#!@@@perl@@@ -w
#
# $Id: agestat.pl,v 1.10 2015-08-25 16:00:39 hjp Exp $
#

use strict;
use File::stat;
use File::Find;
use Getopt::Long;

sub usage {
    print STDERR "Usage: $0 [-atime|-mtime] [-scale=(k|M)] [-buckets=(cal|log2)]\n";
    exit 1;
}

my $now = time();
my @bucket_max;

my %opts = (buckets => 'log2');
GetOptions(\%opts, "atime", "mtime", "scale=s", "buckets=s") or usage();
my $scale;
if (!defined($opts{scale})) {
    $scale = 1;
} elsif ($opts{scale} eq 'k') {
    $scale = 1024;
} elsif ($opts{scale} eq 'M') {
    $scale = 1024*1024;
} else {
    usage();
}

if ($opts{buckets} eq "log2") {
    for (my ($b, $s) = (0, 1); $b < 32; $b++, $s *= 2) {
	$bucket_max[$b] = $s;
    }
} elsif ($opts{buckets} eq "cal") {
    @bucket_max = (
	3600,
	86400,
	7 * 86400,
	30 * 86400,
	182 * 86400,
	1 * 365.2422 * 86400,
	2 * 365.2422 * 86400,
	3 * 365.2422 * 86400,
	4 * 365.2422 * 86400,
	5 * 365.2422 * 86400,
    );
} elsif ($opts{buckets} =~ /^days=(\d+)/) {
    @bucket_max = map $_ * 86400, (1 .. $1);
} elsif ($opts{buckets} =~ /^hours=(\d+)/) {
    @bucket_max = map $_ * 3600, (1 .. $1);
} else {
    usage();
}


my @hist;

sub wanted {

    my $st = lstat($_);
    return unless $st;
    my $age = $now - (
	$opts{atime} ? $st->atime :
	$opts{mtime} ? $st->mtime :
		       (! -d && $st->atime > $st->mtime ? $st->atime
		                                        : $st->mtime ));
    my $b = 0;
    while ($b <= $#bucket_max && $age > $bucket_max[$b]) { $b++ };
    #print $File::Find::name, ": $age sec, ", $st->size, " bytes, ", $st->nlink, " links, bucket $b\n";
    $hist[$b] += $st->size / $st->nlink;
}

sub time2str {
    my ($t) = (@_);

    if ($t < 60) {
	return sprintf ("%6.1f s", $t);
    } elsif ($t < 3600) {
	return sprintf ("%6.1f m", $t/60);
    } elsif ($t < 3600 * 24) {
	return sprintf ("%6.1f h", $t/3600);
    } elsif ($t < 3600 * 24 * 365.2422) {
	return sprintf ("%6.1f d", $t/(3600*24));
    } else {
	return sprintf ("%6.1f y", $t/(3600*24*365.2422));
    }
}



if (@ARGV == 0) { push (@ARGV, "."); }
find(\&wanted, @ARGV);

print "\n\n";

my $sum = 0;

for (my $i = 0; $i <= $#hist; $i++) {
    $sum += ($hist[$i] || 0);
}


my $c = 0;
for (my $i = 0; $i <= $#hist; $i++) {
    my $h = ($hist[$i] || 0);
    $c += $h;
    printf("%2d\t%s\t%12.0f\t%5.1f\t%12.0f\t%5.1f\n",
	   $i,
	   $i <= $#bucket_max ? time2str($bucket_max[$i]) : "infinity",
	   $h/$scale, $h * 100 / $sum, $c/$scale, $c * 100 / $sum);
}

# $Log: agestat.pl,v $
# Revision 1.10  2015-08-25 16:00:39  hjp
# New bucket type days
#
# Revision 1.9  2012-10-22 09:20:05  hjp
# fixed usage message
#
# Revision 1.8  2007-02-09 15:36:37  hjp
# Automatically create GNUmakerules and GNUmakevars if they don't exist.
# Print usage if unknown option is given.
#
# Revision 1.7  2006/02/17 13:50:23  hjp
# Fixed error when oldest file was older than oldest bucket.
# Realigned columns.
#
# Revision 1.6  2006/02/17 13:31:41  hjp
# Added option --buckets.
#
# Revision 1.5  2002/03/18 20:33:46  hjp
# Ignore atime for directories
#
# Revision 1.4  2001/01/19 19:06:01  hjp
# Removed superfluous "total" line.
# Fixed usage message.
#