<?php
  
  /**
   * This plugin check user quota and deny creating files when they exceeds the quota.
   *
   * @author Sergio Cambra
   * @copyright Copyright (C) 2012 entreCables S.L. All rights reserved.
   * @license http://code.google.com/p/sabredav/wiki/License Modified BSD License
   */
  class OC_Connector_Sabre_QuotaPlugin extends Sabre_DAV_ServerPlugin {
  
  	/**
  	 * Reference to main server object
  	 *
  	 * @var Sabre_DAV_Server
  	 */
  	private $server;
  
  	/**
  	 * is kept public to allow overwrite for unit testing
  	 *
  	 * @var \OC\Files\View
  	 */
  	public $fileView;
  
  	/**
  	 * This initializes the plugin.
  	 *
  	 * This function is called by Sabre_DAV_Server, after
  	 * addPlugin is called.
  	 *
  	 * This method should set up the requires event subscriptions.
  	 *
  	 * @param Sabre_DAV_Server $server
  	 * @return void
  	 */
  	public function initialize(Sabre_DAV_Server $server) {
  
  		$this->server = $server;
  
  		$server->subscribeEvent('beforeWriteContent', array($this, 'checkQuota'), 10);
  		$server->subscribeEvent('beforeCreateFile', array($this, 'checkQuota'), 10);
  	}
  
  	/**
  	 * This method is called before any HTTP method and validates there is enough free space to store the file
  	 *
  	 * @param string $method
  	 * @throws Sabre_DAV_Exception
  	 * @return bool
  	 */
  	public function checkQuota($uri, $data = null) {
  		$length = $this->getLength();
  		if ($length) {
  			if (substr($uri, 0, 1)!=='/') {
  				$uri='/'.$uri;
  			}
  			list($parentUri, $newName) = Sabre_DAV_URLUtil::splitPath($uri);

  			$req = $this->server->httpRequest;
  			if ($req->getHeader('OC-Chunked')) {
  				$info = OC_FileChunking::decodeName($newName);
  				$chunkHandler = new OC_FileChunking($info);
  				// substract the already uploaded size to see whether
  				// there is still enough space for the remaining chunks
  				$length -= $chunkHandler->getCurrentSize();
  			}

  			$freeSpace = $this->getFreeSpace($parentUri);

  			if ($freeSpace !== \OC\Files\SPACE_UNKNOWN && $length > $freeSpace) {

  				if (isset($chunkHandler)) {
  					$chunkHandler->cleanup();
  				}

  				throw new Sabre_DAV_Exception_InsufficientStorage();
  			}
  		}
  		return true;
  	}
  
  	public function getLength()
  	{
  		$req = $this->server->httpRequest;
  		$length = $req->getHeader('X-Expected-Entity-Length');
  		if (!$length) {
  			$length = $req->getHeader('Content-Length');
  		}
  
  		$ocLength = $req->getHeader('OC-Total-Length');
  		if ($length && $ocLength) {
  			return max($length, $ocLength);
  		}
  
  		return $length;
  	}
  
  	/**
  	 * @param $parentUri
  	 * @return mixed
  	 */
  	public function getFreeSpace($parentUri)
  	{
  		if (is_null($this->fileView)) {
  			// initialize fileView
  			$this->fileView = \OC\Files\Filesystem::getView();
  		}
  
  		$freeSpace = $this->fileView->free_space($parentUri);
  		return $freeSpace;
  	}
  }