timer

#!/bin/bash

TIME=0
while [ -n "$1" ]; do
    ARG="$1"
    COUNT=$(echo "$ARG" | grep -o '[0-9]\+')
    
    case "$ARG" in
        *s) TIME=$((TIME+COUNT));;
        *m) TIME=$((TIME+60*COUNT));;
        *h) TIME=$((TIME+60*60*COUNT));;
        *d) echo "I recommend a cronjob."; exit 1;;
        *) break;
    esac

    shift
done

if [ 0 -eq "$TIME" ]; then
    echo "I'm sure you didn't mean to set a timer zero seconds from now." >&2
    exit 1
fi

FINISH_SECONDS=$(($(date +%s)+TIME))
FINISH_TIME=$(date --date=@$FINISH_SECONDS)

MESSAGE="Timer $$ done."
DONE_CMD=( feedback -u critical "$MESSAGE" )
case "$1" in
    -r) shift; DONE_CMD=( raction poke "$@" );;
    -c) shift; DONE_CMD=( "$@" );;
    '') ;; # so we don't make MESSAGE empty with no args
    *) MESSAGE="$*";;
esac

( (
    (sleep $TIME; exit 1) &
    TIMERPID=$!
    trap "echo $TIMERPID $(($FINISH_SECONDS - $(date +%s))) $FINISH_TIME >> /tmp/timers.state" SIGUSR1
    echo "Timer set for $TIME seconds from now ($FINISH_TIME). PID=$TIMERPID";
    wait $TIMEPID && "${DONE_CMD[@]}";
    echo "Timer $TIMERPID done." >&2
)& )&