#!/usr/bin/perl


# our needed packages
use strict "vars";
use Getopt::Std;

my $VERBOSE = 0;
my $DEBUG = 0;
my $SIMULATE = 0;

# Global Variables 

my $ITERATIONS = 3;
my $CONFIG;

# add support for config file
my $opt_string = "vdhsc:";
getopts( "$opt_string", \my %opt) or usage() and exit(1);

$VERBOSE = 1 if $opt{'v'};
$DEBUG = 1 if $opt{'d'};
if ( $opt{'h'} ){
    usage();
    exit 0;
}
$SIMULATE = $opt{s};

$CONFIG = $opt{c};

usage() and die("you have to supply a config file. please.\n") unless $CONFIG;

# $LOCAL = $HOST unless $LOCAL;
# debug("Checking if host is up and folder is present\n");
# die("The remote host could not verify the directory $DIR or is down. Exiting.\n") unless verify_host($HOST,$DIR,$USER);

    
##########################################################
# main part

# for all hosts: ( also for every line)
open(CONF,"$CONFIG") or die("unable to open config $CONFIG: $!\n");
while( my $line = <CONF> ){
    my $HOST;
    my $LIST;
    if ( $line =~ /(\s+):(.*)/ ){
	$HOST = $1;
	$LIST = $2;
	debug("read line with host: '$HOST' and dirs: '$LIST'\n");
    } else {
	next;
	}
    
    my $LOCAL = $HOST;
# remove the oldest if number equals $ITERATIONS
    if ( stat($LOCAL . "." . $ITERATIONS) ){
	run_command("rm -rf " . $LOCAL . "." . $ITERATIONS);
    }

# rotate the folders from 1 until the end, backwards

    for ( my $i = ( $ITERATIONS -1); $i >= 1; $i--){
	if ( stat($LOCAL . "." , $i)){
	    run_command("mv " . $LOCAL . "." . $i . " " . $LOCAL . "." . ( $i + 1));    
	}
    }

# copy with hard links base folder to .1
    run_command("cp -al " . $LOCAL . " " . $LOCAL . ".1");

# execute rsync

# for every folder
    my @FOLDERS = split /,/,$LIST;
    foreach my $DIR ( @FOLDERS ){
      run_command("rsync -a -v --delete -e ssh $HOST:$DIR $LOCAL");
    }

}
# debug("script is finished, exiting...\n");
# exit 0;
    
##################################################
sub usage {
    print "usage:\n";
    print "-h for help\n";
    print "-v for verbose ( more output )\n";
    print "-d for debug ( even more output)\n";
    print "-s simulate only , do not execute\n";
    print "----\n";
    print "-c <config> in order to supply the backup file\n";
}

sub verbose {
    print "VERBOSE: " . $_[0] if  $VERBOSE or $DEBUG ;
}    
sub debug {
    print "DEBUG: " . $_[0] if  $DEBUG ;
}    
     
# sub verify_host {
    
#    my $host = $_[0];
#    my $dir = $_[1];
#    my $user = $_[2];
    
#    $host = $user . "@" . $host if $user;
#    open(SSH,"ssh $host stat $dir |");
#    while ( my $line = <SSH> ){
#	if ( $line =~ /Modify: / ){
#	    close(SSH);
#	    return 1;
# }
#	}
#    close(SSH);
#    return 0;
    
# }

sub run_command {
    
    my $command = $_[0];
    debug("EXEC: " . $command . "\n");
    system($command) unless $SIMULATE;
    
}