#!/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=59
        sec=55
        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