regex code to call the images into a slide (MyBB) - regex

Question

does anyone here familiar with MyBB?
I want to display all images in a thread in the forums that I have chosen previously in a gallery slide.
[img]*URL_IMAGE_FILE*[/img]
of the slider is a slider that I mean the following.
http://community.mybb.com/attachment.php?aid=26307
that where: 17 and 18 there are IDs that I choose.
WHERE t.fid IN (17,18) AND t.visible='1' AND t.closed NOT LIKE 'moved|%' AND t.firstpost=p.pid
please correct the following code if there is an error.
// Slider Images
/***** Slider Gallery Thread End *****/
/* LATEST THREADS */
$query = $db->query("
SELECT t.*, p.message, a.aid, a.thumbnail
FROM ".TABLE_PREFIX."threads t
LEFT JOIN ".TABLE_PREFIX."posts p ON (p.pid = t.firstpost)
LEFT JOIN ".TABLE_PREFIX."attachments a ON(a.pid=p.pid)
WHERE t.fid IN (17,18) AND t.visible='1' AND t.closed NOT LIKE 'moved|%' AND t.firstpost=p.pid
ORDER BY t.dateline DESC
LIMIT 1");
if(!$db->num_rows($query))
{
// Needs to output a nice "no posts here" box
$title = 'Error';
$message = 'No Message';
eval("\$tricks = \"".$templates->get("member_profile_no_content")."\";");
}
else
{
// Set up the parser options.
$parser_options = array(
"allow_html" => $forum['allowhtml'],
"allow_mycode" => $forum['allowmycode'],
"allow_smilies" => $forum['allowsmilies'],
"allow_imgcode" => $forum['allowimgcode'],
"allow_videocode" => $forum['allowvideocode'],
"filter_badwords" => 1
);
while($threads = $db->fetch_array($query))
{
$threads['threadlink'] = get_thread_link($threads['tid']);
if($threads['lastposteruid'] == 0)
{
$lastposterlink = $threads['lastposter'];
}
else
{
$lastposterlink = build_profile_link($threads['lastposter'], $threads['lastposteruid']);
}
$view_string = 'Views';
$reply_string = 'Replies';
if($threads['views'] == 1)
{
$view_string = 'Views';
}
if($threads['replies'] == 1)
{
$reply_string = 'Replies';
}
if ($thread['thumbnail'])
{
$thumbnail = '';
}
else
{
$thumbnail = '';
}
$threads['profilelink'] = build_profile_link($threads['username'], $threads['uid']);
$threads['reply'] = $lang->sprintf($lang->thread_views_stats, my_number_format($threads['replies']), $reply_string, my_number_format($threads['views']), $view_string);
$threads['date'] = my_date($mybb->settings['dateformat'], $threads['dateline']);
$threads['time'] = my_date($mybb->settings['timeformat'], $threads['dateline']);
$threads['lastpostlink'] = get_thread_link($threads['tid'], 0, "lastpost");
$threads['message'] = my_substr($threads['message'], 0, 150) . "...";
$threads['message'] = $parser->parse_message($threads['message'], $options);
eval("\$tricks .= \"".$templates->get("depan_slides")."\";");
}
}
/***** Slider Gallery Thread End *****/