<?php

/**
* ownCloud
*
* @author Frank Karlitschek
* @copyright 2012 Frank Karlitschek frank@owncloud.org
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library.  If not, see <http://www.gnu.org/licenses/>.
*
*/

/**
 * Class for fileserver access
 *
 */
class OC_Files {
	static $tmpFiles=array();

	/**
	 * get the filesystem info
	 * @param string path
	 * @return array
	 *
	 * returns an associative array with the following keys:
	 * - size
	 * - mtime
	 * - ctime
	 * - mimetype
	 * - encrypted
	 * - versioned
	 */
	public static function getFileInfo($path) {
		$path = OC_Filesystem::normalizePath($path);
		if (($path == '/Shared' || substr($path, 0, 8) == '/Shared/') && OC_App::isEnabled('files_sharing')) {
			if ($path == '/Shared') {
				list($info) = OCP\Share::getItemsSharedWith('file', OC_Share_Backend_File::FORMAT_FILE_APP_ROOT);
			} else {
				$info = array();
				if (OC_Filesystem::file_exists($path)) {
					$info['size'] = OC_Filesystem::filesize($path);
					$info['mtime'] = OC_Filesystem::filemtime($path);
					$info['ctime'] = OC_Filesystem::filectime($path);
					$info['mimetype'] = OC_Filesystem::getMimeType($path);
					$info['encrypted'] = false;
					$info['versioned'] = false;
				}
			}
		} else {
			$info = OC_FileCache::get($path);
		}
		return $info;
	}

	/**
	* get the content of a directory
	* @param dir $directory path under datadirectory
	*/
	public static function getDirectoryContent($directory, $mimetype_filter = '') {
		$directory=OC_Filesystem::normalizePath($directory);
		if($directory=='/') {
			$directory='';
		}
		$files = array();
		if (($directory == '/Shared' || substr($directory, 0, 8) == '/Shared/') && OC_App::isEnabled('files_sharing')) {
			if ($directory == '/Shared') {
				$files = OCP\Share::getItemsSharedWith('file', OC_Share_Backend_File::FORMAT_FILE_APP, array('folder' => $directory, 'mimetype_filter' => $mimetype_filter));
			} else {
				$pos = strpos($directory, '/', 8);
				// Get shared folder name
				if ($pos !== false) {
					$itemTarget = substr($directory, 7, $pos - 7);
				} else {
					$itemTarget = substr($directory, 7);
				}
				$files = OCP\Share::getItemSharedWith('folder', $itemTarget, OC_Share_Backend_File::FORMAT_FILE_APP, array('folder' => $directory, 'mimetype_filter' => $mimetype_filter));
			}
		} else {
			$files = OC_FileCache::getFolderContent($directory, false, $mimetype_filter);
			foreach ($files as &$file) {
				$file['directory'] = $directory;
				$file['type'] = ($file['mimetype'] == 'httpd/unix-directory') ? 'dir' : 'file';
				$permissions = OCP\PERMISSION_READ;
				// NOTE: Remove check when new encryption is merged
				if (!$file['encrypted']) {
					$permissions |= OCP\PERMISSION_SHARE;
				}
				if ($file['type'] == 'dir' && $file['writable']) {
					$permissions |= OCP\PERMISSION_CREATE;
				}
				if ($file['writable']) {
					$permissions |= OCP\PERMISSION_UPDATE | OCP\PERMISSION_DELETE;
				}
				$file['permissions'] = $permissions;
			}
			if ($directory == '' && OC_App::isEnabled('files_sharing')) {
				// Add 'Shared' folder
				$files = array_merge($files, OCP\Share::getItemsSharedWith('file', OC_Share_Backend_File::FORMAT_FILE_APP_ROOT));
			}
		}
		usort($files, "fileCmp");//TODO: remove this once ajax is merged
		return $files;
	}

	public static function searchByMime($mimetype_filter) {
		$files = array();
		$dirs_to_check = array('');
		while (!empty($dirs_to_check)) {
			// get next subdir to check
			$dir = array_pop($dirs_to_check);
			$dir_content = self::getDirectoryContent($dir, $mimetype_filter);
			foreach($dir_content as $file) {
				if ($file['type'] == 'file') {
					$files[] = $dir.'/'.$file['name'];
				}
				else {
					$dirs_to_check[] = $dir.'/'.$file['name'];
				}
			}
		}
		return $files;
	}

