#!/bin/bash

# Centreon plugin to work with Pihole API

############ By @tips-of-mine ############
plugin_version="1.0"

##########################################

red=$'\033[1;31m'
yellow=$'\033[0;33m'
nc=$'\033[0m'

current_dira="$(pwd)"
current_dir="/usr/lib/centreon/plugins"

function info() {
	case "$1" in
		token)
			echo " "
			echo " ************************************************************************************************"
			echo " *"
			echo " * The file ${yellow}${api_token_file}${nc} does not exist or it's empty."
			echo " * You can get your token from the value ${yellow}WEBPASSWORD${nc} in the file ${yellow}/etc/pihole/setupVars.conf${nc}"
			echo " * Just put in the file ${yellow}${api_token_file}${nc} and that's it."
			echo " *"
			echo " * Example:"
			echo " *	centreon-engine@centreon # ${yellow}touch ${api_token_file}${nc}"
			echo " *	centreon-engine@centreon # ${yellow}echo 'PASTE_YOUR_TOKEN_HERE' >> ${api_token_file}${nc}"
			echo " *"
			echo " ************************************************************************************************"
			echo " "

			exit 1 ;
		;;
		usage)
			echo " "
			echo " ************************************************************************************************"
			echo " *"
			echo " * Instructions for use"
			echo " *"
			echo " ************************************************************************************************"
			echo " *"
			echo " * Usage $0 -h pihole_ipaddress -e [ ads || being || clients || queries || unique] || -s || -i || -q || -t "
			echo " *"
			echo " * -h (host) "
			echo " *	- ip address or fqdn name of the machine running Pi-Hole  "
			echo " *"
			echo " * -c (cache) "
			echo " *	- show cache "
			echo " *"
			echo " * -e (summary) "
			echo " * 	- ads     : Number and percentage of ads blocked. "
			echo " * 	- being   : Amount of blocked domain."
			echo " *	- clients : Number of clients using Pihole as their DNS server "
			echo " *	- domain  : Number of domain queries "
			echo " *	- queries : Number of DNS queries "
			echo " *"
			echo " * -f (forwarded) "
			echo " *	- show forwarded "
			echo " *"
			echo " * -r (reply) "
			echo " *	- show the status reply UNKNOWN, CNAME, IP, NODATA, NXDOMAIN "
			echo " *"
			echo " * -s (status) "
			echo " *	- show the status service (enable/disable) "
			echo " *"
			echo " * -q (querie) "
			echo " *	- queries by type AAAA, A, SOA, TXT, PTR, ANY, SRV, IPV4, IPV6 "
			echo " *"
			echo " * -t (top 10) "
			echo " *  - Show a TOP number of queries by host "
			echo " *"
			echo " * -v (information) "
			echo " *	- show the version of the plugin "
			echo " *"
			echo " ************************************************************************************************"
			echo " "

			exit 0 ;
		;;
		version)
			echo " "
			echo " ************************************************************************************************"
			echo " *"
			echo " * Plugin by @tips-of-mine https://git.tips-of-mine.fr/ - Version: ${plugin_version} "
			echo " *"
			echo " ************************************************************************************************"
			echo " "

			exit 0 ;
		;;
	esac
}

function ApiCall() {
	local obj=$1
	local token=$2

	pihole_api_tempfile="/tmp/pihole_api_${obj}.tmp"

	case $obj in
		"summary")
			pihole_api_output=$(curl "http://${pihole_ipadd}/admin/api.php?${obj}&auth=${token}" 2> /dev/null | sed 's/{/\n/g ; s/","/\n/g ; s/"//g' > ${pihole_api_tempfile})
		;;
		"status")
			pihole_api_output=$(curl "http://${pihole_ipadd}/admin/api.php?${obj}&auth=${token}" 2> /dev/null | sed 's/","/\n/g ; s/"//g' > ${pihole_api_tempfile})
		;;
		"getQueryTypes")
			pihole_api_output=$(curl "http://${pihole_ipadd}/admin/api.php?${obj}&auth=${token}" 2> /dev/null | sed "s,),,g ; s,(,,g ; s/,\"/\n/g ; s/\"//g" > ${pihole_api_tempfile})
		;;
		"getQuerySources")
			pihole_api_output=$(curl "http://${pihole_ipadd}/admin/api.php?${obj}&auth=${token}" 2> /dev/null | sed 's,{"top_sources":{",,g ; s/,"/\n/g ; s/"//g ; s/}//g ; s/|/:/g' > ${pihole_api_tempfile})
	esac
}

function GetApiToken() {
	# Default token file location
	api_token_file="${current_dir}/pihole-api.token"

