ACF Menu Depth Rule

AcfMenuDepth.php

<?php

declare(strict_types=1);

use WP_Screen;

/**
 * Class MenuDepth
 *
 * This class is used to define a custom rule for Advanced Custom Fields (ACF) plugin.
 * The rule is based on the depth of a menu item in a WordPress menu.
 *
 * @package App\Plugins\AdvancedCustomFields\Rules
 */
class AcfMenuDepth
{
    /**
     * MenuDepth constructor.
     *
     * The constructor adds the custom rule to ACF's rule types, rule values, and rule match filters.
     */
    public function __construct()
    {
        add_filter('acf/location/rule_types', [$this, 'getRuleTypes']);
        add_filter('acf/location/rule_values/menu_level', [$this, 'getRuleValues']);
        add_filter('acf/location/rule_match/menu_level', [$this, 'getRuleMatch'], 10, 3);
    }

    /**
     * Get rule types.
     *
     * This method adds the custom rule to ACF's rule types.
     *
     * @param array $choices Existing rule types.
     * @return array Modified rule types.
     */
    public function getRuleTypes(array $choices): array
    {
        $choices['Menu']['menu_level'] = __('Menu Depth', 'sage');
        return $choices;
    }

    /**
     * Get rule values.
     *
     * This method defines the possible values for the custom rule.
     *
     * @param array $choices Existing rule values.
     * @return array Modified rule values.
     */
    public function getRuleValues(array $choices): array
    {
        return range(0, 9);
    }

    /**
     * Get rule match.
     *
     * This method checks if the custom rule matches the current context.
     *
     * @param bool  $match
     * @param array $rule
     * @param array $options
     * @return bool
     */
    public function getRuleMatch(bool $match, array $rule, array $options): bool
    {
        $current_screen = get_current_screen();
        if (
            ! $current_screen instanceof WP_Screen
            || 'nav-menus' !== $current_screen->base
            || '==' !== $rule['operator']
        ) {
            return $match;
        }

        return $options['nav_menu_item_depth'] === (int) $rule['value'];
    }
}