#!/usr/bin/perl -w
#
# Copyright (C) 2003 by Bill Allombert <ballombe@debian.org>

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

# based on a design and a bash/gawk script 
# 
# Copyright (C) 1998,2000 by Avery Pennarun, for the Debian Project.
# Use, modify, and redistribute modified or unmodified versions in any
# way you wish.

use strict;
use 5.6.0;  

my $dpkg_db="/var/lib/dpkg/info";
my $popcon_conf="/etc/popularity-contest.conf";

my %opts=();

# $popcon_conf is in shell-script format
my $HOSTID = qx(unset MY_HOSTID; . $popcon_conf; echo \$MY_HOSTID );

chomp $HOSTID;

if ( $HOSTID eq "")
{
  print STDERR "You must set MY_HOSTID in $popcon_conf!\n";
  exit 1;
}

if ( $HOSTID eq "d41d8cd98f00b204e9800998ecf8427e")
{
  print STDERR "Warning: MY_HOSTID is the md5sum of the empty file!\n";
  print STDERR "Please change it to the md5sum of a random file in $popcon_conf!\n";
}

if ( $HOSTID !~ /^([a-f0-9]{32})$/)
{
  print STDERR "Error: MY_HOSTID does not match ^([a-f0-9]{32})\$\n";
  print STDERR "Please edit $popcon_conf to use a valid md5sum value\n";
  exit 1;
}

# Architecture.
my $debarch = `dpkg --print-installation-architecture`;
chomp $debarch;

# Set if dpkg package version is older than 1.10, thus missing dpkg-query.
my $olddpkg = 0;
if ( ! -x "/usr/bin/dpkg-query" ) {
    $olddpkg = 1;
}

# Popcon release
my $popconver;
if ($olddpkg) {
    $popconver = `dpkg-awk "Package: *popularity-contest.*" -- Version|grep ^Version|sed 's/^Version: //'`;
} else {
    $popconver=`dpkg-query --showformat='\${version}' --show popularity-contest 2>/dev/null`;
}

# Initialise time computations

my $now = time;
my $daylen = 24 * 60 * 60;
my $monthlen = $daylen * 30;
my $lastmonth = $now - $monthlen;

my %popcon=();

#Read dpkg database of installed packages
if ($olddpkg) {
    open PACKAGES, "dpkg-awk 'Status: .* installed' -- Package | grep '^Package:' | sed 's/^Package: /install ok installed /'|";
} else {
    open PACKAGES, "dpkg-query --show --showformat='\${status} \${package}\\n'|";
}
while (<PACKAGES>)
{
  /^.*installed *(.+)$/ or next;
  my $pkg=$1;
  $popcon{$pkg}=[0,0,$pkg,"<NOFILES>"];
  open FILES, "$dpkg_db/$pkg.list";
  my $bestatime = undef;
  while (<FILES>)
  {
    chop;
    m{/bin/|/sbin/|^/usr/games/|\.[ah]$|\.pm$} or next;
    -f $_ or next;
    my($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
                      $atime,$mtime,$ctime,$blksize,$blocks)
                          = stat;
    print STDERR if (!defined($atime));
    if (!defined($bestatime) || $atime >= $bestatime)
    {
      $bestatime=$atime;
      if ($atime < $lastmonth)
      { 
        # Not accessed since more than 30 days.
        $popcon{$pkg}=[$atime,$ctime,$pkg,$_,"<OLD>"];
      }
      elsif ($ctime > $lastmonth && $atime-$ctime < $daylen)
      {
        # Installed/upgraded less than a month ago and not used after 
        # install/upgrade day.
        $popcon{$pkg}=[$atime,$ctime,$pkg,$_,"<RECENT-CTIME>"];
      }
      else
      {
        # Else we `vote' for the package.
        $popcon{$pkg}=[$atime,$ctime,$pkg,$_];
      }
    }
  }
  close FILES;
}

close PACKAGES;

# We're not done yet.  Sort the output in reverse by atime, and
# add a header/footer.
	
print "POPULARITY-CONTEST-0 TIME:",time," ID:$HOSTID ".
    "ARCH:$debarch POPCONVER:$popconver\n";

for (sort { $popcon{$b}[0] <=> $popcon{$a}[0] } keys %popcon)
{
  print join(' ',@{$popcon{$_}}),"\n";
}

print "END-POPULARITY-CONTEST-0 TIME:",time,"\n";
