#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# Copyright (C) 2019 tribe29 GmbH - License: GNU General Public License v2
# This file is part of Checkmk (https://checkmk.com). It is subject to the terms and
# conditions defined in the file COPYING, which is part of this source code package.

# NOTE: Careful when replacing the *-import below with a more specific import. This can cause
# problems because it might remove variables from the check-context which are necessary for
# resolving legacy discovery results such as [("SUMMARY", "diskstat_default_levels")]. Furthermore,
# it might also remove variables needed for accessing discovery rulesets.
from cmk.base.check_legacy_includes.f5_bigip import *  # pylint: disable=wildcard-import,unused-wildcard-import

# Agent / MIB output
# see: 1.3.6.1.4.1.3375.2.2.5.1.2.1
# F5-BIGIP-LOCAL-MIB::ltmPoolName.              8.80.111.111.108.asci_encoded_str = Pool_NMA
# F5-BIGIP-LOCAL-MIB::ltmPoolMemberCnt.         8.80.111.111.108.95.78.77.65 = 2
# F5-BIGIP-LOCAL-MIB::ltmPoolActiveMemberCnt.   8.80.111.111.108.95.78.77.65 = 0

# warn, crit numbers of pool members
f5_bigip_pool_default_levels = (2, 1)


def parse_f5_bigip_pool(info):
    parsed = {}
    processed_member_info = False
    for block in info:
        if not block:
            continue

        # Member information
        if len(block[0]) == 3 and processed_member_info:
            break

        if len(block[0]) == 3:
            for line in block:
                parsed.setdefault(line[0], {"act_members": 0, "def_members": 0, "down_info": []})
                parsed[line[0]]["act_members"] += int(line[1])
                parsed[line[0]]["def_members"] += int(line[2])
            processed_member_info = True

        # Status information
        elif len(block[0]) == 6:
            for key, val in parsed.items():
                for line in block:
                    if key == line[0]:
                        val["down_info"].append(line)
    return parsed


def inventory_f5_bigip_pool(parsed):
    # inventorize all pools and their member count
    for item in parsed:
        if item != "":
            yield item, "f5_bigip_pool_default_levels"


def f5_bigip_pool_get_down_members(down_info):
    downs = []
    for line in down_info:
        if line[2] != "4" or line[3] != "4" or line[4] in ("2", "3", "4", "5"):
            if re.match(r"\/\S*\/\S*", line[5]):
                host = line[5].split("/")[2]
            else:
                host = line[5]
            downs.append(host + ":" + line[1])
    return downs


def check_f5_bigip_pool(item, params, parsed):
    warn, crit = params

    pool_info = parsed.get(item)
    if not pool_info:
        return

    pool_act_members = pool_info["act_members"]
    pool_def_members = pool_info["def_members"]
    message = "%d of %d members are up" % (pool_act_members, pool_def_members)
    state = 0
    if pool_act_members == pool_def_members or pool_act_members >= warn:
        state = 0
    elif pool_act_members < crit:
        state = 2
        message += " (warn/crit: %s/%s)" % (warn, crit)
    elif pool_act_members < warn:
        state = 1
        message += " (warn/crit: %s/%s)" % (warn, crit)

    if pool_act_members < pool_def_members:
        downs = f5_bigip_pool_get_down_members(pool_info["down_info"])
        if downs:
            message += ", down/disabled nodes: %s" % ", ".join(downs)
    return state, message


check_info["f5_bigip_pool"] = {
    "parse_function": parse_f5_bigip_pool,
    "check_function": check_f5_bigip_pool,
    "group": "f5_pools",
    "inventory_function": inventory_f5_bigip_pool,
    "service_description": "Load Balancing Pool %s",
    "snmp_info": [
        (
            ".1.3.6.1.4.1.3375.2.2.5.1.2.1",
            [
                1,  # ltmPoolEntry
                8,  # ltmPoolActiveMemberCnt
                23,  # ltmPoolMemberCnt
            ],
        ),
        (
            ".1.3.6.1.4.1.3375.2.2.5.3.2.1",
            [
                1,  # ltmPoolMemberPoolName
                4,  # ltmPoolMemberPort
                10,  # ltmPoolMemberMonitorState
                11,  # ltmPoolMemberMonitorStatus
                13,  # ltmPoolMemberSessionStatus
                19,  # ltmPoolMemberNodeName
            ],
        ),
    ],
    "snmp_scan_function": scan_f5_bigip,
}
