#!/bin/bash

ECHO=
IP_BASE_ADDR=10.1
IP6_BASE_ADDR=fd00:0:1

CMD=$1
LOW=$2
HIGH=$3
SIDE=$4

if [[ $CMD = add ]]; then
	for n in high medium low; do
		unshare -n ip netns add $n
		ip netns exec $n ip link set up lo
	done
fi

for n in $(seq $LOW $HIGH); do
	if [[ $CMD = add ]]; then
		$ECHO ip netns exec medium ip link add br${n} type bridge
		$ECHO ip netns exec medium ip link set br${n} up
		$ECHO ip netns exec medium ip addr add ${IP_BASE_ADDR}.${n}.2/24 broadcast ${IP_BASE_ADDR}.${n}.255 dev br${n}
		$ECHO ip netns exec medium ip addr add ${IP6_BASE_ADDR}:$((100 + $n))::2/64 dev br${n}

		ip=1
		for p in high low; do
			$ECHO ip netns exec medium ip link add eth${n}.$p type veth peer name eth${n}
			$ECHO ip netns exec medium ip link set eth${n}.$p master br${n}
			$ECHO ip netns exec medium ip link set eth${n}.$p up

			$ECHO ip netns exec medium ip link set eth${n} netns $p

			$ECHO ip netns exec $p ip link set eth${n} up
			$ECHO ip netns exec $p ip addr add ${IP_BASE_ADDR}.${n}.${ip}/24 broadcast ${IP_BASE_ADDR}.${n}.255 dev eth${n}
			$ECHO ip netns exec $p ip addr add ${IP6_BASE_ADDR}:$((100 + $n))::${ip}/64 dev eth${n}

			((ip += 2))
		done

		$ECHO ip netns exec medium ip link add eth${n} type dummy
		$ECHO ip netns exec medium ip link set eth${n} master br${n}
		$ECHO ip netns exec medium ip link set up eth${n}
	elif [[ $CMD = del ]]; then
		$ECHO ip netns exec medium ip link del eth${n}.low
		$ECHO ip netns exec medium ip link del eth${n}.high
		$ECHO ip netns exec medium ip link del eth${n}
		$ECHO ip netns exec medium ip link del br${n}
	elif [[ $CMD = remake ]]; then
		p=$SIDE
		[[ $p = low ]] && ip=3 || ip=1

		$ECHO ip netns exec medium ip link add eth${n}.$p type veth peer name eth${n}
		$ECHO ip netns exec medium ip link set eth${n}.$p master br${n}
		$ECHO ip netns exec medium ip link set eth${n}.$p up

		$ECHO ip netns exec medium ip link set eth${n} netns $p

		$ECHO ip netns exec $p ip addr add ${IP_BASE_ADDR}.${n}.${ip}/24 broadcast ${IP_BASE_ADDR}.${n}.255 dev eth${n}
		$ECHO ip netns exec $p ip addr add ${IP6_BASE_ADDR}:$((100 + $n))::${ip}/64 dev eth${n}

		$ECHO ip netns exec $p ip link set eth${n} up
	else
		echo Unknown command $CMD
	fi
done
