/app/code/core/Mage/Catalog/Helper/Product.php

<?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/osl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@magentocommerce.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magentocommerce.com for more information.
 *
 * @category    Mage
 * @package     Mage_Catalog
 * @copyright   Copyright (c) 2010 Magento Inc. (http://www.magentocommerce.com)
 * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */

/**
 * Catalog category helper
 *
 * @author      Magento Core Team <core@magentocommerce.com>
 */
class Mage_Catalog_Helper_Product extends Mage_Core_Helper_Url
{
    const XML_PATH_PRODUCT_URL_SUFFIX           = 'catalog/seo/product_url_suffix';
    const XML_PATH_PRODUCT_URL_USE_CATEGORY     = 'catalog/seo/product_use_categories';
    const XML_PATH_USE_PRODUCT_CANONICAL_TAG    = 'catalog/seo/product_canonical_tag';

    /**
     * Cache for product rewrite suffix
     *
     * @var array
     */
    protected $_productUrlSuffix = array();

    protected $_statuses;

    protected $_priceBlock;

    /**
     * Retrieve product view page url
     *
     * @param   mixed $product
     * @return  string
     */
    public function getProductUrl($product)
    {
        if ($product instanceof Mage_Catalog_Model_Product) {
            return $product->getProductUrl();
        }
        elseif (is_numeric($product)) {
            return Mage::getModel('catalog/product')->load($product)->getProductUrl();
        }
        return false;
    }

    /**
     * Retrieve product price
     *
     * @param   Mage_Catalog_Model_Product $product
     * @return  float
     */
    public function getPrice($product)
    {
        return $product->getPrice();
    }

    /**
     * Retrieve product final price
     *
     * @param   Mage_Catalog_Model_Product $product
     * @return  float
     */
    public function getFinalPrice($product)
    {
        return $product->getFinalPrice();
    }

    /**
     * Retrieve base image url
     *
     * @return string
     */
    public function getImageUrl($product)
    {
        $url = false;
        if (!$product->getImage()) {
            $url = Mage::getDesign()->getSkinUrl('images/no_image.jpg');
        }
        elseif ($attribute = $product->getResource()->getAttribute('image')) {
            $url = $attribute->getFrontend()->getUrl($product);
        }
        return $url;
    }

    /**
     * Retrieve small image url
     *
     * @return unknown
     */
    public function getSmallImageUrl($product)
    {
        $url = false;
        if (!$product->getSmallImage()) {
            $url = Mage::getDesign()->getSkinUrl('images/no_image.jpg');
        }
        elseif ($attribute = $product->getResource()->getAttribute('small_image')) {
            $url = $attribute->getFrontend()->getUrl($product);
        }
        return $url;
    }

    /**
     * Retrieve thumbnail image url
     *
     * @return unknown
     */
    public function getThumbnailUrl($product)
    {
        return '';
    }

    public function getEmailToFriendUrl($product)
    {
        $categoryId = null;
        if ($category = Mage::registry('current_category')) {
            $categoryId = $category->getId();
        }
        return $this->_getUrl('sendfriend/product/send', array(
            'id' => $product->getId(),
            'cat_id' => $categoryId
        ));
    }

    public function getStatuses()
    {
        if(is_null($this->_statuses)) {
            $this->_statuses = array();//Mage::getModel('catalog/product_status')->getResourceCollection()->load();
        }

        return $this->_statuses;
    }

    /**
     * Check if a product can be shown
     *
     * @param  Mage_Catalog_Model_Product|int $product
     * @return boolean
     */
    public function canShow($product, $where = 'catalog')
    {
        if (is_int($product)) {
            $product = Mage::getModel('catalog/product')->load($product);
        }

        /* @var $product Mage_Catalog_Model_Product */

        if (!$product->getId()) {
            return false;
        }

        return $product->isVisibleInCatalog() && $product->isVisibleInSiteVisibility();
    }

