/home/preegmxb/byeaglytics-co.com/administrator/components/com_finder/src/Indexer/Indexer.php
<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_finder
 *
 * @copyright   (C) 2011 Open Source Matters, Inc. <https://www.joomla.org>
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

namespace Joomla\Component\Finder\Administrator\Indexer;

\defined('_JEXEC') or die;

use Exception;
use Joomla\CMS\Component\ComponentHelper;
use Joomla\CMS\Factory;
use Joomla\CMS\Filesystem\File;
use Joomla\CMS\Object\CMSObject;
use Joomla\CMS\Plugin\PluginHelper;
use Joomla\CMS\Profiler\Profiler;
use Joomla\Database\ParameterType;
use Joomla\Database\QueryInterface;
use Joomla\String\StringHelper;

/**
 * Main indexer class for the Finder indexer package.
 *
 * The indexer class provides the core functionality of the Finder
 * search engine. It is responsible for adding and updating the
 * content links table; extracting and scoring tokens; and maintaining
 * all referential information for the content.
 *
 * Note: All exceptions thrown from within this class should be caught
 * by the controller.
 *
 * @since  2.5
 */
class Indexer
{
	/**
	 * The title context identifier.
	 *
	 * @var    integer
	 * @since  2.5
	 */
	const TITLE_CONTEXT = 1;

	/**
	 * The text context identifier.
	 *
	 * @var    integer
	 * @since  2.5
	 */
	const TEXT_CONTEXT = 2;

	/**
	 * The meta context identifier.
	 *
	 * @var    integer
	 * @since  2.5
	 */
	const META_CONTEXT = 3;

	/**
	 * The path context identifier.
	 *
	 * @var    integer
	 * @since  2.5
	 */
	const PATH_CONTEXT = 4;

	/**
	 * The misc context identifier.
	 *
	 * @var    integer
	 * @since  2.5
	 */
	const MISC_CONTEXT = 5;

	/**
	 * The indexer state object.
	 *
	 * @var    CMSObject
	 * @since  2.5
	 */
	public static $state;

	/**
	 * The indexer profiler object.
	 *
	 * @var    Profiler
	 * @since  2.5
	 */
	public static $profiler;

	/**
	 * Database driver cache.
	 *
	 * @var    \Joomla\Database\DatabaseDriver
	 * @since  3.8.0
	 */
	protected $db;

	/**
	 * Reusable Query Template. To be used with clone.
	 *
	 * @var    QueryInterface
	 * @since  3.8.0
	 */
	protected $addTokensToDbQueryTemplate;

	/**
	 * Indexer constructor.
	 *
	 * @since  3.8.0
	 */
	public function __construct()
	{
		$this->db = Factory::getDbo();

		$db = $this->db;

		// Set up query template for addTokensToDb
		$this->addTokensToDbQueryTemplate = $db->getQuery(true)->insert($db->quoteName('#__finder_tokens'))
			->columns(
				array(
					$db->quoteName('term'),
					$db->quoteName('stem'),
					$db->quoteName('common'),
					$db->quoteName('phrase'),
					$db->quoteName('weight'),
					$db->quoteName('context'),
					$db->quoteName('language')
				)
			);
	}

	/**
	 * Method to get the indexer state.
	 *
	 * @return  object  The indexer state object.
	 *
	 * @since   2.5
	 */
	public static function getState()
	{
		// First, try to load from the internal state.
		if ((bool) static::$state)
		{
			return static::$state;
		}

		// If we couldn't load from the internal state, try the session.
		$session = Factory::getSession();
		$data = $session->get('_finder.state', null);

		// If the state is empty, load the values for the first time.
		if (empty($data))
		{
			$data = new CMSObject;

			// Load the default configuration options.
			$data->options = ComponentHelper::getParams('com_finder');

