Uplink/Numerics.class.php

   1 <?php
   2 /********************************* PHP-P10 ******************************
   3  *    P10 uplink class by pk910   (c)2011 pk910                         *
   4  ************************************************************************
   5  *                          Version 2 (OOP)                             *
   6  *                                                                      *
   7  * PHP-P10 is free software; you can redistribute it and/or modify      *
   8  * it under the terms of the GNU General Public License as published by *
   9  * the Free Software Foundation; either version 2 of the License, or    *
  10  * (at your option) any later version.                                  *
  11  *                                                                      *
  12  * This program is distributed in the hope that it will be useful,      *
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of       *
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
  15  * GNU General Public License for more details.                         *
  16  *                                                                      *
  17  * You should have received a copy of the GNU General Public License    *
  18  * along with PHP-P10; if not, write to the Free Software Foundation,   *
  19  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.       *
  20  *                                                                      *
  21  ************************************************************************
  22  *
  23  *  Uplink/Numerics.class.php
  24  *
  25  * P10 numeric functions
  26  *
  27  ************************************************************************
  28  * accessable functions
  29  *
  30  * static String intToNum(int $int, int $length)
  31  *     returns the numeric representing $int
  32  *
  33  * static int numToInt(String $numeric)
  34  *     returns the integer value, the numeric represents
  35  */
  36
  37 class Numerics {
  38         private static $base64chars = array(
  39           'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P',
  40           'Q','R','S','T','U','V','W','X','Y','Z','a','b','c','d','e','f',
  41           'g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v',
  42           'w','x','y','z','0','1','2','3','4','5','6','7','8','9','[',']'
  43         );
  44         private static $base64charsLength = 64;
  45
  46         public static function intToNum($int, $length) {
  47                 //fix a small "bug": normaly 0 = AAAAA but we need 1 = AAAAA
  48                 $int = $int - 1;
  49
  50                 $numeric = "";
  51                 for($pos = $length-1; $pos >= 0; $pos--) {
  52                         //current position represents floor($int / ($base64charsLength ^ $pos))
  53                         $base = 1;
  54                         for($i = 0; $i < $pos; $i++) {
  55                                 $base = $base * self::$base64charsLength;
  56                         }
  57                         $posValue = floor($int / $base);
  58                         //get the char representing $posValue
  59                         $posChar = self::$base64chars[$posValue];
  60                         $numeric .= $posChar;
  61                 }
  62
  63                 return $numeric;
  64         }
  65
  66         public static function numToInt($numeric) {
  67                 $base = 1;
  68                 $int = 0;
  69                 for($pos = strlen($numeric)-1; $pos >= 0; $pos--) {
  70                         $posValue = array_search($numeric[$pos], self::$base64chars);
  71                         $int = ($posValue * $base);
  72                         $base = $base * self::$base64charsLength;
  73                 }
  74
  75                 //fix a small "bug": normaly 0 = AAAAA but we need 1 = AAAAA
  76                 $int = $int + 1;
  77
  78                 return $int;
  79         }
  80
  81 }
  82
  83 ?>