#!/bin/sh
# This script expects a system with resolvconf (openresolv) and iproute2

[ -z "$1" ] && echo "Error: should be called from udhcpc6" && exit 1

ACTION="$1"
RESOLV_CONF="/run/resolvconf/interfaces/${interface}-ipv6.conf"
NTPFILE="/run/chrony/dhcp-sources.d/${interface}-ipv6.sources"

[ -n "$metric" ] || metric=5

if [ -z "${IF_WAIT_DELAY}" ]; then
	IF_WAIT_DELAY=10
fi

log()
{
    logger -I $$ -t udhcpc6 -p user.notice "${interface}: $*"
}

dbg()
{
    logger -I $$ -t udhcpc6 -p user.debug "${interface}: $*"
}

err()
{
    logger -I $$ -t udhcpc6 -p user.err "${interface}: $*"
}

clr_dhcpv6_addresses()
{
    addrs=$(ip -j addr show dev $interface \
		| jq -c '.[0].addr_info[] | select(.family == "inet6") | select(.protocol == "dhcp")')

    for addr in $addrs; do
	ip="$(echo "$addr" | jq -r '."local"')"
	prefix="$(echo "$addr" | jq -r '."prefixlen"')"
	log "removing $ip/$prefix"
	ip addr del "$ip/$prefix" dev "$interface"
    done
}

log "action $ACTION"
case "$ACTION" in
    deconfig)
	clr_dhcpv6_addresses

	# drop info from this interface
	rm -f "$RESOLV_CONF"
	rm -f "$NTPFILE"
	;;

    leasefail|nak)
	# DHCPv6 lease failed - log it
	err "DHCPv6 lease failed"
	;;

    renew|bound)
	# Add IPv6 address if provided (stateful DHCPv6)
	if [ -n "$ipv6" ]; then
	    if /bin/ip addr add dev $interface $ipv6 proto dhcp; then
		log "assigned address $ipv6"
	    fi
	fi

	# Handle delegated prefix (prefix delegation)
	if [ -n "$ipv6prefix" ]; then
	    log "received delegated prefix $ipv6prefix"
	    # Prefix delegation handling could be added here
	    # For now, just log it - actual routing/distribution
	    # would need additional configuration
	fi

	# drop info from this interface
	truncate -s 0 "$RESOLV_CONF"

	# DHCPv6 domain search list (option 24)
	if [ -n "$search" ]; then
	    dbg "adding search $search"
	    echo "search $search # $interface" >> $RESOLV_CONF
	fi

	# DHCPv6 DNS servers (option 23)
	if [ -n "$dns" ]; then
	    for i in $dns ; do
		dbg "adding dns $i"
		echo "nameserver $i # $interface" >> $RESOLV_CONF
	    done
	    resolvconf -u
	fi

	# NTP servers (option 56)
	if [ -n "$ntpsrv" ]; then
	    truncate -s 0 "$NTPFILE"
	    for srv in $ntpsrv; do
		dbg "got NTP server $srv"
		echo "server $srv iburst" >> "$NTPFILE"
	    done
	    chronyc reload sources >/dev/null
	fi
	;;
esac

HOOK_DIR="$0.d"
for hook in "${HOOK_DIR}/"*; do
    [ -f "${hook}" -a -x "${hook}" ] || continue
    "${hook}" "$ACTION"
done

exit 0