#!/usr/bin/env python3
import argparse
import zulip

from typing import List, Text, Dict, Any

VERSION = "0.9"
# Nagios passes the notification details as command line options.
# In Nagios, "output" means "first line of output", and "long
# output" means "other lines of output".
parser = zulip.add_default_arguments(argparse.ArgumentParser())  # type: argparse.ArgumentParser
parser.add_argument('--output', default='')
parser.add_argument('--long-output', default='')
parser.add_argument('--stream', default='nagios')
parser.add_argument('--config', default='/etc/nagios3/zuliprc')
for opt in ('type', 'host', 'service', 'state'):
    parser.add_argument('--' + opt)
opts = parser.parse_args()

client = zulip.Client(config_file=opts.config,
                      client="ZulipNagios/" + VERSION)  # type: zulip.Client

msg = dict(type='stream', to=opts.stream)  # type: Dict[str, Any]

# Set a subject based on the host or service in question.  This enables
# threaded discussion of multiple concurrent issues, and provides useful
# context when narrowed.
#
# We send PROBLEM and RECOVERY messages to the same subject.
if opts.service is None:
    # Host notification
    thing = 'host'  # type: Text
    msg['subject'] = 'host %s' % (opts.host,)
else:
    # Service notification
    thing = 'service'
    msg['subject'] = 'service %s on %s' % (opts.service, opts.host)

if len(msg['subject']) > 60:
    msg['subject'] = msg['subject'][0:57].rstrip() + "..."
# e.g. **PROBLEM**: service is CRITICAL
msg['content'] = '**%s**: %s is %s' % (opts.type, thing, opts.state)

# The "long output" can contain newlines represented by "\n" escape sequences.
# The Nagios mail command uses /usr/bin/printf "%b" to expand these.
# We will be more conservative and handle just this one escape sequence.
output = (opts.output + '\n' + opts.long_output.replace(r'\n', '\n')).strip()  # type: Text
if output:
    # Put any command output in a code block.
    msg['content'] += ('\n\n~~~~\n' + output + "\n~~~~\n")

client.send_message(msg)