#!/usr/bin/env bash

#set -o errexit
#set -o pipefail

#add route unix-shell avicontrol
gw="10.110.XX.XX"
IFACE='eth0'
ROUTE_FC=8
LOG="logger -t routeupd"
GREP='grep --color=never'

is_ip() {
	echo $1 | ${GREP} '^[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}$' > /dev/null
	return $?
}

run() {
	#res=$(eval $1 2>&1)
	echo $1
	if [ $? != 0 ]
	then
		$LOG "Error run route cmd: $1"
		return 1
	else
		return 0
	fi
}

net_gt() {
	local n1=$1
	local m1=$2
	local n2=$3
	local m2=$4
	if [[ "$n1" = "$n2" ]]
	then
		if [[ "$m1" > "$m2" ]]
		then
			return 0
		else
			return 1
		fi
	elif [[ "$n1" > "$n2" ]]
	then
		return 0
	else
		return 1
	fi
}

main() {
	# read current routes
	cur_array=( $(route -n | ${GREP} ' ${IFACE}$' | ${GREP} " ${gw} " | sort -r) )
	if [ $? != 0 ]
	then
		$LOG "Error get routes"
		exit 1
	fi
	cur_count=$((${#cur_array[*]}/${ROUTE_FC}))
	$LOG "Current route count $cur_count"
	cn=()
	cm=()
	for ((i=0; i <cur_count> /dev/null)
	then
		$LOG 'Download status ok'
	else
		$LOG "Error loading route status: $net"
		exit 1
	fi
	net=()
	mask=()
	for ((i=0; i < $count; i++))
	do
		local n=${array[$i*2+1]}
		local m=${array[$i*2+2]}
		if is_ip $n && is_ip $m
		then
			net[${#net[*]}]=$n
			mask[${#mask[*]}]=$m
		else
			$LOG "Error loaded net: $n mask: $m"
		fi
	done
	
	route_add_count=0
	route_del_count=0
	route_remain_count=0
	ci=0
	for ((i=0; i < $count; i++))
	do
		local n="${net[$i]}"
		local m="${mask[$i]}"
		while (( $ci < $cur_count )) &&
			net_gt "${cn[$ci]}" "${cm[$ci]}" "$n" "$m"
		do
			cmd="route del -net ${cn[$ci]} netmask ${cm[$ci]} gw $gw"
			if run "$cmd"
			then
				let route_del_count++
			fi
			let ci++
		done
		if (( $ci == $cur_count )) ||
			[[ "${cn[$ci]}" != "$n" ]] || [[ "${cm[$ci]}" != "$m" ]]
		then
			cmd="route add -net $n netmask $m gw $gw" 
			if run "$cmd"
			then
				let route_add_count++
			fi
		elif [[ "${cn[$ci]}" = "$n" ]] && [[ "${cm[$ci]}" = "$m" ]]
		then
			let ci++
			let route_remain_count++
		fi
	done
	# delete remain current routes
	while (( $ci < $cur_count ))
	do
		cmd="route del -net ${cn[$ci]} netmask ${cm[$ci]} gw $gw"
		if run "$cmd"
		then
			let route_del_count++
		fi
		let ci++
	done
	$LOG "Add: $route_add_count, Del: $route_del_count, Remain: $route_remain_count"
}

main