#!/bin/bash
#
#   pacscripts : tries to print out the {pre,post}_{install,remove,upgrade}
#   scripts of a given package
#
#   Copyright (c) 2009 Giulio "giulivo" Fidente <giulivo.navigante@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/>.
#

progname=$(basename $0)
progver="0.4"

conf="/etc/pacman.conf"

if [ ! -r "$conf" ]; then
	echo "ERROR: unable to read $conf"
	exit 1
fi

eval $(awk '/DBPath/ {print $1$2$3}' "$conf")
eval $(awk '/CacheDir/ {print $1$2$3}' "$conf")
pac_db="${DBPath:-/var/lib/pacman}/local"
pac_cache="${CacheDir:-/var/cache/pacman/pkg}"

usage() {
	echo "This program prints out the {pre,post}_{install,remove,upgrade} scripts"
	echo "of a given package, even if it's not installed yet, without installing it!"
	echo "Usage: $progname pkgname"
	echo
	echo " OPTIONS:"
	echo "  -h, --help                 Print this help message"
	echo "  -v, --version              Print program name and version"
	echo
	echo "Example: $progname gconf-editor"
}

print_scriptlet() {
	if pacman -Q "$1" &>/dev/null; then
		pkg=$(pacman -Q "$1")
		pkg=${pkg/ /-}
		if [ -f $pac_db/$pkg*/install ]; then
			cat $pac_db/$pkg*/install
			echo
			return 0
		else
			echo "Package $1 does not include any .INSTALL script"
			return 1
		fi
	fi
	if ! pacman -Si $1 &>/dev/null; then
		echo "Package $1 not found"
		return 1
	fi
	if ! sudo pacman -Sdw --noconfirm $1 > /dev/null; then
		echo "Failed to download $1"
		return 1
	fi
	url=$(sudo pacman -Sdp $1 || tail -n1)
	filename=$(basename $url)
	if ! tar -xOf $pac_cache/$filename .INSTALL 2> /dev/null; then
		echo "Package $1 does not include any .INSTALL script"
		return 1
	fi
	echo
	return 0
}

if [ $# -ne 1 ] ; then
    usage
    exit 1
fi

case "$1" in
	--help|-h) usage; exit 0 ;;
	--version|-v) echo "$progname version $progver"; exit 0 ;;
    	*) print_scriptlet $1 ;;
esac