#!/bin/sh
#
#    manifest - import/export a list of packages
#    Copyright (C) 2016 Dustin Kirkland
#
#    Authors: Dustin Kirkland <kirkland@byobu.org>
#
#    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/>.

set -e

if ! command -v pastebinit >/dev/null 2>&1; then
	echo "ERROR: pastebinit not found.  Hint:" 1>&2
	echo "  sudo apt install pastebinit" 1>&2
	exit 1
fi

export_packages() {
	if [ "$OBJECT" = "-" ]; then
		dpkg -l
	elif echo "$OBJECT" | grep -qs ".*://.*"; then
		dpkg -l | gzip -9 | base64 | pastebinit -b "${OBJECT##*/}"
	else
		dpkg -l > "$OBJECT"
	fi
}

import_packages() {
	if [ "$OBJECT" = "-" ]; then
		sudo apt install $(cat /dev/stdin | grep "^ii\s" | col2)
	elif echo "$OBJECT" | grep -qs ".*://.*"; then
		sudo apt install $(wget -q -O- "$OBJECT" | grep -A 999999999 '<div class="paste"><pre>' | grep -B 999999999 "^</pre>" | sed -e "s/.*<pre>//" -e "s/^<\/pre>.*//" | base64 -d | gunzip | grep "^ii\s" | col2)
	else
		sudo apt install $(cat "$OBJECT" | grep "^ii\s" | col2)
	fi
}

usage() {
	cat <<EOF
USAGE:
  $0 export [-|URL|FILENAME]
  $0 import -|URL|FILENAME
EOF
	exit 0
}

if [ -n "$1" ]; then
	ACTION="$1"
	shift
else
	usage
fi
if [ -n "$1" ]; then
	OBJECT="$1"
	shift
fi
if [ "$ACTION" = "import" ]; then
	import_packages
elif [ "$ACTION" = "export" ]; then
	[ -n "$OBJECT" ] || OBJECT="http://paste.ubuntu.com"
	export_packages
else
	usage
fi