# Use the provided interface, otherwise the device used for the default route.
if [[ -n $BLOCK_INSTANCE ]]; then
  IF=$BLOCK_INSTANCE
else
  IF=$(ip route | awk '/^default/ { print $5 ; exit }')
fi

# As per #36 -- It is transparent: e.g. if the machine has no battery or wireless
# connection (think desktop), the corresponding block should not be displayed.
[[ ! -d /sys/class/net/${IF} ]] && exit

if [[ "$(cat /sys/class/net/$IF/operstate)" = 'down' ]]; then
  echo down # full text
  echo down # short text
  echo \#FF0000 # color
  exit
fi

case $1 in
  -4)
    AF=inet ;;
  -6)
    AF=inet6 ;;
  *)
    AF=inet6? ;;
esac

# if no interface is found, use the first device with a global scope
IPADDR=$(ip addr show $IF | perl -n -e "/$AF ([^\/]+).* scope global/ && print \$1 and exit")

case $BLOCK_BUTTON in
  3) echo -n "$IPADDR" | xclip -q -se c ;;
esac

echo "$IPADDR" # full text
echo "$IPADDR" # short text