#!/usr/bin/python
#
# gluster_host_service_handler.py -- Event handler which checks the
# status of defined services and accordingly changes the host status
#
# Copyright (C) 2014 Red Hat Inc
#
# This program 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 2
# of the License, or (at your option) any later version.
#
# This program 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 this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,USA
#

import sys
import datetime
import argparse
import json

import livestatus
from glusternagios import utils

SRVC_STATE_TYPE_SOFT = "SOFT"
SRVC_STATE_TYPE_HARD = "HARD"


def _writeNagiosCommand(cmdStr):
    with open("@nagioscommandfilepath@", "w") as f:
        f.write(cmdStr)


# Method to change the host status
def update_host_state(hostAddr, srvcName, statusCode):
    now = datetime.datetime.now()
    if statusCode == utils.PluginStatusCode.WARNING:
        cmdStr = "[%s] PROCESS_HOST_CHECK_RESULT;%s;%s;" \
                 "Host Status WARNING - " \
                 "Service(s) ['%s'] in CRITICAL state\n" \
                 % (now, hostAddr, utils.PluginStatusCode.OK, srvcName)
    else:
        cmdStr = "[%s] PROCESS_HOST_CHECK_RESULT;%s;%s;Host Status OK - " \
                 "Services in good health\n" \
                 % (now, hostAddr, utils.PluginStatusCode.OK)

    _writeNagiosCommand(cmdStr)


# Method to execute livestatus
def checkLiveStatus(hostAddr, srvc):
    cmd = "GET services\nColumns: state\nFilter: " \
          "description = %s\nFilter: host_address = %s" % (srvc, hostAddr)

    table = livestatus.readLiveStatus(cmd)

    if len(table) > 0 and len(table[0]) > 0:
        return int(table[0][0])
    else:
        return utils.PluginStatusCode.UNKNOWN


def _getHostMonitoringSrvcList():
    srvc_list = []
    with open("@hostmonitoringserviceslist@") as data_file:
        srvc_list = json.load(data_file)['serviceList']
    return srvc_list


# Method to change the host state to UP based on other service type status
def check_and_update_host_state_to_up(hostAddr, srvcName):
    finalState = utils.PluginStatusCode.OK
    for item in _getHostMonitoringSrvcList():
        if item != srvcName:
            finalState = finalState | checkLiveStatus(hostAddr, item)

    if finalState == utils.PluginStatusCode.OK:
        update_host_state(hostAddr, srvcName, utils.PluginStatusCode.OK)


# Main method
if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        usage='%(prog)s -s <State> -t <State Type>'
              ' -a <No of attempts> -l <Host Address>'
              ' -n <Service Name>')
    parser.add_argument(
        "-s",
        "--state",
        action="store",
        required=True,
        type=str,
        help="Current State of the service (CRITICAL/WARNING/OK/UNKNOWN)")
    parser.add_argument(
        "-t"
        "--statetype",
        action="store",
        required=True,
        type=str,
        help="State Type of the service (SOFT/HARD)")
    parser.add_argument(
        "-a",
        "--attempts",
        action="store",
        required=True,
        type=int,
        help="No of attempts")
    parser.add_argument(
        "-l",
        "--location",
        action="store",
        required=True,
        type=str,
        help="Address of the host")
    parser.add_argument(
        "-n",
        "--name",
        action="store",
        required=True,
        type=str,
        help="Service Name")

    args = parser.parse_args()

    # Swicth over the service state values and update state
    if args.state == utils.PluginStatus.CRITICAL \
            and args.t__statetype == SRVC_STATE_TYPE_HARD:
        print "Updating the host status to warning..."
        update_host_state(args.location,
                          args.name,
                          utils.PluginStatusCode.WARNING)
    elif args.state == utils.PluginStatusCode.OK:
        check_and_update_host_state_to_up(args.location, args.name)

    sys.exit(utils.PluginStatusCode.OK)