#!/bin/bash

# apt-cyg install ImageMagick

# done properly 2014-07-07 by mza
# 2015-01-25 updated
# 2019-10-17 updated
# 2022-08-31 updated
# 2023-04-27 updated

declare res
#res="640x480"
#res="1024x768"
#res="1280x1024"
#res="1600x1200"
#res="1632x1224"
#res="3130x2075"
res="1600x1600"
#res="1800x1800"
#res="2000x2000"
#res="2100x2100"

function run {
	local dir="${@}"
	if [ -e "${dir}" ] && [ -d "${dir}" ] && [ "${dir: -7}" != "@eaDir/" ]; then
		echo "$dir"
		cd "$dir"
		# find files and create a lowres version of each in lowres/
		find -maxdepth 1 -type f -iname "*.jpg" -o -iname "*.jpeg" -o -iname "*.png" | while read each; do
			mkdir -p "lowres"
			if [ "${each}" -nt "lowres/${each}" ]; then
				echo "converting ${each} to ${res}"
				convert "${each}" -geometry ${res} "lowres/${each}"
				touch --no-create "lowres/${each}" --reference="${each}"
			fi
		done
		# if it didn't make a lowres/ subdir, then there's no source files and we're done
		if [ ! -e "lowres" ]; then
			return
		fi
		# delete files in lowres/ that don't have a match:
		for each in "lowres"/*; do
			if [ "${each}" == "lowres/*" ]; then
				continue
			fi
			if [ -e "$each" ]; then
				local name=$(echo "$each" | sed -e "s,\(.\+\)/lowres\(/.\+\),\1\2,")
				#echo "$each $name"
				if [ ! -e "${name}" ]; then
					rm "${each}"
				fi
			fi
		done
		local -i count_of_valid_source_files=0
		for each in "lowres"/*; do
			if [ "${each}" == "lowres/*" ]; then
				continue
			fi
			count_of_valid_source_files=$((count_of_valid_source_files+1))
		done
		#echo "$count_of_valid_source_files"
		if [ ${count_of_valid_source_files} -lt 1 ]; then
			echo "removing unneeded lowres subdir..."
			rm -rf "lowres"
		fi
	fi
}

declare localdir=$(pwd)
#echo "localdir = $localdir"
# https://superuser.com/a/1070947/539022
if [ $# -gt 0 ]; then
	for each; do
		cd "${localdir}"
		run "$each"
	done
else
	find . -type d -name "lowres" -o -name "@eaDir" -prune -o -type d -exec $0 "{}" \;
	#find . -type d -name "lowres" -prune -o -type d -print
fi