<?php
  /**
   * Copyright (c) 2013 Robin Appelman <icewind@owncloud.com>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */
  
  namespace OC\Files\Storage\Wrapper;
  
  class Quota extends Wrapper {
  
  	/**
  	 * @var int $quota
  	 */
  	protected $quota;
  
  	/**
  	 * @param array $parameters
  	 */
  	public function __construct($parameters) {
  		$this->storage = $parameters['storage'];
  		$this->quota = $parameters['quota'];
  	}
  
  	protected function getSize($path) {
  		$cache = $this->getCache();
  		$data = $cache->get($path);
  		if (is_array($data) and isset($data['size'])) {

  			if (isset($data['unencrypted_size'])
  				&& $data['unencrypted_size'] > 0
  			) {
  				return $data['unencrypted_size'];
  			}

  			return $data['size'];
  		} else {
  			return \OC\Files\SPACE_NOT_COMPUTED;
  		}
  	}
  
  	/**
  	 * Get free space as limited by the quota
  	 *
  	 * @param string $path
  	 * @return int
  	 */
  	public function free_space($path) {
  		if ($this->quota < 0) {
  			return $this->storage->free_space($path);
  		} else {
  			$used = $this->getSize('');
  			if ($used < 0) {
  				return \OC\Files\SPACE_NOT_COMPUTED;
  			} else {
  				$free = $this->storage->free_space($path);

  				$quotaFree = max($this->quota - $used, 0);
  				// if free space is known
  				if ($free >= 0) {
  					$free = min($free, $quotaFree);
  				} else {
  					$free = $quotaFree;
  				}
  				return $free;

  			}
  		}
  	}
  
  	/**
  	 * see http://php.net/manual/en/function.file_put_contents.php
  	 *
  	 * @param string $path
  	 * @param string $data
  	 * @return bool
  	 */
  	public function file_put_contents($path, $data) {
  		$free = $this->free_space('');
  		if ($free < 0 or strlen($data) < $free) {
  			return $this->storage->file_put_contents($path, $data);
  		} else {
  			return false;
  		}
  	}
  
  	/**
  	 * see http://php.net/manual/en/function.copy.php
  	 *
  	 * @param string $source
  	 * @param string $target
  	 * @return bool
  	 */
  	public function copy($source, $target) {
  		$free = $this->free_space('');
  		if ($free < 0 or $this->getSize($source) < $free) {
  			return $this->storage->copy($source, $target);
  		} else {
  			return false;
  		}
  	}
  
  	/**
  	 * see http://php.net/manual/en/function.fopen.php
  	 *
  	 * @param string $path
  	 * @param string $mode
  	 * @return resource
  	 */
  	public function fopen($path, $mode) {
  		$source = $this->storage->fopen($path, $mode);
  		$free = $this->free_space('');

  		if ($source && $free >= 0 && $mode !== 'r' && $mode !== 'rb') {

  			return \OC\Files\Stream\Quota::wrap($source, $free);
  		} else {
  			return $source;
  		}
  	}
  }