ws_orderreference/classes/WebserviceSpecificManagementOrderreference.php

<?php
// You can do api/order_reference?id_order=12 or api/order_reference?id_cart=12

class WebserviceSpecificManagementOrderreference implements WebserviceSpecificManagementInterface
{
    private $objectOutput;
    private $wsObject;
    private ?array $result = null;

    public function setObjectOutput(WebserviceOutputBuilder $objectOutput)
    {
        $this->objectOutput = $objectOutput;
        return $this;
    }

    public function getObjectOutput()
    {
        return $this->objectOutput;
    }

    public function setWsObject(WebserviceRequest $wsObject)
    {
        $this->wsObject = $wsObject;
        return $this;
    }

    public function getWsObject()
    {
        return $this->wsObject;
    }

    public function manage()
    {
        $fragments = $this->wsObject ? $this->wsObject->urlFragments : [];

        if (isset($fragments['id_order'])) {
            $this->result = $this->fetchByOrderId((int) $fragments['id_order']);
        } elseif (isset($fragments['id_cart'])) {
            $this->result = $this->fetchByCartId((int) $fragments['id_cart']);
        }

        return true;
    }

    private function fetchByCartId(int $cartId): ?array
    {
        $row = Db::getInstance()->getRow(
            'SELECT id, id_cart, order_reference FROM ' . _DB_PREFIX_ . 'order_reference WHERE id_cart = ' . (int) $cartId
        );

        return $row ?: null;
    }

    private function fetchByOrderId(int $orderId): ?array
    {
        $idCart = Db::getInstance()->getValue(
            'SELECT id_cart FROM ' . _DB_PREFIX_ . 'orders WHERE id_order = ' . (int) $orderId
        );

        if ($idCart) {
            return $this->fetchByCartId((int) $idCart);
        }

        return null;
    }

    public function getContent()
    {
        $xml = new SimpleXMLElement('<order_references/>');

        if ($this->result !== null) {
            $node = $xml->addChild('order_reference');
            $node->addChild('id', (string) $this->result['id']);
            $node->addChild('id_cart', (string) $this->result['id_cart']);
            $node->addChild('reference', htmlspecialchars($this->result['order_reference']));
        }

        return $xml->asXML();
    }
}