/**
 * Limit max menu depth in admin panel 
 */

function limit_admin_menu_depth($hook)
{
    if ($hook != \'nav-menus.php\') return;

    wp_register_script(\'limit-admin-menu-depth\', get_stylesheet_directory_uri() . \'/js/admin/limit-menu-depth.js\', array(), \'1.0.0\', true);
    wp_localize_script(
        \'limit-admin-menu-depth\',
        \'myMenuDepths\',
        array(
            \'primary\' => 1, // <-- Set your menu location and max depth here
            \'footer\' => 0 // <-- Add as many as you like
        )
    );
    wp_enqueue_script(\'limit-admin-menu-depth\');
}
add_action( \'admin_enqueue_scripts\', \'limit_admin_menu_depth\' );

/**
 * Limit max menu depth in admin panel
 * Expects wp_localize_script to have set an object of menu locations
 * in the shape of { location: maxDepth, location2: maxDepth2 }
 * e.g var menu-depths = {"primary":"1","footer":"0"};
 */
(function ($) {
    // Get initial maximum menu depth, so that we may restore to it later.
    var initialMaxDepth = wpNavMenu.options.globalMaxDepth;

    function setMaxDepth() {
        // Loop through each of the menu locations
        $.each(myMenuDepths, function (location, maxDepth) {
            if (
                $(\'#locations-\' + location).prop(\'checked\') &&
                maxDepth < wpNavMenu.options.globalMaxDepth
            ) {
                // If this menu location is checked
                // and if the max depth for this location is less than the current globalMaxDepth
                // Then set globalMaxDepth to the max depth for this location
                wpNavMenu.options.globalMaxDepth = maxDepth;
            }
        });
    }

    // Run the function once on document ready
    setMaxDepth();

    // Re-run the function if the menu location checkboxes are changed
    $(\'.menu-theme-locations input\').on(\'change\', function () {
        wpNavMenu.options.globalMaxDepth = initialMaxDepth;
        setMaxDepth();
    });
})(jQuery);