      provider: "{{ cli }}"

  - name: Configures the destination IP address and destination UDP port number for the exported packets carrying VXLAN flexible flow statistics.
    ce_netstream_export:
      type: vxlan
      host_ip: 192.8.2.5
      host_port: 26
      host_vpn: test
      provider: "{{ cli }}"

  - name: Configures the version number of the exported packets carrying IPv4 flow statistics.
    ce_netstream_export:
      type: ip
      version: 9
      as_option: origin
      bgp_nexthop: enable
      provider: "{{ cli }}"

  - name: Configures the version for the exported packets carrying VXLAN flexible flow statistics.
    ce_netstream_export:
      type: vxlan
      version: 9
      provider: "{{ cli }}"
'''

RETURN = '''
proposed:
    description: k/v pairs of parameters passed into module
    returned: always
    type: dict
    sample: {
                "as_option": "origin",
                "bgp_nexthop": "enable",
                "host_ip": "192.8.5.6",
                "host_port": "26",
                "host_vpn": "test",
                "source_ip": "192.8.2.5",
                "state": "present",
                "type": "ip",
                "version": "9"
            }
existing:
    description: k/v pairs of existing attributes on the device
    returned: always
    type: dict
    sample: {
                "as_option": null,
                "bgp_nexthop": "disable",
                "host_ip": null,
                "host_port": null,
                "host_vpn": null,
                "source_ip": null,
                "type": "ip",
                "version": null
            }
end_state:
    description: k/v pairs of end attributes on the device
    returned: always
    type: dict
    sample: {
                "as_option": "origin",
                "bgp_nexthop": "enable",
                "host_ip": "192.8.5.6",
                "host_port": "26",
                "host_vpn": "test",
                "source_ip": "192.8.2.5",
                "type": "ip",
                "version": "9"
            }
updates:
    description: command list sent to the device
    returned: always
    type: list
    sample: [
                "netstream export ip source 192.8.2.5",
                "netstream export ip host 192.8.5.6 26 vpn-instance test",
                "netstream export ip version 9 origin-as bgp-nexthop"
            ]
changed:
    description: check to see if a change was made on the device
    returned: always
    type: boolean
    sample: true
'''

import re
from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.network.cloudengine.ce import get_config, load_config
from ansible.module_utils.network.cloudengine.ce import ce_argument_spec


def is_ipv4_addr(ip_addr):
    """check ipaddress validate"""

    rule1 = r'(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])\.'
    rule2 = r'(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])'
    ipv4_regex = '%s%s%s%s%s%s' % ('^', rule1, rule1, rule1, rule2, '$')

    return bool(re.match(ipv4_regex, ip_addr))


def is_config_exist(cmp_cfg, test_cfg):
    """is configuration exist"""

    test_cfg_tmp = test_cfg + ' *$' + '|' + test_cfg + ' *\n'
    obj = re.compile(test_cfg_tmp)
    result = re.findall(obj, cmp_cfg)
    if not result:
        return False
    return True


class NetstreamExport(object):
    """Manange NetStream export"""

    def __init__(self, argument_spec):
        self.spec = argument_spec
        self.module = None
        self.__init_module__()

        # NetStream export configuration parameters
        self.type = self.module.params['type']
        self.source_ip = self.module.params['source_ip']
        self.host_ip = self.module.params['host_ip']
        self.host_port = self.module.params['host_port']
        self.host_vpn = self.module.params['host_vpn']
        self.version = self.module.params['version']
        self.as_option = self.module.params['as_option']
        self.bgp_netxhop = self.module.params['bgp_nexthop']
        self.state = self.module.params['state']

        self.commands = list()
        self.config = None
        self.exist_conf = dict()

        # state
        self.changed = False
        self.updates_cmd = list()
        self.results = dict()
        self.proposed = dict()
        self.existing = dict()
        self.end_state = dict()

    def __init_module__(self):
        """init module"""