			// Setup the weight lookup information.
			$data->weights = array(
				self::TITLE_CONTEXT => round($data->options->get('title_multiplier', 1.7), 2),
				self::TEXT_CONTEXT  => round($data->options->get('text_multiplier', 0.7), 2),
				self::META_CONTEXT  => round($data->options->get('meta_multiplier', 1.2), 2),
				self::PATH_CONTEXT  => round($data->options->get('path_multiplier', 2.0), 2),
				self::MISC_CONTEXT  => round($data->options->get('misc_multiplier', 0.3), 2)
			);

			// Set the current time as the start time.
			$data->startTime = Factory::getDate()->toSql();

			// Set the remaining default values.
			$data->batchSize   = (int) $data->options->get('batch_size', 50);
			$data->batchOffset = 0;
			$data->totalItems  = 0;
			$data->pluginState = array();
		}

		// Setup the profiler if debugging is enabled.
		if (Factory::getApplication()->get('debug'))
		{
			static::$profiler = Profiler::getInstance('FinderIndexer');
		}

		// Set the state.
		static::$state = $data;

		return static::$state;
	}

	/**
	 * Method to set the indexer state.
	 *
	 * @param   CMSObject  $data  A new indexer state object.
	 *
	 * @return  boolean  True on success, false on failure.
	 *
	 * @since   2.5
	 */
	public static function setState($data)
	{
		// Check the state object.
		if (empty($data) || !$data instanceof CMSObject)
		{
			return false;
		}

		// Set the new internal state.
		static::$state = $data;

		// Set the new session state.
		Factory::getSession()->set('_finder.state', $data);

		return true;
	}

	/**
	 * Method to reset the indexer state.
	 *
	 * @return  void
	 *
	 * @since   2.5
	 */
	public static function resetState()
	{
		// Reset the internal state to null.
		self::$state = null;

		// Reset the session state to null.
		Factory::getSession()->set('_finder.state', null);
	}

	/**
	 * Method to index a content item.
	 *
	 * @param   Result  $item    The content item to index.
	 * @param   string  $format  The format of the content. [optional]
	 *
	 * @return  integer  The ID of the record in the links table.
	 *
	 * @since   2.5
	 * @throws  \Exception on database error.
	 */
	public function index($item, $format = 'html')
	{
		// Mark beforeIndexing in the profiler.
		static::$profiler ? static::$profiler->mark('beforeIndexing') : null;
		$db = $this->db;
		$serverType = strtolower($db->getServerType());

		// Check if the item is in the database.
		$query = $db->getQuery(true)
			->select($db->quoteName('link_id') . ', ' . $db->quoteName('md5sum'))
			->from($db->quoteName('#__finder_links'))
			->where($db->quoteName('url') . ' = ' . $db->quote($item->url));

		// Load the item  from the database.
		$db->setQuery($query);
		$link = $db->loadObject();

		// Get the indexer state.
		$state = static::getState();

		// Get the signatures of the item.
		$curSig = static::getSignature($item);
		$oldSig = $link->md5sum ?? null;

		// Get the other item information.
		$linkId = empty($link->link_id) ? null : $link->link_id;
		$isNew = empty($link->link_id);

		// Check the signatures. If they match, the item is up to date.
		if (!$isNew && $curSig == $oldSig)
		{
			return $linkId;
		}

		/*
		 * If the link already exists, flush all the term maps for the item.
		 * Maps are stored in 16 tables so we need to iterate through and flush
		 * each table one at a time.
		 */
		if (!$isNew)
		{
			// Flush the maps for the link.
			$query->clear()
				->delete($db->quoteName('#__finder_links_terms'))
				->where($db->quoteName('link_id') . ' = ' . (int) $linkId);
			$db->setQuery($query);
			$db->execute();

			// Remove the taxonomy maps.
			Taxonomy::removeMaps($linkId);
		}

		// Mark afterUnmapping in the profiler.
		static::$profiler ? static::$profiler->mark('afterUnmapping') : null;

