Immediate duplicate post with associated meta

Hello !

I’m trying to duplicate a post as soon as it is posted with a different post_type and with all the meta associated to the initial post.

Here is the hook that I’m using :

add_action( ‘save_post’, ‘save_post_create_duplicate’,10,2 );

Here is the code for the save_post_create_duplicate function :

function save_post_create_duplicate($post_id) {
	global $wpdb;
	$post = get_post( $post_id );
	if ($post->post_type != 'specific_type') return;

	$new_post = array(
	'menu_order' => $post->menu_order,
	'comment_status' => $post->comment_status,
	'ping_status' => $post->ping_status,
	'post_author' => $post->post_author,
	'post_content' => $post->post_content,
	'post_excerpt' => $post->post_excerpt,
	'post_mime_type' => $post->post_mime_type,
	'post_parent' => $post->post_parent,
	'post_password' => $post->post_password,
	'post_status' => 'publish',
	'post_title' => $post->post_title,
	'post_type' => 'another_post_type',
	'post_name' => $post->post_name
	);

	$new_post['post_date'] = $new_post_date =  $post->post_date ;
	$new_post['post_date_gmt'] = get_gmt_from_date($new_post_date);
        //unhook function to avoid infinite loop
	remove_action('save_post', 'save_post_create_duplicate');
	$new_post_id = wp_insert_post($new_post);
        /rehook the function
	add_action('save_post', 'save_post_create_duplicate',10,2);

}

And here is the code for the other function that is supposed to duplicate the metas from the initial post to the duplicate one :

function save_post_meta_duplicate_post($new_id,$old_id, $post) {
	$post_meta_keys = get_post_custom_keys($old_id);
	if (empty($post_meta_keys))
	{
	return;
	}

	foreach ($post_meta_keys as $meta_key) {
		$meta_values = get_post_custom_values($meta_key, $old_id);
		foreach ($meta_values as $meta_value) {
			$meta_value = maybe_unserialize($meta_value);
			add_post_meta($new_id, $meta_key, $meta_value);
		}
	}
}

And the call to this function is made just after the
$new_post_id = wp_insert_post($new_post);

with this code :
save_post_meta_duplicate_post($new_post_id,$post_id,get_post($new_post_id ));

Now the issue is that the metas are empty for the first post !
I don’t understand why… Is the hook to save_post wrong ?

WordPress documentation says that the save_post action runs after the data is saved to the database. So, for me, the metas should already be there when I’m trying to get them.

Thanks a lot for your advices !