	/**
	* return the content of a file or return a zip file containning multiply files
	*
	* @param dir  $dir
	* @param file $file ; seperated list of files to download
	* @param boolean $only_header ; boolean to only send header of the request
	*/
	public static function get($dir, $files, $only_header = false) {
		$xsendfile = false;
		if (isset($_SERVER['MOD_X_SENDFILE_ENABLED']) ||
			isset($_SERVER['MOD_X_ACCEL_REDIRECT_ENABLED'])) {
			$xsendfile = true;
		}
		if(strpos($files, ';')) {
			$files=explode(';', $files);
		}

		if(is_array($files)) {
			self::validateZipDownload($dir, $files);
			$executionTime = intval(ini_get('max_execution_time'));
			set_time_limit(0);
			$zip = new ZipArchive();
			if ($xsendfile) {
				$filename = OC_Helper::tmpFileNoClean('.zip');
			}else{
				$filename = OC_Helper::tmpFile('.zip');
			}
			if ($zip->open($filename, ZIPARCHIVE::CREATE | ZIPARCHIVE::OVERWRITE)!==true) {
				exit("cannot open <$filename>\n");
			}
			foreach($files as $file) {
				$file=$dir.'/'.$file;
				if(OC_Filesystem::is_file($file)) {
					$tmpFile=OC_Filesystem::toTmpFile($file);
					self::$tmpFiles[]=$tmpFile;
					$zip->addFile($tmpFile, basename($file));
				}elseif(OC_Filesystem::is_dir($file)) {
					self::zipAddDir($file, $zip);
				}
			}
			$zip->close();
			set_time_limit($executionTime);
		}elseif(OC_Filesystem::is_dir($dir.'/'.$files)) {
			self::validateZipDownload($dir, $files);
			$executionTime = intval(ini_get('max_execution_time'));
			set_time_limit(0);
			$zip = new ZipArchive();
			if ($xsendfile) {
				$filename = OC_Helper::tmpFileNoClean('.zip');
			}else{
				$filename = OC_Helper::tmpFile('.zip');
			}
			if ($zip->open($filename, ZIPARCHIVE::CREATE | ZIPARCHIVE::OVERWRITE)!==true) {
				exit("cannot open <$filename>\n");
			}
			$file=$dir.'/'.$files;
			self::zipAddDir($file, $zip);
			$zip->close();
			set_time_limit($executionTime);
		}else{
			$zip=false;
			$filename=$dir.'/'.$files;
		}
		OC_Util::obEnd();
		if($zip or OC_Filesystem::is_readable($filename)) {
			if ( preg_match( "/MSIE/", $_SERVER["HTTP_USER_AGENT"] ) ) {
				header( 'Content-Disposition: attachment; filename="' . rawurlencode( basename($filename) ) . '"' );
			} else {
				header( 'Content-Disposition: attachment; filename*=UTF-8\'\'' . rawurlencode( basename($filename) )
													 . '; filename="' . rawurlencode( basename($filename) ) . '"' );
			}
			header('Content-Transfer-Encoding: binary');
			OC_Response::disableCaching();
			if($zip) {
				ini_set('zlib.output_compression', 'off');
				header('Content-Type: application/zip');
				header('Content-Length: ' . filesize($filename));
				self::addSendfileHeader($filename);
			}else{
				header('Content-Type: '.OC_Filesystem::getMimeType($filename));
				header("Content-Length: ".OC_Filesystem::filesize($filename));
				$storage = OC_Filesystem::getStorage($filename);
				if ($storage instanceof OC_Filestorage_Local) {
					self::addSendfileHeader(OC_Filesystem::getLocalFile($filename));
				}
			}
		}elseif($zip or !OC_Filesystem::file_exists($filename)) {
			header("HTTP/1.0 404 Not Found");
			$tmpl = new OC_Template( '', '404', 'guest' );
			$tmpl->assign('file', $filename);
			$tmpl->printPage();
		}else{
			header("HTTP/1.0 403 Forbidden");
			die('403 Forbidden');
		}
		if($only_header) {
			return ;
		}
		if($zip) {
			$handle=fopen($filename, 'r');
			if ($handle) {
				$chunkSize = 8*1024;// 1 MB chunks
				while (!feof($handle)) {
					echo fread($handle, $chunkSize);
					flush();
				}
			}
			if (!$xsendfile) {
				unlink($filename);
			}
		}else{
			OC_Filesystem::readfile($filename);
		}
		foreach(self::$tmpFiles as $tmpFile) {
			if(file_exists($tmpFile) and is_file($tmpFile)) {
				unlink($tmpFile);
			}
		}
	}

