#!/bin/bash
#
#   repo-add - add a package to a given repo database file
#   repo-remove - remove a package entry from a given repo database file
#   @configure_input@
#
#   Copyright (c) 2006-2011 Pacman Development Team <pacman-dev@archlinux.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; 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/>.

shopt -s extglob

# gettext initialization
export TEXTDOMAIN='pacman-scripts'
export TEXTDOMAINDIR='@localedir@'

myver='@PACKAGE_VERSION@'
confdir='@sysconfdir@'

QUIET=0
DELTA=0
WITHFILES=0
SIGN=0
VERIFY=0
REPO_DB_FILE=
LOCKFILE=
CLEAN_LOCK=0

# ensure we have a sane umask set
umask 0022

m4_include(library/output_format.sh)

# print usage instructions
usage() {
	cmd=${0##*/}
	printf "%s (pacman) %s\n\n" "$cmd" "$myver"
	if [[ $cmd == "repo-add" ]] ; then
		printf "$(gettext "Usage: repo-add [options] <path-to-db> <package|delta> ...\n")"
		printf "\n"
		printf "$(gettext "\
repo-add will update a package database by reading a package file.\n\
Multiple packages to add can be specified on the command line.\n")"
		printf "\n"
		printf "$(gettext "Options:\n")"
		printf "$(gettext "  -d, --delta       generate and add delta for package update\n")"
		printf "$(gettext "  -f, --files       update database's file list\n")"
	elif [[ $cmd == "repo-remove" ]] ; then
		printf "$(gettext "Usage: repo-remove [options] <path-to-db> <packagename|delta> ...\n")"
		printf "\n"
		printf "$(gettext "\
repo-remove will update a package database by removing the package name\n\
specified on the command line from the given repo database. Multiple\n\
packages to remove can be specified on the command line.\n")"
		printf "\n"
		printf "$(gettext "Options:\n")"
	else
		printf "$(gettext "Please move along, there is nothing to see here.\n")"
		return
	fi
	printf "$(gettext "  -q, --quiet       minimize output\n")"
	printf "$(gettext "  -s, --sign        sign database with GnuPG after update\n")"
	printf "$(gettext "  -k, --key <key>   use the specified key to sign the database\n")"
	printf "$(gettext "  -v, --verify      verify database's signature before update\n")"
	printf "$(gettext "\n\
See %s(8) for more details and descriptions of the available options.\n")" $cmd
	printf "\n"
	if [[ $cmd == "repo-add" ]] ; then
		printf "$(gettext "Example:  repo-add /path/to/repo.db.tar.gz pacman-3.0.0-1-i686.pkg.tar.gz\n")"
	elif [[ $cmd == "repo-remove" ]] ; then
		printf "$(gettext "Example:  repo-remove /path/to/repo.db.tar.gz kernel26\n")"
	fi
}

version() {
	cmd=${0##*/}
	printf "%s (pacman) %s\n\n" "$cmd" "$myver"
	printf "$(gettext "\
Copyright (c) 2006-2011 Pacman Development Team <pacman-dev@archlinux.org>\n\n\
This is free software; see the source for copying conditions.\n\
There is NO WARRANTY, to the extent permitted by law.\n")"
}

# format a metadata entry
#		arg1 - Entry name
#		...  - value(s)
format_entry() {
	local field=$1; shift

	if [[ $1 ]]; then
		printf '%%%s%%\n' "$field"
		printf '%s\n' "$@"
		printf '\n'
	fi
}

find_pkgentry() {
	local pkgname=$1
	local pkgentry
	for pkgentry in $tmpdir/tree/$pkgname*; do
		name=${pkgentry##*/}
		if [[ ${name%-*-*} = $pkgname ]]; then
			echo $pkgentry
			return 0
		fi
	done
	return 1
}

