#!/bin/bash
#   Copyright (c) 2013 by Luke Shumaker <lukeshu@sbcglobal.net>
#
#   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; either version 3 of the License, or
#   (at your option) any later version.
#
#   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/>.

default_libdir=/usr/lib/libretools

print() {
	fmt=$1; shift
	printf -- "$fmt\n" "$@"
}

cmd=${0##*/}
usage() {
	. libremessages
	print 'Usage: . $(%s LIBRARY)' "$cmd"
	print "Finds a shell library file"
	echo
	print "While some libraries can be sourced just by their name because"
	print "they are installed in PATH (like libremessages), some are not"
	print "installed there (like conf.sh), so a path must be given."
	print "Hardcoding that path is the way of the dark side."
	echo
	print "By default, it looks for the files in '%s'," "$default_libdir"
	print "but this can be changed with the environmental variable"
	print "LIBRETOOLS_LIBDIR."
	echo
	print "Example usage:"
	print '  . $(librelib conf.sh)'
}

main() {
	if [[ $# != 1 ]]; then
		usage >&2
		return 2
	fi
	if [[ $1 == '-h' ]]; then
		usage
		return 0;
	fi

	if [[ -z $LIBRETOOLS_LIBDIR ]]; then
		export LIBRETOOLS_LIBDIR=$default_libdir
	fi

	lib=$1
	lib=${lib#libre}
	lib=${lib%.sh}

	for file in ${lib} libre${lib} ${lib}.sh libre${lib}.sh; do
		if [[ -f "$LIBRETOOLS_LIBDIR/$file" ]]; then
			printf '%s\n' "$LIBRETOOLS_LIBDIR/$file"
			return 0;
		fi
	done
	printf 'librelib: could not find library `%s`\n' "$lib" >> /dev/stderr
	return 1
}

main "$@"