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

    def cli_load_config(self, commands):
        """load config by cli"""

        if not self.module.check_mode:
            load_config(self.module, commands)

    def get_netstream_config(self):
        """get current netstream configuration"""

        flags = list()
        exp = " | inc ^netstream export"
        flags.append(exp)
        return get_config(self.module, flags)

    def get_existing(self):
        """get existing config"""

        self.existing = dict(type=self.type,
                             source_ip=self.exist_conf['source_ip'],
                             host_ip=self.exist_conf['host_ip'],
                             host_port=self.exist_conf['host_port'],
                             host_vpn=self.exist_conf['host_vpn'],
                             version=self.exist_conf['version'],
                             as_option=self.exist_conf['as_option'],
                             bgp_nexthop=self.exist_conf['bgp_netxhop'])

    def get_proposed(self):
        """get proposed config"""

        self.proposed = dict(type=self.type,
                             source_ip=self.source_ip,
                             host_ip=self.host_ip,
                             host_port=self.host_port,
                             host_vpn=self.host_vpn,
                             version=self.version,
                             as_option=self.as_option,
                             bgp_nexthop=self.bgp_netxhop,
                             state=self.state)

    def get_end_state(self):
        """get end config"""
        self.get_config_data()
        self.end_state = dict(type=self.type,
                              source_ip=self.exist_conf['source_ip'],
                              host_ip=self.exist_conf['host_ip'],
                              host_port=self.exist_conf['host_port'],
                              host_vpn=self.exist_conf['host_vpn'],
                              version=self.exist_conf['version'],
                              as_option=self.exist_conf['as_option'],
                              bgp_nexthop=self.exist_conf['bgp_netxhop'])

    def show_result(self):
        """show result"""

        self.results['changed'] = self.changed
        self.results['proposed'] = self.proposed
        self.results['existing'] = self.existing
        self.results['end_state'] = self.end_state
        if self.changed:
            self.results['updates'] = self.updates_cmd
        else:
            self.results['updates'] = list()

        self.module.exit_json(**self.results)

    def cli_add_command(self, command, undo=False):
        """add command to self.update_cmd and self.commands"""

        if undo and command.lower() not in ["quit", "return"]:
            cmd = "undo " + command
        else:
            cmd = command

        self.commands.append(cmd)          # set to device
        if command.lower() not in ["quit", "return"]:
            if cmd not in self.updates_cmd:
                self.updates_cmd.append(cmd)   # show updates result

    def config_nets_export_src_addr(self):
        """Configures the source address for the exported packets"""

        if is_ipv4_addr(self.source_ip):
            if self.type == 'ip':
                cmd = "netstream export ip source %s" % self.source_ip
            else:
                cmd = "netstream export vxlan inner-ip source %s" % self.source_ip
        else:
            if self.type == 'ip':
                cmd = "netstream export ip source ipv6 %s" % self.source_ip
            else:
                cmd = "netstream export vxlan inner-ip source ipv6 %s" % self.source_ip

        if is_config_exist(self.config, cmd):
            self.exist_conf['source_ip'] = self.source_ip
            if self.state == 'present':
                return
            else:
                undo = True
        else:
            if self.state == 'absent':
                return
            else:
                undo = False

        self.cli_add_command(cmd, undo)

    def config_nets_export_host_addr(self):
        """Configures the destination IP address and destination UDP port number"""

        if is_ipv4_addr(self.host_ip):
            if self.type == 'ip':
                cmd = 'netstream export ip host %s %s' % (self.host_ip, self.host_port)
            else:
                cmd = 'netstream export vxlan inner-ip host %s %s' % (self.host_ip, self.host_port)
        else:
            if self.type == 'ip':
                cmd = 'netstream export ip host ipv6 %s %s' % (self.host_ip, self.host_port)
            else:
                cmd = 'netstream export vxlan inner-ip host ipv6 %s %s' % (self.host_ip, self.host_port)

        if self.host_vpn:
            cmd += " vpn-instance %s" % self.host_vpn

        if is_config_exist(self.config, cmd):
            self.exist_conf['host_ip'] = self.host_ip
            self.exist_conf['host_port'] = self.host_port
            if self.host_vpn:
                self.exist_conf['host_vpn'] = self.host_vpn

            if self.state == 'present':
                return
            else:
                undo = True
        else:
            if self.state == 'absent':
                return
            else:
                undo = False

        self.cli_add_command(cmd, undo)

    def config_nets_export_vxlan_ver(self):
        """Configures the version for the exported packets carrying VXLAN flexible flow statistics"""

        cmd = 'netstream export vxlan inner-ip version 9'

        if is_config_exist(self.config, cmd):
            self.exist_conf['version'] = self.version

            if self.state == 'present':
                return
            else:
                undo = True
        else:
            if self.state == 'absent':
                return
            else:
                undo = False

        self.cli_add_command(cmd, undo)

    def config_nets_export_ip_ver(self):
        """Configures the version number of the exported packets carrying IPv4 flow statistics"""

