Magento finding a product and options based on an arbitory string

magento_add_to_customer_cart.php

$_varien = new Varien_Object(array_merge(array(
	'product' => $product->getId(),
	'qty'     => 1,
), $optionsToUse));

/** @var Mage_Customer_Model_Customer $_customer */
foreach ($filters['customers'] as $_customer) {

	/**
	 * try to find a cart for the customer
	 */
	/** @var Mage_Sales_Model_Resource_Quote_Collection $_quoteLookup */
	$_quoteLookup = Mage::getModel('sales/quote')->getCollection();
	$_quoteLookup->addFieldToSelect('entity_id');
	$_quoteLookup->addFieldToFilter('customer_id', $_customer->getId());
	$_quoteLookup->addFieldToFilter('is_active', 1);
	$_quoteLookup->addOrder('entity_id', 'DESC');
	$_customerQuoteId = $_quoteLookup->load()->getFirstItem()->getId();


	/**
	 * no cart found so create one
	 */
	if (!$_customerQuoteId) {

		/** @var Mage_Checkout_Model_Cart_Api $cart_api */
		$cart_api = Mage::getModel('checkout/cart_api');
		$_customerQuoteId = $cart_api->create($this->_getStoreId());

	}

	$_currentCart = Mage::getModel('sales/quote')->loadByIdWithoutStore($_customerQuoteId);
	$_currentCart->setIsActive(true);

	/**
	 * Cloning the product is required as it gets modified somewhere down the code pile
	 */
	$_temp = clone $product;
	$res = $_currentCart->addProduct($_temp, $_varien);

	if(is_string($res)) // a string thrown is an error
		$this->_fault('cart_error', $res);

	$_currentCart->setCustomer($_customer);
	$_currentCart->assignCustomer($_customer);
	$_currentCart->collectTotals();
	$_currentCart->save();

}

magento_finding_options.php

$filters['options'] = 'large blue';

/** @var Mage_Catalog_Model_Product $product */
if($product->isConfigurable()) {

	$_bestSuitedAttributes = [];
	$_tmpOptions = $filters['options'];

	/** @var Mage_Catalog_Model_Product_Type_Configurable_Attribute $_attr */
	foreach ($product->getTypeInstance(true)->getConfigurableAttributes($product) as $_attr) {

		$_prices = $_attr->getPrices();
		if (is_array($_prices))
			foreach ($_prices as $_item) {

				foreach ($_tmpOptions as $_opt) {

					if ($_opt == strtolower($_item['label'])) {

						$_bestSuitedAttributes[$_opt] = array(
							'attribute_id'    => $_attr->getAttributeId(),
							'attribute_code'  => $_attr->getAttributeCode(),
							'attribute_label' => $_attr->getLabel(),
							'option_id'       => $_item['value_index'],
						);

						unset($_tmpOptions[$_opt]);

					}

				}

			}

	}

	/**
	 * If these two are equal, we found the correct product!
	 * convert the attributes to the array required later
	 */
	$optionsToUse = array('super_attribute' => array());
	if (count($_bestSuitedAttributes) == count($filters['options'])) {

		foreach ($_bestSuitedAttributes as $_attr)
			$optionsToUse['super_attribute'][(int) $_attr['attribute_id']] = (int) $_attr['option_id'];

	}

	if (empty($optionsToUse['super_attribute']))
		$this->_fault('product_not_found', "Configurable product found, but options didn't match");

}