#!/usr/bin/perl
################################################################################
#
# File:         $RCSfile: weed,v $
# Revision:	$Revision: 1.1 $
# Description:  Weed out obvious spams from the mail store
# Author:       Andrew@DeFaria.com
# Created:      Mon Feb 19 22:37:30 CST 2007
# Modified:     $Date: 2013/06/12 14:05:47 $
# Language:     perl
#
# (c) Copyright 2007, Andrew@DeFaria.com, all rights reserved.
#
################################################################################
use strict;
use warnings;

use lib $FindBin::Bin, '/opt/clearscm/lib';

use Getopt::Long;

use MAPS;

use Display;
use Utils;

my $mailstore = "/var/spool/exim/input";

sub Usage {
  display "Usage: weed: [ -v|erbose ] [ -d|ebug ]\n";
  display "Where:";
  display "  -v|erbose\tTurn on verbose mode (default off)";
  display "  -d|ebug\tTurn on debug mode (default off)";
  display "  -u|sage\tDisplay this usage message";
  exit 1;
} # usage

# Just me
my $userid = "andrew";

my ($username, $user_email) = SetContext $userid;

sub GetEmailsInSpool () {
  my %emails;

  # Open mailstore directory. Note must have read access to this
  # directory and the files in this directory. IOW we probably need to
  # be running as root. Also, the MTA should not be running because we
  # may be removing files...
  opendir MAILSTORE, $mailstore
    or error "Unable to open mailstore $mailstore - $!", 1;

  # Weed out . and ..
  my @msgs = grep {!/^\./} readdir MAILSTORE;

  # Don't need the directory opened anymore...
  closedir MAILSTORE;

  # Select only the "-H" header files...
  @msgs = grep {/-H$/} @msgs;

  # Now search for "From:" in the header files, extract email address
  # and put into return hash.
  my $msg_nbr;

  foreach (@msgs) {
    $msg_nbr = $_;

    my @lines = ReadFile "$mailstore/$msg_nbr";

    foreach (@lines) {
      if (/From:\s*(.*)/) {
	my $sender = $1;

	if ($sender =~ /<(\S*)@(\S*)>/) {
	  $sender = lc ("$1\@$2");
	} elsif ($sender =~ /(\S*)@(\S*)\ /) {
	  $sender = lc ("$1\@$2");
        } elsif ($sender =~ /(\S*)@(\S*)/) {
	  $sender = lc ("$1\@$2");
	} # if

	$emails {$msg_nbr} = $sender;
      } # if
    } # foreach
  } # foreach

  verbose scalar (keys (%emails)) . " emails to process";

  return %emails;
} # GetEmailsInSpool

sub RemoveEmailInSpool ($) {
  my ($msg_nbr) = @_;

  my $datafile		= "$mailstore/${msg_nbr}-D";
  my $header_file	= "$mailstore/${msg_nbr}-H";
  my $j_file		= "$mailstore/${msg_nbr}-J";

  if (-f $datafile) {
    unlink $datafile
      or error "Unable to unlink $datafile - $!";
  } # if

  if (-f $header_file) {
    unlink $header_file
      or error "Unable to unlink $header_file - $!";
  } # if

  if (-f $j_file) {
    unlink $j_file
      or error "Unable to unlink $j_file - $!";
  } # if
} # RemoveEmailInSpool

sub FilterEmails (%) {
  my %emails= @_;

  my $removed = 0;

  foreach (sort (keys (%emails))) {
    my $msg_nbr;

    if (/(\S+)-H$/) {
      $msg_nbr = $1;
    } # if

    my $sender = $emails {"${msg_nbr}-H"};

    if ($sender eq "maps\@defaria.com" ||
	$sender eq "mailer-daemon\@defaria.com" ||
        $sender =~ /^defaria.*\@defaria.com$/) {
      verbose "Removing email $msg_nbr with sender of $sender";
      RemoveEmailInSpool $msg_nbr;
      $removed++;

#     Need to get $sender_long. Should call ReadMsg from maps. Have to
#     reorganize how this program flows...
#
#     } elsif ($sender eq $user_email and
# 	     (lc ($sender_long) !~ lc ("\"$username\" <$user_email>") and
# 	      lc ($sender_long) !~ lc ("$username <$user_email>"))) {
#       RemoveEmailInSpool $msg_nbr;
#       $removed++;
    } elsif (OnNulllist $sender) {
      verbose "Nulllist $msg_nbr ($sender)";

      Nulllist $sender;
      RemoveEmailInSpool $msg_nbr;
      $removed++;
    } # if
  } # foreach

  return $removed;
} # FilterEmails
# Main

my %opts;
my $result = GetOptions (\%opts,
                         "usage"	=> sub { Usage },
                         "verbose"	=> sub { set_verbose },
			 "debug"	=> sub { set_debug },
                        );

my $removed = FilterEmails (GetEmailsInSpool ());

verbose "$removed emails removed from the mail store";

exit;