#!/usr/bin/perl -w

=head1 NAME 

imapsync - synchronize mailboxes between two imap servers.

$Revision: 1.7 $

=head1 INSTALL

 Get imapsync at http://www.linux-france.org/prj/imapsync/dist/
 tar xzvf  imapsync-x.xx.tgz  # x.xx is the version number
 Read the INSTALL file.
 freshmeat record: http://freshmeat.net/projects/imapsync/

=head1 SYNOPSIS

  imapsync [options]

  imapsync --help
  imapsync

  imapsync [--host1 server1]  [--port1 <num>]
           [--user1 <string>] [--passfile1 <string>] 
           [--host2 server2]  [--port2 <num>]
           [--user2 <string>] [--passfile2 <string>] 
	   [--folder <string> --folder <string> ...] 
           [--delete] [--expunge]
           [--dry]
           [--debug] [--debugimap]
           [--version] [--help]
  
=cut
# comment
=pod

=head1 DESCRIPTION

The command imapsync is a tool allowing incremental and recursive 
imap transfer from one mailbox to another.

We sometimes need to transfer mailboxes from one imap server to
another. This is called migration.

imapsync is the adequate tool because it reduces the amount of data
transfered by not transfering a given message if it is already on
both sides. All flags are preserved, unread will stay unread, read
will stay read, deleted will stay deleted. You can stop the
transfert at any time and restart it later, imapsync is adapted
to a bad connection.

You can decide to delete the messages from the source mailbox
after a successful transfert (it is a good feature when migrating).
In that case, use the --delete option, and run imapsync again
with the --expunge option.

You can also just synchronize a mailbox A from another mailbox B
in case you just want to keep a "live" copy of B in A.

=head1 OPTIONS

Invoke: imapsync --help

=head1 HISTORY

I wrote imapsync because an enterprise (basystemes) paid me to install
a new imap server without loosing huge old mailboxes located on a far 
away remote imap server accessible by a low bandwith link. The tool
imapcp (written in python)  could not help me because I had to verify
every mailbox was well
transfered and delete it after a good transfert. imapsync started its life
being a copy_folder.pl patch.
The tool copy_folder.pl comes from the Mail-IMAPClient-2.1.3 perl 
module tarball source (in the examples/ directory of the tarball).

=head1 EXAMPLES

While working on imapsync parameters please run imapsync in dry mode (no
modification induced) with the --dry option. Nothing bad can be done
this way.

To synchronize the imap account "buddy" on host "imap.src.fr" to the
imap account "max" on host "imap.dest.fr" (the passwords are located
in too files "/etc/secret1" for "buddy", "/etc/secret2" for "max") :

 imapsync --host1 imap.src.fr  --user1 buddy --passfile1 /etc/secret1 \
          --host2 imap.dest.fr --user2 max   --passfile2 /etc/secret2

Then, you will have buddy's mailbox updated from max's mailbox.

=head1 EXIT STATUS

imapsync will exit with a 0 status (return code) if everything went good.
Otherwise, it exits with a non-zero status.

So if you have a buggy internet connection, you can use this loop 
in a Bourne shell:

        while ! imapsync ...; do 
              echo imapsync not complete
        done

=head1 AUTHOR

Gilles LAMIRAL lamiral@linux-france.org

=head1 LICENSE

imapsync is free, gratis and open source software cover by the GNU General 
Public License. See the GPL file included in the distribution or the web site
http://www.gnu.org/licenses/licenses.html

=head1 BUGS

No known bug.
Report any bugs to the author: lamiral@linux-france.org

=head1 SIMILAR SOFTWARES

None known.
Feedback will be welcome.

$Id: imapsync,v 1.7 2003/03/15 03:40:54 gilles Exp gilles $

=cut


++$|;
use strict;
use Getopt::Long;
use Mail::IMAPClient;
use Digest::MD5  qw(md5_base64);


my(
	$rcs, $debug, $debugimap, $error,
	$host1, $host2, $port1, $port2,
	$user1, $user2, $password1, $password2, $passfile1, $passfile2,
	@folder,
	$delete, $expunge, $dry, 
	$version, $VERSION, $help, 
	
);

use vars qw ($opt_G); # missing code for this will be option.


