JetFromBuilder - Call hook - Woo product Stock modification (like preorder)

code

// place the code in the child theme functions.php or a custom code snippets plugin, like FluentSnippets
// What do this code

// What this Call hook does is to extract the product identifier from the field that is filled, 
// and the order quantity from the quantity field. It checks when the form is submitted 
// if there is enough of the product in stock, if so, it subtracts the quantity when the form is submitted. 
// If there is not enough, an error is generated and the stock of the product is not changed.

// This code does not require the JFB Add to cart add-on. The hook does not go through the checkout process, 
// it only adjusts the stock of the product based on the quantity of the order the user has submitted.

// Example image: https://prnt.sc/WpJXbOlExK__

// If the quantity entered is greater than the quantity in stock, 
// an error message will be displayed, you can change the text in the code

// HOW TO USE
// Create your jetformbuilder form. Create a select field where you will list your products,
// (The point is that your field can return the product id, from which the code works)
// and a quantity field (suggested number field type)
// This 2 field required to work properly this Call hook action
// In the  code change this two line and replace with your own form field name:
// $product_id = intval($request['products']); // change the 'products' with your Form field name
// $quantity = intval($request['quantity']);  // change the 'quantity' with your Form field name

// in the jetformbuilder add a Call Hook post submit action top of the list, and paste this name: check-product-stock
// example image: https://prnt.sc/eygOolauR5GF

use Jet_Form_Builder\Exceptions\Action_Exception;

add_filter('jet-form-builder/custom-filter/check-product-stock', function($result, $request, $action_handler) {

    // Check if WooCommerce is active
    if (!class_exists('WC_Product')) {
        return $result;
    }

    if (isset($request['products']) && isset($request['quantity'])) {
        $product_id = intval($request['products']); // change the 'products' with your Form field name
        $quantity = intval($request['quantity']);  // change the 'quantity' with your Form field name

        // Get the product object
        $product = wc_get_product($product_id);
        if (!$product) {
            throw new Action_Exception('Invalid product selected.', 'failed');
        }

        // Get the current stock quantity
        $stock_quantity = $product->get_stock_quantity();

        // Check if stock management is enabled and stock quantity is set
        if ($stock_quantity === null) {
            // If stock quantity is null, stock management might be disabled
            // You can choose to allow or deny the submission here
            return $result;
        }

        // Check if the product is in stock
        if (!$product->is_in_stock() || $stock_quantity <= 0) {
            throw new Action_Exception('Not available in such a large quantity (maximum available: 0)', 'failed'); // change your text here
        }

        // Check if there is enough stock (equality is acceptable)
        if ($stock_quantity < $quantity) {
            throw new Action_Exception('Not available in such a large quantity (maximum available: ' . $stock_quantity . ')', 'failed'); // change your text here
        }

        // Reduce the stock by the requested quantity
        $new_stock = $stock_quantity - $quantity;
        $product->set_stock_quantity($new_stock);
        $product->save();

        // Allow the form submission to proceed
        return $result;

    } else {
        throw new Action_Exception('Required fields are missing.', 'failed'); // change your text here
    }

}, 10, 3);
?>