    /**
     * Retrieve product rewrite sufix for store
     *
     * @param int $storeId
     * @return string
     */
    public function getProductUrlSuffix($storeId = null)
    {
        if (is_null($storeId)) {
            $storeId = Mage::app()->getStore()->getId();
        }

        if (!isset($this->_productUrlSuffix[$storeId])) {
            $this->_productUrlSuffix[$storeId] = Mage::getStoreConfig(self::XML_PATH_PRODUCT_URL_SUFFIX, $storeId);
        }
        return $this->_productUrlSuffix[$storeId];
    }

    /**
     * Check if <link rel="canonical"> can be used for product
     *
     * @param $store
     * @return bool
     */
    public function canUseCanonicalTag($store = null)
    {
        return Mage::getStoreConfig(self::XML_PATH_USE_PRODUCT_CANONICAL_TAG, $store);
    }

    /**
     * Return information array of product attribute input types
     * Only a small number of settings returned, so we won't break anything in current dataflow
     * As soon as development process goes on we need to add there all possible settings
     *
     * @param string $inputType
     * @return array
     */
    public function getAttributeInputTypes($inputType = null)
    {
        /**
        * @todo specify there all relations for properties depending on input type
        */
        $inputTypes = array(
            'multiselect'   => array(
                'backend_model'     => 'eav/entity_attribute_backend_array'
            ),
            'boolean'       => array(
                'source_model'      => 'eav/entity_attribute_source_boolean'
            )
        );

        if (is_null($inputType)) {
            return $inputTypes;
        } else if (isset($inputTypes[$inputType])) {
            return $inputTypes[$inputType];
        }
        return array();
    }

    /**
     * Return default attribute backend model by input type
     *
     * @param string $inputType
     * @return string|null
     */
    public function getAttributeBackendModelByInputType($inputType)
    {
        $inputTypes = $this->getAttributeInputTypes();
        if (!empty($inputTypes[$inputType]['backend_model'])) {
            return $inputTypes[$inputType]['backend_model'];
        }
        return null;
    }

    /**
     * Return default attribute source model by input type
     *
     * @param string $inputType
     * @return string|null
     */
    public function getAttributeSourceModelByInputType($inputType)
    {
        $inputTypes = $this->getAttributeInputTypes();
        if (!empty($inputTypes[$inputType]['source_model'])) {
            return $inputTypes[$inputType]['source_model'];
        }
        return null;
    }

    /**
     * Inits product to be used for product controller actions and layouts
     * $params can have following data:
     *   'category_id' - id of category to check and append to product as current.
     *     If empty (except FALSE) - will be guessed (e.g. from last visited) to load as current.
     *
     * @param int $productId
     * @param Mage_Core_Controller_Front_Action $controller
     * @param Varien_Object $params
     *
     * @return false|Mage_Catalog_Model_Product
     */
    public function initProduct($productId, $controller, $params = null)
    {
        // Prepare data for routine
        if (!$params) {
            $params = new Varien_Object();
        }

        // Init and load product
        Mage::dispatchEvent('catalog_controller_product_init_before', array('controller_action' => $controller));

        if (!$productId) {
            return false;
        }

        $product = Mage::getModel('catalog/product')
            ->setStoreId(Mage::app()->getStore()->getId())
            ->load($productId);

        if (!$this->canShow($product)) {
            return false;
        }
        if (!in_array(Mage::app()->getStore()->getWebsiteId(), $product->getWebsiteIds())) {
            return false;
        }

        // Load product current category
        $categoryId = $params->getCategoryId();
        if (!$categoryId && ($categoryId !== false)) {
            $lastId = Mage::getSingleton('catalog/session')->getLastVisitedCategoryId();
            if ($product->canBeShowInCategory($lastId)) {
                $categoryId = $lastId;
            }
        }

        if ($categoryId) {
            $category = Mage::getModel('catalog/category')->load($categoryId);
            $product->setCategory($category);
            Mage::register('current_category', $category);
        }

