#!/bin/bash

# Converts all files in current directory
# ending with *.NEF to JPEGs (.jpg) using darktable-cli
# Based on:
# https://askubuntu.com/a/1337782

set -eo pipefail

err() {
  ( 1>&2 echo -e "[Error]\n$1\nExiting" )
  exit 1
}

main() {
  command -v "darktable-cli" &>/dev/null || err "Expected command darktable-cli to be available"

  local nefs=()
  mapfile -t nefs < <(find_nefs)

  local i=
  local nef=
  local jpgname=
  for (( i = 0; i < ${#nefs[@]}; i++ )); do
    nef="${nefs[i]}"
    jpgname="$( basename -s ".NEF" "$nef" ).jpg"

    echo "$i: ${nef} -> ${jpgname}"

    [ -f "$jpgname" ] && err "JPEG file named \"${jpgname}\" already exists"

    darktable-cli "$nef" "$jpgname"
  done

  echo "Done"
}

find_nefs() {
  find . -type f -iname '*.nef'
}

main "$@"