		// Perform cleanup on the item data.
		$item->publish_start_date = (int) $item->publish_start_date != 0 ? $item->publish_start_date : null;
		$item->publish_end_date = (int) $item->publish_end_date != 0 ? $item->publish_end_date : null;
		$item->start_date = (int) $item->start_date != 0 ? $item->start_date : null;
		$item->end_date = (int) $item->end_date != 0 ? $item->end_date : null;

		// Prepare the item description.
		$item->description = Helper::parse($item->summary);

		/*
		 * Now, we need to enter the item into the links table. If the item
		 * already exists in the database, we need to use an UPDATE query.
		 * Otherwise, we need to use an INSERT to get the link id back.
		 */
		$entry = new \stdClass;
		$entry->url = $item->url;
		$entry->route = $item->route;
		$entry->title = $item->title;

		// We are shortening the description in order to not run into length issues with this field
		$entry->description = StringHelper::substr($item->description, 0, 32000);
		$entry->indexdate = Factory::getDate()->toSql();
		$entry->state = (int) $item->state;
		$entry->access = (int) $item->access;
		$entry->language = $item->language;
		$entry->type_id = (int) $item->type_id;
		$entry->object = '';
		$entry->publish_start_date = $item->publish_start_date;
		$entry->publish_end_date = $item->publish_end_date;
		$entry->start_date = $item->start_date;
		$entry->end_date = $item->end_date;
		$entry->list_price = (double) ($item->list_price ?: 0);
		$entry->sale_price = (double) ($item->sale_price ?: 0);

		if ($isNew)
		{
			// Insert the link and get its id.
			$db->insertObject('#__finder_links', $entry);
			$linkId = (int) $db->insertid();
		}
		else
		{
			// Update the link.
			$entry->link_id = $linkId;
			$db->updateObject('#__finder_links', $entry, 'link_id');
		}

		// Set up the variables we will need during processing.
		$count = 0;

		// Mark afterLinking in the profiler.
		static::$profiler ? static::$profiler->mark('afterLinking') : null;

		// Truncate the tokens tables.
		$db->truncateTable('#__finder_tokens');

		// Truncate the tokens aggregate table.
		$db->truncateTable('#__finder_tokens_aggregate');

		/*
		 * Process the item's content. The items can customize their
		 * processing instructions to define extra properties to process
		 * or rearrange how properties are weighted.
		 */
		foreach ($item->getInstructions() as $group => $properties)
		{
			// Iterate through the properties of the group.
			foreach ($properties as $property)
			{
				// Check if the property exists in the item.
				if (empty($item->$property))
				{
					continue;
				}

				// Tokenize the property.
				if (is_array($item->$property))
				{
					// Tokenize an array of content and add it to the database.
					foreach ($item->$property as $ip)
					{
						/*
						 * If the group is path, we need to a few extra processing
						 * steps to strip the extension and convert slashes and dashes
						 * to spaces.
						 */
						if ($group === static::PATH_CONTEXT)
						{
							$ip = File::stripExt($ip);
							$ip = str_replace(array('/', '-'), ' ', $ip);
						}

						// Tokenize a string of content and add it to the database.
						$count += $this->tokenizeToDb($ip, $group, $item->language, $format);

						// Check if we're approaching the memory limit of the token table.
						if ($count > static::$state->options->get('memory_table_limit', 30000))
						{
							$this->toggleTables(false);
						}
					}
				}
				else
				{
					/*
					 * If the group is path, we need to a few extra processing
					 * steps to strip the extension and convert slashes and dashes
					 * to spaces.
					 */
					if ($group === static::PATH_CONTEXT)
					{
						$item->$property = File::stripExt($item->$property);
						$item->$property = str_replace('/', ' ', $item->$property);
						$item->$property = str_replace('-', ' ', $item->$property);
					}

					// Tokenize a string of content and add it to the database.
					$count += $this->tokenizeToDb($item->$property, $group, $item->language, $format);

					// Check if we're approaching the memory limit of the token table.
					if ($count > static::$state->options->get('memory_table_limit', 30000))
					{
						$this->toggleTables(false);
					}
				}
			}
		}

