<?php

class dataArchive
{

  private $savePath = "/tmp/session/";
  private $timeLife = 604800;  
  private $sid;

  static private $gc = 0;

  private function generate() {
    // методо генерирует случайную строку

    $chars = 'abdefhiknrstyzABDEFGHKNQRSTYZ23456789';
    $numChars = strlen($chars);
    $string = '';

    for ($i = 0; $i < 32; $i++)
      $string .= substr($chars, rand(1, $numChars) - 1, 1);

    $this->sid = $string;
  }
 
  public function __construct() {
    // конструктор класса
    
    $this->timeLife = $timeLife;
    $this->size = $size;
    self::$gc++;

    $cookie = $_COOKIE['sid'];

    if(isset($cookie))
      $this->sid = $cookie;

    else {
      $this->generate();
      setcookie('sid', $this->sid, time()+604800);
    }

    if(self::$gc >= 1500)
      $this->gc();
  }
 
  public function get($key = 'all') {
    
    $fh = fopen($this->savePath . $this->sid, "r");  
    $data = fgets($fh); 
    fclose($fh);
  
    $data = json_decode($data, true);   

    if($key == 'all')
      return $data;
    else
      return $data[$key];
  
}
 
  public function set($arr) {
    $path = $this->savePath . $this->sid;
    
    $fh = fopen($path, "a+");

    if(filesize($path) > 0)      
    {
      $data = fgets($fh);
      $data = json_decode($data, true);
      
      ftruncate($fh, 0);
      fputs($fh, json_encode(array_merge($data, $arr)));
    }
    else
      fputs($fh, json_encode($arr));

    fclose($fh);
  }
 
  public function destroy($id) {
    unlink($this->savePath . $this.sid);
  }
 
  private function gc() {
    self::$gc = 0;

    $dh = opendir($this->savePath);
    while(($file = readdir($dh)) !== false) {
      if(time() - filemtime($file) >= $this->timeLife && is_file($this->savePath . $file))      
        unlink($this->savePath . $file);
    }
  }
}