Revise paste ImageMagick FZF Script

#!/bin/bash
###################################################################### 
#Copyright (C) 2020  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/>.
######################################################################

dir="output"
mkdir -p "$dir"
files="$(ls *.{jpg,png,JPG,JPEG,jpeg,gif} 2>/dev/null)"
functions="grey
sepia
resize
equalize"

function main(){
  files="$(echo "$files"|fzf -m --prompt "Please Select Images: " )"
  exit-none "$files"

func="$(echo "$functions"|fzf --prompt "Select Function: " )"
  exit-none "$func"

if [ "$func" = "resize" ];then
    percent
  fi

for img in $files
  do
    ext="$(echo "$img"|cut -d\. -f2)"
    img2="$(echo "$img"|cut -d\. -f1)_$(date +%s).$ext"
    echo "Converting $img to $dir/${img2}"
    $func "$img" "$dir/${img2}"
  done
}

function percent(){
  perc="$(seq 1 200|fzf --prompt "Select a Percent")%"
}

#exit if none selected
function exit-none(){
  if [ "$1" = "" ];then
    echo "None Selected"
    exit
  fi
}

#Image Functions
function equalize(){
  convert "$1" -equalize "$2"
}

function grey(){
  convert "$1" -colorspace Gray "$2"
}

function sepia(){
  convert "$1" -sepia-tone '80%' "$2"
}

function resize(){
  convert "$1" -resize "${perc}" "$2"
}

main