renamin.sh

#!/bin/bash
COLOR_DEFAULT='\033[0m'
COLOR_SUCCESS='\033[0;32m'
COLOR_WARNING='\033[1;33m'
COLOR_ERROR='\033[0;31m'
ZERO_VALUES=($(seq 1 1 9)) # Array with values from 1 to 9

# Include "0" value prefix in the first ten values 01, 02, ...
getPrefix () {
  if [[ "${ZERO_VALUES[@]}" =~ "${1}" ]]; then
    prefix="0"
  else
    prefix=""
  fi
}

renameFile () {
  getPrefix $2
  nameUpdated="$(date -r "$1" +"%Y%m%d%H%M%S")$prefix$2.jpg"

  if [[ $1 == $nameUpdated ]]; then
    printf "\nfile ${COLOR_WARNING}$1${COLOR_DEFAULT} <------> ${COLOR_WARNING}$nameUpdated${COLOR_DEFAULT}\n"
    return
  fi

  printf "\nfile ${COLOR_ERROR}$1${COLOR_DEFAULT} -------> ${COLOR_SUCCESS}$nameUpdated${COLOR_DEFAULT}\n"
  output=$(mv -v -n "$1" "$nameUpdated")
  echo $output

  # Increase counter in the new filename when cannot overwritte because duplicate dates
  echo "${output}" | grep -q "not overwritten"
  if [ $? -eq 0 ]; then
    counter=$(($2+1))
    renameFile "$1" $counter
  fi;
}

# @todo: Check if there are images in the folder
# if [[ ! -e *.{jpg, jpeg, JPG, JPEG} ]]; then  # bad !!
#   printf "\n${COLOR_ERROR}error: directory without images${COLOR_DEFAULT}\n"
#   exit
# fi

for filename in *.{jpg,jpeg,JPG,JPEG}; do
  if [ -s "$filename" ]; then
    renameFile "$filename" 1
  fi
done

exit