// Check that the consumer we are talking to is a valid consumer.
        $this->_checkConsumer();


        // Preparing the caching engine.
        $frontendOptions = array(
            'caching'                 => true,
            'cache_id_prefix'         => 'search_',
            'lifetime'                => 3*(24*60*60),  // 3 days
            'automatic_serialization' => true,
            'ignore_user_abort'       => true,
        );

        $backendOptions = array(
            'cache_dir'              => '/tmp',
            'hashed_directory_level' => 1,
        );

        $cache = Zend_Cache::factory('Core',
                                     'File',
                                     $frontendOptions,
                                     $backendOptions);

        
        // Check RPP count and displayed page.
        $pagination = $this->_getPagination(100, 1);
        
        // Check pagination limits
        if ($pagination['rpp'] > 100)
            $pagination['rpp'] = 100;


        $query = '';
        $terms = explode(' ', urldecode($keywords));
        for ($i=0; $i<count($terms); $i++)
        {
            $query .= "\"{$terms[$i]}\"";
            if ($i != count($terms) - 1)
                $query .= " AND ";
        }


        $front  = Zend_Controller_Front::getInstance();
	$params = $front->getRequest()->getParams();

        // Filter by country
        if (!empty($params['filter_by_country']))
        {
            $countries = explode(',', $params['filter_by_country']);

            $subquery = " AND (";
            $subquery .= "countries:{$countries[0]}";
            for ($i=1; $i<count($countries); $i++)
            {
                $subquery .= " OR countries:{$countries[$i]}";
            }
            $subquery .= ")";
            $query .= $subquery;
        }

        // Filter by category
        if (!empty($params['filter_by_category']))
        {
            $categories = explode(',', $params['filter_by_category']);

            $subquery = " AND (";
            $subquery .= "categories:{$categories[0]}";
            for ($i=1; $i<count($categories); $i++)
            {
                $subquery .= " AND categories:{$categories[$i]}";
            }
            $subquery .= ")";
            $query .= $subquery;
        }

        // Filter by subcategory
        if (!empty($params['filter_by_subcategory']))
        {
            $subcategories = explode(',', $params['filter_by_subcategory']);

            $subquery = " AND (";
            $subquery .= "subcategories:{$subcategories[0]}";
            for ($i=1; $i<count($subcategories); $i++)
            {
                $subquery .= " AND subcategories:{$subcategories[$i]}";
            }
            $subquery .= ")";
            $query .= $subquery;
        }


        // Hits are cached by query.
        $cachedItemID = md5($query);
        if(!$hits = $cache->load($cachedItemID))
        {
            // Cache miss, search and cache

            // Open the index
            $index = Zend_Search_Lucene::open('../data/products_index');

            // Limit the returned result set to prevent request timeouts.
            Zend_Search_Lucene::setResultSetLimit(500);

            $hits = $index->find($query);

            $newHits = array();
            foreach ($hits as $hitID => $hit)
            {
                $newHits[$hitID]['productID'] = $hit->productID;
                $newHits[$hitID]['price']     = $hit->price;
            }

            unset($hits);
            $hits = $newHits;

            // Cache hits returned
            $cache->save($hits, $cachedItemID);
        }


        // Determine categories/subcategories and their respective count
        $fcat = array();
        $fsub = array();
        foreach ($hits as $hit)
        {
            $product = new MyProject_Model_Product();
            $product->findByID($hit['productID']);
            if ($product->exists())
            {
                $vendors = $product->getVendors();
                foreach ($vendors as $vendor)
                {
                    $categories = $vendor->getCategories();
                    foreach ($categories as $category)
                    {
                        $fcat[$category[0]]['label_english'] = $category[1];
                        $fcat[$category[0]]['label_french'] = $category[2];
                        if (isset($fcat[$category[0]]['count']))
                            $fcat[$category[0]]['count']++;
                        else
                            $fcat[$category[0]]['count'] = 1;

                        $fsub[$category[3]]['label_english'] = $category[4];
                        $fsub[$category[3]]['label_french'] = $category[5];
                        if (isset($fsub[$category[3]]['count']))
                            $fsub[$category[3]]['count']++;
                        else
                            $fsub[$category[3]]['count'] = 1;
                        $fsub[$category[3]]['parent'] = $category[0];
                    }
                }
            }
        }


        // Append search results to answer.
        $answer = new MyProject_Rest_Answer_ProductsSearchResult(
            count($hits),
            $pagination['rpp'],
            $pagination['page']
        );
        $beginning = ($pagination['rpp'] * $pagination['page']) - $pagination['rpp'];
        $ending    = $pagination['rpp'] * $pagination['page'];

        $answer->appendCategories($fcat, $fsub);

        if (!empty($params['sort']))
        {
            $sorted = array();
            if ($params['sort'] == 'price-asc')
            {
                // Sort by prices
                foreach ($hits as $hitID =>$hit)
                {
                    $sorted[$hitID] = $hit['price'];
                }
                asort($sorted, SORT_NUMERIC);
            }
            
            if ($params['sort'] == 'price-desc')
            {
                // Sort by prices
                foreach ($hits as $hitID =>$hit)
                {
                    $sorted[$hitID] = $hit['price'];
                }
                arsort($sorted, SORT_NUMERIC);
            }

            // Set the array pointer to the beginning of the array
            reset($sorted);
            // Skip the unneed rows
            for ($i=0; $i<$beginning; $i++)
            {
                next($sorted);
            }
            // Fetch the needed rows
            for ($i=$beginning; $i<$ending; $i++)
            {
                if (empty($hits[key($sorted)]))
                    break;

                $product = new MyProject_Model_Product();
                $product->findByID($hits[key($sorted)]['productID']);

                $answer->append($product);

                next($sorted);
            }
        }
        else
        {
            for ($i=$beginning; $i<$ending; $i++)
            {
                if (empty($hits[$i]))
                    break;

                $product = new MyProject_Model_Product();
                $product->findByID($hits[$i]['productID']);

                $answer->append($product);
            }
        }
        

        return $answer->toXML();