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@wjzhangq
Created December 17, 2010 15:36
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<?php
// " MATCH($field) AGAINST('$searchon' IN BOOLEAN MODE) ";
//"SHOW GLOBAL VARIABLES LIKE 'ft\\_min\\_word\\_len'";
class normalizeText{
var $mMinSearchLength;
var $strictMatching = true;
var $searchTerms = array();
var $ignorecase = true;
function __construct($mMinSearchLength=4,$ignorecase=true){
$this->mMinSearchLength = 4;
$this->ignorecase = $ignorecase;
}
function normalize($str){
//word segmentation
$out = $this->wordSegmentation($str);
// MySQL fulltext index doesn't grok utf-8, so we
// need to fold cases and convert to hex
$out = preg_replace_callback(
"/([\\xc0-\\xff][\\x80-\\xbf]*)/",
array($this, 'stripForSearchCallback' ),
$this->lc($out));
// And to add insult to injury, the default indexing
// ignores short words... Pad them so we can pass them
// through without reconfiguring the server...
$minLength = $this->minSearchLength();
if( $minLength > 1 ) {
$n = $minLength - 1;
$out = preg_replace(
"/\b(\w{1,$n})\b/",
"$1u800",
$out );
}
// Periods within things like hostnames and IP addresses
// are also important -- we want a search for "example.com"
// or "192.168.1.1" to work sanely.
//
// MySQL's search seems to ignore them, so you'd match on
// "example.wikipedia.com" and "192.168.83.1" as well.
$out = preg_replace(
"/(\w)\.(\w|\*)/u",
"$1u82e$2",
$out );
return $out;
}
function decode($str){
$ret = array();
$tmp = explode(' ', $str);
foreach($tmp as $k=>$v){
if (strncmp($v, 'u8', 2) == 0){
$v = substr($v, 2);
$seq = array_map(array($this, 'hexChr'), str_split($v,2));
$ret[] = implode('', $seq);
}else{
$v_len = strlen($v);
if ($v_len > 8 && strpos($v, 'u82e') !== false){
$out = preg_replace("/(\w)u82e(\w|\*)/u", "$1.$2", $v);
if (strpos($out, 'u800') !== false){
$out = preg_replace('/u800([\s|\n]*)/', "$1", $out);
}
}else if($v_len >4 && $v[$v_len -4] == 'u' && $v[$v_len -3] == '8' && $v[$v_len -2] == '0' && $v[$v_len -1] == '0')
$out = substr($v, 0, $v_len -4);
else{
$out = $v;
}
$ret[] = $out;
}
}
return implode('', $ret);
}
/**
* Parse the user's query and transform it into an SQL fragment which will
* become part of a WHERE clause
*/
function parseQuery( $filteredText) {
$lc = $this->legalSearchChars(); // Minus format chars
$searchon = '';
$this->searchTerms = array();
# FIXME: This doesn't handle parenthetical expressions.
$m = array();
if( preg_match_all( '/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
$filteredText, $m, PREG_SET_ORDER ) ) {
foreach( $m as $bits ) {
@list( /* all */, $modifier, $term, $nonQuoted, $wildcard ) = $bits;
if( $nonQuoted != '' ) {
$term = $nonQuoted;
$quote = '';
} else {
$term = str_replace( '"', '', $term );
$quote = '"';
}
if( $searchon !== '' ) $searchon .= ' ';
if( $this->strictMatching && ($modifier == '') ) {
// If we leave this out, boolean op defaults to OR which is rarely helpful.
$modifier = '+';
}
// Some languages such as Serbian store the input form in the search index,
// so we may need to search for matches in multiple writing system variants.
$convertedVariants = $term;
if( is_array( $convertedVariants ) ) {
$variants = array_unique( array_values( $convertedVariants ) );
} else {
$variants = array( $term );
}
// The low-level search index does some processing on input to work
// around problems with minimum lengths and encoding in MySQL's
// fulltext engine.
