<?php

/**

*

* +------------------------------------------------

* 敏感詞過濾類

* +------------------------------------------------

* @author gaosongwang <songwanggao@gmail.com>

* +-------------------------------------------------

* @version 2016/6/3

* +-------------------------------------------------

*/

namespace Addcn\Model\Tools\Filter;

use Addcn\Core\Library\Cache;

class TextFilter{

public $path;

private $sensitive = array();

private $sensitiveDic = null;

// private $readType = 'file';

public function __construct($configPath){

$this->path = $configPath;

}

public function read(){

if(is_readable($this->path)){

$this->sensitive = file_get_contents(

$this->path,

false,

stream_context_create(array(

'http' => array(

'header' => array('timeout'=>20)

),

'https' => array(

'header' => array('timeout' => 20)

),

))

);

}else{

die('Dic file access deny!');

}

}

/**

*

* 敏感詞字典創建

*/

public function sensitiveWordDic(){

$key = __CLASS__.":".__METHOD__.'filter';

if( $sesitive = \cache::get($key) ) return $sesitive;

$sesitive = $this->createSensitiveWordDic();

//set cache

\cache::set($key, $sesitive, 3600*3);

return $sesitive;

}

public static function clearCache(){

$key = __CLASS__.":".__METHOD__.'filter';

return \cache::delete($key);

}

/**

*

* 文本搜索

* @param unknown_type $content

* @param unknown_type $encoding

*/

public function sensitiveWordSearch($content, $encoding = 'utf-8'){

$conlen = mb_strlen($content, $encoding);

$sessitiveWord = new \ArrayObject(array());

//get dic config;

$hashMap = $this->sensitiveWordDic();

for($j=0; $j < $conlen; $j++){

$word = strtolower(mb_substr($content, $j, 1, $encoding));

//escape word;

if(empty($word) || $this->isEscapeWord($word, $encoding)){

continue;

}

$nowNode = $hashMap->offsetGet($word);

if( !$nowNode instanceof \ArrayObject ){

continue;

}

$end = $j+1;

while ($end < $conlen){

$newword = strtolower(mb_substr($content, $end, 1, $encoding));

//escape new word;

if(empty($newword) || $this->isEscapeWord($newword, $encoding)){

$end++;

continue;

}

if( $nowNode->offsetGet('isEnd') == 1){

$sword = mb_substr($content,$j,$end-$j, $encoding);

$swordNum = $sessitiveWord->offsetGet($sword);

$sessitiveWord->offsetSet($sword, ($swordNum ? $swordNum : 0)+1);

}

$nextNode = $nowNode->offsetGet($newword);

if(!$nextNode instanceof \ArrayObject) break;

$nowNode = $nextNode;

$end++;

}

}

return $sessitiveWord->getArrayCopy();

}

/**

*

* 字典創建

* @param unknown_type $encoding

* @throws \RuntimeException

*/

public function createSensitiveWordDic($encoding = 'utf-8'){

$this->read();

if( empty($this->sensitive) ) throw new \RuntimeException('敏感詞表為空！');

$hashMap = new \ArrayObject(array());

$strArr = explode(',', $this->sensitive);

foreach ($strArr as $k=>$v){

$v = trim($v);

$len = mb_strlen($v,$encoding);

$nowMap = $hashMap;

for ($i=0; $i<$len; $i++){

$word = mb_substr(trim($v), $i, 1, $encoding);

if( empty($word) || $this->isEscapeWord($word) ) continue;

if( !$nowMap instanceof \ArrayObject) continue;

$wordMap = $nowMap->offsetGet($word);

if($wordMap){

$nowMap = $wordMap;

}else{

$newMap = new \ArrayObject(array());

$newMap -> offsetSet('isEnd',0);

$nowMap->offsetSet(strtolower($word), $newMap);

$nowMap = $newMap;

}

if($i == $len-1){

$nowMap->offsetSet('isEnd', 1);

}

}

}

return $hashMap;

}

public function escapeWord($content , $encoding = 'utf-8'){

$conlen = mb_strlen($content, $encoding);

$n = '';

for($j=0; $j < $conlen; $j++){

$word = mb_substr($content, $j, 1, $encoding);

if( empty($word) || $this->isEscapeWord($word, $encoding)) continue;

$n .= $word;

}

return $n;

}

/**

*

* 特殊文本過濾

* @param unknown_type $word

* @param unknown_type $encoding

* return boolean

* a-z ={97,122},

* A-Z ={65,90}

* 1-9 ={49,57}

* @ = {64}

* word ={19968,40869}

*/

public function isEscapeWord($word, $encoding = 'utf-8'){

$unicode = Unicode::charCodeAt($word, $encoding);

switch (true){

case $unicode >= 97 && $unicode <= 122 :

return false;

break;

case $unicode >=65 && $unicode <= 90 :

return false;

break;

case $unicode >=19968 && $unicode <=40869 :

return false;

break;

case $unicode == 64:

return false;

break;

}

return true;

}

}