		/*
		 * Process the item's taxonomy. The items can customize their
		 * taxonomy mappings to define extra properties to map.
		 */
		foreach ($item->getTaxonomy() as $branch => $nodes)
		{
			// Iterate through the nodes and map them to the branch.
			foreach ($nodes as $node)
			{
				// Add the node to the tree.
				if ($node->nested)
				{
					$nodeId = Taxonomy::addNestedNode($branch, $node->node, $node->state, $node->access, $node->language);
				}
				else
				{
					$nodeId = Taxonomy::addNode($branch, $node->title, $node->state, $node->access, $node->language);
				}

				// Add the link => node map.
				Taxonomy::addMap($linkId, $nodeId);
				$node->id = $nodeId;
			}
		}

		// Mark afterProcessing in the profiler.
		static::$profiler ? static::$profiler->mark('afterProcessing') : null;

		/*
		 * At this point, all of the item's content has been parsed, tokenized
		 * and inserted into the #__finder_tokens table. Now, we need to
		 * aggregate all the data into that table into a more usable form. The
		 * aggregated data will be inserted into #__finder_tokens_aggregate
		 * table.
		 */
		$query = 'INSERT INTO ' . $db->quoteName('#__finder_tokens_aggregate') .
			' (' . $db->quoteName('term_id') .
			', ' . $db->quoteName('term') .
			', ' . $db->quoteName('stem') .
			', ' . $db->quoteName('common') .
			', ' . $db->quoteName('phrase') .
			', ' . $db->quoteName('term_weight') .
			', ' . $db->quoteName('context') .
			', ' . $db->quoteName('context_weight') .
			', ' . $db->quoteName('total_weight') .
			', ' . $db->quoteName('language') . ')' .
			' SELECT' .
			' COALESCE(t.term_id, 0), t1.term, t1.stem, t1.common, t1.phrase, t1.weight, t1.context,' .
			' ROUND( t1.weight * COUNT( t2.term ) * %F, 8 ) AS context_weight, 0, t1.language' .
			' FROM (' .
			'   SELECT DISTINCT t1.term, t1.stem, t1.common, t1.phrase, t1.weight, t1.context, t1.language' .
			'   FROM ' . $db->quoteName('#__finder_tokens') . ' AS t1' .
			'   WHERE t1.context = %d' .
			' ) AS t1' .
			' JOIN ' . $db->quoteName('#__finder_tokens') . ' AS t2 ON t2.term = t1.term AND t2.language = t1.language' .
			' LEFT JOIN ' . $db->quoteName('#__finder_terms') . ' AS t ON t.term = t1.term AND t.language = t1.language' .
			' WHERE t2.context = %d' .
			' GROUP BY t1.term, t.term_id, t1.term, t1.stem, t1.common, t1.phrase, t1.weight, t1.context, t1.language' .
			' ORDER BY t1.term DESC';

		// Iterate through the contexts and aggregate the tokens per context.
		foreach ($state->weights as $context => $multiplier)
		{
			// Run the query to aggregate the tokens for this context..
			$db->setQuery(sprintf($query, $multiplier, $context, $context));
			$db->execute();
		}

		// Mark afterAggregating in the profiler.
		static::$profiler ? static::$profiler->mark('afterAggregating') : null;

