Automatically Reduce Stock Level After Order in WooCommerce

Code

<?php
/**
 * Automatically reduce stock level in WooCommerce after an order is placed.
 *
 * This function hooks into the WooCommerce order status change to reduce stock levels
 * when an order is placed, preventing overselling and ensuring accurate inventory management.
 *
 * @param int $order_id The ID of the order.
 */
function wp_dudecom_reduce_stock_on_order_status_change( $order_id ) {
    // Get the order object
    $order = wc_get_order( $order_id );

    // Check if the order is valid
    if ( ! $order ) {
        return;
    }

    // Loop through each item in the order
    foreach ( $order->get_items() as $item_id => $item ) {
        // Get the product object
        $product = $item->get_product();

        // Check if the product manages stock
        if ( $product && $product->managing_stock() ) {
            // Get the current stock quantity
            $current_stock = $product->get_stock_quantity();

            // Calculate the new stock quantity
            $new_stock = $current_stock - $item->get_quantity();

            // Update the product stock quantity
            wc_update_product_stock( $product, $new_stock );
        }
    }
}
add_action( 'woocommerce_order_status_processing', 'wp_dudecom_reduce_stock_on_order_status_change', 10, 1 );
add_action( 'woocommerce_order_status_completed', 'wp_dudecom_reduce_stock_on_order_status_change', 10, 1 );
add_action( 'woocommerce_order_status_on-hold', 'wp_dudecom_reduce_stock_on_order_status_change', 10, 1 );
?>