Slugify file names

slugifile

#!/bin/sh

if [ -z "$1" ]; then
  echo "slugifile <file name> [.ext]"
fi

bn=$(basename "$1" "$2")
slug=$(echo "$bn" | iconv -t ascii//TRANSLIT | sed -r s/[^a-zA-Z0-9]+/-/g | sed -r s/^-+\|-+$//g | tr A-Z a-z)
if [ -z "$2" ]; then
	echo "$slug"
else
	echo "$slug.$2" | sed 's/\.\./\./'
fi