		/*
		 * When we pulled down all of the aggregate data, we did a LEFT JOIN
		 * over the terms table to try to find all the term ids that
		 * already exist for our tokens. If any of the rows in the aggregate
		 * table have a term of 0, then no term record exists for that
		 * term so we need to add it to the terms table.
		 */
		$db->setQuery(
			'INSERT INTO ' . $db->quoteName('#__finder_terms') .
			' (' . $db->quoteName('term') .
			', ' . $db->quoteName('stem') .
			', ' . $db->quoteName('common') .
			', ' . $db->quoteName('phrase') .
			', ' . $db->quoteName('weight') .
			', ' . $db->quoteName('soundex') .
			', ' . $db->quoteName('language') . ')' .
			' SELECT ta.term, ta.stem, ta.common, ta.phrase, ta.term_weight, SOUNDEX(ta.term), ta.language' .
			' FROM ' . $db->quoteName('#__finder_tokens_aggregate') . ' AS ta' .
			' WHERE ta.term_id = 0' .
			' GROUP BY ta.term, ta.stem, ta.common, ta.phrase, ta.term_weight, SOUNDEX(ta.term), ta.language'
		);
		$db->execute();

		/*
		 * Now, we just inserted a bunch of new records into the terms table
		 * so we need to go back and update the aggregate table with all the
		 * new term ids.
		 */
		$query = $db->getQuery(true)
			->update($db->quoteName('#__finder_tokens_aggregate', 'ta'))
			->innerJoin($db->quoteName('#__finder_terms', 't'), 't.term = ta.term AND t.language = ta.language')
			->where('ta.term_id = 0');

		if ($serverType == 'mysql')
		{
			$query->set($db->quoteName('ta.term_id') . ' = ' . $db->quoteName('t.term_id'));
		}
		else
		{
			$query->set($db->quoteName('term_id') . ' = ' . $db->quoteName('t.term_id'));
		}

		$db->setQuery($query);
		$db->execute();

		// Mark afterTerms in the profiler.
		static::$profiler ? static::$profiler->mark('afterTerms') : null;

		/*
		 * After we've made sure that all of the terms are in the terms table
		 * and the aggregate table has the correct term ids, we need to update
		 * the links counter for each term by one.
		 */
		$query->clear()
			->update($db->quoteName('#__finder_terms', 't'))
			->innerJoin($db->quoteName('#__finder_tokens_aggregate', 'ta'), 'ta.term_id = t.term_id');

		if ($serverType == 'mysql')
		{
			$query->set($db->quoteName('t.links') . ' = t.links + 1');
		}
		else
		{
			$query->set($db->quoteName('links') . ' = t.links + 1');
		}

		$db->setQuery($query);
		$db->execute();

		// Mark afterTerms in the profiler.
		static::$profiler ? static::$profiler->mark('afterTerms') : null;

		/*
		 * At this point, the aggregate table contains a record for each
		 * term in each context. So, we're going to pull down all of that
		 * data while grouping the records by term and add all of the
		 * sub-totals together to arrive at the final total for each token for
		 * this link. Then, we insert all of that data into the mapping table.
		 */
		$db->setQuery(
			'INSERT INTO ' . $db->quoteName('#__finder_links_terms') .
			' (' . $db->quoteName('link_id') .
			', ' . $db->quoteName('term_id') .
			', ' . $db->quoteName('weight') . ')' .
			' SELECT ' . (int) $linkId . ', ' . $db->quoteName('term_id') . ',' .
			' ROUND(SUM(' . $db->quoteName('context_weight') . '), 8)' .
			' FROM ' . $db->quoteName('#__finder_tokens_aggregate') .
			' GROUP BY ' . $db->quoteName('term') . ', ' . $db->quoteName('term_id') .
			' ORDER BY ' . $db->quoteName('term') . ' DESC'
		);
		$db->execute();

		// Mark afterMapping in the profiler.
		static::$profiler ? static::$profiler->mark('afterMapping') : null;

		// Update the signature.
		$object = serialize($item);
		$query->clear()
			->update($db->quoteName('#__finder_links'))
			->set($db->quoteName('md5sum') . ' = :md5sum')
			->set($db->quoteName('object') . ' = :object')
			->where($db->quoteName('link_id') . ' = :linkid')
			->bind(':md5sum', $curSig)
			->bind(':object', $object, ParameterType::LARGE_OBJECT)
			->bind(':linkid', $linkId, ParameterType::INTEGER);
		$db->setQuery($query);
		$db->execute();

