Set a file's creation date as it's filename

Date As Filename.sh

#!/usr/bin/env bash
#
# Retrievs a file's  modified date and
# set's it as it's fielname.
#
 
declare -a files="${1}"
## Check if file has been specified
if [[ -z ${files} ]]; then
  echo "No file(s) specified"
  exit 1
fi
echo $files
for i in $files; do
  ## Get file info
  declare file_extension="${i##*.}"
  ## it's a hack… i know
  declare file_date=$(stat -x ${i} | grep -e "Modify" | cut -f2-5 -d " ")
  declare new_file_name="${file_date}.${file_extension}"
  new_file_name=${new_file_name// /_}
  new_file_name=${new_file_name//:/-}
 
  echo "File: ${i}"
  echo "Type: $file_extension"
  echo "Date: ${file_date}"
  echo "New Filename: ${new_file_name}"
 
  echo ""
  echo "Changing file name…"
  mv "${i}" "${new_file_name}"
  if [ "$?" != "0" ]; then
    exit 1
  fi
done
 
echo ""
echo "All done!"
exit 0