#!/bin/sh
set -euf

# wrapper script over --select-file for downloading from aria2c torrents

# escape stuff for evaluating
escape() {
	sed -e "s/^$/''/" -e "s/'/'\\\\''/g" <<-EOF
		$1
	EOF
}

errecho() { printf '%s\n' "$*" >&2; }

FILTER_CMD="" FILTER_STR="" DOWNLOAD=""
while getopts ":dFin:" OPT; do
	case "$OPT" in
		d) DOWNLOAD=1 ;;
		F|i) FILTER_STR="${FILTER_STR} -$OPTARG" ;;
		n)
			FILTER_CMD="$FILTER_CMD | grep -E ${FILTER_STR} -e '$(escape "$OPTARG")'"
			;;
		*)
	esac
done
shift $((OPTIND - 1))

[ -z "${1:-}" ] && errecho "error: torrent file needed" && exit 1
[ -z "$FILTER_CMD" ] && errecho "error: no filters! use -n" && exit 1

inds=$(eval "aria2c -S '$(escape "$1")' $FILTER_CMD | cut -d '|' -f 1 | tr -d ' ' | paste -s -d ','")

echo "$inds"

if [ -n "$DOWNLOAD" ]; then
	aria2c --select-file="$inds" "$1"
fi