		// Mark afterSigning in the profiler.
		static::$profiler ? static::$profiler->mark('afterSigning') : null;

		// Truncate the tokens tables.
		$db->truncateTable('#__finder_tokens');

		// Truncate the tokens aggregate table.
		$db->truncateTable('#__finder_tokens_aggregate');

		// Toggle the token tables back to memory tables.
		$this->toggleTables(true);

		// Mark afterTruncating in the profiler.
		static::$profiler ? static::$profiler->mark('afterTruncating') : null;

		// Trigger a plugin event after indexing
		PluginHelper::importPlugin('finder');
		Factory::getApplication()->triggerEvent('onFinderIndexAfterIndex', array($item, $linkId));

		return $linkId;
	}

	/**
	 * Method to remove a link from the index.
	 *
	 * @param   integer  $linkId            The id of the link.
	 * @param   bool     $removeTaxonomies  Remove empty taxonomies
	 *
	 * @return  boolean  True on success.
	 *
	 * @since   2.5
	 * @throws  Exception on database error.
	 */
	public function remove($linkId, $removeTaxonomies = true)
	{
		$db     = $this->db;
		$query  = $db->getQuery(true);
		$linkId = (int) $linkId;

		// Update the link counts for the terms.
		$query->clear()
			->update($db->quoteName('#__finder_terms', 't'))
			->join('INNER', $db->quoteName('#__finder_links_terms', 'm'), $db->quoteName('m.term_id') . ' = ' . $db->quoteName('t.term_id'))
			->set($db->quoteName('links') . ' = ' . $db->quoteName('links') . ' - 1')
			->where($db->quoteName('m.link_id') . ' = :linkid')
			->bind(':linkid', $linkId, ParameterType::INTEGER);
		$db->setQuery($query)->execute();

		// Remove all records from the mapping tables.
		$query->clear()
			->delete($db->quoteName('#__finder_links_terms'))
			->where($db->quoteName('link_id') . ' = :linkid')
			->bind(':linkid', $linkId, ParameterType::INTEGER);
		$db->setQuery($query)->execute();

		// Delete all orphaned terms.
		$query->clear()
			->delete($db->quoteName('#__finder_terms'))
			->where($db->quoteName('links') . ' <= 0');
		$db->setQuery($query)->execute();

		// Delete the link from the index.
		$query->clear()
			->delete($db->quoteName('#__finder_links'))
			->where($db->quoteName('link_id') . ' = :linkid')
			->bind(':linkid', $linkId, ParameterType::INTEGER);
		$db->setQuery($query)->execute();

		// Remove the taxonomy maps.
		Taxonomy::removeMaps($linkId);

		// Remove the orphaned taxonomy nodes.
		if ($removeTaxonomies)
		{
			Taxonomy::removeOrphanNodes();
		}

		PluginHelper::importPlugin('finder');
		Factory::getApplication()->triggerEvent('onFinderIndexAfterDelete', array($linkId));

		return true;
	}

	/**
	 * Method to optimize the index. We use this method to remove unused terms
	 * and any other optimizations that might be necessary.
	 *
	 * @return  boolean  True on success.
	 *
	 * @since   2.5
	 * @throws  Exception on database error.
	 */
	public function optimize()
	{
		// Get the database object.
		$db = $this->db;
		$serverType = strtolower($db->getServerType());
		$query = $db->getQuery(true);

		// Delete all orphaned terms.
		$query->delete($db->quoteName('#__finder_terms'))
			->where($db->quoteName('links') . ' <= 0');
		$db->setQuery($query);
		$db->execute();

		// Remove the orphaned taxonomy nodes.
		Taxonomy::removeOrphanNodes();

