<?php
class BulkRename
{
  private $dirname;
  private $dh;
  
  function __construct($dirname)
  {
    $this->dirname=$dirname;
    $this->dh=opendir($this->dirname);
    if(!$this->dh)
    {
      die("Error reading defined directory {$this->dirname}.\r\n");
    }
    $this->start_rename();  
  }
  function __destruct()
  {
    if($this->dh)
    {
      closedir($this->dh);
    }
  }
  function start_rename()
  {
    $i=1;
    while(($filename=readdir($this->dh))!==false)
    { 
      $old_filename=$this->dirname."/$filename";
      if($i<10)
      {
        $index="000".$i;
      }
      if($i>=10 && $i<100)
      {
        $index="00".$i;
      }
      if($i>=100 && $i<1000)
      {
        $index="0".$i;
      }
      $new_filename=$this->dirname."/$index.jpg";  
      
      if(!is_file($old_filename))
      {
        continue;
      }
      system('mv "'.$old_filename.'" '.$new_filename);
      print 'mv "'.$old_filename.'" '.$new_filename."\r\n";
      $i++;
    }   
  }
}
$br=new BulkRename($argv[1]);
?