#!/bin/bash

# Build instructions:
#  https://medium.com/@eplt/5-minutes-to-install-imagemagick-with-heic-support-on-ubuntu-18-04-digitalocean-fe2d09dcef1
# Command:
#  https://zwbetz.com/convert-heic-images-to-jpg/
#
# Other useful mogrify commands:
# -rotate 10 *.jpg # Rotates 10° clockwise
# -extent "1900x3100" -gravity center *.jpg # Crops to 1900x3100 based on the center of the image
# -resize "750x1550" # Shrinks (or grows) the image to the requested size

red="$(tput setaf 1)"
rst="$(tput sgr0)"

# trap ctrl-c and call ctrl_c()
# https://rimuhosting.com/knowledgebase/linux/misc/trapping-ctrl-c-in-bash
trap ctrl_c INT
function ctrl_c() {
 if [ $filecount -eq 0 ]; then printf "%s\n" "${rst}${red}exiting${rst}"
 else printf "\n%s\n%s\n\n" "${rst}${red}CTRL+C detected - this may have corrupted the most recent attempted file" "conversion. Please inspect the latest file and delete or retry as needed.${rst}"
 fi
 exit
}

padding="  "

if [[ "${@}" == *"-h"* ]]; then
 printf "%s\n" "Command:"
 printf "$padding%s\n" "Converts heic files (Apple's native picture format) to either jpg (default)"
 printf "$padding%s\n" "or png (larger file size) for easier manipulation or sharing. Requires that"
 printf "$padding%s\n" "Imagemagick's mogrify tool be complied and installed with heic support. See"
 printf "$padding%s\n" "step 1 at https://dismy.link/heicmogrify for a brief install guide."
 printf "%s\n" "Command usage:"
 printf "$padding%-20s%s\n" "--dir [directory]" "Specify a directory other than current"
 printf "$padding%-20s%s\n" "-d --delete" "Delete original files (default keeps originals)"
 printf "$padding%-20s%s\n" "-q --quiet" "Suppresses progress output (summaries are still displayed)"
 printf "$padding%-20s%s\n" "[--png|--jpg]" "Save as jpg/png (default is jpg)"
 printf "$padding%-20s%s\n" "-h --help" "Print this help message and exit"
 exit 0
fi

# DEFAULTS
# The folder with the files you want to convert
directory="`pwd`"
# Set to 0 to delete the original .heic files after they are converted
keeporiginals=1
# Set to 0 for PNG (much larger file size)
saveasjpg=1
# Suppress progress output
keepquiet=0

filecount=0
customdir=0
instant=0
for _arg in ${@}; do
 if [ $customdir -eq 1 ]; then directory="$_arg"; customdir=2; continue; fi
 if [ "$_arg" == "--dir" ]; then customdir=1; continue; fi
 if [ "$_arg" == "-d" ]; then keeporiginals=0; continue; fi
 if [ "$_arg" == "--delete" ]; then keeporiginals=0; continue; fi
 if [ "$_arg" == "-q" ]; then keepquiet=1; continue; fi
 if [ "$_arg" == "--quiet" ]; then keepquiet=1; continue; fi
 if [ "$_arg" == "--png" ]; then saveasjpg=0; continue; fi
 if [ "$_arg" == "--jpg" ]; then saveasjpg=1; continue; fi
 if [ "$_arg" == "-now" ]; then instant=1; continue; fi
 if [ "$_arg" == "--now" ]; then instant=1; continue; fi
done

# Make sure the mogrify command is available. If this is being
#  run as a cron job the which command will fail so we check the
#  default location just in case.
mymogrify=`which mogrify`
which mogrify > /dev/null
if [[ $? -eq 1 ]]; then
 if [[ -e "/usr/local/bin/mogrify" ]]; then
  mymogrify="/usr/local/bin/mogrify"
 else
  printf "%s\n" "Unable to locate the mogrify command. Please follow the build and"
  printf "%s\n" "installation guide at https://dismy.link/heicmogrify to install"
  printf "%s\n" "the ImageMagick mogfify tool on your system with heic support."
  exit 1
 fi
fi

# summary:
printf "\n%s\n" "Summary:"
printf "$padding%s\n" "Binary:    $mymogrify"
printf "$padding%s\n" "Directory: $directory"
[ $keeporiginals -eq 0 ] && printf "$padding%s\n" "Originals: Delete" || printf "$padding%s\n" "Originals: Keep"
[ $keepquiet -eq 0 ] && printf "$padding%s\n" "Output:    Visible" || printf "$padding%s\n" "Output:    Hidden"
[ $saveasjpg -eq 0 ] && printf "$padding%s\n" "Save as:   PNG" || printf "$padding%s\n" "Save as:   JPG"
if [ $instant -eq 0 ]; then
 printf "\n%s" "Press enter to begin or ^c to exit"
 read
fi

[ $saveasjpg -eq 0 ] && destformat="png" || destformat="jpg"
# Loop over all the .heic files in the folder
for heic in *.heic; do
 # Drop the .heic extension and append .jpg instead
 img=`echo "$heic" | rev | cut -d. -f2- | rev`.$destformat
 if [ -f "$img" ]; then [ $keepquiet -eq 0 ] && printf "%s\n" "Skipping $heic ($img exists)"
 else [ $keepquiet -eq 0 ] && printf "%s\n" "Converting $heic to $img"; fi
 [ -f "$img" ] || let filecount=filecount+1
 # If the file we are going to make does not exist, run the command to convert it
 if [ ! -f "$img" ]; then
  $mymogrify -format $destformat "$heic"
  mogrified=$?
  if [ $mogrified -ne 0 ]; then
   printf "\n%s\n\n" "${rst}${red}Encountered the above error while trying to mogrify. Exiting.${rst}"
   exit $mogrified
  fi
 fi
 # If we don't want the originals, give them the axe
 [ $keeporiginals -eq 0 ] && rm "$heic"
done

if [ $filecount -gt 0 ]; then
 if [ $filecount -eq 1 ]; then
  printf "\n%s\n\n" "Script complete. Converted $filecount heic file to $destformat"
 else
  printf "\n%s\n\n" "Script complete. Converted $filecount heic files to $destformat"
 fi
else
 if [ $customdir -eq 2 ]; then
  printf "\n%s\n\n" "Found 0 heic files to convert. Are you sure you specified the right directory?"
 else
  printf "\n%s\n\n" "Found 0 heic files to convert. Are you sure you're in the right directory?"
 fi
fi