		// Optimize the tables.
		$tables = [
			'#__finder_links',
			'#__finder_links_terms',
			'#__finder_filters',
			'#__finder_terms_common',
			'#__finder_types',
			'#__finder_taxonomy_map',
			'#__finder_taxonomy'
		];

		foreach ($tables as $table)
		{
			if ($serverType == 'mysql')
			{
				$db->setQuery('OPTIMIZE TABLE ' . $db->quoteName($table));
				$db->execute();
			}
			else
			{
				$db->setQuery('VACUUM ' . $db->quoteName($table));
				$db->execute();
				$db->setQuery('REINDEX TABLE ' . $db->quoteName($table));
				$db->execute();
			}
		}

		return true;
	}

	/**
	 * Method to get a content item's signature.
	 *
	 * @param   object  $item  The content item to index.
	 *
	 * @return  string  The content item's signature.
	 *
	 * @since   2.5
	 */
	protected static function getSignature($item)
	{
		// Get the indexer state.
		$state = static::getState();

		// Get the relevant configuration variables.
		$config = array(
			$state->weights,
			$state->options->get('stem', 1),
			$state->options->get('stemmer', 'porter_en')
		);

		return md5(serialize(array($item, $config)));
	}

	/**
	 * Method to parse input, tokenize it, and then add it to the database.
	 *
	 * @param   mixed    $input    String or resource to use as input. A resource input will automatically be chunked to conserve
	 *                             memory. Strings will be chunked if longer than 2K in size.
	 * @param   integer  $context  The context of the input. See context constants.
	 * @param   string   $lang     The language of the input.
	 * @param   string   $format   The format of the input.
	 *
	 * @return  integer  The number of tokens extracted from the input.
	 *
	 * @since   2.5
	 */
	protected function tokenizeToDb($input, $context, $lang, $format)
	{
		$count = 0;
		$buffer = null;

		if (empty($input))
		{
			return $count;
		}

		// If the input is a resource, batch the process out.
		if (is_resource($input))
		{
			// Batch the process out to avoid memory limits.
			while (!feof($input))
			{
				// Read into the buffer.
				$buffer .= fread($input, 2048);

				/*
				 * If we haven't reached the end of the file, seek to the last
				 * space character and drop whatever is after that to make sure
				 * we didn't truncate a term while reading the input.
				 */
				if (!feof($input))
				{
					// Find the last space character.
					$ls = strrpos($buffer, ' ');

					// Adjust string based on the last space character.
					if ($ls)
					{
						// Truncate the string to the last space character.
						$string = substr($buffer, 0, $ls);

						// Adjust the buffer based on the last space for the next iteration and trim.
						$buffer = StringHelper::trim(substr($buffer, $ls));
					}
					// No space character was found.
					else
					{
						$string = $buffer;
					}
				}
				// We've reached the end of the file, so parse whatever remains.
				else
				{
					$string = $buffer;
				}

				// Parse, tokenise and add tokens to the database.
				$count = $this->tokenizeToDbShort($string, $context, $lang, $format, $count);

				unset($string);
			}

			return $count;
		}

		// Parse, tokenise and add tokens to the database.
		$count = $this->tokenizeToDbShort($input, $context, $lang, $format, $count);

		return $count;
	}

	/**
	 * Method to parse input, tokenise it, then add the tokens to the database.
	 *
	 * @param   string   $input    String to parse, tokenise and add to database.
	 * @param   integer  $context  The context of the input. See context constants.
	 * @param   string   $lang     The language of the input.
	 * @param   string   $format   The format of the input.
	 * @param   integer  $count    The number of tokens processed so far.
	 *
	 * @return  integer  Cumulative number of tokens extracted from the input so far.
	 *
	 * @since   3.7.0
	 */
	private function tokenizeToDbShort($input, $context, $lang, $format, $count)
	{
		// Parse the input.
		$input = Helper::parse($input, $format);

		// Check the input.
		if (empty($input))
		{
			return $count;
		}

		// Tokenize the input.
		$tokens = Helper::tokenize($input, $lang);

		if (count($tokens) == 0)
		{
			return $count;
		}

		// Add the tokens to the database.
		$count += $this->addTokensToDb($tokens, $context);