        // Register current data and dispatch final events
        Mage::register('current_product', $product);
        Mage::register('product', $product);

        try {
            Mage::dispatchEvent('catalog_controller_product_init', array('product' => $product));
            Mage::dispatchEvent('catalog_controller_product_init_after',
                            array('product' => $product,
                                'controller_action' => $controller
                            )
            );
        } catch (Mage_Core_Exception $e) {
            Mage::logException($e);
            return false;
        }

        return $product;
    }

    /**
     * Prepares product options by buyRequest: retrieves values and assigns them as default.
     * Also parses and adds product management related values - e.g. qty
     *
     * @param  Mage_Catalog_Model_Product $product
     * @param  Varien_Object $buyRequest
     * @return Mage_Catalog_Helper_Product
     */
    public function prepareProductOptions($product, $buyRequest)
    {
        $optionValues = $product->processBuyRequest($buyRequest);
        $optionValues->setQty($buyRequest->getQty());
        $product->setPreconfiguredValues($optionValues);

        return $this;
    }

    /**
     * Process $buyRequest and sets its options before saving configuration to some product item.
     * This method is used to attach additional parameters to processed buyRequest.
     *
     * $params holds parameters of what operation must be performed:
     * - 'current_config', Varien_Object or array - current buyRequest that configures product in this item,
     *   used to restore currently attached files
     * - 'files_prefix': string[a-z0-9_] - prefix that was added at frontend to names of file inputs,
     *   so they won't intersect with other submitted options
     *
     * @param Varien_Object|array $buyRequest
     * @param Varien_Object|array $params
     * @return Varien_Object
     */
    public function addParamsToBuyRequest($buyRequest, $params)
    {
        if (is_array($buyRequest)) {
            $buyRequest = new Varien_Object($buyRequest);
        }
        if (is_array($params)) {
            $params = new Varien_Object($params);
        }


        // Ensure that currentConfig goes as Varien_Object - for easier work with it later
        $currentConfig = $params->getCurrentConfig();
        if ($currentConfig) {
            if (is_array($currentConfig)) {
                $params->setCurrentConfig(new Varien_Object($currentConfig));
            } else if (!($currentConfig instanceof Varien_Object)) {
                $params->unsCurrentConfig();
            }
        }

        /*
         * Notice that '_processing_params' must always be object to protect processing forged requests
         * where '_processing_params' comes in $buyRequest as array from user input
         */
        $processingParams = $buyRequest->getData('_processing_params');
        if (!$processingParams || !($processingParams instanceof Varien_Object)) {
            $processingParams = new Varien_Object();
            $buyRequest->setData('_processing_params', $processingParams);
        }
        $processingParams->addData($params->getData());

        return $buyRequest;
    }

    /**
     * Return loaded product instance
     *
     * @param  int|string $productId (SKU or ID)
     * @param  int $store
     * @param  string $identifierType
     * @return Mage_Catalog_Model_Product
     */
    public function getProduct($productId, $store, $identifierType = null) {
        $loadByIdOnFalse = false;
        if ($identifierType == null) {
            if (is_string($productId) && !preg_match("/^[+-]?[1-9][0-9]*$|^0$/", $productId)) {
                $identifierType = 'sku';
                $loadByIdOnFalse = true;
            } else {
                $identifierType = 'id';
            }
        }

        /** @var $product Mage_Catalog_Model_Product */
        $product = Mage::getModel('catalog/product');
        if ($store !== null) {
            $product->setStoreId($store);
        }
        if ($identifierType == 'sku') {
            $idBySku = $product->getIdBySku($productId);
            if ($idBySku) {
                $productId = $idBySku;
            }
            if ($loadByIdOnFalse) {
                $identifierType = 'id';
            }
        }

        if ($identifierType == 'id' && is_numeric($productId)) {
            $productId = !is_float($productId) ? (int) $productId : 0;
            $product->load($productId);
        }

        return $product;
    }

}