#!/bin/sh

usage() {
	printf "Usage: %s -s SRC -o OUTPUT -b BASE_URL\n" "$0"
}

on_interrupt() {
	print "Process aborted!\n"

	exit 130
}

main() {
	while getopts "hs:b:o:" option; do
		case "${option}" in
			h) usage; exit 0;;
			s) SRC="$OPTARG";;
			o) OUTPUT="$OPTARG";;
			b) BASE_URL="$OPTARG";;
			*) usage; exit 1;;
		esac
	done

	if [ -z "$SRC" ]; then
		printf "You must provided the source (directory).\n"
		usage
		exit 1
	fi

	if [ -z "$OUTPUT" ]; then
		printf "You must provided the output (json file).\n"
		usage
		exit 1
	fi

	if [ -z "$BASE_URL" ]; then
		printf "You must provided the base url.\n"
		usage
		exit 1
	fi

	images=""

	for image in "$SRC/"*; do
		filename="$(basename "$image")"
		date="$(printf "%s" "$filename" | sed 's#^\([[:digit:]]\{4\}\)\([[:digit:]]\{2\}\)\([[:digit:]]\{2\}\)_.*$#\3/\2/\1#')"
		images="$(
			printf '%s%s{"file":"%s/%s","date":"%s"}' \
			"$images" \
			"$(test -n "$images" && printf ",")" \
			"$BASE_URL" \
			"$filename" \
			"$date"
		)"
	done

	printf '{"images":[%s]}' "$images" > "$OUTPUT"

	exit 0
}

trap on_interrupt INT

main "$@"