#!/bin/sh

case $0 in
  *"timer"*)
    [ $# -ne 2 ] && printf "specify minutes and \
      seconds\n" && exit 1
    sleep $(($1 * 60 + $2))
    printf "your timer is done\a\n"
    exit 0
    ;;
  *"alarm"*)
    [ $# -ne 1 ] && printf "specify time\n" && exit 1
    ttw=$(($(date +%s --date="$1 tomorrow") - $(date +%s)))
    sleep $ttw
    printf "your alarm is done\a\n"
    exit 0
    ;;
    *"tomato"*)
    [ $# -ne 2 ] && \
      printf "specify work and rest time\n" && exit 1
  counter=0
    while true; do
      printf "start work cycle %s\a\n" $(($counter + 1))
      sleep $(($1 * 60))
      printf "start rest cycle %s\a\n" $(($counter + 1))
      sleep $(($2 * 60))
      counter=$(($counter + 1))
    done
    exit 0
    ;;
  *"stopwatch"*)
    now=$(date +%s)
    read var
    printf "%s\n" $(($(date +%s) - $now))
    exit 0
    ;;
  *"verbosewatch"*)
    min=0
    sec=0
    while true; do
      printf "%02d:%02d\r" $min $sec
      sleep 1
      sec=$(($sec + 1))
      [ $sec -eq 60 ] && min=$(($min + 1)) && sec=0
    done
    exit 0
    ;;
  *)
    printf "unknown invocation\n"
    exit 2
    ;;
esac