$rcs = ' $Id: imapsync,v 1.7 2003/03/15 03:40:54 gilles Exp gilles $ ';
$rcs =~ m/,v (\d+\.\d+)/;
$VERSION = ($1) ? $1 : "UNKNOWN";
$error=0;

get_options();

sub missing_option {
	my ($option) = @_;
	die "$option option must be used, run $0 --help for help\n";
}

$host1 || missing_option("--host1") ;
$port1 = (defined($port1)) ? $port1 : 143;
$user1 || missing_option("--user1");
$password1 || $passfile1 || missing_option("--passfile1 or --password1");
$password1 = (defined($passfile1)) ? firstline ($passfile1) : $password1;

$host2 || missing_option("--host2") ;
$port2 = (defined($port2)) ? $port2 : 143;
$user2 || missing_option("--user2");
$password2 || $passfile2 || missing_option("--passfile2 or --password2");
$password2 = (defined($passfile2)) ? firstline ($passfile2) : $password2;

print "From imap server [$host1] port [$port1] user [$user1]\n";
print "To   imap server [$host2] port [$port2] user [$user2]\n";

my $from = ();
my $to = ();
$from = Mail::IMAPClient->new( Server   => $host1,
			       User     => $user1,
			       Password => $password1,
			       Fast_IO  => 1,
			       Uid      => 1,
			       Peek     => 1,
			       Debug    => $debugimap,) 
  or die "can't open imap connection on [$host1] with user [$user1]\n";


$to = Mail::IMAPClient->new( Server => $host2,
			     User => $user2,
			     Password=> $password2,
			     Fast_IO => 1,
			     Uid => 1,
			     Peek => 1,
			     Debug => 0,) 
  or die "can't open imap connection on [$host2] with user [$user2]\n";

my @f_folders = (scalar(@folder)) ? @folder : @{$from->folders()};

FOLDER: foreach my $f_fold (@f_folders) {
	my $t_fold;
	print "From Folder $f_fold\n";
	unless ($f_fold =~ m/^INBOX/) {
		$t_fold = "INBOX." . $f_fold;
	}else {
		$t_fold = $f_fold;
	}
	$t_fold =~ s@\\@\.@g;
	$t_fold =~ s@\/@\.@g;
	unless ($from->select($f_fold)) {
		warn 
		"From Folder $f_fold : Could not select ",
		$from->LastError,  "\n";
		$error++;
		next FOLDER;
	}
	unless ($to->exists($t_fold)) { 
		print "To   Folder $t_fold does not exist\n";
		print "Creating folder $t_fold\n";
		unless ($dry){
			unless ($to->create($t_fold)){
				warn "Couldn't create $t_fold ",
				$to->LastError,"\n";
				$error++;
				next FOLDER;
			}
		}else{
			next FOLDER;
		}
	}
    
	unless ($to->select($t_fold)) { 
		warn 
		"To   Folder $t_fold : Could not select ",
		$to->LastError, "\n";
		$error++;
		next FOLDER;
	}

	if ($expunge){
		print "Expunging $f_fold and $t_fold\n";
		$from->expunge();
		$to->expunge();
	}

	my @f_msgs = $from->search("ALL");
	$debug and print "LIST FROM : @f_msgs\n";
	my @t_msgs = $to->search("ALL");
	$debug and print "LIST TO   : @t_msgs\n";

	my %f_hash = ();
	my %t_hash = ();

sub header_parse {
	# @msgs_all;
	# %hash;

}
    
	$debug and print "From Parse\n";
	foreach my $m (@f_msgs) {
		$debug and print "-" x 50, "\nMSG $m\n";
		my $head = $from->parse_headers($m,"ALL");
		my $headstr;
		$debug and print "Head NUM:", scalar(keys(%$head)), "\n";
        	next unless(scalar(keys(%$head)));	    
		foreach my $h (sort keys(%$head)){
			my $val = $head->{$h}[0];
			# no accent in headers !
			$val =~ y//XXXX/;
			$debug and print "H $h:", $val, "\n";
			$headstr .= "$h:". $val;
		}
		my $m_md5 = md5_base64($headstr);
		my $size = $from->size($m);
		$debug and print "From $m:$m_md5:$size\n";

		$f_hash{"$m_md5:$size"}{'5'} = "$m_md5:$size";
		$f_hash{"$m_md5:$size"}{'s'} = $size;
		$f_hash{"$m_md5:$size"}{'m'} = $m;
	}
    
	$debug and print "To   Parse\n";
	foreach my $m (@t_msgs) {
		$debug and print "-" x 50, "\nMSG $m\n";
		my $head = $to->parse_headers($m,"ALL");
        	my $headstr;
		$debug and print "Head NUM:", scalar(keys(%$head)), "\n";
		next unless(scalar(keys(%$head)));
		foreach my $h (sort keys(%$head)){
            		$debug and print "$h:", $head->{$h}[0], "\n";
            		$headstr .= "$h:".$head->{$h}[0];
        	}
        	my $m_md5 = md5_base64($headstr);
		my $size = $to->size($m);
		$debug and print "To   $m:$m_md5:$size\n";
		$t_hash{"$m_md5:$size"}{'5'} = "$m_md5:$size";
        	$t_hash{"$m_md5:$size"}{'s'} = $size;
        	$t_hash{"$m_md5:$size"}{'m'} = $m;
	}
	$debug and print "Verifying\n";
	# messages in "from" that are not good in "to"
    
