#!/bin/sh

# Defaults
HOSTNAME=`hostname`
BACKUPLOCATION="/usr/backup"
BYHOSTNAME=1
RSYNC_RSH="ssh"
RSYNC_OPTS=
QUIET=0
RECURSIVE=0
VERBOSE=0
COMMAND="backup"

[ -f "/usr/local/etc/pmb.rc" ] && . /usr/local/etc/pmb.rc
[ -f "./pmb.rc" ] && . pmb.rc

OPTS=`getopt RBCSqvrh: $*`
if [ "$?" -ne "0" ]; then
	echo "Bad usage" >&2
	exit 1
fi

set -- $OPTS

while [ $# -gt 0 ]; do
	case $1 in
		-q) QUIET=1 ;;
		-v) VERBOSE=1 ;;
		-r) RECURSIVE=1 ;;
		-h) HOSTNAME=$2; shift ;;
		-C) COMMAND="checkfile" ;;
		-B) COMMAND="backup" ;;
		-R) COMMAND="recover" ;;

		-S) COMMAND="rotate" ;;

		--) shift; break ;;
	esac
	shift
done

# Don't let the rc file override these 
RSYNC_OPTS="-a --delete --link-dest=../backup.1"
BACKUPDIR=`echo $BACKUPLOCATION | sed -e 's/^.*://'`

if [ "$BYHOSTNAME" -eq 1 ]; then
	BACKUPLOCATION="${BACKUPLOCATION}/${HOSTNAME}"
	BACKUPDIR="${BACKUPDIR}/${HOSTNAME}"
fi

warn() {
	echo "$@" 1>&2
}

fatal() {
	warn "Error: $@"
	exit 1
}

# This should only be run on the backup server itself
shiftdirs() {
	mkdir -p $BACKUPDIR
	CWD=$PWD
	cd $BACKUPDIR
	pwd
	DIRS=`find backup.* -type d -name 'backup.*' -maxdepth 0 2> /dev/null| sort -rn -t '.' -k 2`
	if [ ! -z "$DIRS" ]; then
		for i in $DIRS; do
			[ ! -d "$i" ] && fatal "$i is not a directory."
			DEST=${i%%.*}.$((${i##*.} + 1))
			echo ": $i -> $DEST"
			mv $i $DEST
		done
	fi

	# Only keep 19 backups?
	rm -rf backup.20

	mkdir backup.0
	cd $CWD
	pwd
}

normalize_path() {
	P=$1
	TMP=`realpath $P`
	if [ $? -eq 0 ]; then
		P=$TMP
	else 
		[ "${P#/}" = "${P}" ] && P=$PWD/$P
	fi
	echo "$P"
}

normalize_all() {
	while [ $# -gt 0 ]; do
		normalize_path $1
		shift
	done
}

rotate_backups() {
	SERVER=`echo $BACKUPLOCATION | awk -F: '{print $1}'`

	#echo "Backup location: $BACKUPLOCATION"

	# If backup is local, awk won't grok anything
	if [ "$SERVER" = "$BACKUPLOCATION" ]; then
		echo "LOCAL!!!"
		$0 -S
	else
		# Remote backup server
		echo "**** REMOTE!!!"
		ssh ${USER}@$SERVER "pmb -S -h $HOSTNAME" | sed -e 's/^/rotate: /'
	fi
}

do_backup() {
	BTMP="/tmp/backup.$USER.$$"

	if [ $# -eq 0 ]; then
		find $TARGETS > $BTMP
	else
		find `normalize_all $*` > $BTMP
	fi

	echo "ROTATING"
	rotate_backups
	echo "ROTATION DONE"

	# Do the backup
	rsync -v $RSYNC_OPTS --files-from=$BTMP / ${BACKUPLOCATION}/backup.0

	[ -f "$BTMP" ] && rm $BTMP
}

do_checkfile() {
	BTMP="/tmp/backup.$USER.check"
	#echo "Backup: $BACKUPLOCATION"

	[ -z "$*" ] && echo "No files specified, using '.'" && set -- .

	normalize_all $* > $BTMP

	sed -e 's/^/Checking: /' $BTMP
	echo
	rsync -rvna --files-from="$BTMP" ${BACKUPLOCATION}/backup.0 / 2> $BTMP.err \
		| grep -v '^receiving file' | sed -ne '/^$/q;p' > $BTMP.1

	FILESCHANGED=`wc -l $BTMP.1 | awk '{print $1}`
	if [ "$FILESCHANGED" -gt 0 ]; then
		echo "Files changed:"
		sed -e 's/^/   /' $BTMP.1
	else
		echo "No files changed"
	fi

	cat $BTMP.err

	rm $BTMP $BTMP.1 $BTMP.err 
}

do_recover() {
	BTMP="/tmp/backup.$USER.check"

	[ -z "$*" ] && echo "No files specified, using '.'" && set -- .

	do_checkfile $* | sed -e 's/^/=>  /'
	normalize_all $* > $BTMP

	echo "This will delete the existing files"
	echo -n "Are you sure you want to do this? (y/n) "
	read y

	case $y in
		[yY]|[yY][eE][sS]) ;;
		*) echo "Cancelled"; return ;;
	esac

	rsync -rva --files-from="$BTMP" ${BACKUPLOCATION}/backup.0 / 2> $BTMP.err \
		| grep -v '^receiving file' | sed -ne '/^$/q;p' | sed -e 's/^/Restoring: /'

	

	if wc -l $BTMP.err | awk '($1 == 0) { exit(1) }'; then
		echo "Errors:"
		cat $BTMP.err | sed -e 's/^/   /'
	fi

	rm $BTMP $BTMP.err
}

do_rotate() {
	shiftdirs
}

case $COMMAND in
	backup) do_backup $* ;;
	checkfile) do_checkfile $* ;;
	recover) do_recover $* ;;
	rotate) do_rotate $* ;;
esac