Permit to close a Woocommerce store, enabling the use of a message to warn users.

woo-close-store.php

<?php
/*
Plugin Name: 	Woo Close Store
Plugin URI:  	https://github.com/gabriserra/woo-close-store
Description: 	Woo Close Store handle store closing phase.
Version:     	0.1
Author:      	Gabriele Serra
Author URI:  	https://gabripr0.altervista.org
Text Domain: 	woo-close-store
License:     	MIT
License URI:    https://www.linux.it/scegli-una-licenza/licenses/mit/
*/

/**
 * A cutted version of Woo Store Vacation by Mahdi Yazdani
 * @see https://wordpress.org/plugins/woo-store-vacation/
 */


/**
 * Close Store Class
 *
 * Handle Woocommerce stuff
 *
 */

defined( 'ABSPATH' ) || exit;

class Woo_Close_Store {

    /**
     * Bootstraps the class and hooks required actions & filters.
     */
    public static function init() {        
        add_action('admin_notices',  __CLASS__ . '::is_woocommerce_present' , 10);
        add_action('admin_menu',  __CLASS__ . '::add_woosubmenu_page' , 99);
        add_action('admin_init',  __CLASS__ . '::register_settings' , 10);
        add_action('init',  __CLASS__ . '::closed_store', 10);
    }

    /**
     * Check if WooCommerce plugin is installed
     */
    public static function is_woocommerce_present() {
        if (!in_array('woocommerce/woocommerce.php', apply_filters('active_plugins', get_option('active_plugins'))))
            printf('<div class="notice notice-error is-dismissible"><p>%s</p></div>', esc_html__('Woocommerce non è attivo!', 'woo-close-store'));
    }

    /**
     * Create options and page under Woocommerce menu 
     */
    public static function add_woosubmenu_page() {
        add_submenu_page( 'woocommerce', 'Woo Close Store', 'Chiudi negozio', 'manage_woocommerce', 'woo-close-store', __CLASS__ . '::render_woosubmenu_page');
    }

    /**
     * Register plugin settings
     */
    public static function register_settings() {
        register_setting('woo_close_store_settings_fields', 'woo_close_store_options',  __CLASS__ . '::sanitize');
        add_settings_section('woo_close_store_settings_section', '', '', 'woo_close_store_settings_sections');

        add_settings_field('closed_store', 'Imposta chiusura store.' ,  __CLASS__ . '::closed_store_callback' , 'woo_close_store_settings_sections', 'woo_close_store_settings_section');
        add_settings_field('closed_message', 'Messaggio per gli utenti <abbr class="required" title="required">*</abbr>',  __CLASS__ . '::closed_message_callback', 'woo_close_store_settings_sections', 'woo_close_store_settings_section');
    }

    /**
     * Sanitization Callback
     */
    private static function sanitize($input) {
        $sanitary_values = array();
        
        if (isset($input['closed_store']))
            $sanitary_values['closed_store'] = $input['closed_store'];
        
        if (isset($input['closed_message']))
            $sanitary_values['closed_message'] = esc_textarea($input['closed_message']);

        return $sanitary_values;
    }

    /**
     * Closed store mode
     */
    public static function closed_store_callback() {
        $options = get_option('woo_close_store_options');

        if (!isset($options['closed_store']))
            $closed_mode = '';
        else if ($options['closed_store'] === 'closed_store')
            $closed_mode = 'checked';

        printf('<input type="checkbox" name="woo_close_store_options[closed_store]" id="closed_store" value="closed_store" %s /> <label for="closed_store"><em><small>Vuoi impostare la modalità chiusura?</small></em></label>', $closed_mode);
    }

    /**
     * Notice Content.
     */
    public static function closed_message_callback() {
        $options = get_option('woo_close_store_options');

        if (!isset($options['closed_message']))
            $message = '';
        else
            $message = esc_attr($options['closed_message']);

        $placeholder = 'Il servizio di delivery è momentaneamente chiuso per manutenzione. Torniamo prima possibile!';
        printf('<textarea class="large-text" rows="5" name="woo_close_store_options[closed_message]" id="closed_message" placeholder="%s">%s</textarea>', $placeholder, $message);
    }

    /**
     * Retrieve plugin option value(s)
     */
    public static function closed_store() {
        $options = get_option('woo_close_store_options');

        if (!isset($options['closed_store'])) {
            update_option( 'woocommerce_demo_store', 'no');
            return;
        }
            
        remove_action('woocommerce_after_shop_loop_item', 'woocommerce_template_loop_add_to_cart', 10);
        remove_action('woocommerce_single_product_summary', 'woocommerce_template_single_add_to_cart', 30);
        remove_action('woocommerce_proceed_to_checkout', 'woocommerce_button_proceed_to_checkout', 20);
        remove_action('woocommerce_checkout_order_review', 'woocommerce_checkout_payment', 20);

        update_option( 'woocommerce_demo_store_notice', $options['closed_message'] );
        update_option( 'woocommerce_demo_store', 'yes');
    }

    /**
     * Override Woocommerce notice message.
     */
    public static function wc_custom_store_notice_updated( $text ) {
        $options = get_option('woo_close_store_options');
        $text = $options['closed_message'];

        return $text;
    }

    /**
     * Render and display plugin options page.
     */
    public static function render_woosubmenu_page() {
        ?>
        <div class="wrap">
            <h1><?php esc_html_e('Woo Close Store', 'woo-close-store'); ?></h1>
            <div id="poststuff">
                <div id="post-body" class="metabox-holder columns-1">
                    <?php settings_errors(); ?>
                    <!-- main content -->
                    <div id="post-body-content">
                        <form method="POST" id="woo-close-store" autocomplete="off" action="options.php">
                            <div class="meta-box-sortables ui-sortable">
                                <div class="postbox">
                                    <h2 class="hndle">
                                        <span>
                                            <?php esc_attr_e('Impostazioni', 'woo-close-store'); ?>
                                        </span>
                                    </h2>
                                    <div class="inside">
                                        <?php
                                            // Get settings fields
                                            settings_fields('woo_close_store_settings_fields');
                                            do_settings_sections('woo_close_store_settings_sections');
                                        ?>
                                    </div>
                                    <!-- .inside -->
                                </div>
                                <!-- .postbox -->
                            </div>
                            <!-- .meta-box-sortables .ui-sortable -->
                            <?php submit_button(); ?>
                        </form>
                    </div>
                    <!-- post-body-content -->
                </div>
                <!-- #post-body .metabox-holder .columns-1 -->
                <br class="clear">
            </div>
            <!-- #poststuff -->
        </div> <!-- .wrap -->
    <?php 
    }
}

Woo_Close_Store::init();