#!/bin/sh

set -e

[ -n "$VERBOSE" ] && set -x

is_vlan() {
	case "$IFACE" in
		*#*) return 1 ;;
		*:*) return 1 ;;
		vlan*.*) return 1 ;;
		vlan*)
			IF_VLAN_ID="${IFACE#vlan}"
			[ -n "${IF_VLAN_RAW_DEVICE:-}" ] && return 0
			return 1
			;;
		*.*)
			IF_VLAN_RAW_DEVICE="${IFACE%.*}"
			IF_VLAN_ID="${IFACE##*.}"
			return 0
			;;
		*)
			[ -z "${IF_VLAN_ID:-}" ] && return 1
			[ -z "${IF_VLAN_RAW_DEVICE:-}" ] && return 1
			return 0
			;;
	esac
}

case "$PHASE" in
depend)
	# vlan-raw-device
	if is_vlan; then
		echo "$IF_VLAN_RAW_DEVICE"

	# veth-peer-name
	elif [ "${IF_LINK_TYPE}" = "veth" -a "${IF_VETH_PEER_NAME}" ]; then
		echo "${IF_VETH_PEER_NAME}"
	fi
	;;

create)
	if [ "${IF_LINK_TYPE}" = "dummy" ]; then
		if [ -d "/sys/class/net/${IFACE}" ]; then
			iface_type=$(ip -d link show dev "${IFACE}" | head -n3 | tail -n1 | awk '{ print $1 }')
			if [ "${iface_type}" != 'dummy' ]; then
				echo "Interface ${IFACE} exists but is of type ${iface_type} instead of dummy"
				exit 1
			fi

			exit 0
		fi

		${MOCK} ip link add "${IFACE}" type dummy

	elif [ "${IF_LINK_TYPE}" = "veth" ]; then
		if [ ! -d "/sys/class/net/${IFACE}" ]; then
			ARGS=""
			if [ "${IF_VETH_PEER_NAME}" ]; then
				ARGS="peer ${IF_VETH_PEER_NAME}"
			fi

			${MOCK} ip link add "${IFACE}" type veth ${ARGS}
		fi

	elif is_vlan; then
		if [ -d "/sys/class/net/${IFACE}" ]; then
			exit 0
		fi

		if [ -z "${MOCK}" ]; then
			if [ ! -d "/sys/class/net/${IF_VLAN_RAW_DEVICE}" ]; then
				echo "Underlay device ${IF_VLAN_RAW_DEVICE} for ${IFACE} does not exist"
				exit 1
			fi

			if ! [ -d /proc/net/vlan ]; then
				echo "Loading 8021q kernel module for VLAN support"
				${MOCK} modprobe 8021q
			fi
		fi

		${MOCK} ip link add link "${IF_VLAN_RAW_DEVICE}" name "${IFACE}" type vlan id "${IF_VLAN_ID}"
	fi
	;;
up)
	IF_LINK_OPTIONS="$IF_LINK_OPTIONS"
	[ -n "$IF_MTU" ] && IF_LINK_OPTIONS="$IF_LINK_OPTIONS mtu $IF_MTU"
	[ -n "$IF_HWADDRESS" ] && IF_LINK_OPTIONS="$IF_LINK_OPTIONS address $IF_HWADDRESS"

	${MOCK} ip link set up dev "${IFACE}" ${IF_LINK_OPTIONS}

	# Set alias is configured
	if [ "${IF_ALIAS}" ]; then
		${MOCK} ip link set alias "${IF_ALIAS}" dev "${IFACE}"
	fi
	;;
down)
	# Don't complain about a vanished interface when downing it
	if [ -z "${MOCK}" -a ! -d "/sys/class/net/${IFACE}" ]; then
		exit 0
	fi

	${MOCK} ip link set down dev "${IFACE}"
	;;
destroy)
	if [ "${IF_LINK_TYPE}" = "dummy" ] || [ "${IF_LINK_TYPE}" = "veth" ] || is_vlan; then
		if [ -z "${MOCK}" -a ! -d "/sys/class/net/${IFACE}" ]; then
			exit 0
		fi

		${MOCK} ip link del "${IFACE}"
	fi
	;;
esac