<?php
/**
 * 防采集混淆字符串
 *
 * @version        $Id: downmix.inc.php 1 9:14 2010年7月6日Z tianya $
 * @package        DedeCMS.Libraries
 * @copyright      Copyright (c) 2007 - 2010, DesDev, Inc.
 * @license        http://help.dedecms.com/usersguide/license.html
 * @link           http://www.walseo.net
 */

/**
 *  混淆字符串内容
 *
 * @access    public
 * @param     string  $body  内容
 * @return    string
 */
if ( ! function_exists('RndString'))
{
    function RndString(&$body)
    {
        //最大间隔距离(如果在检测不到p标记的情况下，加入混淆字串的最大间隔距离)
        $maxpos = 1024;

        //font 的字体颜色
        $fontColor = "#FFFFFF";

        //div span p 标记的随机样式
        $st1 = chr(mt_rand(ord('A'),ord('Z'))).chr(mt_rand(ord('a'),ord('z'))).chr(mt_rand(ord('a'),ord('z'))).mt_rand(100,999);
        $st2 = chr(mt_rand(ord('A'),ord('Z'))).chr(mt_rand(ord('a'),ord('z'))).chr(mt_rand(ord('a'),ord('z'))).mt_rand(100,999);
        $st3 = chr(mt_rand(ord('A'),ord('Z'))).chr(mt_rand(ord('a'),ord('z'))).chr(mt_rand(ord('a'),ord('z'))).mt_rand(100,999);
        $st4 = chr(mt_rand(ord('A'),ord('Z'))).chr(mt_rand(ord('a'),ord('z'))).chr(mt_rand(ord('a'),ord('z'))).mt_rand(100,999);
        $rndstyle[1]['value'] = ".{$st1} { display:none; }";
        $rndstyle[1]['name'] = $st1;
        $rndstyle[2]['value'] = ".{$st2} { display:none; }";
        $rndstyle[2]['name'] = $st2;
        $rndstyle[3]['value'] = ".{$st3} { display:none; }";
        $rndstyle[3]['name'] = $st3;
        $rndstyle[4]['value'] = ".{$st4} { display:none; }";
        $rndstyle[4]['name'] = $st4;
        $mdd = mt_rand(1,4);
        $rndstyleValue = $rndstyle[$mdd]['value'];
        $rndstyleName = $rndstyle[$mdd]['name'];
        $reString = "<style> $rndstyleValue </style>\r\n";

        //附机标记
        $rndem[1] = 'font';
        $rndem[2] = 'div';
        $rndem[3] = 'span';
        $rndem[4] = 'p';

        //读取字符串数据
        $fp = fopen(DEDEDATA.'/downmix.data.php','r');
        $start = 0;
        $totalitem = 0;

        while(!feof($fp))
        {
            $v = trim(fgets($fp,128));
            if($start==1)
            {
                if(preg_match("/#end#/i", $v))
                {
                    break;
                }
                if($v!='')
                {
                    $totalitem++; $rndstring[$totalitem] = preg_replace("/#,/", "", $v);
                }
            }
            if(preg_match("/#start#/i", $v))
            {
                $start = 1;
            }
        }
        fclose($fp);

        //处理要防采集的字段
        $bodylen = strlen($body) - 1;
        $prepos = 0;
        for($i=0;$i<=$bodylen;$i++)
        {
            if($i+2 >= $bodylen || $i<50)
            {
                $reString .= $body[$i];
            }
            else
            {
                $ntag = @strtolower($body[$i].$body[$i+1].$body[$i+2]);
                if($ntag=='</p' || ($ntag=='<br' && $i-$prepos>$maxpos) )
                {
                    $dd = mt_rand(1,4);
                    $emname = $rndem[$dd];
                    $dd = mt_rand(1,$totalitem);
                    $rnstr = $rndstring[$dd];
                    if($emname!='font')
                    {
                        $rnstr = " <$emname class='$rndstyleName'>$rnstr</$emname> ";
                    }
                    else
                    {
                        $rnstr = " <font color='$fontColor'>$rnstr</font> ";
                    }
                    $reString .= $rnstr.$body[$i];
                    $prepos = $i;
                }
                else
                {
                    $reString .= $body[$i];
                }
            }
        }
        return $reString;
    }//函数结束
}
