#!/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/>.
#
from __future__ import absolute_import, division, print_function

__metaclass__ = type


DOCUMENTATION = """
module: nxos_bfd_global
extends_documentation_fragment:
- cisco.nxos.nxos
short_description: Bidirectional Forwarding Detection (BFD) global-level configuration
description:
- Manages Bidirectional Forwarding Detection (BFD) global-level configuration.
version_added: 1.0.0
author:
- Chris Van Heuveln (@chrisvanheuveln)
notes:
- Tested against NXOSv 9.2(2)
- Unsupported for Cisco MDS
- BFD global will automatically enable 'feature bfd' if it is disabled.
- BFD global does not have a 'state' parameter. All of the BFD commands are unique
  and are defined if 'feature bfd' is enabled.
options:
  echo_interface:
    description:
    - Loopback interface used for echo frames.
    - Valid values are loopback interface name or 'deleted'.
    - Not supported on N5K/N6K
    required: false
    type: str
  echo_rx_interval:
    description:
    - BFD Echo receive interval in milliseconds.
    required: false
    type: int
  interval:
    description:
    - BFD interval timer values.
    - Value must be a dict defining values for keys (tx, min_rx, and multiplier)
    required: false
    type: dict
  slow_timer:
    description:
    - BFD slow rate timer in milliseconds.
    required: false
    type: int
  startup_timer:
    description:
    - BFD delayed startup timer in seconds.
    - Not supported on N5K/N6K/N7K
    required: false
    type: int
  ipv4_echo_rx_interval:
    description:
    - BFD IPv4 session echo receive interval in milliseconds.
    required: false
    type: int
  ipv4_interval:
    description:
    - BFD IPv4 interval timer values.
    - Value must be a dict defining values for keys (tx, min_rx, and multiplier).
    required: false
    type: dict
  ipv4_slow_timer:
    description:
    - BFD IPv4 slow rate timer in milliseconds.
    required: false
    type: int
  ipv6_echo_rx_interval:
    description:
    - BFD IPv6 session echo receive interval in milliseconds.
    required: false
    type: int
  ipv6_interval:
    description:
    - BFD IPv6 interval timer values.
    - Value must be a dict defining values for keys (tx, min_rx, and multiplier).
    required: false
    type: dict
  ipv6_slow_timer:
    description:
    - BFD IPv6 slow rate timer in milliseconds.
    required: false
    type: int
  fabricpath_interval:
    description:
    - BFD fabricpath interval timer values.
    - Value must be a dict defining values for keys (tx, min_rx, and multiplier).
    required: false
    type: dict
  fabricpath_slow_timer:
    description:
    - BFD fabricpath slow rate timer in milliseconds.
    required: false
    type: int
  fabricpath_vlan:
    description:
    - BFD fabricpath control vlan.
    required: false
    type: int
"""
EXAMPLES = """
- cisco.nxos.nxos_bfd_global:
    echo_interface: Ethernet1/2
    echo_rx_interval: 50
    interval:
      tx: 50
      min_rx: 50
      multiplier: 4
"""

RETURN = """
cmds:
    description: commands sent to the device
    returned: always
    type: list
    sample: ["bfd echo-interface loopback1", "bfd slow-timer 2000"]
"""


import re
from ansible_collections.cisco.nxos.plugins.module_utils.network.nxos.nxos import (
    NxosCmdRef,
)
from ansible_collections.cisco.nxos.plugins.module_utils.network.nxos.nxos import (
    nxos_argument_spec,
)
from ansible_collections.cisco.nxos.plugins.module_utils.network.nxos.nxos import (
    load_config,
)
from ansible.module_utils.basic import AnsibleModule

BFD_CMD_REF = """
# The cmd_ref is a yaml formatted list of module commands.
# A leading underscore denotes a non-command variable; e.g. _template.
# BFD does not have convenient json data so this cmd_ref uses raw cli configs.
---
_template: # _template holds common settings for all commands
  # Enable feature bfd if disabled
  feature: bfd
  # Common get syntax for BFD commands
  get_command: show run bfd all | incl '^(no )*bfd'

echo_interface:
  kind: str
  getval: (no )*bfd echo-interface *(\\S+)*$
  setval: 'bfd echo-interface {0}'
  default: ~

echo_rx_interval:
  _exclude: ['N5K', 'N6K']
  kind: int
  getval: bfd echo-rx-interval (\\d+)$
  setval: bfd echo-rx-interval {0}
  default: 50
  N3K:
    default: 250

interval:
  kind: dict
  getval: bfd interval (?P<tx>\\d+) min_rx (?P<min_rx>\\d+) multiplier (?P<multiplier>\\d+)
  setval: bfd interval {tx} min_rx {min_rx} multiplier {multiplier}
  default: &def_interval
    tx: 50
    min_rx: 50
    multiplier: 3
  N3K:
    default: &n3k_def_interval
      tx: 250
      min_rx: 250
      multiplier: 3

slow_timer:
  kind: int
  getval: bfd slow-timer (\\d+)$
  setval: bfd slow-timer {0}
  default: 2000

startup_timer:
  _exclude: ['N5K', 'N6K', 'N7K']
  kind: int
  getval: bfd startup-timer (\\d+)$
  setval: bfd startup-timer {0}
  default: 5