	private static function addSendfileHeader($filename) {
		if (isset($_SERVER['MOD_X_SENDFILE_ENABLED'])) {
			header("X-Sendfile: " . $filename);
		}
		if (isset($_SERVER['MOD_X_ACCEL_REDIRECT_ENABLED'])) {
			header("X-Accel-Redirect: " . $filename);
		}
	}

	public static function zipAddDir($dir, $zip, $internalDir='') {
		$dirname=basename($dir);
		$zip->addEmptyDir($internalDir.$dirname);
		$internalDir.=$dirname.='/';
		$files=OC_Files::getDirectoryContent($dir);
		foreach($files as $file) {
			$filename=$file['name'];
			$file=$dir.'/'.$filename;
			if(OC_Filesystem::is_file($file)) {
				$tmpFile=OC_Filesystem::toTmpFile($file);
				OC_Files::$tmpFiles[]=$tmpFile;
				$zip->addFile($tmpFile, $internalDir.$filename);
			}elseif(OC_Filesystem::is_dir($file)) {
				self::zipAddDir($file, $zip, $internalDir);
			}
		}
	}
	/**
	* move a file or folder
	*
	* @param dir  $sourceDir
	* @param file $source
	* @param dir  $targetDir
	* @param file $target
	*/
	public static function move($sourceDir, $source, $targetDir, $target) {
		if(OC_User::isLoggedIn() && ($sourceDir != '' || $source != 'Shared')) {
			$targetFile=self::normalizePath($targetDir.'/'.$target);
			$sourceFile=self::normalizePath($sourceDir.'/'.$source);
			return OC_Filesystem::rename($sourceFile, $targetFile);
		} else {
			return false;
		}
	}

	/**
	* copy a file or folder
	*
	* @param dir  $sourceDir
	* @param file $source
	* @param dir  $targetDir
	* @param file $target
	*/
	public static function copy($sourceDir, $source, $targetDir, $target) {
		if(OC_User::isLoggedIn()) {
			$targetFile=$targetDir.'/'.$target;
			$sourceFile=$sourceDir.'/'.$source;
			return OC_Filesystem::copy($sourceFile, $targetFile);
		}
	}

	/**
	* create a new file or folder
	*
	* @param dir  $dir
	* @param file $name
	* @param type $type
	*/
	public static function newFile($dir, $name, $type) {
		if(OC_User::isLoggedIn()) {
			$file=$dir.'/'.$name;
			if($type=='dir') {
				return OC_Filesystem::mkdir($file);
			}elseif($type=='file') {
				$fileHandle=OC_Filesystem::fopen($file, 'w');
				if($fileHandle) {
					fclose($fileHandle);
					return true;
				}else{
					return false;
				}
			}
		}
	}

	/**
	* deletes a file or folder
	*
	* @param dir  $dir
	* @param file $name
	*/
	public static function delete($dir, $file) {
		if(OC_User::isLoggedIn() && ($dir!= '' || $file != 'Shared')) {
			$file=$dir.'/'.$file;
			return OC_Filesystem::unlink($file);
		}
	}

	/**
	* checks if the selected files are within the size constraint. If not, outputs an error page.
	*
	* @param dir   $dir
	* @param files $files
	*/
	static function validateZipDownload($dir, $files) {
		if(!OC_Config::getValue('allowZipDownload', true)) {
			$l = OC_L10N::get('lib');
			header("HTTP/1.0 409 Conflict");
			$tmpl = new OC_Template( '', 'error', 'user' );
			$errors = array(
				array(
					'error' => $l->t('ZIP download is turned off.'),
					'hint' => $l->t('Files need to be downloaded one by one.') . '<br/><a href="javascript:history.back()">' . $l->t('Back to Files') . '</a>',
				)
			);
			$tmpl->assign('errors', $errors);
			$tmpl->printPage();
			exit;
		}

