#!/bin/sh
. /etc/utils.sh

log()
{
  echo "$@" >&2
}

usage()
{
  log "Usage: $0 <dev> [ip1/mask1] [ip2/mask2] ..."
  log "  dev = the interface, like eth0 or wlan1"
  log "  ip# = w.x.y.z"
  log "  mask# = CIDR mask length, like '24'"
  exit 1
}

ip_to_json()
{
  local ip mask part_ip part_mask

  # Split ip/mask into ip and mask.
  IFS='/' read part_ip part_mask <<EOF
$1
EOF
  if [ -z "$part_ip" -o -z "$part_mask" ]; then
    exit 1
  fi
  json="{ "
  if [ -n "$part_ip" ]; then
    json="$json \"new_ip_address\": \"$part_ip\""
    json="$json, \"new_subnet_mask\": \"$part_mask\""
  fi
  json="$json }"

  echo "$json"
}

if [ $# -lt 1 ]; then
  usage
fi

dev="$1"; shift

ips_json=
while [ $# -ge 1 ]; do
  if [ -n "$ips_json" ]; then
    ips_json="$ips_json,"
  fi
  ips=$(ip_to_json "$1")
  if [ $? -ne 0 ]; then
    usage
  fi
  ips_json="$ips_json $ips"
  shift
done

if [ -n "$ips_json" ]; then
  atomic /config/ip/static/$dev "$(
    echo "{ \"${dev}\": {"
    echo "  \"ip\": [ $ips_json ]"
    echo "} }"
  )"
else
  rm -f "/config/ip/static/$dev"
fi

ipapply "$dev"