# IPv4/IPv6 specific commands
ipv4_echo_rx_interval:
  _exclude: ['N5K', 'N6K']
  kind: int
  getval: bfd ipv4 echo-rx-interval (\\d+)$
  setval: bfd ipv4 echo-rx-interval {0}
  default: 50
  N3K:
    default: 250

ipv4_interval:
  _exclude: ['N5K', 'N6K']
  kind: dict
  getval: bfd ipv4 interval (?P<tx>\\d+) min_rx (?P<min_rx>\\d+) multiplier (?P<multiplier>\\d+)
  setval: bfd ipv4 interval {tx} min_rx {min_rx} multiplier {multiplier}
  default: *def_interval
  N3K:
    default: *n3k_def_interval

ipv4_slow_timer:
  _exclude: ['N5K', 'N6K']
  kind: int
  getval: bfd ipv4 slow-timer (\\d+)$
  setval: bfd ipv4 slow-timer {0}
  default: 2000

ipv6_echo_rx_interval:
  _exclude: ['N35', 'N5K', 'N6K']
  kind: int
  getval: bfd ipv6 echo-rx-interval (\\d+)$
  setval: bfd ipv6 echo-rx-interval {0}
  default: 50
  N3K:
    default: 250

ipv6_interval:
  _exclude: ['N35', 'N5K', 'N6K']
  kind: dict
  getval: bfd ipv6 interval (?P<tx>\\d+) min_rx (?P<min_rx>\\d+) multiplier (?P<multiplier>\\d+)
  setval: bfd ipv6 interval {tx} min_rx {min_rx} multiplier {multiplier}
  default: *def_interval
  N3K:
    default: *n3k_def_interval

ipv6_slow_timer:
  _exclude: ['N35', 'N5K', 'N6K']
  kind: int
  getval: bfd ipv6 slow-timer (\\d+)$
  setval: bfd ipv6 slow-timer {0}
  default: 2000

# Fabricpath Commands
fabricpath_interval:
  _exclude: ['N35', 'N3K', 'N9K']
  kind: dict
  getval: bfd fabricpath interval (?P<tx>\\d+) min_rx (?P<min_rx>\\d+) multiplier (?P<multiplier>\\d+)
  setval: bfd fabricpath interval {tx} min_rx {min_rx} multiplier {multiplier}
  default: *def_interval

fabricpath_slow_timer:
  _exclude: ['N35', 'N3K', 'N9K']
  kind: int
  getval: bfd fabricpath slow-timer (\\d+)$
  setval: bfd fabricpath slow-timer {0}
  default: 2000

fabricpath_vlan:
  _exclude: ['N35', 'N3K', 'N9K']
  kind: int
  getval: bfd fabricpath vlan (\\d+)$
  setval: bfd fabricpath vlan {0}
  default: 1
"""


def reorder_cmds(cmds):
    """
    There is a bug in some image versions where bfd echo-interface and
    bfd echo-rx-interval need to be applied last for them to nvgen properly.
    """
    regex1 = re.compile(r"^bfd echo-interface")
    regex2 = re.compile(r"^bfd echo-rx-interval")
    filtered_cmds = [i for i in cmds if not regex1.match(i)]
    filtered_cmds = [i for i in filtered_cmds if not regex2.match(i)]
    echo_int_cmd = [i for i in cmds if regex1.match(i)]
    echo_rx_cmd = [i for i in cmds if regex2.match(i)]
    filtered_cmds.extend(echo_int_cmd)
    filtered_cmds.extend(echo_rx_cmd)

    return filtered_cmds


def main():
    argument_spec = dict(
        echo_interface=dict(required=False, type="str"),
        echo_rx_interval=dict(required=False, type="int"),
        interval=dict(required=False, type="dict"),
        slow_timer=dict(required=False, type="int"),
        startup_timer=dict(required=False, type="int"),
        ipv4_echo_rx_interval=dict(required=False, type="int"),
        ipv4_interval=dict(required=False, type="dict"),
        ipv4_slow_timer=dict(required=False, type="int"),
        ipv6_echo_rx_interval=dict(required=False, type="int"),
        ipv6_interval=dict(required=False, type="dict"),
        ipv6_slow_timer=dict(required=False, type="int"),
        fabricpath_interval=dict(required=False, type="dict"),
        fabricpath_slow_timer=dict(required=False, type="int"),
        fabricpath_vlan=dict(required=False, type="int"),
    )
    argument_spec.update(nxos_argument_spec)
    module = AnsibleModule(
        argument_spec=argument_spec, supports_check_mode=True
    )
    warnings = list()

    cmd_ref = NxosCmdRef(module, BFD_CMD_REF)
    cmd_ref.get_existing()
    cmd_ref.get_playvals()
    cmds = reorder_cmds(cmd_ref.get_proposed())

    result = {
        "changed": False,
        "commands": cmds,
        "warnings": warnings,
        "check_mode": module.check_mode,
    }
    if cmds:
        result["changed"] = True
        if not module.check_mode:
            load_config(module, cmds)

    module.exit_json(**result)


if __name__ == "__main__":
    main()
