#!/bin/bash

contrast=0
darkness=10
hex='d7afaf'
hex_alt='111317'
invert_flag=''
darkness_color='black'

help() {
  executable_path=$(basename "${0}")
  printf "Usage: %s {FLAGS} [FILE]\n\
  ARGUMENTS:\n\
    -h    display this help menu\n\
    -i    invert original image colors before applying color effects (off by default)\n\
    -p    [d7afaf] Primary hex color\n\
    -s    [111317] Secondary hex color\n\
    -c    [0] Contrast\n\
    -d    [10] Darkness\n\
    FILE  Full path to original image file\n" "${executable_path}"
  exit 1
}

while getopts "hb:d:c:p:s:i" flag 2>/dev/null; do
  case "${flag}" in
  h)
    help
    ;;
  d)
    darkness="${OPTARG}"
    ;;
  b)
    darkness_color='white'
    darkness="${OPTARG}"
    ;;
  c)
    contrast="${OPTARG}"
    ;;
  p)
    hex="${OPTARG//#/}"
    ;;
  s)
    hex_alt="${OPTARG//#/}"
    ;;
  i)
    invert_flag='-negate'
    ;;
  *)
    printf "[ERROR] Invalid flag: %s\n\n" "${flag}"
    help
    ;;
  esac
done

shift $((OPTIND - 1))

file="${1}"

if [[ -z ${file} || ! -f "${file}" ]]; then
  printf '[ERROR] Please provide an image file!\n\n'
  help
fi

hex="${hex//#/}"
hex_alt="${hex_alt//#/}"

printf "darkness: %s\ncontrast: %s\nprimary color: #%s\nsecondary color: #%s\nfile: %s\n" "${darkness}" "${contrast}" "${hex}" "${hex_alt}" "${file}"

new_filename=$(basename "${file}")

convert "${file}" ${invert_flag} -contrast-stretch "${contrast}"% -fill "${darkness_color}" -colorize "${darkness}"% -set colorspace Gray -separate -average +level-colors "#${hex_alt},#${hex}" "${new_filename}-recolored-$(date +%Y-%m-%d_%H-%M-%S).jpg"

#convert "${1}" -contrast-stretch 7% -set colorspace Gray -separate -average +level-colors "#111317","#d7afaf" "$(basename ${1})-recolored-$(date +%Y-%m-%d_%H-%M-%S).jpg"

#convert "${1}" -linear-stretch 90% -fill black -colorize 5% -set colorspace Gray -separate -average +level-colors "#111317","#d7afaf" "$(basename ${1})-recolored-$(date +%Y-%m-%d_%H-%M-%S).jpg"
#convert "${1}" -contrast-stretch 5% -fill black -colorize 5% -set colorspace Gray -separate -average +level-colors "#111317","#d7afaf" "$(basename ${1})-recolored-$(date +%Y-%m-%d_%H-%M-%S).jpg"

#convert "${1}" -contrast-stretch 25% -fill black -colorize 25% -set colorspace Gray -separate -average +level-colors "#111317","#d7afaf" "$(basename ${1})-recolored-$(date +%Y-%m-%d_%H-%M-%S).jpg"
#convert "${1}" -contrast-stretch 100% -fill black -colorize 25% -set colorspace Gray -separate -average +level-colors "#111317","#d7afaf" "$(basename ${1})-recolored-$(date +%Y-%m-%d_%H-%M-%S).jpg"