# Get the package name from the delta filename
get_delta_pkgname() {
	local tmp

	tmp=${1##*/}
	echo ${tmp%-*-*_to*}
}

# write a delta entry
#   arg1 - path to delta file
db_write_delta() {
	deltafile="$1"
	pkgname="$(get_delta_pkgname $deltafile)"

	pkgentry=$(find_pkgentry $pkgname)
	if [[ -z $pkgentry ]]; then
		error "$(gettext "No database entry for package '%s'.")" "$pkgname"
		return 1
	fi
	deltas="$pkgentry/deltas"
	if [[ ! -f $deltas ]]; then
		echo -e "%DELTAS%" >$deltas
	fi
	# get md5sum and compressed size of package
	md5sum="$(openssl dgst -md5 "$deltafile")"
	md5sum="${md5sum##* }"
	csize=$(@SIZECMD@ "$deltafile")

	oldfile=$(xdelta3 printhdr $deltafile | grep "XDELTA filename (source)" | sed 's/.*: *//')
	newfile=$(xdelta3 printhdr $deltafile | grep "XDELTA filename (output)" | sed 's/.*: *//')

	if grep -q "$oldfile.*$newfile" $deltas; then
		sed -i.backup "/$oldfile.*$newfile/d" $deltas && rm -f $deltas.backup
	fi
	msg2 "$(gettext "Adding 'deltas' entry : %s -> %s")" "$oldfile" "$newfile"
	echo ${deltafile##*/} $md5sum $csize $oldfile $newfile >> $deltas

	return 0
} # end db_write_delta

# remove a delta entry
#   arg1 - path to delta file
db_remove_delta() {
	deltafile="$1"
	filename=${deltafile##*/}
	pkgname="$(get_delta_pkgname $deltafile)"

	pkgentry=$(find_pkgentry $pkgname)
	if [[ -z $pkgentry ]]; then
		return 1
	fi
	deltas="$pkgentry/deltas"
	if [[ ! -f $deltas ]]; then
		return 1
	fi
	if grep -q "$filename" $deltas; then
		sed -i.backup "/$filename/d" $deltas && rm -f $deltas.backup
		msg2 "$(gettext "Removing existing entry '%s'...")" "$filename"
		return 0
	fi

	return 1
} # end db_remove_delta

check_gpg() {
	if ! type -p gpg >/dev/null; then
		error "$(gettext "Cannot find the gpg binary! Is GnuPG installed?")"
		exit 1 # $E_MISSING_PROGRAM
	fi
}

# sign the package database once repackaged
create_signature() {
	(( ! SIGN )) && return
	local dbfile="$1"
	local ret=0
	msg "$(gettext "Signing database...")"

	local SIGNWITHKEY=""
	if [[ -n $GPGKEY ]]; then
		SIGNWITHKEY="-u ${GPGKEY}"
	fi
	gpg --detach-sign --use-agent ${SIGNWITHKEY} "$dbfile" &>/dev/null || ret=$?

	if (( ! ret )); then
		msg2 "$(gettext "Created signature file %s.")" "${dbfile##*/}.sig"
	else
		warning "$(gettext "Failed to sign package database.")"
	fi
}

# verify the existing package database signature
verify_signature() {
	(( ! VERIFY )) && return
	local dbfile="$1"
	local ret=0
	msg "$(gettext "Verifying database signature...")"

	if [[ ! -f $dbfile.sig ]]; then
		warning "$(gettext "No existing signature found, skipping verification.")"
		return
	fi
	gpg --verify "$dbfile.sig" || ret=$?
	if (( ! ret )); then
		msg2 "$(gettext "Database signature file verified.")"
	else
		error "$(gettext "Database signature was NOT valid!")"
		exit 1
	fi
}

verify_repo_extension() {
	local repofile=$1

	case "$repofile" in
		*.@(db|files).tar.gz)  TAR_OPT="z" ;;
		*.@(db|files).tar.bz2) TAR_OPT="j" ;;
		*.@(db|files).tar.xz)  TAR_OPT="J" ;;
		*.@(db|files).tar.Z)   TAR_OPT="Z" ;;
		*.@(db|files).tar)     TAR_OPT="" ;;
		*) error "$(gettext "'%s' does not have a valid archive extension.")" \
				"$repofile"
			exit 1 ;;
	esac

	printf '%s' "$TAR_OPT"
}

# write an entry to the pacman database
#   arg1 - path to package
db_write_entry() {
	# blank out all variables
	local pkgfile="$1"
	local -a _groups _licenses _replaces _depends _conflicts _provides _optdepends
	local pkgname pkgver pkgdesc csize size url arch builddate packager \
		md5sum sha256sum pgpsig pgpsigsize

