<?php
add_filter( 'rwmb_meta_boxes', function ( $meta_boxes ) {
    $prefix       = '';
    $meta_boxes[] = array(
        'id'     => 'finite_scroll',
        'title'  => __( 'Finite Scroll' ),
//      'post_types' => array( 'recipe' ),
        'fields' => array(
            array(
                'id'         => $prefix . 'related_recipe',
                'type'       => 'group',
                'clone'      => true,
                'sort_clone' => true,
                'fields'     => array(
                    array(
                        'name'       => __( 'Related Recipe:' ),
                        'id'         => $prefix . 'rel_recipe',
                        'type'       => 'select_advanced',
                        'options'    => prefix_get_selected_post(),
                        'js_options' => array(
                            'ajax'               => array(
                                'url'      => '/wp-admin/admin-ajax.php?action=select_advanced_post_lookup&post_type=post',
                                'dataType' => 'json',
                                'type'     => 'get',
                                'delay'    => '250',
                            ),
                            'minimumInputLength' => 3,
                            'allowClear'         => true,
                            'placeholder'        => 'Select recipe',
                        ),
                    ),
                ),
            ),
        ),
    );

    return $meta_boxes;
} );

add_action( 'wp_ajax_select_advanced_post_lookup', 'select_advanced_post_lookup' );
function select_advanced_post_lookup() {
    global $wpdb;
    $post_types = "'" . implode( "','", explode( ',', $_GET['post_type'] ) ) . "'";
    $keyword    = "%" . $wpdb->esc_like( $_GET['q'] ) . "%";

    $sql      = "SELECT ID, post_title" .
                " FROM $wpdb->posts" .
                " WHERE post_title LIKE '" . $keyword . "'" .
                " AND post_type IN (" . $post_types . ")" .
                " AND post_status='publish' " .
                " ORDER BY post_title LIMIT 0,15;";
    $results  = $wpdb->get_results( $sql );
    $response = array(
        'results' => array(),
    );
    foreach ( $results as $result ) {
        $response['results'][] = array( 'id' => $result->ID, 'text' => $result->post_title );
    }
    wp_send_json( $response );
}


/**
 * Get current object ID.
 *
 * @return int
 */
function prefix_get_current_post_id() {
    $post_id = filter_input( INPUT_GET, 'post', FILTER_SANITIZE_NUMBER_INT );
    if ( ! $post_id ) {
        $post_id = filter_input( INPUT_POST, 'post_ID', FILTER_SANITIZE_NUMBER_INT );
    }

    return is_numeric( $post_id ) ? absint( $post_id ) : false;
}

function prefix_get_selected_post() {
    $default = array( '' => '' );
    $post_id = prefix_get_current_post_id();
    if ( ! $post_id ) {
        return $default;
    }
    $group = get_post_meta( $post_id, 'related_recipe', true );
    if ( empty( $group ) ) {
        return $default;
    }
    $options = array();
    foreach ( $group as $clone ) {
        if ( ! isset( $clone['rel_recipe'] ) ) {
            continue;
        }
        $id             = $clone['rel_recipe'];
        $options[ $id ] = get_the_title( $id );
    }

    return $options ? $options : $default;
}