<?php

// PageRank Lookup v1.1 by HM2K (update: 31/01/07) based on an alogoritham found here: http://pagerank.gamesaga.net

// 10.30.2008 wrapped into a static class to avoid namespace conflicts by http://www.naden.de/blog

class Statbadge_Pagerank
{
  //convert a string to a 32-bit integer
  function StrToNum($Str, $Check, $Magic)
  {
      $Int32Unit = 4294967296;  // 2^32
  
      $length = strlen($Str);
      for ($i = 0; $i < $length; $i++) {
          $Check *= $Magic; 	
          //If the float is beyond the boundaries of integer (usually +/- 2.15e+9 = 2^31), 
          //  the result of converting to integer is undefined
          //  refer to http://www.php.net/manual/en/language.types.integer.php
          if ($Check >= $Int32Unit) {
              $Check = ($Check - $Int32Unit * (int) ($Check / $Int32Unit));
              //if the check less than -2^31
              $Check = ($Check < -2147483648) ? ($Check + $Int32Unit) : $Check;
          }
          $Check += ord($Str{$i}); 
      }
      return $Check;
  }
  
  //genearate a hash for a url
  function HashURL($String) {
      $Check1 = Statbadge_Pagerank::StrToNum($String, 0x1505, 0x21);
      $Check2 = Statbadge_Pagerank::StrToNum($String, 0, 0x1003F);
  
      $Check1 >>= 2; 	
      $Check1 = (($Check1 >> 4) & 0x3FFFFC0 ) | ($Check1 & 0x3F);
      $Check1 = (($Check1 >> 4) & 0x3FFC00 ) | ($Check1 & 0x3FF);
      $Check1 = (($Check1 >> 4) & 0x3C000 ) | ($Check1 & 0x3FFF);	
  	
      $T1 = (((($Check1 & 0x3C0) << 4) | ($Check1 & 0x3C)) <<2 ) | ($Check2 & 0xF0F );
      $T2 = (((($Check1 & 0xFFFFC000) << 4) | ($Check1 & 0x3C00)) << 0xA) | ($Check2 & 0xF0F0000 );
  	
      return ($T1 | $T2);
  }
  
  //genearate a checksum for the hash string
  function CheckHash($Hashnum) {
      $CheckByte = 0;
      $Flag = 0;
  
      $HashStr = sprintf('%u', $Hashnum) ;
      $length = strlen($HashStr);
  	
      for ($i = $length - 1;  $i >= 0;  $i --) {
          $Re = $HashStr{$i};
          if (1 === ($Flag % 2)) {              
              $Re += $Re;     
              $Re = (int)($Re / 10) + ($Re % 10);
          }
          $CheckByte += $Re;
          $Flag ++;	
      }
  
      $CheckByte %= 10;
      if (0 !== $CheckByte) {
          $CheckByte = 10 - $CheckByte;
          if (1 === ($Flag % 2) ) {
              if (1 === ($CheckByte % 2)) {
                  $CheckByte += 9;
              }
              $CheckByte >>= 1;
          }
      }
  
      return '7'.$CheckByte.$HashStr;
  }
  //return the pagerank figure
  function Fetch( $url )
  {
    $googlehost = 'toolbarqueries.google.com';
    $googleua = 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.6) Gecko/20060728 Firefox/1.5';
    
  	$ch = Statbadge_Pagerank::CheckHash( Statbadge_Pagerank::HashURL( $url ) );
    
  	$fp = fsockopen($googlehost, 80, $errno, $errstr, 30);
  	
    if( $fp )
    {
  	   $out = "GET /search?client=navclient-auto&ch=$ch&features=Rank&q=info:$url HTTP/1.1\r\n";
  	   $out .= "User-Agent: $googleua\r\n";
  	   $out .= "Host: $googlehost\r\n";
  	   $out .= "Connection: Close\r\n\r\n";
  	
  	   fwrite($fp, $out);
  	   
  	   //$pagerank = substr(fgets($fp, 128), 4); //debug only
  	   //echo $pagerank; //debug only
  	   while( !feof( $fp ) )
       {
  		  $data = fgets($fp, 128);
  			//echo $data;
  			$pos = strpos($data, "Rank_");
  			if($pos === false){} else{
  				$pr=substr($data, $pos + 9);
  				$pr=trim($pr);
  				$pr=str_replace("\n",'',$pr);
          return $pr;
  		  }
      }
      fclose($fp);
    }
  }
}

?>