	# read info from the zipped package
	local line var val
	while read -r line; do
		[[ ${line:0:1} = '#' ]] && continue
		IFS=' =' read -r var val < <(printf '%s\n' "$line")

		# normalize whitespace with an extglob
		declare "$var=${val//+([[:space:]])/ }"
		case "$var" in
			group)     _groups+=("$group") ;;
			license)   _licenses+=("$license") ;;
			replaces)  _replaces+=("$replaces") ;;
			depend)    _depends+=("$depend") ;;
			conflict)  _conflicts+=("$conflict") ;;
			provides)  _provides+=("$provides") ;;
			optdepend) _optdepends+=("$optdepend") ;;
		esac
	done< <(bsdtar -xOqf "$pkgfile" .PKGINFO)

	# ensure $pkgname and $pkgver variables were found
	if [[ -z $pkgname || -z $pkgver ]]; then
		error "$(gettext "Invalid package file '%s'.")" "$pkgfile"
		return 1
	fi

	if [[ -d $tmpdir/tree/$pkgname-$pkgver ]]; then
		warning "$(gettext "An entry for '%s' already existed")" "$pkgname-$pkgver"
	else
		if (( DELTA )); then
			pkgentry=$(find_pkgentry $pkgname)
			if [[ -n $pkgentry ]]; then
				local oldfilename=$(grep -A1 FILENAME $pkgentry/desc | tail -n1)
				local oldfile="$(dirname $1)/$oldfilename"
			fi
		fi
	fi

	# compute base64'd PGP signature
	if [[ -f "$pkgfile.sig" ]]; then
		pgpsigsize=$(@SIZECMD@ "$pkgfile.sig")
		if (( pgpsigsize > 16384 )); then
			error "$(gettext "Invalid package signature file '%s'.")" "$pkgfile.sig"
			return 1
		fi
		msg2 "$(gettext "Adding package signature...")"
		pgpsig=$(openssl base64 -in "$pkgfile.sig" | tr -d '\n')
	fi

	csize=$(@SIZECMD@ "$pkgfile")

	# compute checksums
	msg2 "$(gettext "Computing checksums...")"
	md5sum="$(openssl dgst -md5 "$pkgfile")"
	md5sum="${md5sum##* }"
	sha256sum="$(openssl dgst -sha256 "$pkgfile")"
	sha256sum="${sha256sum##* }"

	# remove an existing entry if it exists, ignore failures
	db_remove_entry "$pkgname"

	# create package directory
	pushd "$tmpdir/tree" >/dev/null
	mkdir "$pkgname-$pkgver"
	pushd "$pkgname-$pkgver" >/dev/null

	# restore an eventual deltas file
	[[ -f ../$pkgname.deltas ]] && mv "../$pkgname.deltas" deltas

	# create desc entry
	msg2 "$(gettext "Creating '%s' db entry...")" 'desc'
	{
		format_entry "FILENAME"  "${1##*/}"
		format_entry "NAME"      "$pkgname"
		format_entry "BASE"      "$pkgbase"
		format_entry "VERSION"   "$pkgver"
		format_entry "DESC"      "$pkgdesc"
		format_entry "GROUPS"    "${_groups[@]}"
		format_entry "CSIZE"     "$csize"
		format_entry "ISIZE"     "$size"

		# add checksums
		format_entry "MD5SUM"    "$md5sum"
		format_entry "SHA256SUM" "$sha256sum"

		# add PGP sig
		format_entry "PGPSIG"    "$pgpsig"

		format_entry "URL"       "$url"
		format_entry "LICENSE"   "${_licenses[@]}"
		format_entry "ARCH"      "$arch"
		format_entry "BUILDDATE" "$builddate"
		format_entry "PACKAGER"  "$packager"
		format_entry "REPLACES"  "${_replaces[@]}"
	} >'desc'

