Rename downloaded manga file to well-organize name

rename.sh

#!/bin/bash
# Filename: rename.sh

path=$1
extension=$2
count=1
replace=""
for entry in "$path"/*
do  
  oldfile=$(echo ${entry/$path/$replace}| cut -d'/' -f 2)
  newfile="$count$extension"
  mv "$path/$oldfile" "$path/$newfile"
  let count++
done