<?php

/* ===================================
* Author: Nazarkin Roman
* -----------------------------------
* Contacts:
* email - roman@nazarkin.su
* icq - 642971062
* skype - roman444ik
* -----------------------------------
* GitHub:
* https://github.com/NazarkinRoman
* ===================================
*/

class MicroCache {
  public $patch = 'cachetmp/';
  public $lifetime = 3600; // default value - 1 hour
  public $c_type = 'memcache';
  public $cache_on = true;
  public $is_cached = false;
  public $memcache_compressed = false;
  public $file, $key;
  private $memcache;

  function __construct($key=false) {

    class_exists('Memcache') or $this->c_type = 'file';

    if($this->c_type != 'file'){
      $this->memcache = new Memcache;
      @$this->memcache->connect('localhost', 11211) or $this->c_type = 'file';
    }

    $this->key = md5( $key===false ? $_SERVER["REQUEST_URI"] : $key);
    $this->file = $this->patch . $this->key . '.cache';
  }

  public function check() {
    return $this->is_cached = !$this->cache_on ? false
      : $this->c_type == 'file' ?
        ( is_readable($this->file) and is_writable($this->file) and (time()-filemtime($this->file) < $this->lifetime) )
        : $this->is_cached = ( $this->cache_on and $this->memcache->get($this->key) );
  }

  public function out() {
    return !$this->is_cached ? ''
      : $this->c_type == 'file' ?
        file_get_contents($this->file)
        : $this->memcache->get($this->key);
  }

  public function start() {
    ob_start();
  }

  public function end() {
    $buffer = ob_get_contents();
    ob_end_clean();

    $this->cache_on and $this->write($buffer);

    die ($buffer);
  }

  public function write($buffer = ''){
    if($this->c_type == 'file') {
      $fp = @fopen($this->file, 'w') or die("Cannot create cache file : {$this->file}");
      if ( @flock($fp, LOCK_EX)) {
        fwrite($fp, $buffer);
        fflush($fp);
        flock($fp, LOCK_UN);
        fclose($fp);
      }
    } else $this->memcache->set($this->key, $buffer, $this->memcache_compressed, $this->lifetime);
  }

  public function clear($key=false){
    $key = $key === false ? $this->key : md5($key);
    $file = $this->patch . $this->key . '.cache';
    if ($this->c_type == 'file') @unlink($file);
    else $this->memcache->delete($key);
  }

}