#!/bin/bash
###########################################################
# set prefix=, from= and to= in backup.cfg ...

                                        test -e "$0.cfg"                   || exit 1;
source $0.cfg;                          test -z "$prefix"                  && exit 2;
                                        test -z "$from"                    && exit 3;
cd /;                                   test -d "$to"                      || exit 4;

today=$(date +"%Y-%m-%d");              test -e "$to/$prefix-$today.tgz"   && exit 0;
ago1d=$(date +"%Y-%m-%d" -d "-1 day");  test -e "$to/$prefix-$today-d.tgz" && exit 0;
ago1w=$(date +"%Y-%m-%d" -d "-1 week"); test -e "$to/$prefix-$today-w.tgz" && exit 0;
ago4w=$(date +"%Y-%m-%d" -d "-4 week"); test -e "$to/$prefix-$today-m.tgz" && exit 0;
ago3m=$(date +"%Y-%m-%d" -d "-3 months");
wkday=$(date +"%w-%d");

case "$wkday" in
	
 *-01-01.tgz) ;&  # keep full backups of Jan, Apr, Jun and Oct
 *-04-01.tgz) ;&
 *-07-01.tgz) ;&
 *-10-01.tgz)

       echo "Monthly full backup $to/$prefix-$today.tgz";
       echo;
       tar -cvvzf                $to/$prefix-$today.tgz   --totals                $from|grep -v /$ -;
       ;;

 *-01) echo "Monthly full backup $to/$prefix-$today-m.tgz";
       echo;
       tar -cvvzf                $to/$prefix-$today-m.tgz --totals                $from|grep -v /$ -;
       ;;

 0-??) echo "Weekly backup $to/$prefix-$today-w.tgz (files since $ago1w)";
       echo;
       tar -cvvzf          $to/$prefix-$today-w.tgz --totals -N "$ago1w 00:00:00" $from|grep -v /$ -;
       ;;

    *) echo "Daily backup $to/$prefix-$today-d.tgz (files since $ago1d)";
       echo;
       tar -cvvzf         $to/$prefix-$today-d.tgz  --totals -N "$ago1d 00:00:00" $from|grep -v /$ -;
       ;;
esac                                       >"$to/backup.log"; 2>"$to/backup.tmp"

grep -v "ndert; nicht gesichert."                               "$to/backup.tmp" >"$to/backup.err";
rm                                                              "$to/backup.tmp";

echo                                      >>"$to/backup.log";

if test -e     "$to/$prefix-$ago1w-d.tgz"; then
 echo "removing $to/$prefix-$ago1w-d.tgz" >>"$to/backup.log";
 rm            "$to/$prefix-$ago1w-d.tgz" >>"$to/backup.log"                   2>>"$to/backup.err";
fi

if test -e     "$to/$prefix-$ago4w-d.tgz"; then
 echo "removing $to/$prefix-$ago4w-d.tgz" >>"$to/backup.log";
 rm            "$to/$prefix-$ago4w-d.tgz" >>"$to/backup.log"                   2>>"$to/backup.err";
fi

if test -e     "$to/$prefix-$ago4w-w.tgz"; then
 echo "removing $to/$prefix-$ago4w-w.tgz" >>"$to/backup.log";
 rm            "$to/$prefix-$ago4w-w.tgz" >>"$to/backup.log"                   2>>"$to/backup.err";
fi

if test -e     "$to/$prefix-$ago3m-w.tgz"; then
 echo "removing $to/$prefix-$ago3m-w.tgz" >>"$to/backup.log";
 rm            "$to/$prefix-$ago3m-w.tgz" >>"$to/backup.log"                   2>>"$to/backup.err";
fi

if test -e     "$to/$prefix-$ago3m-m.tgz"; then
 echo "removing $to/$prefix-$ago3m-m.tgz" >>"$to/backup.log";
 rm            "$to/$prefix-$ago3m-m.tgz" >>"$to/backup.log"                   2>>"$to/backup.err";
fi

cat "$to/backup.log"; echo;                                                   cat "$to/backup.err"; 

exit 0;