	# create depends entry
	msg2 "$(gettext "Creating '%s' db entry...")" 'depends'
	{
		format_entry "DEPENDS"    "${_depends[@]}"
		format_entry "CONFLICTS"  "${_conflicts[@]}"
		format_entry "PROVIDES"   "${_provides[@]}"
		format_entry "OPTDEPENDS" "${_optdepends[@]}"
	} >'depends'

	popd >/dev/null
	popd >/dev/null

	# create files file if wanted
	if (( WITHFILES )); then
		msg2 "$(gettext "Creating '%s' db entry...")" 'files'
		local files_path="$tmpdir/tree/$pkgname-$pkgver/files"
		echo "%FILES%" >$files_path
		bsdtar --exclude='^.*' -tf "$pkgfile" >>$files_path
	fi

	# create a delta file
	if (( DELTA )); then
		if [[ -n $oldfilename ]]; then
			if [[ -f $oldfile ]]; then
				delta=$(pkgdelta -q $oldfile $1)
				if [[ -f $delta ]]; then
					db_write_delta $delta
				fi
			else
				warning "$(gettext "Old package file not found: %s")" "$oldfilename"
			fi
		fi
	fi

	return 0
} # end db_write_entry

# remove existing entries from the DB
#   arg1 - package name
db_remove_entry() {
	local pkgname=$1
	local notfound=1
	local pkgentry=$(find_pkgentry $pkgname)
	while [[ -n $pkgentry ]]; do
		notfound=0
		if [[ -f $pkgentry/deltas ]]; then
			mv "$pkgentry/deltas" "$tmpdir/tree/$pkgname.deltas"
		fi
		msg2 "$(gettext "Removing existing entry '%s'...")" \
		"${pkgentry##*/}"
		rm -rf $pkgentry
		pkgentry=$(find_pkgentry $pkgname)
	done
	return $notfound
} # end db_remove_entry

elephant() {
	case $(( RANDOM % 2 )) in
		0) printf '%s\n' "H4sIAL3qBE4CAyWLwQ3AMAgD/0xh5UPzYiFUMgjq7LUJsk7yIQNAQTAikFUDnqkr" \
		                 "OQFOUm0Wd9pHCi13ONjBpVdqcWx+EdXVX4vXvGv5cgztB9+fJxZ7AAAA"
		;;

		1) printf '%s\n' "H4sIAJVWBU4CA21RMQ7DIBDbeYWrDgQJ7rZ+IA/IB05l69alcx5fc0ASVXUk4jOO" \
		                 "7yAAUWtorygwJ4hlMii0YkJKKRKGvsMsiykl1SalvrMD1gUXyXRkGZPx5OPft81K" \
		                 "tNAiAjyGjYO47h1JjizPkJrCWbK/4C+uLkT7bzpGc7CT9bmOzNSW5WLSO5vexjmH" \
		                 "ZL9JFFZeAa0a2+lKjL2anpYfV+0Zx9LJ+/MC8nRayuDlSNy2rfAPibOzsiWHL0jL" \
		                 "SsjFAQAA"
		;;
	esac | openssl base64 -d | gzip -d
}

check_repo_db() {
	local repodir

	# ensure the path to the DB exists
	if [[ "$LOCKFILE" == /* ]]; then
		repodir=${LOCKFILE%/*}/
	else
		repodir=$PWD/$LOCKFILE
		repodir=${repodir%/*}/
	fi

	if [[ ! -d "$repodir" ]]; then
		error "$(gettext "%s does not exist or is not a directory.")" "$repodir"
		exit 1
	fi