		$zipLimit = OC_Config::getValue('maxZipInputSize', OC_Helper::computerFileSize('800 MB'));
		if($zipLimit > 0) {
			$totalsize = 0;
			if(is_array($files)) {
				foreach($files as $file) {
					$totalsize += OC_Filesystem::filesize($dir.'/'.$file);
				}
			}else{
				$totalsize += OC_Filesystem::filesize($dir.'/'.$files);
			}
			if($totalsize > $zipLimit) {
				$l = OC_L10N::get('lib');
				header("HTTP/1.0 409 Conflict");
				$tmpl = new OC_Template( '', 'error', 'user' );
				$errors = array(
					array(
						'error' => $l->t('Selected files too large to generate zip file.'),
						'hint' => 'Download the files in smaller chunks, seperately or kindly ask your administrator.<br/><a href="javascript:history.back()">' . $l->t('Back to Files') . '</a>',
					)
				);
				$tmpl->assign('errors', $errors);
				$tmpl->printPage();
				exit;
			}
		}
	}

	/**
	* try to detect the mime type of a file
	*
	* @param  string  path
	* @return string  guessed mime type
	*/
	static function getMimeType($path) {
		return OC_Filesystem::getMimeType($path);
	}

	/**
	* get a file tree
	*
	* @param  string  path
	* @return array
	*/
	static function getTree($path) {
		return OC_Filesystem::getTree($path);
	}

	/**
	* pull a file from a remote server
	* @param  string  source
	* @param  string  token
	* @param  string  dir
	* @param  string  file
	* @return string  guessed mime type
	*/
	static function pull($source, $token, $dir, $file) {
		$tmpfile=tempnam(get_temp_dir(), 'remoteCloudFile');
		$fp=fopen($tmpfile, 'w+');
		$url=$source.="/files/pull.php?token=$token";
		$ch=curl_init();
		curl_setopt($ch, CURLOPT_URL, $url);
		curl_setopt($ch, CURLOPT_FILE, $fp);
		curl_exec($ch);
		fclose($fp);
		$info=curl_getinfo($ch);
		$httpCode=$info['http_code'];
		curl_close($ch);
		if($httpCode==200 or $httpCode==0) {
			OC_Filesystem::fromTmpFile($tmpfile, $dir.'/'.$file);
			return true;
		}else{
			return false;
		}
	}

	/**
	 * set the maximum upload size limit for apache hosts using .htaccess
	 * @param int size filesisze in bytes
	 * @return false on failure, size on success
	 */
	static function setUploadLimit($size) {
		//don't allow user to break his config -- upper boundary
		if($size > PHP_INT_MAX) {
			//max size is always 1 byte lower than computerFileSize returns
			if($size > PHP_INT_MAX+1)
				return false;
			$size -=1;
		} else {
			$size=OC_Helper::humanFileSize($size);
			$size=substr($size, 0, -1);//strip the B
			$size=str_replace(' ', '', $size); //remove the space between the size and the postfix
		}

		//don't allow user to break his config -- broken or malicious size input
		if(intval($size) == 0) {
			return false;
		}

		$htaccess = @file_get_contents(OC::$SERVERROOT.'/.htaccess'); //supress errors in case we don't have permissions for
		if(!$htaccess) {
			return false;
		}

		$phpValueKeys = array(
			'upload_max_filesize',
			'post_max_size'
		);

		foreach($phpValueKeys as $key) {
		    $pattern = '/php_value '.$key.' (\S)*/';
		    $setting = 'php_value '.$key.' '.$size;
		    $hasReplaced = 0;
		    $content = preg_replace($pattern, $setting, $htaccess, 1, $hasReplaced);
		    if($content !== null) {
				$htaccess = $content;
			}
			if($hasReplaced == 0) {
				$htaccess .= "\n" . $setting;
			}
		}

		//check for write permissions
		if(is_writable(OC::$SERVERROOT.'/.htaccess')) {
			file_put_contents(OC::$SERVERROOT.'/.htaccess', $htaccess);
			return OC_Helper::computerFileSize($size);
		} else {
			OC_Log::write('files', 'Can\'t write upload limit to '.OC::$SERVERROOT.'/.htaccess. Please check the file permissions', OC_Log::WARN);
		}

		return false;
	}

	/**
	 * normalize a path, removing any double, add leading /, etc
	 * @param string $path
	 * @return string
	 */
	static public function normalizePath($path) {
		$path='/'.$path;
		$old='';
		while($old!=$path) {//replace any multiplicity of slashes with a single one
			$old=$path;
			$path=str_replace('//', '/', $path);
		}
		return $path;
	}
}

function fileCmp($a, $b) {
	if($a['type']=='dir' and $b['type']!='dir') {
		return -1;
	}elseif($a['type']!='dir' and $b['type']=='dir') {
		return 1;
	}else{
		return strnatcasecmp($a['name'], $b['name']);
	}
}