        cmd = 'netstream export ip version %s' % self.version
        if self.version == '5':
            if self.as_option == 'origin':
                cmd += ' origin-as'
            elif self.as_option == 'peer':
                cmd += ' peer-as'
        else:
            if self.as_option == 'origin':
                cmd += ' origin-as'
            elif self.as_option == 'peer':
                cmd += ' peer-as'

            if self.bgp_netxhop == 'enable':
                cmd += ' bgp-nexthop'

        if cmd == 'netstream export ip version 5':
            cmd_tmp = "netstream export ip version"
            if is_config_exist(self.config, cmd_tmp):
                if self.state == 'present':
                    self.cli_add_command(cmd, False)
            else:
                self.exist_conf['version'] = self.version
            return

        if is_config_exist(self.config, cmd):
            self.exist_conf['version'] = self.version
            self.exist_conf['as_option'] = self.as_option
            self.exist_conf['bgp_netxhop'] = self.bgp_netxhop

            if self.state == 'present':
                return
            else:
                undo = True
        else:
            if self.state == 'absent':
                return
            else:
                undo = False

        self.cli_add_command(cmd, undo)

    def config_netstream_export(self):
        """configure netstream export"""

        if self.commands:
            self.cli_load_config(self.commands)
            self.changed = True

    def check_params(self):
        """Check all input params"""

        if not self.type:
            self.module.fail_json(msg='Error: The value of type cannot be empty.')

        if self.host_port:
            if not self.host_port.isdigit():
                self.module.fail_json(msg='Error: Host port is invalid.')
            if int(self.host_port) < 1 or int(self.host_port) > 65535:
                self.module.fail_json(msg='Error: Host port is not in the range from 1 to 65535.')

        if self.host_vpn:
            if self.host_vpn == '_public_':
                self.module.fail_json(
                    msg='Error: The host vpn name _public_ is reserved.')
            if len(self.host_vpn) < 1 or len(self.host_vpn) > 31:
                self.module.fail_json(msg='Error: The host vpn name length is not in the range from 1 to 31.')

        if self.type == 'vxlan' and self.version == '5':
            self.module.fail_json(msg="Error: When type is vxlan, version must be 9.")

        if self.type == 'ip' and self.version == '5' and self.bgp_netxhop == 'enable':
            self.module.fail_json(msg="Error: When type=ip and version=5, bgp_netxhop is not supported.")

        if (self.host_ip and not self.host_port) or (self.host_port and not self.host_ip):
            self.module.fail_json(msg="Error: host_ip and host_port must both exist or not exist.")

    def get_config_data(self):
        """get configuration commands and current configuration"""

        self.exist_conf['type'] = self.type
        self.exist_conf['source_ip'] = None
        self.exist_conf['host_ip'] = None
        self.exist_conf['host_port'] = None
        self.exist_conf['host_vpn'] = None
        self.exist_conf['version'] = None
        self.exist_conf['as_option'] = None
        self.exist_conf['bgp_netxhop'] = 'disable'

        self.config = self.get_netstream_config()

        if self.type and self.source_ip:
            self.config_nets_export_src_addr()

        if self.type and self.host_ip and self.host_port:
            self.config_nets_export_host_addr()

        if self.type == 'vxlan' and self.version == '9':
            self.config_nets_export_vxlan_ver()

        if self.type == 'ip' and self.version:
            self.config_nets_export_ip_ver()

    def work(self):
        """excute task"""

        self.check_params()
        self.get_proposed()
        self.get_config_data()
        self.get_existing()

        self.config_netstream_export()

        self.get_end_state()
        self.show_result()


def main():
    """main function entry"""

    argument_spec = dict(
        type=dict(required=True, type='str', choices=['ip', 'vxlan']),
        source_ip=dict(required=False, type='str'),
        host_ip=dict(required=False, type='str'),
        host_port=dict(required=False, type='str'),
        host_vpn=dict(required=False, type='str'),
        version=dict(required=False, type='str', choices=['5', '9']),
        as_option=dict(required=False, type='str', choices=['origin', 'peer']),
        bgp_nexthop=dict(required=False, type='str', choices=['enable', 'disable'], default='disable'),
        state=dict(choices=['absent', 'present'], default='present', required=False)
    )
    argument_spec.update(ce_argument_spec)
    netstream_export = NetstreamExport(argument_spec)
    netstream_export.work()


if __name__ == '__main__':
    main()
