BASIC BASH Timer with Alarm

#!/bin/bash
######################################################################
#Copyright (C) 2018  Kris Occhipinti
#https://filmsbykris.com

#BASIC TIMER with ALARM

#This program is free software: you can redistribute it and/or modify
#it under the terms of the GNU General Public License as published by
#the Free Software Foundation, either version 3 of the License, or
#(at your option) any later version.

#This program is distributed in the hope that it will be useful,
#but WITHOUT ANY WARRANTY; without even the implied warranty of
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#GNU General Public License for more details.

#You should have received a copy of the GNU General Public License
#along with this program.  If not, see <http://www.gnu.org/licenses/>.
######################################################################

if [ $# -lt 1 ]
then
  echo "Time needed"
  echo "Useage: $0 <seconds>"
  echo "Example: $0 60"
  exit 0
fi

alarm="$HOME/.alarm.wav"
time="$1"
start=$SECONDS
s=1

function main(){
  echo "Welcome..."
  while [ $s -gt 0 ]
  do
    s="$((time - (SECONDS - start)))"
    echo -ne "\r                   \r"
    echo -ne "\r$s seconds left"
    sleep 1
  done

  echo -e "\nTimes Up"

  if [ -f "$alarm" ]
  then
    play "$alarm" 2>/dev/null
  else
    for i in `seq 1 3`
    do
      play -n -c1 synth sin %-12 sin %-9 sin %-5 sin %-2 fade h 0.1 1 0.1 2>/dev/null
    done
  fi
  exit 0
}

main