<?php
  /**
   * Copyright (c) 2012 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\Cache;
  
  class Permissions {
  	/**
  	 * @var string $storageId
  	 */
  	private $storageId;
  
  	/**
  	 * @param \OC\Files\Storage\Storage|string $storage
  	 */
  	public function __construct($storage) {
  		if ($storage instanceof \OC\Files\Storage\Storage) {
  			$this->storageId = $storage->getId();
  		} else {
  			$this->storageId = $storage;
  		}
  	}
  
  	/**
  	 * get the permissions for a single file
  	 *
  	 * @param int $fileId
  	 * @param string $user
  	 * @return int (-1 if file no permissions set)
  	 */
  	public function get($fileId, $user) {

  		$sql = 'SELECT `permissions` FROM `*PREFIX*permissions` WHERE `user` = ? AND `fileid` = ?';
  		$result = \OC_DB::executeAudited($sql, array($user, $fileId));

  		if ($row = $result->fetchRow()) {
  			return $row['permissions'];
  		} else {
  			return -1;
  		}
  	}
  
  	/**
  	 * set the permissions of a file
  	 *
  	 * @param int $fileId
  	 * @param string $user
  	 * @param int $permissions
  	 */
  	public function set($fileId, $user, $permissions) {
  		if (self::get($fileId, $user) !== -1) {

  			$sql = 'UPDATE `*PREFIX*permissions` SET `permissions` = ? WHERE `user` = ? AND `fileid` = ?';

  		} else {

  			$sql = 'INSERT INTO `*PREFIX*permissions`(`permissions`, `user`, `fileid`) VALUES(?, ?,? )';

  		}

  		\OC_DB::executeAudited($sql, array($permissions, $user, $fileId));

  	}
  
  	/**
  	 * get the permissions of multiply files
  	 *
  	 * @param int[] $fileIds
  	 * @param string $user
  	 * @return int[]
  	 */
  	public function getMultiple($fileIds, $user) {
  		if (count($fileIds) === 0) {
  			return array();
  		}
  		$params = $fileIds;
  		$params[] = $user;
  		$inPart = implode(', ', array_fill(0, count($fileIds), '?'));

  		$sql = 'SELECT `fileid`, `permissions` FROM `*PREFIX*permissions`'
  			. ' WHERE `fileid` IN (' . $inPart . ') AND `user` = ?';
  		$result = \OC_DB::executeAudited($sql, $params);

  		$filePermissions = array();
  		while ($row = $result->fetchRow()) {
  			$filePermissions[$row['fileid']] = $row['permissions'];
  		}
  		return $filePermissions;
  	}
  
  	/**
  	 * get the permissions for all files in a folder
  	 *
  	 * @param int $parentId
  	 * @param string $user
  	 * @return int[]
  	 */
  	public function getDirectoryPermissions($parentId, $user) {

  		$sql = 'SELECT `*PREFIX*permissions`.`fileid`, `permissions`
  			FROM `*PREFIX*permissions`
  			INNER JOIN `*PREFIX*filecache` ON `*PREFIX*permissions`.`fileid` = `*PREFIX*filecache`.`fileid`
  			WHERE `*PREFIX*filecache`.`parent` = ? AND `*PREFIX*permissions`.`user` = ?';

  		$result = \OC_DB::executeAudited($sql, array($parentId, $user));

  		$filePermissions = array();
  		while ($row = $result->fetchRow()) {
  			$filePermissions[$row['fileid']] = $row['permissions'];
  		}
  		return $filePermissions;
  	}
  
  	/**
  	 * remove the permissions for a file
  	 *
  	 * @param int $fileId
  	 * @param string $user
  	 */
  	public function remove($fileId, $user = null) {
  		if (is_null($user)) {

  			\OC_DB::executeAudited('DELETE FROM `*PREFIX*permissions` WHERE `fileid` = ?', array($fileId));

  		} else {

  			$sql = 'DELETE FROM `*PREFIX*permissions` WHERE `fileid` = ? AND `user` = ?';
  			\OC_DB::executeAudited($sql, array($fileId, $user));

  		}
  	}
  
  	public function removeMultiple($fileIds, $user) {
  		$query = \OC_DB::prepare('DELETE FROM `*PREFIX*permissions` WHERE `fileid` = ? AND `user` = ?');
  		foreach ($fileIds as $fileId) {

  			\OC_DB::executeAudited($query, array($fileId, $user));

  		}
  	}

  
  	/**
  	 * get the list of users which have permissions stored for a file
  	 *
  	 * @param int $fileId
  	 */
  	public function getUsers($fileId) {
  		$sql = 'SELECT `user` FROM `*PREFIX*permissions` WHERE `fileid` = ?';
  		$result = \OC_DB::executeAudited($sql, array($fileId));
  		$users = array();
  		while ($row = $result->fetchRow()) {
  			$users[] = $row['user'];
  		}
  		return $users;
  	}

  }