#!/usr/bin/env bash

#
# nagios-force-check(1) -- Force an immediate check of a nominated host or
# service.
#
#     $ nfc <host>[/<service>]
#
# Author: Tom Ryder <tom@sanctum.geek.nz>
# Copyright: 2014 Sanctum
#

# Name self
self=nagios-force-check

# Usage printing function
usage() {
    printf 'USAGE: %s [-n] <host[/service]>\n' "$self"
}

# Handle options, just -h help at the moment
OPTIND=1
while getopts 'h' opt ; do
    case "$opt" in
        h)
            usage
            exit 0
            ;;
        '?')
            usage >&2
            exit 1
            ;;
    esac
done
shift "$((OPTIND-1))"

# Bail if no arguments left; we need at least the host/service name
if ! (($#)) ; then
    usage >&2
    exit 1
fi

# Define relatively fixed/guaranteed fields for Nagios command; note that the
# comment has a default of 'no comment given'
now=$(date +%s)
spec=$1
cmdfile=${NAGCMD_FILE:-/usr/local/nagios/var/rw/nagios.cmd}

# If a service name is specified after a slash, figure that out
if [[ $spec == */* ]] ; then
    host=${spec%/*}
    service=${spec##*/}
else
    host=$spec
    service=
fi

# Write command and print message if it fails; succeed silently
declare -a cmds
if [[ $service ]] ; then
    cmds=("${cmds[@]}" "$(printf '[%lu] SCHEDULE_FORCED_SVC_CHECK;%s;%s;%lu' \
        "$now" "$host" "$service" "$now")")
else
    cmds=("${cmds[@]}" "$(printf '[%lu] SCHEDULE_FORCED_HOST_CHECK;%s;%lu' \
        "$now" "$host" "$now")")
    cmds=("${cmds[@]}" "$(printf '[%lu] SCHEDULE_HOST_SVC_CHECKS;%s;%lu' \
        "$now" "$host" "$now")")
fi

# Attempt to write command to file
for cmd in "${cmds[@]}" ; do
    if ! printf '%s\n' "$cmd" >> "$cmdfile" ; then
        printf '%s: Failed to write command to file\n' "$self" >&2
        exit 1
    fi
done