#!/bin/sh
# Syncpkgs - fetch updated packages from repository

# Repository URL with Slackware packages
MIRROR="http://<some.slackware.mirror>/slackware-12.0/patches"

# Directory where packages are stored
PACKAGES_CACHE=${PACKAGES_CACHE:-~/var/cache/slackware}
[ -d ${PACKAGES_CACHE} ] || mkdir -p ${PACKAGES_CACHE}

# Wheter to check gpg-signatures of packages
VERIFY_SIG="y"

# Create list of localy installed packages
FLIST_LOCAL=$(ls -1 /var/log/packages/)

# Create list of available packages in repository
wget -O ${PACKAGES_CACHE}/FILE_LIST ${MIRROR}/FILE_LIST || { echo "Error at fetching filelist !" >&2; exit 1; }
FLIST_REMOTE=$(sed -n 's/.*\s\.\/\([^\/]*\/.*\)\.tgz$/\1/p' ${PACKAGES_CACHE}/FILE_LIST)

# Fetch packages not yet in the local cache
for pkg in $FLIST_REMOTE;do
	pkg_name=$(basename $pkg)
	pkg_subdir=$(dirname $pkg)
	pkgname_re='(^|\s)(('$(expr $pkg_name : '\(.*\)-.*-.*-.*$')')-[^-]*-[^-]*-[^-]*)(\s|$)'
	if [[ ${FLIST_LOCAL} =~ ${pkgname_re} ]]; then
		if [[ ! ${EXCLUDE} =~ ${BASH_REMATCH[3]} ]]; then
			if [ ! -r ${PACKAGES_CACHE}/${pkg}.tgz ]; then
				[ -d ${PACKAGES_CACHE}/${pkg_subdir} ] ||
					mkdir -p ${PACKAGES_CACHE}/${pkg_subdir}
				wget -c -O ${PACKAGES_CACHE}/$pkg.tgz $MIRROR/$pkg.tgz
				[ $? -ne 0 ] &&
					{ echo "Failed to download $pkg.tgz !" >&2; \
					rm -f ${PACKAGES_CACHE}/$pkg.tgz; exit 1; }
			fi
			if [ ! -r ${PACKAGES_CACHE}/${pkg}.tgz.asc ]; then
				wget -O ${PACKAGES_CACHE}/$pkg.tgz.asc $MIRROR/$pkg.tgz.asc
				[ $? -ne 0 ] &&
					{ echo "Failed to download $pkg.tgz.asc !" >&2; \
					rm -f ${PACKAGES_CACHE}/$pkg.tgz.asc; exit 1; }
				[ $VERIFY_SIG == "y" ] &&
					gpg --verify ${PACKAGES_CACHE}/$pkg.tgz.asc &> /dev/null
				[ $? -ne 0 ] &&
					{ echo "Wrong signature for $pkg.tgz !" >&2; \
					rm -f ${PACKAGES_CACHE}/$pkg.tgz*; \
					exit 1; }
			fi
		fi
	fi
done
                          
# Remove all outdated packages - not available in repository
for pkgfile in $(find ${PACKAGES_CACHE} -type f -name '*.tgz'); do
	if [[ ! ${FLIST_REMOTE} =~ $(basename $pkgfile .tgz) ]]; then
		rm -f ${pkgfile}
		rm -f ${pkgfile}.asc
	fi
done