	MESS: foreach my $m_id (keys(%f_hash)) {
		my $f_size = $f_hash{$m_id}{'s'};
		my $f_msg = $f_hash{$m_id}{'m'};
		$debug and print "key     $m_id #$f_msg\n";
		unless (exists($t_hash{$m_id})) {
			print "Message NO msg #$f_msg $m_id in $t_fold\n";
			# copy
			print "Copying msg #$f_msg:$f_size to folder $t_fold\n";
			unless ($dry) {
				my $string = $from->message_string($f_msg);
				#$opt_y and print $string;
				my $new_id;
				unless($new_id = $to->append($t_fold,$string)){
					warn "Couldn't append msg #$f_msg to folder $t_fold",
					$to->LastError, "\n";
					$error++;
					next MESS;
				}else{
				# good
					print "Copied msg #$f_msg to folder $t_fold msg #$new_id\n";
					$to->store($new_id,
						"+FLAGS (" . join(" ",
						@{$from->flags($f_msg)}
					 	) . ")");
				}
			}
	    		next MESS;
		}else{
			$debug and print "Message $m_id found in t:$t_fold\n";
		}
		#$debug and print "MESSAGE $m_id\n"; 
		my $t_size = $t_hash{$m_id}{'s'};
		my $t_msg  = $t_hash{$m_id}{'m'};
		unless ($f_size == $t_size) {
			print 
			"Message $m_id SZ_BAD  f:$f_msg:$f_size t:$t_msg:$t_size\n";
			# delete in to and recopy ?
			# NO recopy CODE HERE. to be written if needed.
			$error++;
			if ($opt_G){
				print "Deleting msg f:#$t_msg in folder $t_fold\n";
				$to->delete_message($t_msg);
			}
		}else {
	    		# Good 
			$debug and print
			"Message $m_id SZ_GOOD f:$f_msg:$f_size t:$t_msg:$t_size\n";
			if($delete) {
				print "Deleting msg #$f_msg in folder $f_fold\n";
				$from->delete_message($f_msg);
			}
		}
	}
}

stats();

exit(1) if($error);

sub stats {
	print "Detected $error errors\n";

}


sub get_options
{
	my $numopt = scalar(@ARGV);
        my $opt_ret = GetOptions(
                                   "debug"       => \$debug,
                                   "debugimap"   => \$debugimap,
                                   "host1=s"     => \$host1,
                                   "host2=s"     => \$host2,
                                   "port1=i"     => \$port1,
                                   "port2=i"     => \$port2,
                                   "user1=s"     => \$user1,
                                   "user2=s"     => \$user2,
                                   "password1=s" => \$password1,
                                   "password2=s" => \$password2,
                                   "passfile1=s" => \$passfile1,
                                   "passfile2=s" => \$passfile2,
				   "folder=s"    => \@folder,
                                   "delete!"     => \$delete,
                                   "dry!"        => \$dry,
                                   "expunge!"    => \$expunge,
                                   "version"     => \$version,
                                   "help"        => \$help,
                                  );
          
        $debug and print "get options: [$opt_ret]\n";
        print "$VERSION\n" and exit if ($version) ;
        usage() and exit if ($help or ! $numopt) ;
        exit unless ($opt_ret) ;
	
	
}


sub  firstline {
        # extract the first line of a file (without \n)

        my($file) = @_;
        my $line  = "";
        
        open FILE, $file or die("$! $file");
        chomp($line = <FILE>);
        close FILE;
        $line = ($line) ? $line : "!EMPTY! $file";
        return $line;   
}

sub usage {
        print <<EOF;

usage: $0 [options]

Several options are mandatory. 

--host1       <string> : "from" imap server. Mandatory.
--port1       <int>    : port to connect. Default is 143.
--user1       <string> : user to login.   Mandatory.
--password1   <string> : password for the user1. Dangerous, use --passfile1
--passfile1   <string> : password file for the user1. Contains the password.
--host2       <string> : "destination" imap server. Mandatory.
--port2       <int>    : port to connect. Default is 143.
--user2       <string> : user to login.   Mandatory.
--password2   <string> : password for the user2. Dangerous, use --passfile2
--passfile2   <string> : password file for the user2. Contains the password.
--folder      <string> : sync only this folder
--folder      <string> : and this one.
--folder      <string> : and this one, etc.
--delete               : delete messages in "from" imap server after
                         a successful transfert. useful in case you
                         want to migrate from one server to another one.
			 With imap, delete tags messages as deleted, they
			 are not really deleted. See expunge.
--expunge              : expunge messages on both account.
                         expunge delete messages marked deleted.
--dry                  : do nothing, just print what would be done.
--debug                : debug mode.
--debugimap            : imap debug mode.
--version              : print sotfware version.
--help                 : print this.

Example: to synchronise imap account "foo" on "imap.truc.org"
                     to imap account "bar" on "imap.trac.org"

$0 \\
   --host1 imap.troc.org --user1 foo --passfile1 /etc/secret1 \\
   --host2 imap.trac.org --user2 bar --passfile2 /etc/secret2


$rcs
      imapsync copyleft is the GNU General Public License.
EOF
}
