<?php
  /**
   * Copyright (c) 2012 Bart Visscher <bartv@thisnet.nl>

   * Copyright (c) 2014 Vincent Petry <pvince81@owncloud.com>

   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */

  namespace OC\Cache;

  class File {

  	protected $storage;

  
  	/**
  	 * Returns the cache storage for the logged in user
  	 * @return \OC\Files\View cache storage
  	 */

  	protected function getStorage() {
  		if (isset($this->storage)) {
  			return $this->storage;
  		}

  		if(\OC_User::isLoggedIn()) {
  			\OC\Files\Filesystem::initMountPoints(\OC_User::getUser());

  			$this->storage = new \OC\Files\View('/' . \OC_User::getUser() . '/cache');

  			return $this->storage;
  		}else{

  			\OC_Log::write('core', 'Can\'t get cache storage, user not logged in', \OC_Log::ERROR);

  			throw new \OC\ForbiddenException('Can\t get cache storage, user not logged in');

  		}
  	}

  	/**
  	 * @param string $key
  	 */

  	public function get($key) {
  		$result = null;
  		$proxyStatus = \OC_FileProxy::$enabled;
  		\OC_FileProxy::$enabled = false;
  		if ($this->hasKey($key)) {
  			$storage = $this->getStorage();
  			$result = $storage->file_get_contents($key);
  		}
  		\OC_FileProxy::$enabled = $proxyStatus;
  		return $result;
  	}
  
  	/**
  	 * Returns the size of the stored/cached data
  	 *

  	 * @param string $key

  	 * @return int
  	 */
  	public function size($key) {
  		$result = 0;
  		$proxyStatus = \OC_FileProxy::$enabled;
  		\OC_FileProxy::$enabled = false;
  		if ($this->hasKey($key)) {
  			$storage = $this->getStorage();
  			$result = $storage->filesize($key);
  		}
  		\OC_FileProxy::$enabled = $proxyStatus;
  		return $result;
  	}

  	/**
  	 * @param string $key
  	 */

  	public function set($key, $value, $ttl=0) {
  		$storage = $this->getStorage();
  		$result = false;
  		$proxyStatus = \OC_FileProxy::$enabled;
  		\OC_FileProxy::$enabled = false;
  		if ($storage and $storage->file_put_contents($key, $value)) {
  			if ($ttl === 0) {
  				$ttl = 86400; // 60*60*24
  			}
  			$result = $storage->touch($key, time() + $ttl);
  		}
  		\OC_FileProxy::$enabled = $proxyStatus;
  		return $result;
  	}
  
  	public function hasKey($key) {
  		$storage = $this->getStorage();
  		if ($storage && $storage->is_file($key)) {

  			return true;
  		}
  		return false;
  	}

  	/**
  	 * @param string $key
  	 */

  	public function remove($key) {
  		$storage = $this->getStorage();
  		if(!$storage) {
  			return false;
  		}
  		return $storage->unlink($key);
  	}
  
  	public function clear($prefix='') {
  		$storage = $this->getStorage();
  		if($storage and $storage->is_dir('/')) {
  			$dh=$storage->opendir('/');
  			if(is_resource($dh)) {
  				while (($file = readdir($dh)) !== false) {
  					if($file!='.' and $file!='..' and ($prefix==='' || strpos($file, $prefix) === 0)) {
  						$storage->unlink('/'.$file);
  					}
  				}
  			}
  		}
  		return true;
  	}
  
  	public function gc() {
  		$storage = $this->getStorage();
  		if($storage and $storage->is_dir('/')) {
  			$now = time();
  			$dh=$storage->opendir('/');
  			if(!is_resource($dh)) {
  				return null;
  			}
  			while (($file = readdir($dh)) !== false) {
  				if($file!='.' and $file!='..') {
  					$mtime = $storage->filemtime('/'.$file);
  					if ($mtime < $now) {
  						$storage->unlink('/'.$file);
  					}
  				}
  			}
  		}
  	}
  
  	public static function loginListener() {
  		$c = new self();
  		$c->gc();
  	}
  }