	# If the file does not exist
	if [ ! -f ${api_token_file} ]; then
		echo " "
		echo " ************************************************************************************************"
		echo " *"
		echo " * ${red}The file ${api_token_file} does not exist ${nc}"
		echo " *"
		echo " ************************************************************************************************"
		echo " ";

		info token
	else
		export api_token=$(cat ${api_token_file})
		# If the the api_token var is NULL because the file is empty (?)
		if [ -z ${api_token} ]; then
			echo " "
			echo " ************************************************************************************************"
			echo " *"
			echo " * ${red}The file ${api_token_file} exists, but it is empty ${nc}"
			echo " *"
			echo " ************************************************************************************************"
			echo " ";

			info token
		fi
	fi
}

function functSummary() {
	# This function requires a token
	GetApiToken

	# The summary option passed
	ApiCall "summary" "${api_token}"

	case "${summary_opt}" in
		ads)
			ads_percentage_today=$(cat ${pihole_api_tempfile} | grep ads_percentage_today | cut -f2 -d":")
			ads_blocked_today=$(cat ${pihole_api_tempfile} | grep ads_blocked_today | cut -f2 -d":")
			echo "ADS blocked today : ${ads_blocked_today}, Percentage = ${ads_percentage_today} % | 'TotalADS'=${ads_blocked_today} 'Percentage'=${ads_percentage_today}%"
		;;
		being)
			domains_being_blocked=$(cat ${pihole_api_tempfile} | grep domains_being_blocked | cut -f2 -d":")
			echo "Domains blocked : ${domains_being_blocked} | 'Blocked'=${domains_being_blocked}"
		;;
		clients)
			unique_clients=$(cat ${pihole_api_tempfile} | grep unique_clients | cut -f2 -d":")
			clients_ever_seen=$(cat ${pihole_api_tempfile} | grep clients_ever_seen | cut -f2 -d":")
			echo "${unique_clients} Hosts up, Total ${clients_ever_seen} | 'Hosts'=${unique_clients} 'TotalHosts'=${clients_ever_seen}"
		;;
		domain)
			unique_domains=$(cat ${pihole_api_tempfile} | grep unique_domains | cut -f2 -d":")
			echo "Queries domain : ${unique_domains} | 'QueryDomain'=${unique_domains}"
		;;
		queries)
			dns_queries_today=$(cat ${pihole_api_tempfile} | grep dns_queries_today | cut -f2 -d":")
			dns_queries_all_types=$(cat ${pihole_api_tempfile} | grep dns_queries_all_types | cut -f2 -d":")
			echo "DNS queries today : ${dns_queries_today}, queries all type : ${dns_queries_all_types} | 'DnsTotalToday'=${dns_queries_today} 'DnsAllType'=${dns_queries_all_types}"
		;;
		*)
			echo " "
			echo " ************************************************************************************************"
			echo " *"
			echo " * ${red}Incorrect arugment > ${summary_opt} < for the option -s ${nc}"
			echo " *"
			echo " ************************************************************************************************"
			echo " ";

			info "usage"

			exit 1 ;
		;;
	esac
}

function functCache() {
	# This function requires a token
	GetApiToken

	# Calling the api
	ApiCall "summary" "${api_token}"

	#
	queries_cached=$(cat ${pihole_api_tempfile} | grep -io "queries_cached:.*" | cut -f2 -d":" | sed 's/}//g')

	#
	echo "Use cache ${queries_cached} | 'cache'=${queries_cached} "
}

function functforwarded() {
	# This function requires a token
	GetApiToken

	# Calling the api
	ApiCall "summary" "${api_token}"

	#
	queries_forwarded=$(cat ${pihole_api_tempfile} | grep -io "queries_forwarded:.*" | cut -f2 -d":" | sed 's/}//g')

	#
	echo "Use forwarded ${queries_forwarded} | 'forwarded'=${queries_forwarded} "
}

function functStatus() {
	# This function requires a token
	GetApiToken

	# Calling the api
	ApiCall "status" "${api_token}"

	#
	status=$(cat ${pihole_api_tempfile} | grep -io "status:.*" | cut -f2 -d":" | sed 's/}//g')

	#
	if [[ ${status} == "enabled" ]]; then
		echo "OK - Status Pi-Hole is ${status} | 'enabled'=1, 'disabled'=0 "

		exit 0;
	elif [[ ${status} == "disabled" ]]; then
		echo "WARNING - Status Pi-Hole is ${status} | 'enabled'=0, 'disabled'=1 "