		// Check if we're approaching the memory limit of the token table.
		if ($count > static::$state->options->get('memory_table_limit', 10000))
		{
			$this->toggleTables(false);
		}

		return $count;
	}

	/**
	 * Method to add a set of tokens to the database.
	 *
	 * @param   Token[]|Token  $tokens   An array or single Token object.
	 * @param   mixed          $context  The context of the tokens. See context constants. [optional]
	 *
	 * @return  integer  The number of tokens inserted into the database.
	 *
	 * @since   2.5
	 * @throws  Exception on database error.
	 */
	protected function addTokensToDb($tokens, $context = '')
	{
		static $filterCommon, $filterNumeric;

		if (is_null($filterCommon))
		{
			$params = ComponentHelper::getParams('com_finder');
			$filterCommon = $params->get('filter_commonwords', false);
			$filterNumeric = $params->get('filter_numerics', false);
		}

		// Get the database object.
		$db = $this->db;

		$query = clone $this->addTokensToDbQueryTemplate;

		// Check if a single FinderIndexerToken object was given and make it to be an array of FinderIndexerToken objects
		$tokens = is_array($tokens) ? $tokens : array($tokens);

		// Count the number of token values.
		$values = 0;

		// Break into chunks of no more than 128 items
		$chunks = array_chunk($tokens, 128);

		foreach ($chunks as $tokens)
		{
			$query->clear('values');

			foreach ($tokens as $token)
			{
				if ($filterCommon && $token->common)
				{
					continue;
				}

				if ($filterNumeric && $token->numeric)
				{
					continue;
				}

				$query->values(
					$db->quote($token->term) . ', '
					. $db->quote($token->stem) . ', '
					. (int) $token->common . ', '
					. (int) $token->phrase . ', '
					. $db->quote($token->weight) . ', '
					. (int) $context . ', '
					. $db->quote($token->language)
				);
				++$values;
			}

			$db->setQuery($query)->execute();

			// Check if we're approaching the memory limit of the token table.
			if ($values > static::$state->options->get('memory_table_limit', 10000))
			{
				$this->toggleTables(false);
			}
		}

		return $values;
	}

	/**
	 * Method to switch the token tables from Memory tables to Disk tables
	 * when they are close to running out of memory.
	 * Since this is not supported/implemented in all DB-drivers, the default is a stub method, which simply returns true.
	 *
	 * @param   boolean  $memory  Flag to control how they should be toggled.
	 *
	 * @return  boolean  True on success.
	 *
	 * @since   2.5
	 * @throws  Exception on database error.
	 */
	protected function toggleTables($memory)
	{
		if (strtolower(Factory::getDbo()->getServerType()) != 'mysql')
		{
			return true;
		}

		static $state;

		// Get the database adapter.
		$db = $this->db;

		// Check if we are setting the tables to the Memory engine.
		if ($memory === true && $state !== true)
		{
			// Set the tokens table to Memory.
			$db->setQuery('ALTER TABLE ' . $db->quoteName('#__finder_tokens') . ' ENGINE = MEMORY');
			$db->execute();

			// Set the tokens aggregate table to Memory.
			$db->setQuery('ALTER TABLE ' . $db->quoteName('#__finder_tokens_aggregate') . ' ENGINE = MEMORY');
			$db->execute();

			// Set the internal state.
			$state = $memory;
		}
		// We must be setting the tables to the InnoDB engine.
		elseif ($memory === false && $state !== false)
		{
			// Set the tokens table to InnoDB.
			$db->setQuery('ALTER TABLE ' . $db->quoteName('#__finder_tokens') . ' ENGINE = INNODB');
			$db->execute();

			// Set the tokens aggregate table to InnoDB.
			$db->setQuery('ALTER TABLE ' . $db->quoteName('#__finder_tokens_aggregate') . ' ENGINE = INNODB');
			$db->execute();

			// Set the internal state.
			$state = $memory;
		}

		return true;
	}
}