#!/bin/bash

# Relational pipes
# Copyright © 2019 František Kučera (Frantovo.cz, GlobalCode.info)
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, version 3 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.


# Quite dirty hack to get some information about given PDF file
# TODO: better field names, more stable API
# TODO: call a PDF library rather than parse output of a commandline tool with human readable output

if [[ $# == 0 ]]; then
	echo "1";
	if [[ "x$field" == "xPages" ]]; then echo "integer";
	elif [[ -z "${field+x}" ]]; then echo "boolean";
	else echo "string";
	fi
elif [[ -f "$1" || -d "$1" ]]; then
	info="`pdfinfo -isodates "$1"`";
	valid=$?;
	if [[ "x$field" == "xPages" ]]; then
		if [[ $valid == 0 ]]; then
			echo "$info" | grep "^$field:" | sed -E 's/[^:]+:\s+(.*)/\1/g' | tr -d '\n';
		else
			printf 0;
			# exit 40; # TODO: null
		fi
	elif [[ -z "${field+x}" ]]; then
		if [[ $valid == 0 ]]; then printf "true"; else printf "false"; fi
	else
		echo "$info" | grep "^$field:" | sed -E 's/[^:]+:\s+(.*)/\1/g' | tr -d '\n';
	fi
else
	exit 40;
fi