wiki.techinc.nl/includes/SearchEngine.php
Ævar Arnfjörð Bjarmason 6c5d3c8c6a * Adding a trailing ?>
2006-03-07 13:32:27 +00:00

347 lines
7.3 KiB
PHP

<?php
/**
* Contain a class for special pages
* @package MediaWiki
* @subpackage Search
*/
/**
* @package MediaWiki
*/
class SearchEngine {
var $limit = 10;
var $offset = 0;
var $searchTerms = array();
var $namespaces = array( NS_MAIN );
var $showRedirects = false;
/**
* Perform a full text search query and return a result set.
* If title searches are not supported or disabled, return null.
*
* @param string $term - Raw search term
* @return SearchResultSet
* @access public
* @abstract
*/
function searchText( $term ) {
return null;
}
/**
* Perform a title-only search query and return a result set.
* If title searches are not supported or disabled, return null.
*
* @param string $term - Raw search term
* @return SearchResultSet
* @access public
* @abstract
*/
function searchTitle( $term ) {
return null;
}
/**
* If an exact title match can be find, or a very slightly close match,
* return the title. If no match, returns NULL.
*
* @static
* @param string $term
* @return Title
* @access private
*/
function getNearMatch( $term ) {
# Exact match? No need to look further.
$title = Title::newFromText( $term );
if (is_null($title))
return NULL;
if ( $title->getNamespace() == NS_SPECIAL || $title->exists() ) {
return $title;
}
# Now try all lower case (i.e. first letter capitalized)
#
$title = Title::newFromText( strtolower( $term ) );
if ( $title->exists() ) {
return $title;
}
# Now try capitalized string
#
$title = Title::newFromText( ucwords( strtolower( $term ) ) );
if ( $title->exists() ) {
return $title;
}
# Now try all upper case
#
$title = Title::newFromText( strtoupper( $term ) );
if ( $title->exists() ) {
return $title;
}
# Now try Word-Caps-Breaking-At-Word-Breaks, for hyphenated names etc
$title = Title::newFromText( preg_replace_callback(
'/\b([\w\x80-\xff]+)\b/',
create_function( '$matches', '
global $wgContLang;
return $wgContLang->ucfirst($matches[1]);
' ),
$term ) );
if ( $title->exists() ) {
return $title;
}
global $wgCapitalLinks, $wgContLang;
if( !$wgCapitalLinks ) {
// Catch differs-by-first-letter-case-only
$title = Title::newFromText( $wgContLang->ucfirst( $term ) );
if ( $title->exists() ) {
return $title;
}
$title = Title::newFromText( $wgContLang->lcfirst( $term ) );
if ( $title->exists() ) {
return $title;
}
}
$title = Title::newFromText( $term );
# Entering an IP address goes to the contributions page
if ( ( $title->getNamespace() == NS_USER && User::isIP($title->getText() ) )
|| User::isIP( trim( $term ) ) ) {
return Title::makeTitle( NS_SPECIAL, "Contributions/" . $title->getDbkey() );
}
# Entering a user goes to the user page whether it's there or not
if ( $title->getNamespace() == NS_USER ) {
return $title;
}
# Quoted term? Try without the quotes...
if( preg_match( '/^"([^"]+)"$/', $term, $matches ) ) {
return SearchEngine::getNearMatch( $matches[1] );
}
return NULL;
}
function legalSearchChars() {
return "A-Za-z_'0-9\\x80-\\xFF\\-";
}
/**
* Set the maximum number of results to return
* and how many to skip before returning the first.
*
* @param int $limit
* @param int $offset
* @access public
*/
function setLimitOffset( $limit, $offset = 0 ) {
$this->limit = intval( $limit );
$this->offset = intval( $offset );
}
/**
* Set which namespaces the search should include.
* Give an array of namespace index numbers.
*
* @param array $namespaces
* @access public
*/
function setNamespaces( $namespaces ) {
$this->namespaces = $namespaces;
}
/**
* Make a list of searchable namespaces and their canonical names.
* @return array
* @access public
*/
function searchableNamespaces() {
global $wgContLang;
$arr = array();
foreach( $wgContLang->getNamespaces() as $ns => $name ) {
if( $ns >= NS_MAIN ) {
$arr[$ns] = $name;
}
}
return $arr;
}
/**
* Return a 'cleaned up' search string
*
* @return string
* @access public
*/
function filter( $text ) {
$lc = $this->legalSearchChars();
return trim( preg_replace( "/[^{$lc}]/", " ", $text ) );
}
/**
* Load up the appropriate search engine class for the currently
* active database backend, and return a configured instance.
*
* @return SearchEngine
* @access private
*/
function create() {
global $wgDBtype, $wgSearchType;
if( $wgSearchType ) {
$class = $wgSearchType;
} elseif( $wgDBtype == 'mysql' ) {
$class = 'SearchMySQL4';
require_once( 'SearchMySQL4.php' );
} else if ( $wgDBtype == 'PostgreSQL' ) {
$class = 'SearchTsearch2';
require_once( 'SearchTsearch2.php' );
} else {
$class = 'SearchEngineDummy';
}
$search = new $class( wfGetDB( DB_SLAVE ) );
$search->setLimitOffset(0,0);
return $search;
}
/**
* Create or update the search index record for the given page.
* Title and text should be pre-processed.
*
* @param int $id
* @param string $title
* @param string $text
* @abstract
*/
function update( $id, $title, $text ) {
// no-op
}
/**
* Update a search index record's title only.
* Title should be pre-processed.
*
* @param int $id
* @param string $title
* @abstract
*/
function updateTitle( $id, $title ) {
// no-op
}
}
/** @package MediaWiki */
class SearchResultSet {
/**
* Fetch an array of regular expression fragments for matching
* the search terms as parsed by this engine in a text extract.
*
* @return array
* @access public
* @abstract
*/
function termMatches() {
return array();
}
function numRows() {
return 0;
}
/**
* Return true if results are included in this result set.
* @return bool
* @abstract
*/
function hasResults() {
return false;
}
/**
* Some search modes return a total hit count for the query
* in the entire article database. This may include pages
* in namespaces that would not be matched on the given
* settings.
*
* Return null if no total hits number is supported.
*
* @return int
* @access public
*/
function getTotalHits() {
return null;
}
/**
* Some search modes return a suggested alternate term if there are
* no exact hits. Returns true if there is one on this set.
*
* @return bool
* @access public
*/
function hasSuggestion() {
return false;
}
/**
* Some search modes return a suggested alternate term if there are
* no exact hits. Check hasSuggestion() first.
*
* @return string
* @access public
*/
function getSuggestion() {
return '';
}
/**
* Fetches next search result, or false.
* @return SearchResult
* @access public
* @abstract
*/
function next() {
return false;
}
}
/** @package MediaWiki */
class SearchResult {
function SearchResult( $row ) {
$this->mTitle = Title::makeTitle( $row->page_namespace, $row->page_title );
}
/**
* @return Title
* @access public
*/
function getTitle() {
return $this->mTitle;
}
/**
* @return double or null if not supported
*/
function getScore() {
return null;
}
}
/**
* @package MediaWiki
*/
class SearchEngineDummy {
function search( $term ) {
return null;
}
function setLimitOffset($l, $o) {}
function legalSearchChars() {}
function update() {}
function setnamespaces() {}
function searchtitle() {}
function searchtext() {}
}
?>