woo-custom-order-status/custom-order-status-for-woocommerce.php

<?php
/**
 * Plugin Name: Custom Order Status for WooCommerce
 * Description: Adds the ability to create and manage custom order statuses in WooCommerce.
 * Plugin URI: https://absoftlab.com
 * Version: 1.0.2
 * Author: absoftlab
 * Author URI: https://absoftlab.com
 * License: GPL2
 */

if (!defined('ABSPATH')) exit;

class Absoftlab_Custom_Order_Status_Manager {
    private $option_key = 'absoftlab_custom_order_statuses';

    public function __construct() {
        add_action('admin_menu', [$this, 'add_admin_menu']);
        add_action('admin_init', [$this, 'handle_form_submit']);
        add_action('init', [$this, 'register_custom_statuses']);
        add_filter('wc_order_statuses', [$this, 'add_to_wc_statuses']);
    }

    // Admin Menu
    public function add_admin_menu() {
        add_submenu_page(
            'woocommerce',
            'Custom Order Status',
            'Custom Order Status',
            'manage_woocommerce',
            'absoftlab-order-status',
            [$this, 'settings_page']
        );
    }

    // Get stored statuses
    private function get_statuses() {
        return get_option($this->option_key, []);
    }

    // Register statuses with WooCommerce
    public function register_custom_statuses() {
        foreach ($this->get_statuses() as $slug => $label) {
            register_post_status($slug, [
                'label'                     => $label,
                'public'                    => true,
                'exclude_from_search'       => false,
                'show_in_admin_all_list'    => true,
                'show_in_admin_status_list' => true,
                'label_count'               => _n_noop("$label (%s)", "$label (%s)")
            ]);
        }
    }

    // Add to WooCommerce list
    public function add_to_wc_statuses($statuses) {
        foreach ($this->get_statuses() as $slug => $label) {
            $statuses[$slug] = $label;
        }
        return $statuses;
    }

    // Handle form: add/delete
    public function handle_form_submit() {
        if (!current_user_can('manage_woocommerce')) return;

        // Add new status
        if (isset($_POST['absoftlab_add_status'])) {
            check_admin_referer('absoftlab_add_status');
            $label = sanitize_text_field($_POST['status_label']);
            $slug = 'wc-' . sanitize_title($label);

            $statuses = $this->get_statuses();
            $statuses[$slug] = $label;
            update_option($this->option_key, $statuses);
            wp_redirect(admin_url('admin.php?page=absoftlab-order-status&added=1'));
            exit;
        }

        // Delete status
        if (isset($_GET['absoftlab_delete']) && isset($_GET['_wpnonce'])) {
            if (wp_verify_nonce($_GET['_wpnonce'], 'absoftlab_delete_status')) {
                $slug = sanitize_text_field($_GET['absoftlab_delete']);
                $statuses = $this->get_statuses();
                unset($statuses[$slug]);
                update_option($this->option_key, $statuses);
                wp_redirect(admin_url('admin.php?page=absoftlab-order-status&deleted=1'));
                exit;
            }
        }
    }

    // Admin Page HTML
    public function settings_page() {
        $statuses = $this->get_statuses();
        ?>
        <div class="wrap">
            <h1>Custom Order Status Manager</h1>

            <?php if (isset($_GET['added'])): ?>
                <div class="notice notice-success"><p>Status added successfully!</p></div>
            <?php elseif (isset($_GET['deleted'])): ?>
                <div class="notice notice-success"><p>Status deleted successfully!</p></div>
            <?php endif; ?>

            <h2>Add New Status</h2>
            <form method="post">
                <?php wp_nonce_field('absoftlab_add_status'); ?>
                <table class="form-table">
                    <tr>
                        <th><label for="status_label">Status Label</label></th>
                        <td><input type="text" name="status_label" id="status_label" required /></td>
                    </tr>
                </table>
                <p><input type="submit" name="absoftlab_add_status" class="button button-primary" value="Add Status" /></p>
            </form>

            <h2>Existing Statuses</h2>
            <table class="widefat striped">
                <thead><tr><th>Slug</th><th>Label</th><th>Action</th></tr></thead>
                <tbody>
                <?php foreach ($statuses as $slug => $label): ?>
                    <tr>
                        <td><?php echo esc_html($slug); ?></td>
                        <td><?php echo esc_html($label); ?></td>
                        <td>
                            <a href="<?php echo wp_nonce_url(admin_url('admin.php?page=absoftlab-order-status&absoftlab_delete=' . $slug), 'absoftlab_delete_status'); ?>"
                            class="button button-small delete">Delete</a>
                        </td>
                    </tr>
                <?php endforeach; ?>
                </tbody>
            </table>
        </div>
        <?php
    }
}

new Absoftlab_Custom_Order_Status_Manager();