#!/usr/bin/perl
#
# Script for cleaning up backup dir used by backup-run.sh
# 
# Author:	Alan Briolat <alan.briolat@gmail.com>
#

# Include stuff that is needed
#use Getopt::Std;

# Set base backup dir
#$root_dir = "/backup/foo";
if($ARGV[0] =~ /(\/.+\/[^\/]+)(|\/)$/) {
	$root_dir = $1;
} else {
	print "Usage: backup-clean.pl directory [ filecount ]\n";
	exit;
}
# Number of recent backups to keep (1 = only latest)
$archive = 1;
if($ARGV[1] =~ /[0-9]+/) {
	$archive = $ARGV[1];
}

# Open the directory, otherwise kill the script
opendir(DIR, $root_dir) || die "Could not open $root_dir: $!";

# List all of the files in an array and sort in ascending order (newest last)
@filelist = grep { !/^\./ } readdir(DIR);
@filelist = sort(@filelist);

# Iterate through the file list
my @files;
foreach (@filelist) {
	# Backup filename
	$file = $_;
	# Grab parts of the filename
	/([\w]+)-(.*?)-([\d]{4})-([\d]{2})-([\d]{2})-([\d]{2})([\d]{2})\.tar\.bz2/;
	# Create hash key
	$key = "$1-$2";
	# If array doesnt exist create it
	if(not ref($files{$key}) eq "ARRAY") {
		@{ $files{$key} } = ();
	}
	# Push the file onto the array
	push(@{ $files{$key} }, $file);
	#print "Added $6:$7 $3-$4-$5 to $1-$2\n";
}

foreach(keys(%files)) {
	#print "$_\n";
	# Pop the defined number of files off the list
	# (ones left on the list get deleted)
	for($i = 0; $i < $archive; $i++) {
		pop(@{$files{$_}});
	}
	
	# Delete files that are left
	foreach(@{$files{$_}}) {
		#print "\t$_\n";
		system(("rm", "$root_dir/$_"));
	}
}