	# check lock file
	if ( set -o noclobber; echo "$$" > "$LOCKFILE") 2> /dev/null; then
		CLEAN_LOCK=1
	else
		error "$(gettext "Failed to acquire lockfile: %s.")" "$LOCKFILE"
		[[ -f $LOCKFILE ]] && error "$(gettext "Held by process %s")" "$(cat $LOCKFILE)"
		exit 1
	fi

	if [[ -f $REPO_DB_FILE ]]; then
		# there are two situations we can have here- a DB with some entries,
		# or a DB with no contents at all.
		if ! bsdtar -tqf "$REPO_DB_FILE" '*/desc' >/dev/null 2>&1; then
			# check empty case
			if [[ -n $(bsdtar -tqf "$REPO_DB_FILE" '*' 2>/dev/null) ]]; then
				error "$(gettext "Repository file '%s' is not a proper pacman database.")" "$REPO_DB_FILE"
				exit 1
			fi
		fi
		verify_signature "$REPO_DB_FILE"
		msg "$(gettext "Extracting database to a temporary location...")"
		bsdtar -xf "$REPO_DB_FILE" -C "$tmpdir/tree"
	else
		case "$cmd" in
			repo-remove)
			error "$(gettext "Repository file '%s' was not found.")" "$REPO_DB_FILE"
			exit 1
			;;
			repo-add)
			# check if the file can be created (write permission, directory existence, etc)
			if ! touch "$REPO_DB_FILE"; then
				error "$(gettext "Repository file '%s' could not be created.")" "$REPO_DB_FILE"
				exit 1
			fi
			rm -f "$REPO_DB_FILE"
			;;
		esac
	fi
}

add() {
	if [[ ! -f $1 ]]; then
		error "$(gettext "File '%s' not found.")" "$1"
		return 1
	fi

	if [[ ${1##*.} == "delta" ]]; then
		deltafile=$1
		msg "$(gettext "Adding delta '%s'")" "$deltafile"
		if ! type xdelta3 &>/dev/null; then
			error "$(gettext "Cannot find the xdelta3 binary! Is xdelta3 installed?")"
			exit 1
		fi
		if db_write_delta "$deltafile"; then
			return 0
		else
			return 1
		fi
	fi

	pkgfile=$1
	if ! bsdtar -tqf "$pkgfile" .PKGINFO >/dev/null 2>&1; then
		error "$(gettext "'%s' is not a package file, skipping")" "$pkgfile"
		return 1
	fi

	msg "$(gettext "Adding package '%s'")" "$pkgfile"

	db_write_entry "$pkgfile"
}

remove() {
	if [[ ${1##*.} == "delta" ]]; then
		deltafile=$1
		msg "$(gettext "Searching for delta '%s'...")" "$deltafile"
		if db_remove_delta "$deltafile"; then
			return 0
		else
			error "$(gettext "Delta matching '%s' not found.")" "$deltafile"
			return 1
		fi
	fi

	pkgname=$1
	msg "$(gettext "Searching for package '%s'...")" "$pkgname"

	if db_remove_entry "$pkgname"; then
		rm -f "$tmpdir/tree/$pkgname.deltas"
		return 0
	else
		error "$(gettext "Package matching '%s' not found.")" "$pkgname"
		return 1
	fi
}

trap_exit() {
	# unhook all traps to avoid race conditions
	trap '' EXIT TERM HUP QUIT INT ERR

	echo
	error "$@"
	clean_up 1
}

clean_up() {
	local exit_code=${1:-$?}

	# unhook all traps to avoid race conditions
	trap '' EXIT TERM HUP QUIT INT ERR

	[[ -d $tmpdir ]] && rm -rf "$tmpdir"
	(( CLEAN_LOCK )) && [[ -f $LOCKFILE ]] && rm -f "$LOCKFILE"

	exit $exit_code
}

# PROGRAM START

# determine whether we have gettext; make it a no-op if we do not
if ! type gettext &>/dev/null; then
	gettext() {
		echo "$@"
	}
fi

case "$1" in
	-h|--help) usage; exit 0;;
	-V|--version) version; exit 0;;
esac

# figure out what program we are
cmd=${0##*/}
if [[ $cmd == "repo-elephant" ]]; then
	elephant
	exit 0
fi

if [[ $cmd != "repo-add" && $cmd != "repo-remove" ]]; then
	error "$(gettext "Invalid command name '%s' specified.")" "$cmd"
	exit 1
fi

tmpdir=$(mktemp -d /tmp/repo-tools.XXXXXXXXXX) || (\
	error "$(gettext "Cannot create temp directory for database building.")"; \
	exit 1)
mkdir $tmpdir/tree

