<?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\Storage;
  
  /**
   * Storage backend class for providing common filesystem operation methods
   * which are not storage-backend specific.
   *
   * \OC\Files\Storage\Common is never used directly; it is extended by all other
   * storage backends, where its methods may be overridden, and additional
   * (backend-specific) methods are defined.
   *
   * Some \OC\Files\Storage\Common methods call functions which are first defined
   * in classes which extend it, e.g. $this->stat() .
   */
  
  abstract class Common implements \OC\Files\Storage\Storage {
  	private $cache;
  	private $scanner;
  	private $permissioncache;
  	private $watcher;
  
  	public function __construct($parameters) {
  	}
  
  	public function is_dir($path) {
  		return $this->filetype($path) == 'dir';
  	}
  
  	public function is_file($path) {
  		return $this->filetype($path) == 'file';
  	}
  
  	public function filesize($path) {
  		if ($this->is_dir($path)) {
  			return 0; //by definition
  		} else {
  			$stat = $this->stat($path);
  			if (isset($stat['size'])) {
  				return $stat['size'];
  			} else {
  				return 0;
  			}
  		}
  	}
  
  	public function isCreatable($path) {
  		if ($this->is_dir($path) && $this->isUpdatable($path)) {
  			return true;
  		}
  		return false;
  	}
  
  	public function isDeletable($path) {
  		return $this->isUpdatable($path);
  	}
  
  	public function isSharable($path) {
  		return $this->isReadable($path);
  	}
  
  	public function getPermissions($path) {
  		$permissions = 0;
  		if ($this->isCreatable($path)) {
  			$permissions |= \OCP\PERMISSION_CREATE;
  		}
  		if ($this->isReadable($path)) {
  			$permissions |= \OCP\PERMISSION_READ;
  		}
  		if ($this->isUpdatable($path)) {
  			$permissions |= \OCP\PERMISSION_UPDATE;
  		}
  		if ($this->isDeletable($path)) {
  			$permissions |= \OCP\PERMISSION_DELETE;
  		}
  		if ($this->isSharable($path)) {
  			$permissions |= \OCP\PERMISSION_SHARE;
  		}
  		return $permissions;
  	}
  
  	public function filemtime($path) {
  		$stat = $this->stat($path);
  		if (isset($stat['mtime'])) {
  			return $stat['mtime'];
  		} else {
  			return 0;
  		}
  	}
  
  	public function file_get_contents($path) {
  		$handle = $this->fopen($path, "r");
  		if (!$handle) {
  			return false;
  		}
  		$size = $this->filesize($path);
  		if ($size == 0) {
  			return '';
  		}
  		return fread($handle, $size);
  	}
  
  	public function file_put_contents($path, $data) {
  		$handle = $this->fopen($path, "w");
  		return fwrite($handle, $data);
  	}
  
  	public function rename($path1, $path2) {
  		if ($this->copy($path1, $path2)) {
  			return $this->unlink($path1);
  		} else {
  			return false;
  		}
  	}
  
  	public function copy($path1, $path2) {
  		$source = $this->fopen($path1, 'r');
  		$target = $this->fopen($path2, 'w');
  		list($count, $result) = \OC_Helper::streamCopy($source, $target);
  		return $result;
  	}
  
  	/**
  	 * @brief Deletes all files and folders recursively within a directory
  	 * @param string $directory The directory whose contents will be deleted
  	 * @param bool $empty Flag indicating whether directory will be emptied
  	 * @returns bool
  	 *
  	 * @note By default the directory specified by $directory will be
  	 * deleted together with its contents. To avoid this set $empty to true
  	 */
  	public function deleteAll($directory, $empty = false) {
  		$directory = trim($directory, '/');
  		if (!$this->is_dir($directory) || !$this->isReadable($directory)) {
  			return false;
  		} else {
  			$directoryHandle = $this->opendir($directory);
  			if(is_resource($directoryHandle)) {
  				while (($contents = readdir($directoryHandle)) !== false) {
  					if (!\OC\Files\Filesystem::isIgnoredDir($contents)) {
  						$path = $directory . '/' . $contents;
  						if ($this->is_dir($path)) {
  							$this->deleteAll($path);
  						} else {
  							$this->unlink($path);
  						}
  					}
  				}
  			}
  			if ($empty === false) {
  				if (!$this->rmdir($directory)) {
  					return false;
  				}
  			}
  			return true;
  		}
  
