<?php

/*

        Script variables

*/

$target_connectionstring = "{mail.service.com:993/imap/ssl/novalidate-cert}";
$target_username = "user1";
$target_password = "password1";
$target_folder = 'migration';

$source_connectionstring = "{mail.server.com:143/imap/notls}INBOX";
$source_username = "user2";
$source_password = "password2";

$migratedfolders = array();

/*

        Functions

*/

/* Write log to the filesystem */
function errorlog($message){

        $data = "[" . date("F j, Y, g:i a") . "]\t" . $message . "\n\n";
        file_put_contents('/tmp/imap_migration_log', $data, FILE_APPEND);

}

/* Keep track on processed folders */
function migratedfolders($folder){

        file_put_contents('/tmp/imap_migration_history', $folder . "\n", FILE_APPEND);

}


/*

        Start the job

*/

/* Get the complete list of all source folders */
$source_imap = imap_open($source_connectionstring, $source_username, $source_password, "", 10)
or die("can't connect: " . imap_last_error());

$folders = imap_list($source_imap, $source_connectionstring, "*");

imap_close($source_imap);

if ($folders !== false) {

        foreach ($folders as $value) {

                /* Remove connection info in the path */
                $folderpath = str_replace($source_connectionstring, "", $value);

                /* Check if the folder already are completely migrated */
                if(is_file('/tmp/imap_migration_history')){
                        $migratedfolders = explode("\n", file_get_contents('/tmp/imap_migration_history'));
                }

                if(!in_array($folderpath, $migratedfolders)){

                        /* Output info */
                        print "\n\n\nWorking on $folderpath/\n";

                        /* Remove the folder name and keep the path     */
                        $targetpath = explode("/", $folderpath);
                        array_pop($targetpath);
                        $targetroot = mb_convert_encoding(implode("/", $targetpath), "UTF7-IMAP","ISO-8859-1");

                        /* Connect to the server */
                        $target_imap = imap_open($target_connectionstring . $target_folder . $targetroot, $target_username, $target_password, "", 10)
                        or die("can't connect: " . imap_last_error());

                        /* Create folder */
                        if(!imap_createmailbox($target_imap, mb_convert_encoding($target_connectionstring . $target_folder . $folderpath, "UTF7-IMAP","ISO-8859-1") . '/')){

                                errorlog("Error creating the targetfolder $folderpath");

                        }

                        /* Disconnect */
                        imap_close($target_imap);

                        /* Connect to the servers */
                        $target_imap = imap_open(mb_convert_encoding($target_connectionstring . $target_folder . $folderpath, "UTF7-IMAP","ISO-8859-1"), $target_username, $target_password, "", 10)
                        or die("can't connect: " . imap_last_error());

                        $source_imap = imap_open($source_connectionstring . $folderpath, $source_username, $source_password, "", 10)
                        or die("can't connect: " . imap_last_error());

                        /* Get information about the source mailbox */
                        $MC = imap_check($source_imap);

                        print "$MC->Nmsgs mails to migrate:";

                        /* Fetch messages from source mailbox */
                        $result = imap_fetch_overview($source_imap,"1:{$MC->Nmsgs}",0);

                        foreach ($result as $overview) {
                                $message = imap_fetchheader($source_imap, $overview->msgno) . imap_body($source_imap, $overview->msgno);

                                /* Write message to target mailbox */
                                if(!imap_append($target_imap,mb_convert_encoding($target_connectionstring . $target_folder . $folderpath, "UTF7-IMAP","ISO-8859-1"),$message,"\\Seen")){

                                        /* Log errors */
                                        errorlog("Coundn't migrate the email \"$overview->subject\" from $overview->date in the $folderpath");

                                        /* Output info */
                                        print "|";
                                }
                                else{
                                        /* Output info */
                                        print ".";
                                }

                        }

                        /* Fetch messages from source mailbox */
                        imap_close($source_imap);
                        imap_close($target_imap);

                        /* Write to the history that we are finished with the folder */
                        migratedfolders($folderpath);
                }
        }

        /* Delete history file */
        unlink('/tmp/imap_migration_history');

}
else{
        print "Couldn't get source IMAP trees!";
}

?>