		exit 1;
	else
		echo "UNKNOWN - Status Pi-Hole is ${status} | 'enabled'=0, 'disabled'=0 "

		exit 3;
	fi
}

function functGetReply() {
	# This function requires a token
	GetApiToken

	# Calling the api
	ApiCall "summary" "${api_token}"

	# Local vars for query types
	local reply_UNKNOWN=$(cat ${pihole_api_tempfile} | grep reply_UNKNOWN | cut -f2 -d":")
	local reply_NODATA=$(cat ${pihole_api_tempfile} | grep reply_NODATA | cut -f2 -d":")
	local reply_NXDOMAIN=$(cat ${pihole_api_tempfile} | grep reply_NXDOMAIN | cut -f2 -d":")
	local reply_CNAME=$(cat ${pihole_api_tempfile} | grep reply_CNAME | cut -f2 -d":")
	local reply_IP=$(cat ${pihole_api_tempfile} | grep reply_IP | cut -f2 -d":")
	local reply_DOMAIN=$(cat ${pihole_api_tempfile} | grep reply_DOMAIN | cut -f2 -d":")

	texte="'UNKNOWN'=${reply_UNKNOWN}, 'NODATA'=${reply_NODATA}, 'NXDOMAIN'=${reply_NXDOMAIN}, 'CNAME'=${reply_CNAME}, 'IP'=${reply_IP}, 'DOMAIN'=${reply_DOMAIN}"
	datatexte="'UNKNOWN'=${reply_UNKNOWN}, 'NODATA'=${reply_NODATA}, 'NXDOMAIN'=${reply_NXDOMAIN}, 'CNAME'=${reply_CNAME}, 'IP'=${reply_IP}, 'DOMAIN'=${reply_DOMAIN}"

	echo "Reply type ${texte} | ${datatexte}"
}

function functGetQueryTypes() {
	# This function requires a token
	GetApiToken

	# Calling the api
	ApiCall "getQueryTypes" "${api_token}"

	# Local vars for query types
	local ipv4=$(cat ${pihole_api_tempfile} | grep -io "ipv4:.*" | cut -f2 -d":")
	local ipv6=$(cat ${pihole_api_tempfile} | grep -io "ipv6:.*" | cut -f2 -d":")
	local any=$(cat ${pihole_api_tempfile} | grep -io "any:.*" | cut -f2 -d":")
	local srv=$(cat ${pihole_api_tempfile} | grep -io "srv:.*" | cut -f2 -d":")
	local soa=$(cat ${pihole_api_tempfile} | grep -io "soa:.*" | cut -f2 -d":")
	local ptr=$(cat ${pihole_api_tempfile} | grep -xi "ptr:.*"  | cut -f2 -d":")
	local naptr=$(cat ${pihole_api_tempfile} | grep -io "naptr:.*" | cut -f2 -d":")
	local txt=$(cat ${pihole_api_tempfile} | grep -io "txt:.*" | sed 's,},,g' | cut -f2 -d":")
	local mx=$(cat ${pihole_api_tempfile} | grep -io "mx:.*" | sed 's,},,g' | cut -f2 -d":")
	local ds=$(cat ${pihole_api_tempfile} | grep -io "ds:.*" | sed 's,},,g' | cut -f2 -d":")
	local rrsig=$(cat ${pihole_api_tempfile} | grep -io "rrsig:.*" | sed 's,},,g' | cut -f2 -d":")
	local dnskey=$(cat ${pihole_api_tempfile} | grep -io "ns:.*" | sed 's,},,g' | cut -f2 -d":")
	local ns=$(cat ${pihole_api_tempfile} | grep -io "ns:.*" | sed 's,},,g' | cut -f2 -d":")
	local other=$(cat ${pihole_api_tempfile} | grep -io "other:.*" | sed 's,},,g' | cut -f2 -d":")
	local svcb=$(cat ${pihole_api_tempfile} | grep -io "svcb:.*" | sed 's,},,g' | cut -f2 -d":")

