PHP Notice: Undefined offset: 0

I have errors in WordPress:

PHP Notice: Undefined offset: 0 in
/home/userpro/public_html/wp-content/themes/hoon/inc/tweaks.php on
line 602

PHP Notice: Trying to get property of non-object in
/home/userpro/public_html/wp-content/themes/hoon/inc/tweaks.php on
line 602

Code:

/**
 * Display Future Posts
 *
 * Display future post in the events category to all users.
 */
function hoon_show_all_future_posts( $posts ) {

    global $wp_query, $wpdb;

    if ( is_single() && $wp_query->post_count == 0 ) {
        $events_cat = hoon_option( 'events_category' );
        $request = $wpdb->get_results( $wp_query->request );
        /* Line 602 bellow  */  
        if ( post_is_in_descendant_category( $events_cat, $request[0]->ID ) || in_category( $events_cat, $request[0]->ID ) ) {
            $posts = $request;
        }
    }
    return $posts;
}
add_filter( 'the_posts', 'hoon_show_all_future_posts' );