wimi

#!/bin/bash -
# Print "what is my IP address?" every 60 seconds (default) to standard output

AUTHOR="Bernard Lim"
PROG=$(basename $0)

urls=( \
"icanhazip.com" \
"my.ip.fi" \
"api.wipmania.com" \
"wtfismyip.com/text" \
"ipecho.net/plain" \
#"ifconfig.co/ip" \
"ifconfig.io/ip" \
"ifconfig.sexy/ip" \
"4.ifcfg.me/ip" \
)

# dependency message
depends() {
  echo "$PROG: depends on \`$*'" >&2
  echo "Install \`$*' and try again." >&2
  exit 1
}

# die a graceful death!
die() {
  echo "$PROG: $*" >&2
  exit 1
}

# shorter usage
short() {
  usage | sed '2q'
  echo "Try \`$PROG -h' for more information."
}

# usage
usage() {
cat <<EOF
Usage: $PROG N
Print "what is my IP address?" for every N second(s). Default N is 60s.
EOF
}

goodbye() {
  echo -e "  Goodbye!" >&2
  exit 0
}
trap goodbye INT

wip() {
  if which curl &>/dev/null; then
    while true; do
      url=${urls[$RANDOM % ${#urls[@]}]}
      ip=$(curl -m5 -s $url)
      if [ $? -eq 0 ]; then
        printf "%-20s" "${url%/*}" >&2
        printf "%s\n" $(tr -cd '[0-9].' <<<"$ip")
        break
      fi
    done
  else
    depends "curl"
  fi
}

# parse short options
OPTIND=1
while getopts ":h" opt; do
  case $opt in
    h)
      if [[ $# -ne 1 || $OPTIND -eq 1 ]]; then short; exit 1; fi
      usage
      exit 0
      ;;
   \?) die "invalid option -- '$OPTARG'";;
  esac
done
shift $((OPTIND-1))

# main
refresh=${1:-60}
if grep -Ev '^[0-9]+$' <<<"$refresh" >/dev/null; then
  die "invalid refresh rate"
fi

if [ $refresh -eq 0 ]; then
  while true; do
    read -p "Warning: refresh rate is 0s. Do you want to continue [Y/n]? " yn
    case $yn in
      [Yy]*) break;;
      [Nn]*) exit 1;;
          *) echo -e "Please answer [Y]es or [n]o\n";;
    esac
  done
fi

printf "\nRefresh \`$PROG' every %ss. Ctrl-C to quit\n\n" "$refresh"

printf "%6s  %-20s%-15s\n" "No." "Reference" "IP Address"
printf "%6s  %-20s%-15s\n" "---" "---------" "----------"

while true; do
  wip && sleep $refresh
done 2>&1 | cat -n