  	}
  
  	public function getMimeType($path) {
  		if (!$this->file_exists($path)) {
  			return false;
  		}
  		if ($this->is_dir($path)) {
  			return 'httpd/unix-directory';
  		}
  		$source = $this->fopen($path, 'r');
  		if (!$source) {
  			return false;
  		}
  		$head = fread($source, 8192); //8kb should suffice to determine a mimetype
  		if ($pos = strrpos($path, '.')) {
  			$extension = substr($path, $pos);
  		} else {
  			$extension = '';
  		}
  		$tmpFile = \OC_Helper::tmpFile($extension);
  		file_put_contents($tmpFile, $head);
  		$mime = \OC_Helper::getMimeType($tmpFile);
  		unlink($tmpFile);
  		return $mime;
  	}
  
  	public function hash($type, $path, $raw = false) {
  		$tmpFile = $this->getLocalFile($path);
  		$hash = hash($type, $tmpFile, $raw);
  		unlink($tmpFile);
  		return $hash;
  	}
  
  	public function search($query) {
  		return $this->searchInDir($query);
  	}
  
  	public function getLocalFile($path) {
  		return $this->toTmpFile($path);
  	}
  
  	private function toTmpFile($path) { //no longer in the storage api, still useful here
  		$source = $this->fopen($path, 'r');
  		if (!$source) {
  			return false;
  		}
  		if ($pos = strrpos($path, '.')) {
  			$extension = substr($path, $pos);
  		} else {
  			$extension = '';
  		}
  		$tmpFile = \OC_Helper::tmpFile($extension);
  		$target = fopen($tmpFile, 'w');
  		\OC_Helper::streamCopy($source, $target);
  		return $tmpFile;
  	}
  
  	public function getLocalFolder($path) {
  		$baseDir = \OC_Helper::tmpFolder();
  		$this->addLocalFolder($path, $baseDir);
  		return $baseDir;
  	}
  
  	private function addLocalFolder($path, $target) {
  		if ($dh = $this->opendir($path)) {
  			if(!is_resource($dh)) {
  				return  null;
  			}
  			while (($file = readdir($dh)) !== false) {
  				if ($file !== '.' and $file !== '..') {
  					if ($this->is_dir($path . '/' . $file)) {
  						mkdir($target . '/' . $file);
  						$this->addLocalFolder($path . '/' . $file, $target . '/' . $file);
  					} else {
  						$tmp = $this->toTmpFile($path . '/' . $file);
  						rename($tmp, $target . '/' . $file);
  					}
  				}
  			}
  		}
  	}
  
  	protected function searchInDir($query, $dir = '') {
  		$files = array();
  		$dh = $this->opendir($dir);
  		if (is_resource($dh)) {
  			while (($item = readdir($dh)) !== false) {
  				if ($item == '.' || $item == '..') continue;
  				if (strstr(strtolower($item), strtolower($query)) !== false) {
  					$files[] = $dir . '/' . $item;
  				}
  				if ($this->is_dir($dir . '/' . $item)) {
  					$files = array_merge($files, $this->searchInDir($query, $dir . '/' . $item));
  				}
  			}
  		}
  		return $files;
  	}
  
  	/**
  	 * check if a file or folder has been updated since $time
  	 *
  	 * @param string $path
  	 * @param int $time
  	 * @return bool
  	 */
  	public function hasUpdated($path, $time) {
  		return $this->filemtime($path) > $time;
  	}
  
  	public function getCache($path = '') {
  		if (!isset($this->cache)) {
  			$this->cache = new \OC\Files\Cache\Cache($this);
  		}
  		return $this->cache;
  	}
  
  	public function getScanner($path = '') {
  		if (!isset($this->scanner)) {
  			$this->scanner = new \OC\Files\Cache\Scanner($this);
  		}
  		return $this->scanner;
  	}
  
  	public function getPermissionsCache($path = '') {
  		if (!isset($this->permissioncache)) {
  			$this->permissioncache = new \OC\Files\Cache\Permissions($this);
  		}
  		return $this->permissioncache;
  	}
  
  	public function getWatcher($path = '') {
  		if (!isset($this->watcher)) {
  			$this->watcher = new \OC\Files\Cache\Watcher($this);
  		}
  		return $this->watcher;
  	}
  
  	/**
  	 * get the owner of a path
  	 *
  	 * @param string $path The path to get the owner
  	 * @return string uid or false
  	 */
  	public function getOwner($path) {
  		return \OC_User::getUser();
  	}
  
  	/**
  	 * get the ETag for a file or folder
  	 *
  	 * @param string $path
  	 * @return string
  	 */
  	public function getETag($path) {
  		$ETagFunction = \OC_Connector_Sabre_Node::$ETagFunction;
  		if ($ETagFunction) {
  			$hash = call_user_func($ETagFunction, $path);
  			return $hash;
  		} else {
  			return uniqid();
  		}
  	}
  
  	/**
  	 * clean a path, i.e. remove all redundant '.' and '..'
  	 * making sure that it can't point to higher than '/'
  	 *
  	 * @param $path The path to clean
  	 * @return string cleaned path
  	 */
  	public function cleanPath($path) {
  		if (strlen($path) == 0 or $path[0] != '/') {
  			$path = '/' . $path;
  		}
  
  		$output = array();
  		foreach (explode('/', $path) as $chunk) {
  			if ($chunk == '..') {
  				array_pop($output);
  			} else if ($chunk == '.') {
  			} else {
  				$output[] = $chunk;
  			}
  		}
  		return implode('/', $output);
  	}
  
  	public function test() {
  		if ($this->stat('')) {
  			return true;
  		}
  		return false;
  	}
  
  	/**
  	 * get the free space in the storage
  	 *
  	 * @param $path
  	 * return int
  	 */
  	public function free_space($path) {
  		return \OC\Files\FREE_SPACE_UNKNOWN;
  	}
  }