aristath/kirki

<?php
/**
 * Handles selective refreshes for Kirki fields.
 *
 * @package kirki-framework/module-selective-refresh
 * @author Ari Stathopoulos (@aristath)
 * @copyright Copyright (c) 2019, Ari Stathopoulos (@aristath)
 * @license https://opensource.org/licenses/MIT
 * @since 1.0.0
 */

namespace Kirki\Module;

/**
 * Handle selective refreshes introduced in WordPress 4.5.
 */
class Selective_Refresh {

    /**
     * An array of fields with selective refreshes.
     *
     * @static
     * @access private
     * @since 1.0.0
     * @var array
     */
    private static $fields = [];

    /**
     * Adds any necessary actions & filters.
     *
     * @access public
     */
    public function __construct() {
        add_filter( 'kirki_field_add_setting_args', [ $this, 'filter_setting_args' ], 10, 2 );
    }

    /**
     * Filter setting args.
     *
     * @access public
     * @since 1.0.0
     * @param array                $field        The field arguments.
     * @param WP_Customize_Manager $wp_customize The customizer instance.
     * @return array
     */
    public function filter_setting_args( $field, $wp_customize ) {

        // Abort if selective refresh is not available.
        if ( ! isset( $wp_customize->selective_refresh ) ) {
            return $field;
        }

        if ( isset( $field['partial_refresh'] ) && ! empty( $field['partial_refresh'] ) ) {

            // Start going through each item in the array of partial refreshes.
            foreach ( $field['partial_refresh'] as $partial_refresh => $partial_refresh_args ) {

                // If we have all we need, create the selective refresh call.
                if ( isset( $partial_refresh_args['render_callback'] ) && isset( $partial_refresh_args['selector'] ) ) {
                    $partial_refresh_args = wp_parse_args(
                        $partial_refresh_args,
                        [
                            'settings' => $field['settings'],
                        ]
                    );
                    $wp_customize->selective_refresh->add_partial( $partial_refresh, $partial_refresh_args );

                    // If partial refresh is set, change the transport to auto.
                    $field['transport'] = 'postMessage';
                }
            }
        }

        return $field;
    }
}