	texte="'IPV4'=${ipv4}, 'IPV6'=${ipv6}, 'ANY'=${any}, 'SRV'=${srv}, 'SOA'=${soa}, 'PTR'=${ptr}, 'NAPTR'=${naptr}, 'TXT'=${txt}, 'MX'=${mx}, 'DS'=${ds}, 'RRSIG'=${rrsig}, 'DNSKEY'=${dnskey}, 'NS'=${ns}, 'OTHER'=${other}, 'SVCB'=${svcb}"
	datatexte="'IPV4'=${ipv4}, 'IPV6'=${ipv6}, 'ANY'=${any}, 'SRV'=${srv}, 'SOA'=${soa}, 'PTR'=${ptr}, 'NAPTR'=${naptr}, 'TXT'=${txt}, 'MX'=${mx}, 'DS'=${ds}, 'RRSIG'=${rrsig}, 'DNSKEY'=${dnskey}, 'NS'=${ns}, 'OTHER'=${other}, 'SVCB'=${svcb}"

	echo "Number of queries by type ${texte} | ${datatexte}"
}

function functGetQuerySources() {
	# This function requires a token
	GetApiToken

	# Calling the api
	ApiCall "getQuerySources" "${api_token}"

	while read line; do
		check_columns=$(echo $line | sed 's,:, ,g' | wc -w)
		host_name=$(echo $line | cut -f1 -d":")

		if [[ "${check_columns}" == "3" ]]; then
			columns="3"
		elif [[ "${check_columns}" == "2" ]]; then
			columns="2"
		else
			echo "Error formatting the list"
			echo " "

			exit 1;
		fi

		host_queries=$(echo ${line} | cut -f${columns} -d":")

		if [ -z "${host_queries}" ]; then host_queries="0"; fi

		texte="${texte} ${host_name}=${host_queries}\n"
		datatexte="${datatexte} ${host_name}=${host_queries}"
	done < ${pihole_api_tempfile}

	echo -e "Top hosts by queries :\n${texte}|${datatexte}"
}

# Display if there is no argument
if [ $# -eq 0 ]; then
	info "usage"

	exit 1;
fi

# The options passed by the user
while getopts "h:e:cfqrstv" opt; do
	case "$opt" in
		h )
			pihole_ipadd=${OPTARG}		;;
		c )
		e )
			summary_selected="y"
			summary_opt=${OPTARG}		;;
		f )
			query_forwarded="y"			;;
		q )
			query_type_selected="y" 	;;
		r )
			query_type_reply="y" 		;;
		s )
			status="y" 					;;
		t )
			query_sources_selected="y"	;;
		v )
			info "version"
			exit 0 ;;
		\?)
			echo " "
			echo " ************************************************************************************************"
			echo " *"
			echo " * ${red}Invalid option. -${OPTARG} ${nc}"
			echo " *"
			echo " * use -h to get help "
			echo " *"
			echo " ************************************************************************************************"
			echo " "

			exit 1 ;;
	esac
done

# The values passed by the user
if [ -z ${pihole_ipadd} ]; then
	echo " "
	echo " ************************************************************************************************"
	echo " *"
	echo " * ${red}Please enter the Pihole IP address as follow: -h pihole_ipaddress ${nc}"
	echo " *"
	echo " ************************************************************************************************"
	echo " ";

	exit 1;
else
	if [[ "${summary_selected}" == "y" ]]; then
		# Calling the summary function
		functSummary

		exit 0;
	elif [[ "${query_cached}" == "y" ]]; then
		# Calling the status Cache
		functCache

		exit 0;
	elif [[ "${status}" == "y" ]]; then
		# Calling the status service
		functStatus

		exit 0;
	elif [[ "${query_forwarded}" == "y" ]]; then
		# Calling the status forwarded
		functforwarded

		exit 0;
	elif [[ "${query_type_selected}" == "y" ]]; then
		# Calling the Query Types funct
		functGetQueryTypes

		exit 0;
	elif [[ "${query_sources_selected}" == "y" ]]; then
		# Calling the Query Source funct
		functGetQuerySources

		exit 0;
	elif [[ "${query_type_reply}" == "y" ]]; then
		# Calling the Query Reply funct
		functGetReply

		exit 0;
	else
		info "usage"
	fi

	# Just delete the temp file
	#rm -f ${pihole_api_tempfile}
fi