// For Chinese this also inserts spaces between adjacent Han characters.
$strippedVariants = $variants;
// Some languages such as Chinese force all variants to a canonical
// form when stripping to the low-level search index, so to be sure
// let's check our variants list for unique items after stripping.
$strippedVariants = array_unique( $strippedVariants );
$searchon .= $modifier;
if( count( $strippedVariants) > 1 )
$searchon .= '(';
foreach( $strippedVariants as $stripped ) {
$stripped = $this->normalize( $stripped );
if( $nonQuoted && strpos( $stripped, ' ' ) !== false ) {
// Hack for Chinese: we need to toss in quotes for
// multiple-character phrases since normalizeForSearch()
// added spaces between them to make word breaks.
$stripped = '"' . trim( $stripped ) . '"';
}
$searchon .= "$quote$stripped$quote$wildcard ";
}
if( count( $strippedVariants) > 1 )
$searchon .= ')';
// Match individual terms or quoted phrase in result highlighting...
// Note that variants will be introduced in a later stage for highlighting!
$regexp = $this->regexTerm( $term, $wildcard );
$this->searchTerms[] = $regexp;
}
wfDebug( __METHOD__ . ": Would search with '$searchon'\n" );
wfDebug( __METHOD__ . ': Match with /' . implode( '|', $this->searchTerms ) . "/\n" );
} else {
wfDebug( __METHOD__ . ": Can't understand search query '{$filteredText}'\n" );
}
$searchon = addslashes( $searchon );
return $searchon;
}
/**
* Eventually this should be a word segmentation;
* for now just treat each character as a word.
* @todo Fixme: only do this for Han characters...
*/
function wordSegmentation( $string ) {
$reg = "/([\\xc0-\\xff][\\x80-\\xbf]*)/";
$s = self::insertSpace( $string, $reg );
return $s;
}
function lc($str){
return $this->ignorecase ? strtolower($str) : $str;
}
/**
* Armor a case-folded UTF-8 string to get through MySQL's
* fulltext search without being mucked up by funny charset
* settings or anything else of the sort.
*/
protected function stripForSearchCallback( $matches ) {
return 'u8' . bin2hex( $matches[1] );
}
/**
* Check MySQL server's ft_min_word_len setting so we know
* if we need to pad short words...
*
* @return int
*/
protected function minSearchLength() {
if( is_null( $this->mMinSearchLength ) ) {
$sql = "SHOW GLOBAL VARIABLES LIKE 'ft\\_min\\_word\\_len'";
$this->mMinSearchLength = 0;
}
return $this->mMinSearchLength;
}
protected static function insertSpace( $string, $pattern ) {
$string = preg_replace( $pattern, " $1 ", $string );
$string = preg_replace( '/ +/', ' ', $string );
return $string;
}
public static function legalSearchChars() {
return "A-Za-z_'.0-9\\x80-\\xFF\\-";
}
function regexTerm( $string, $wildcard ) {
$regex = preg_quote( $string, '/' );
return $regex;
}
function hexChr($str){
return chr(hexdec($str));
}
}
function wfDebug($str){
//echo $str;
}
if (count(explode($_SERVER['SCRIPT_FILENAME'], __FILE__)) > 1){
//没有被包含
$nt = new normalizeText(4,false);
echo "start encode\n";
$encode = $nt->normalize('写代码需谋定而后动,没有想清楚绝对不动手,10.10.2.1测试ip地址');
echo $encode, "\n";
echo "gen sql:\n";
$searchon = $nt->parseQuery('绝对不');
$sql = "SELECT *, MATCH(`content`) AGAINST('$searchon' IN BOOLEAN MODE) as rate from `articles` WHERE MATCH(`content`) AGAINST('$searchon' IN BOOLEAN MODE)";
echo $sql, "\n";
echo "start decode:\n";
echo $nt->decode($encode);
}
?>
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