#!/usr/bin/env python
#
# Nagios check to verify signal level of nanostation5
#
# Based on check_remoteneighbor
#
# By Richard van Mansom 
#

OK      = 15
WARNING = 10 
OFFSET  = -96

from collections import defaultdict
from pysnmp.entity.rfc3413.oneliner import cmdgen
from pysnmp.proto.rfc1902 import OctetString
from gettext import gettext as _

import argparse
import logging
import operator
import socket
import sys
import subprocess

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger()

class ERRNO():
  OK = 0
  WARNING = 1
  CRITICAL = 2
  UNKNOWN = 3
  


def snmpwalk(host, oid):
  # Failed: Script Exception - [<class 'pysnmp.error.PySnmpError'>] BULK PDU not implemented at <module 'pysnmp.proto.api.v1' from '/usr/local/lib/python2.7/site-packages/pysnmp-4.2.2rc5-py2.7.egg/pysnmp/proto/api/v1.pyc'>

  cmd="snmpwalk -Ov -v 1 -c public %s %s" % (host, oid)
  cmd=cmd.split()
  output = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()[0].split()
  try:
    if output[0] == "End":
      return int()
    return int(output[1])
  except:
    return int()

def getSignal(host):
  output = snmpwalk(host, '.1.3.6.1.4.1.14988.1.1.1.2.1.3.0.21.109.112.84')
  if not output: output = snmpwalk(host, '.1.3.6.1.4.1.14988.1.1.1.2.1.3')
  if not output: output = snmpwalk(host, '.1.3.6.1.4.1.14988.1.1.1.1.1.4')
  return output


def main(host):
  try:
    signal = getSignal(host)
    if signal == 0: return ("UNKNOWN: Signal: %s" % signal, ERRNO.UNKNOWN)
    signal2 = (OFFSET - signal) * -1
    if signal2 > OK : return ("OK: Signal: %s" % signal, ERRNO.OK)
    if signal2 > WARNING : return ("WARNING: Signal: %s" % signal, ERRNO.WARNING)
    return ("CRITICAL: Signal: %s" % signal, ERRNO.CRITICAL)

  except socket.gaierror as e:
    return ("Failed: SNMP for host cannot be queried - %s" % e, ERRNO.CRITICAL)
  except Exception as e:
    return ("Failed: Script Exception - [%s] %s" % (type(e),e), ERRNO.CRITICAL)



if __name__ == '__main__':
  class NagiosArgumentParser(argparse.ArgumentParser):
    ''' Like exit code 128 on errors'''
    def error(self, message):
      self.print_usage(sys.stderr)
      self.exit(128, _('%s: error: %s\n') % (self.prog, message))

  parser = NagiosArgumentParser(
    description='Nagios Check InterLinks via SNMP.',
    formatter_class=argparse.ArgumentDefaultsHelpFormatter)

  parser.add_argument('-g', dest='debug', action='store_true', default=False, help="Set logging to debug")
  parser.add_argument('host', action='store', type=str, help="Hostname to use")
  args = parser.parse_args()

  if args.debug:
    logger.setLevel(logging.DEBUG)

  (msg, errno) = main(args.host)
  sys.stdout.write(msg + "\n")
  sys.exit(errno)