trap 'clean_up' EXIT
for signal in TERM HUP QUIT; do
	trap "trap_exit \"$(gettext "%s signal caught. Exiting...")\" \"$signal\"" "$signal"
done
trap 'trap_exit "$(gettext "Aborted by user! Exiting...")"' INT
trap 'trap_exit "$(gettext "An unknown error has occurred. Exiting...")"' ERR

declare -a args
success=0
# parse arguments
while (( $# )); do
	case "$1" in
		-q|--quiet) QUIET=1;;
		-d|--delta) DELTA=1;;
		-f|--files) WITHFILES=1;;
		-s|--sign)
			check_gpg
			SIGN=1
			if ! gpg --list-key ${GPGKEY} &>/dev/null; then
				if [[ ! -z $GPGKEY ]]; then
					error "$(gettext "The key ${GPGKEY} does not exist in your keyring.")"
				else
					error "$(gettext "There is no key in your keyring.")"
				fi
				exit 1
			fi
			;;
		-k|--key)
			check_gpg
			shift
			GPGKEY="$1"
			if ! gpg --list-key ${GPGKEY} &>/dev/null; then
				error "$(gettext "The key ${GPGKEY} does not exist in your keyring.")"
				exit 1
			fi
			;;
		-v|--verify)
			check_gpg
			VERIFY=1
			;;
		*)
			args+=("$1")
			;;
	esac
	shift
done

REPO_DB_FILE=${args[0]}
if [[ -z $REPO_DB_FILE ]]; then
	usage
	exit 1
fi

LOCKFILE=$REPO_DB_FILE.lck

verify_repo_extension "$REPO_DB_FILE" >/dev/null
check_repo_db

for arg in "${args[@]:1}"; do
	case "$cmd" in
		repo-add) add "$arg" ;;
		repo-remove) remove "$arg" ;;
	esac && success=1
done

# if at least one operation was a success, re-zip database
if (( success )); then
	msg "$(gettext "Creating updated database file '%s'")" "$REPO_DB_FILE"

	TAR_OPT=$(verify_repo_extension "$REPO_DB_FILE")
	filename=${REPO_DB_FILE##*/}

	pushd "$tmpdir/tree" >/dev/null
	if ( shopt -s nullglob; files=(*); (( ${#files[*]} )) ); then
		bsdtar -c${TAR_OPT}f "$tmpdir/$filename" *
	else
		# we have no packages remaining? zip up some emptyness
		warning "$(gettext "No packages remain, creating empty database.")"
		bsdtar -c${TAR_OPT}f "$tmpdir/$filename" -T /dev/null
	fi
	popd >/dev/null

	create_signature "$tmpdir/$filename"

	[[ -f $REPO_DB_FILE ]] && mv -f "$REPO_DB_FILE" "${REPO_DB_FILE}.old"
	if [[ -f $REPO_DB_FILE.sig ]]; then
		mv -f "$REPO_DB_FILE.sig" "$REPO_DB_FILE.old.sig"
	else
		rm -f "$REPO_DB_FILE.old.sig"
	fi
	[[ -f $tmpdir/$filename ]] && mv "$tmpdir/$filename" "$REPO_DB_FILE"
	[[ -f $tmpdir/$filename.sig ]] && mv "$tmpdir/$filename.sig" "$REPO_DB_FILE.sig"
	dblink="${REPO_DB_FILE%.tar*}"
	target=${REPO_DB_FILE##*/}
	rm -f "$dblink" "$dblink.sig"
	ln -s "$target" "$dblink" 2>/dev/null || \
		ln "$target" "$dblink" 2>/dev/null || \
		cp "$REPO_DB_FILE" "$dblink"
	if [[ -f "$REPO_DB_FILE.sig" ]]; then
		ln -s "$target.sig" "$dblink.sig" 2>/dev/null || \
			ln "$target.sig" "$dblink.sig" 2>/dev/null || \
			cp "$REPO_DB_FILE.sig" "$dblink.sig"
	fi
else
	msg "$(gettext "No packages modified, nothing to do.")"
	exit 1
fi

exit 0
# vim: set ts=2 sw=2 noet: