#!/bin/sh

# lbu - utility to create local backups.
# Copyright (c) 2006 Natanael Copa
# May be distributed under GPL2

PREFIX=
. $PREFIX/lib/libalpine.sh
# this one is from apk-tools
. $PREFIX/lib/apk/libutil.sh

VERSION=0.8
[ "$SFIC" ] && SFIC="$SFIC -i d"

# globals
CURRENT_TDB="$APK_CACHE/current.tdb"
TMPCURRENT_TDB="$APK_CACHE/tmp-current.tdb"
COMMITED_TDB="$APK_CACHE/commited.tdb"

EXCLUDE_LIST=/etc/lbu/exclude
INCLUDE_LIST=/etc/lbu/include

MASK="Npugsh"

LBUDIRS=`echo "$APK_LBUDIRS" | sed 's/:/ /g'`

retcode=0
usage() {
	echo "$PROGRAM $VERSION"
	echo "usage: $PROGRAM <subcommand> [options] [args]

Available subcommands:
  commit (ci)
  exclude (ex, delete)
  include (inc, add)
  status (stat, st)
  update (up)

Common options:
 -h	Show help for subcommand.
 -q	Quiet mode.
 -v	Verbose mode.
"
	exit 1
}


#gen_temp_tdb() {
#	# generate temp tdb
#	local opwd="$PWD"
#	rm -f "$TMP_TDB"
#	cd "$ROOT"
#	$SFIC -R --add "$TMP_TDB" $LBUDIRS
#	cd "$opwd"
#}	

gen_current_tdb() {
#	[ -f "$TMP_TDB" ] || gen_temp_tdb
	# generate current tdb
	rm -f "$CURRENT_TDB"
	$SFIC -R -t --mask "$MASK" --old "$APK_DEFAULT_TDB" $LBUDIRS \
		| grep -v ^D | awk '{print $2}' | $SFIC --add $CURRENT_TDB --file -
}

# list_add(char *listfile, char* file...)
list_add() {
	local list="$1"
	shift
	mkdir -p `dirname "$list"`
	while [ $# -gt 0 ] ; do
		filename=`echo "$1" | sed 's:^/\+::'`
		if grep "^$filename$" "$list" >/dev/null 2>&1 ; then
			[ "$VERBOSE" ] echo "$filename is already in $list."
		else
			[ "$VERBOSE" ] && echo "Adding $filename to $list."
			echo "$filename" >> "$list"
		fi
		shift
	done
}

# list_delete(char *listfile, char *file...)
list_delete() {
	local list="$1"
	local tmp="$list.old"
	shift
	[ -f "$list" ] || return 1
	while [ $# -gt 0 ] ; do
		filename=`echo "$1" | sed 's:^/\+::'`
		mv "$list" "$tmp"
		[ "$VERBOSE" ] && echo "Removing $filename from list."
		grep -v "^$filename$" "$tmp" > "$list"
		rm "$tmp"
		shift
	done
}


		
#
# lbu_include - add/remove files to include list
#
usage_include() {
	echo "$PROGRAM $VERSION
usage: $PROGRAM include [-rv] <file> ...
       $PROGRAM include [-v] -l

Options:
  -l	List contents of include list.
  -r	Remove specified file(s) from include list instead of adding.
  -v	Verbose mode.
"
	exit 1
}

cmd_include() {
	if [ "$LIST" ] ; then
		[ $# -gt 0 ] && usage_include
		show_include
		return
	fi
	
	[ $# -lt 1 ] && usage_include
	if [ "$REMOVE" ] ; then
		list_delete "$INCLUDE_LIST" "$@"
	else
		list_add "$INCLUDE_LIST" "$@"
		list_delete "$EXCLUDE_LIST" "$@"
	fi
}

show_include() {
	if [ -f "$INCLUDE_LIST" ] ; then
		[ "$VERBOSE" ] && echo "Include files:"
		cat "$INCLUDE_LIST"
	fi
}


#
# lbu_commit - commit config files to writeable media
#
usage_commit() {
	echo "$PROGRAM $VERSION
usage: $PROGRAM commit [-nv] [<media>]

Options:
  -n	Don't commit, just show what would have been commited.
  -v	Verbose mode.

The following values for <media> is supported: floppy usb
If <media> is not specified, the environment variable LBU_MEDIA will be used.
"
	exit 1
}

cmd_commit() {
	local media mnt was_mounted statuslist tmplist currentlist 
	local incl excl outfile
	
	if [ "$1" ] ; then
		media="$1"
	else
		media="$LBU_MEDIA"
	fi
	[ -z "$media" ] && usage_commit

	mnt=/media/$media

	[ -d $mnt ] || usage
	was_mounted=`grep $mnt /proc/mounts`

	cd "$ROOT"

	# for upgrading from packages.list times
	if [ ! -f "$INCLUDE_LIST" ] ; then
		mkdir -p $(dirname "$INCLUDE_LIST")
		echo "var/lib/apk/world" > "$INCLUDE_LIST"
	fi
	
	# Automatically add list and modified files
	currentlist=`VERBOSE="" USE_DEFAULT="-a" cmd_status -a | grep -v ^D | awk '{print $2}'`

	if [ -z "$was_mounted" ]; then
		mount $mnt || die "failed to mount $mnt."
	fi

	# we generate a tmpcurrent before we commit to avoid race condition
	[ -f "$CURRENT_TDB" ]  || $SFIC --add "$CURRENT_TDB" $currentlist
	
	# commit files to archive
	if [ "$DRYRUN" ] ; then
		outfile=/dev/null
		VERBOSE="-v"
	else
		outfile="$mnt/`hostname`.apkovl.tar.gz"
	fi
	
	[ -f "$EXCLUDE_LIST" ] && excl="-X $EXCLUDE_LIST"
	[ -f "$INCLUDE_LIST" ] && incl="-T $INCLUDE_LIST"
	
	if ! tar $VERBOSE $excl $incl -c $currentlist | gzip -c  >"$outfile" ; then
		rm -f "$CURRENT_TDB"
		[ -z "$was_mounted" ] && umount $mnt
		die "Problems creating archive. aborting"
	fi	

	# remove obsolete file
	if [ -z "$DRYRUN" ] ; then
		rm -f $mnt/packages.list
	fi

	sync
	sleep 1
	[ -z "$was_mounted" ] && umount $mnt

	# move current to commited.
	[ "$DRYRUN" ] || mv "$CURRENT_TDB" "$COMMITED_TDB"
}

#---------------------------------------------------------------------------
# lbu_exclude - add remove file(s) from exclude list

usage_exclude() {
	echo "$PROGRAM $VERSION
usage: $PROGRAM exclude [-rv] <file> ...
       $PROGRAM exclude [-v] -l

Options:
  -l	List contents of exclude list.
  -r	Remove specified file(s) from exclude list instead of adding.
  -v	Verbose mode.
"
	exit 1
}

cmd_exclude() {
	if [ "$LIST" ] ; then
		[ $# -gt 0 ] && usage_exclude
		show_exclude
		return
	fi
	
	[ $# -lt 1 ] && usage_exclude
	if [ "$REMOVE" ] ; then
		list_delete "$EXCLUDE_LIST" "$@"
	else
		list_delete "$INCLUDE_LIST" "$@"
		list_add "$EXCLUDE_LIST" "$@"
	fi
}

show_exclude() {
	if [ -f "$EXCLUDE_LIST" ] ; then
		[ "$VERBOSE" ] && echo "Exclude files:"
		cat "$EXCLUDE_LIST"
	fi	
}

#---------------------------------------------------------------------------
# lbu_status - check what files have been changed since last save
usage_status() {
	echo "$PROGRAM $VERSION
Check what files have been changed since last commit.

usage: $PROGRAM status [-M <MASK>] [-av]

Options:
  -M	Use a different mask for comparing. (see sfic -h)
  -a	Compare all files, not just since last commit.
  -v	Also show include and exclude lists.
"
	exit 1
}

cmd_status() {
	cd "$ROOT"

	[ "$SFIC" ] || die "Need sfic."
	[ -f "$APK_DEFAULT_TDB" ] || die "$APK_DEFAULT_TDB not found."

	# genereate temp tdb
	#gen_temp_tdb
	
	if [ -f "$COMMITED_TDB" ] && [ -z "$USE_DEFAULT" ]; then
		# generate current tdb
		gen_current_tdb
		OLD="$COMMITED_TDB"
		NEW="--new $CURRENT_TDB"
	else
		OLD="$APK_DEFAULT_TDB"
		NEW="-R $LBUDIRS"
	fi

	$SFIC $QUIET $VERBOSE --mask "$MASK" -t --old "$OLD" $NEW
	retcode=$?

	if [ "$VERBOSE" ] ; then
		echo ""
		show_include
		echo ""
		show_exclude
	fi
}

#------------------------------------------------
# lbu_update - Update the database wihtout commit to media.
usage_update() {
	echo "$PROGRAM $VERSION
Update the commited database without commit to media.
	
usage: $PROGRAM update [-v] <file> ...

Options:
  -v	Verbose mode.
"
	exit 1
}

cmd_update() {
	[ $# -lt 1 ] && usage_update
	cd "$ROOT"
	for i in "$@" ; do
		echo $i | sed 's:^/::'
	done | lbu_filter | $SFIC $VERBOSE --add "$COMMITED_TDB" --file -
}

#-----------------------------------------------------------
# Main

cmd=`echo "$PROGRAM" | cut -s -d_ -f2`
PROGRAM=`echo "$PROGRAM" | cut -d_ -f1`
if [ -z "$cmd" ] ; then
	cmd="$1"
	[ -z "$cmd" ] && usage
	shift
fi

# check for valid sub command
case "$cmd" in
	include|inc|add)	SUBCMD="include";;
	commit|ci)		SUBCMD="commit";;
	exclude|ex|delete)	SUBCMD="exclude";;
	status|stat|st)		SUBCMD="status";;
	update|up)		SUBCMD="update";;
	*)			usage;;
esac

# parse common args
while getopts "ahlM:nqrv" opt ; do
	case "$opt" in
		a) 	[ $SUBCMD = status ] || usage_$SUBCMD
			USE_DEFAULT="-a"
			;;
		h) 	usage_$SUBCMD
			;;
		l)	LIST="-l"
			;;
		M) 	[ $SUBCMD = status ] || usage_$SUBCMD
			MASK="$OPTARG"
			;;
		n) 	[ $SUBCMD = commit ] || usage_$SUBCMD
			DRYRUN="-n"
			;;
		q)	QUIET="$QUIET -q"
			;;
		r)	REMOVE="-r"
			;;
		v) 	VERBOSE="$VERBOSE -v"
			;;
	esac
done
shift `expr $OPTIND - 1`
			
cmd_$SUBCMD "$@"		
# cleanup
rm -f "$CURRENT_TDB"
exit $retcode