#!/usr/bin/perl

# This is intended to accept email from procmail as a filter
#
# It takes any attached jpg files, converts them to gifs and then
# turns them into a single animated gif.
# The email is then passed back to procmail after the jpgs have been
# dettached and the animated gif has been attached.

# in addition to the MIME modules indicated below, it requires
# these two external programs:

# whirlgif: http://www.msg.net/utility/whirlgif/
# and
# djpeg: http://freshmeat.net/projects/libjpeg/?topic_id=105%2C809

# example procmailrc snippet:
# :0
# * ^TOanimblogpost
# {
#   # filter to create animated gif
#   # f = filter
#   # h = filter the header
#   # b = filter the body too
#   :0fhb
#   |/home/dav/bin/anim_gif_filter.pl
# 
#   # post this to my blog
#   :0 c
#   |/home/dav/bin/blogpost.pl -c/home/dav/.blogpostrc.akuaku
# }

#use strict;

use POSIX;
use MIME::Explode;
use MIME::Entity;

my $pid = $$;
my $datestring = strftime('%Y-%m-%d_%H%M%S', localtime);

my $home_dir = $ENV{'HOME'};

my $work_dir = '$home_dir/tmp_anim';
my $unique_name = "${datestring}_${pid}";
my $anim_gif_file = "$unique_name_anim.gif";
my $anim_gif_path = "$work_dir/$anim_gif_file";
my $temp_mail = "$work_dir/$unique_name.mail";

my $from;
my $to;
my $subject;
my @attachments;

exit;

# first parse STDIN for header info, and store in a temp 
# file so it can be exploded later
open( TMPMAIL, ">$temp_mail") or exit;
while (<STDIN>) {
   if ($from == undef && $_ =~ /^From: (.+)/) {
      $from = $1;
   }
   if ($to == undef && $_ =~ /^To: (.+)/) {
      $to = $1;
   }
   if ($subject == undef && $_ =~ /^Subject: (.+)/) {
      $subject = $1;
   }
   print TMPMAIL;
}
close TMPMAIL;

# reopen in read mode so we can explode it
open( TMPMAIL, $temp_mail );
my $explode = MIME::Explode->new(
      output_dir          => $work_dir,
      mkdir               => 0755,
      decode_subject      => 1,
      chcek_content_type  => 1,
      exclude_types       => [],
    );
#my $headers = $explode->parse(\*STDIN, \*TMPOUT);
#my $headers = $explode->parse(\*STDIN);
my $headers = $explode->parse(\*TMPMAIL);
close TMPMAIL;

# parse out the headers
my $mail = &parseMail;
my $body = $mail->{body};
  
# set whirlgif options from message body
my $loop = '-loop';      #default to loop forever
my $delay = '-time 50';  #default to half a second
  
if ($body =~ m/noloop/) {
     $body =~ s/noloop//;
     $loop = '';
}
  
if ($body =~ m/delay(\d+)/) {
     my $hundrenths = $1;
     $body =~ s/delay$hundrenths//;
     $delay = "-time $hundrenths";
}

# do the actual jpeg->animated gif conversions
&processAttachments;

### Create the top-level, and set up the mail headers:
$top = MIME::Entity->build(Type    =>"multipart/mixed",
                           From    => $from,
                           To      => $to,
                           Subject => $subject);

$top->attach(Data => $body);

# attach the gif
foreach $attachment (@attachments) {
  if ($attachment =~ /\.gif$/) {
     $top->attach(
               Path        => "$work_dir/$attachment",
               Type        => "image/gif",
               Encoding    => "base64");
    # ignore other attachments fo rnow
  }
}

# now dump it back out, since this is a procmail filter
$top->print(\*STDOUT);


### clean up
unlink $temp_mail;
unlink "$work_dir/file.txt";  # this needs to be fixed, might delete wrong

foreach $attachment (@attachments) {
   unlink "$work_dir/$attachment";
}


#########################################################################

sub processAttachments {

  my @gifs;
  #my @jpg_to_remove;
  
  # rename images making them unique
  for ($count = 0; $count<=$#attachments; $count++) {
     $attachments[$count]=~s/;//g; # security precaution
     #print "ATT: $attachments[$count]\n";
     $oldpath = "$work_dir/$attachments[$count]";
     if ($oldpath =~ /\.([Jj][Pp][Ee]?[Gg])$/) {
        $newname = "${datestring}_${pid}_${count}.jpg";
        $newpath = "$work_dir/$newname";
        rename( $oldpath, $newpath ) && ($attachments[$count]=$newname);
        $tempgif = "$work_dir/${datestring}_${pid}_${count}.gif";
        my $conv_cmd = "djpeg -gif $newpath > $tempgif";
        #print "*** $conv_cmd\n";
        system( $conv_cmd );
        unshift( @gifs, $tempgif );
        #unshift( @jpg_to_remove, $attachments[$count] );
     } else {
        $attachments[$count]=$newname;
     }
  }
  
  my $anim_gif_file = "${datestring}_${pid}_anim.gif";
  my $anim_gif_path = "$work_dir/$anim_gif_file";
  
  my $animate_cmd = "whirlgif $loop $delay -o $work_dir/$anim_gif_file ";
  foreach $gif (@gifs) {
     $animate_cmd = $animate_cmd . $gif . " ";
  }
  $animate_cmd = $animate_cmd . " 2>&1 >/dev/null";
  #print "*** $animate_cmd\n";
  my $devnull = `$animate_cmd`;
  
  # clean up
  foreach $gif (@gifs) {
     unlink "$gif";
  }

  unshift( @attachments, $anim_gif_file );

}

sub parseMail {
   my $body;
   my $subject;
   my $dateline;
   my $jpgs=0;

 for my $part (sort{ $a cmp $b } keys(%{$headers})) {
  my $filename = $headers->{$part}->{'content-disposition'}->{filename};
  my $filepath = $headers->{$part}->{'content-disposition'}->{filepath};
  #print "GOT: $filename\n";
  if ($filename eq 'file.txt') {
    $body = `cat $work_dir/$filename`;
    chop $body;
  } elsif ($filename =~ m/[Jj][Pp][Ee]?[Gg]$/) {
    #print "ADD: $filename\n";
    $attachments[$jpgs++]=$filename;
    $attachments_full[$jpgs]=$filepath;
    chmod 0644, $filepath;
    #print "filename: $filename\n";
    #print "filepath: $filepath\n";
  }
 }
 $dateline = $headers->{'0.0'}->{date};
 $subject =  join("", @{$headers->{'0.0'}->{subject}->{value}});
 my $mail = {
      body => $body,
      dateline => $dateline,
      subject => $subject
    };
 return $mail;
}

#########################################################################