#!/bin/bash
#   pacdiff : a simple pacnew/pacorig/pacsave updater
#
#   Copyright (c) 2007 Aaron Griffin <aaronmgriffin@gmail.com>
#
#   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 2 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/>.
#

diffprog=${DIFFPROG:-vimdiff}
diffsearchpath=${DIFFSEARCHPATH:-/etc}
locate=0

usage() {
	echo "pacdiff : a simple pacnew/pacorig/pacsave updater"
	echo "Usage : pacdiff [-l]"
	echo "  -l/--locate makes pacdiff use locate rather than find"
	echo "  DIFFPROG variable allows to override the default vimdiff"
	echo "  DIFFSEARCHPATH allows to override the default /etc path"
	echo "Example : DIFFPROG=meld DIFFSEARCHPATH=\"/boot /etc /usr\" pacdiff"
}

cmd() {
	if [ $locate -eq 1 ]; then
		locate -0 -e -b \*.pacnew \*.pacorig \*.pacsave
	else
		find $diffsearchpath \( -name \*.pacnew -o -name \*.pacorig -o -name \*.pacsave \) -print0
	fi
}

if [ $# -gt 0 ]; then
	case $1 in
		-l|--locate)
		locate=1;;
		*)
		usage; exit 0;;
	esac
fi

# see http://mywiki.wooledge.org/BashFAQ/020
while IFS= read -u 3 -r -d '' pacfile; do
	file="${pacfile%.pac*}"
	echo "File: $file"
	if [ ! -f "$file" ]; then
		echo "  $file does not exist"
		rm -i "$pacfile"
		continue
	fi
	check="$(cmp "$pacfile" "$file")"
	if [ -z "${check}" ]; then
		echo "  Files are identical, removing..."
		rm "$pacfile"
	else
		echo -n "  File differences found. (V)iew, (S)kip, (R)emove: [v/s/r] "
		while read c; do
			case $c in
				r|R) rm "$pacfile"; break ;;
				v|V)
				$diffprog "$pacfile" "$file"
				rm -i "$pacfile"; break ;;
				s|S) break ;;
				*) echo -n "  Invalid answer. Try again: [v/s/r] "; continue ;;
			esac
		done
	fi
done 3< <(cmd)

exit 0

# vim: set ts=2 sw=2 noet:
