<?php
  /**
   * Copyright (c) 2014 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 OCA\Files_Sharing;
  
  use OC\Files\Mount\Mount;
  use OC\Files\Mount\MoveableMount;
  
  /**
   * Shared mount points can be moved by the user
   */
  class SharedMount extends Mount implements MoveableMount {
  	/**
  	 * @var \OC\Files\Storage\Shared $storage
  	 */
  	protected $storage = null;
  
  	public function __construct($storage, $mountpoint, $arguments = null, $loader = null) {
  		// first update the mount point before creating the parent
  		$newMountPoint = self::verifyMountPoint($arguments['share']);
  		$absMountPoint = '/' . \OCP\User::getUser() . '/files' . $newMountPoint;
  		parent::__construct($storage, $absMountPoint, $arguments, $loader);
  	}
  
  	/**
  	 * check if the parent folder exists otherwise move the mount point up
  	 */
  	private static function verifyMountPoint(&$share) {
  
  		$mountPoint = basename($share['file_target']);
  		$parent = dirname($share['file_target']);
  
  		while (!\OC\Files\Filesystem::is_dir($parent)) {
  			$parent = dirname($parent);
  		}
  
  		$newMountPoint = \OCA\Files_Sharing\Helper::generateUniqueTarget(
  				\OC\Files\Filesystem::normalizePath($parent . '/' . $mountPoint),
  				array(),
  				new \OC\Files\View('/' . \OCP\User::getUser() . '/files')
  				);
  
  		if($newMountPoint !== $share['file_target']) {
  			self::updateFileTarget($newMountPoint, $share);
  			$share['file_target'] = $newMountPoint;
  			$share['unique_name'] = true;
  		}
  
  		return $newMountPoint;
  	}
  
  	/**
  	 * update fileTarget in the database if the mount point changed
  	 * @param string $newPath
  	 * @param array $share reference to the share which should be modified
  	 * @return type
  	 */
  	private static function updateFileTarget($newPath, &$share) {
  		// if the user renames a mount point from a group share we need to create a new db entry
  		// for the unique name
  		if ($share['share_type'] === \OCP\Share::SHARE_TYPE_GROUP && empty($share['unique_name'])) {
  			$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share` (`item_type`, `item_source`, `item_target`,'
  			.' `share_type`, `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`,'
  			.' `file_target`, `token`, `parent`) VALUES (?,?,?,?,?,?,?,?,?,?,?,?)');
  			$arguments = array($share['item_type'], $share['item_source'], $share['item_target'],
  				2, \OCP\User::getUser(), $share['uid_owner'], $share['permissions'], $share['stime'], $share['file_source'],
  				$newPath, $share['token'], $share['id']);
  		} else {
  			// rename mount point
  			$query = \OC_DB::prepare(
  					'Update `*PREFIX*share`
  						SET `file_target` = ?
  						WHERE `id` = ?'
  					);
  			$arguments = array($newPath, $share['id']);
  		}
  
  		$result = $query->execute($arguments);
  
  		return $result === 1 ? true : false;
  	}
  
  	/**
  	 * Format a path to be relative to the /user/files/ directory
  	 *
  	 * @param string $path the absolute path
  	 * @return string e.g. turns '/admin/files/test.txt' into '/test.txt'
  	 */
  	private function stripUserFilesPath($path) {
  		$trimmed = ltrim($path, '/');
  		$split = explode('/', $trimmed);
  
  		// it is not a file relative to data/user/files
  		if (count($split) < 3 || $split[1] !== 'files') {
  			\OCP\Util::writeLog('file sharing',
  				'Can not strip userid and "files/" from path: ' . $path,
  				\OCP\Util::DEBUG);
  			return false;
  		}
  
  		// skip 'user' and 'files'
  		$sliced = array_slice($split, 2);
  		$relPath = implode('/', $sliced);
  
  		return '/' . $relPath;
  	}
  
  	/**
  	 * Move the mount point to $target
  	 *
  	 * @param string $target the target mount point
  	 * @return bool
  	 */
  	public function moveMount($target) {
  
  		$relTargetPath = $this->stripUserFilesPath($target);
  		$share = $this->storage->getShare();
  
  		$result = $this->updateFileTarget($relTargetPath, $share);
  
  		if ($result) {
  			$this->setMountPoint($target);
  			$this->storage->setUniqueName();
  			$this->storage->setMountPoint($relTargetPath);
  
  		} else {
  			\OCP\Util::writeLog('file sharing',
  				'Could not rename mount point for shared folder "' . $this->getMountPoint() . '" to "' . $target . '"',
  				\OCP\Util::ERROR);
  		}
  
  		return $result;
  	}
  
  	/**
  	 * Remove the mount points
  	 *
  	 * @return bool
  	 */
  	public function removeMount() {
  		$mountManager = \OC\Files\Filesystem::getMountManager();
  		$storage = $this->getStorage();
  		$result =  \OCP\Share::unshareFromSelf($storage->getItemType(), $storage->getMountPoint());
  		$mountManager->removeMount($this->mountPoint);
  
  		return $result;
  	}
  }