/**
* Установить свойство 'context' документа (фрагменты совпавшего с запросом текста)
* (не имеет отношения к nc_search_context)
*/
protected function document_set_context(nc_search_result_document $doc)
{
// служба поиска (напр. Гугль какой-нибудь), теоретически, может установить свойство context
if (!$doc->get('context') && $this->should_highlight()) {
$language = $this->get_query()->get('language');
$doc->set('context', $this->highlight($doc->get('content'), $language, nc_search::get_setting('ResultContextMaxNumberOfWords')));
$doc->set('title', $this->highlight($doc->get('title'), $language, nc_search::get_setting('ResultTitleMaxNumberOfWords')));
}
return $doc;
}
/**
* Выполнение запроса
* @param nc_search_query $query
* @param boolean $should_highlight
* @return nc_search_result
*/
public function find(nc_search_query $query, $should_highlight = true)
{
$db = $this->get_db();
$id_list = "0";
$translator = new nc_search_provider_index_translator($this);
// get IDs
$select_ids_query = $query->translate($translator);
$limit = (int) $query->get('limit');
$offset = (int) $query->get('offset');
$total_hits_unknown = false;
if ($select_ids_query) {
// neither null nor empty string
$db->last_error = null;
if (is_array($select_ids_query)) {
// will need to create a temporary table; no final row count
$prefilter_query = $select_ids_query["prefilter"];
$refinement_query = $select_ids_query["refinement"];
$query_hash = sha1($prefilter_query);
// (1) create temporary table
$db->query("SET @rank=0");
$db->query("CREATE TEMPORARY TABLE `{$select_ids_query['temp_table']}` " . "(INDEX (`Rank`,`Document_ID`)) " . "SELECT filtered.`Document_ID`, @rank := @rank+1 AS `Rank` " . "FROM ({$prefilter_query}) AS filtered");
// (2) check for cached offset values so we won't need to check from the beginning of the pre-filtered list
$rank_table = $this->last_rank_table_name;
$db->query("DELETE FROM `{$rank_table}` WHERE `Time` < NOW() - INTERVAL {$this->rank_cache_interval}");
$cached_rank = $offset ? $db->get_row("SELECT `Offset`, `Rank` FROM `{$rank_table}`\n" . "WHERE `QueryHash` = '{$query_hash}' AND `Offset` <= {$offset}\n" . "ORDER BY `Offset` DESC\nLIMIT 1", ARRAY_A) : null;
if ($cached_rank) {
$refinement_offset = $offset - $cached_rank["Offset"];
$refinement_rank_value = $cached_rank["Rank"];
} else {
$refinement_offset = $offset;
$refinement_rank_value = 0;
}
$db->query("SET @rank_value = {$refinement_rank_value}");
// (3) select IDs
$db->query("{$refinement_query}\n" . "LIMIT " . ($limit + 1) . " OFFSET {$refinement_offset}");
$ids = $db->get_col();
$id_list = join(', ', $ids);
if (count($ids) > $limit) {
// has next page
// total result count is set to (current page + 1 page)
// so there will be a paginator
$total_hits = $offset + 2 * $limit;
$total_hits_unknown = true;
// save rank for the next page
$last_rank = $db->get_var(null, 1, $limit);
$db->query("REPLACE INTO `{$this->last_rank_table_name}`\n SET `Time` = NOW(),\n `QueryHash` = '{$query_hash}',\n `Offset` = " . ($offset + $limit) . ",\n `Rank` = {$last_rank}");
} else {
$total_hits = $offset + count($ids);
}
} else {
// select IDs in a single query
$id_list = join(', ', $db->get_col($select_ids_query));
$total_hits = $db->last_error ? 0 : $db->get_var("SELECT FOUND_ROWS()");
}
} else {
// Translator thinks there won't be any results (terms in the query are not in the index)
// we could get $translator->get_unknown_terms(), but it is of no use for the correctors... :(
$total_hits = 0;
}
// make 'result' object
$result = new nc_search_result(array(), $total_hits);
$result->set_query($query);
/* @todo use $total_hits_unknown to mark that total count is not known */
if (!$should_highlight) {
$result->disable_highlighting();
}
if ($total_hits && $id_list) {
// get field list
$doc = new nc_search_result_document();
$fields = $doc->get_column_names($query->get('options_to_fetch'));
// get document data
$doc_query = "SELECT {$fields} FROM `%t%` WHERE `Document_ID` IN ({$id_list}) " . "ORDER BY FIELD(`Document_ID`, {$id_list}) " . "LIMIT {$limit}";
$result->select_from_database($doc_query);
}
return $result;
}
/**
* Поиск по индексу
* @param nc_search_query $query
* @param boolean $should_highlight
* @return nc_search_result
*/
public function find(nc_search_query $query, $should_highlight = true)
{
nc_search::set_current_context(new nc_search_context(array('search_provider' => get_class($this), 'action' => 'searching', 'language' => $query->get('language'))));
$index = $this->get_index();
$lucene_query = $this->get_lucene_query($query);
if ($query->get('sort_by')) {
// custom sort
$lucene_result = $index->find($lucene_query, $query->get('sort_by'), SORT_STRING, $query->get('sort_direction'));
} else {
$lucene_result = $index->find($lucene_query);
}
$total_hits = count($lucene_result);
$result = new nc_search_result(array(), $total_hits);
$result->set_query($query);
if (!$should_highlight) {
$result->disable_highlighting();
}
nc_search::set_current_context();
// truncate to get the requested page only
$lucene_result = array_slice($lucene_result, $query->get('offset'), $query->get('limit'));
// сформировать nc_search_result
$result_ids = array();
foreach ($lucene_result as $hit) {
$result_ids[] = $hit->doc_id;
}
if (count($result_ids)) {
foreach ($result_ids as $i => $id) {
$result_ids[$i] = (int) trim($id, "x");
}
$id_list = join(", ", $result_ids);
$doc = new nc_search_result_document();
$fields = $doc->get_column_names($query->get('options_to_fetch'));
$query = "SELECT {$fields} FROM `%t%` WHERE `Document_ID` IN ({$id_list}) " . "ORDER BY FIELD(`Document_ID`, {$id_list})";
$result->select_from_database($query);
}
return $result;
}