old-new-wiaas/backend/app/plugins/wiaas/includes/api/class-wiaas-support-api.php

<?php

class Wiaas_Support_Api {

    /**
     * Endpoint namespace.
     *
     * @var string
     */
    private static $namespace = 'wiaas';

    private static $rest_base = 'support';


    public static function register_routes() {

        register_rest_route(self::$namespace,  self::$rest_base . '/send-support-email', array(
            'methods' => 'POST',
            'callback' => array(__CLASS__, 'send_support_email'),
            'permission_callback' => 'is_user_logged_in',
            'args' => array(
                'id' => array(
                    'description' => __('Order ID.', 'wiaas'),
                    'type' => 'integer',
                    'required' => true,
                    'sanitize_callback' => 'absint',
                ),
                'support_text' => array(
                    'description' => __('Email text.', 'wiaas'),
                    'type' => 'string',
                    'required' => true
                )
            )
        ));
    }

    /**
     * Send support email and save massage to order notes
     *
     * @param WP_REST_Request $request Request data.
     *
     * @return WP_REST_Response
     */
    public static function send_support_email($request) {

        $order_id = $request['id'];
        $message = $request['support_text'];
        $order = wc_get_order($order_id);
        $customer_id =   $order->get_customer_id();
        $customer = get_user_by('id', $customer_id);


        $mailer = WC()->mailer();

        $recipient = WIAAS_SUPPORT_EMAIL;
        $subject = __('Customer: '.$customer->get('first_name').', '.''.$customer->get('last_name').' needs support for order number: '  .$order->get_order_number());

        $headers = array();
        $success = $mailer->send( $recipient, $subject, $message, $headers );

        if ($success) {
            wc_create_order_note($order_id , $message, true  );
            return wiaas_api_notice('EMAIL_SENT', 'success');
        }

        return wiaas_api_notice('EMAIL_NOT_SENT', 'failed');
    }
}