Notes and Reminders BASH script

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

#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/>.
######################################################################

notes="$HOME/.notes"
minutes=15 #number of minutes for notifications
url='http://filmsbykris.com/scripts/2018/note/'

function main(){
  echo "Welcome..."
  if [ "$1" = "add" ]
  then
    add
  elif [ "$1" = "notify" ]
  then
    notify
  else
    cat "$notes"
  fi

  exit 0
}

function notify(){
  c=$(date +%s)
  m=$(($minutes*60+$c))

  cat "$notes"|while read line;
  do
    time="$(echo $line|cut -d\| -f1)"
    date="$(echo $line|cut -d\| -f2)"
    title="$(echo $line|cut -d\| -f3)"
    note="$(echo $line|cut -d\| -f4)"

    if (( $time > $c ))
    then
      if (( $time < $m ))
      then
        title="$(rawurlencode "$title")"
        note="$(rawurlencode "$note")"
        url="$url?title=$title&note=$note"
        notify-send -t 0 "$title" "$note $url"
      fi
    fi
  done
}

function add(){
  echo "When would you like to be reminded?"
  read t

  date -d "$t" || (echo "bad date";exit 1)
  time="$(date +%s -d "$t")"
  date="$(date -d "$t")"
  #echo "Setting reminder for $date"

  echo -n "Title:"
  read title

  echo -n "Note:"
  read note

  echo "$time|$date|$title|$note" >> "$notes"
}


rawurlencode() {
  local string="${1}"
  local strlen=${#string}
  local encoded=""
  local pos c o

  for (( pos=0 ; pos<strlen ; pos++ )); do
     c=${string:$pos:1}
     case "$c" in
        [-_.~a-zA-Z0-9] ) o="${c}" ;;
        * )               printf -v o '%%%02x' "'$c"
     esac
     encoded+="${o}"
  done
  echo "${encoded}"    # You can either set a return variable (FASTER)
  REPLY="${encoded}"   #+or echo the result (EASIER)... or both... :p
}

main $*