<?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();

  	static public function getFileInfo($path, $includeMountPoints = true){
  		return \OC\Files\Filesystem::getFileInfo($path, $includeMountPoints);

  	}
  
  	static public function getDirectoryContent($path){
  		return \OC\Files\Filesystem::getDirectoryContent($path);
  	}
  
  	/**
  	 * return the content of a file or return a zip file containing multiple files
  	 *
  	 * @param string $dir
  	 * @param string $file ; separated 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_SENDFILE2_ENABLED']) ||

  			isset($_SERVER['MOD_X_ACCEL_REDIRECT_ENABLED'])) {
  			$xsendfile = true;
  		}
  
  		if (is_array($files) && count($files) == 1) {
  			$files = $files[0];
  		}
  
  		if (is_array($files)) {
  			self::validateZipDownload($dir, $files);
  			$executionTime = intval(ini_get('max_execution_time'));
  			set_time_limit(0);
  			$zip = new ZipArchive();

  			$filename = OC_Helper::tmpFile('.zip');

  			if ($zip->open($filename, ZIPARCHIVE::CREATE | ZIPARCHIVE::OVERWRITE)!==true) {

  				$l = OC_L10N::get('lib');
  				throw new Exception($l->t('cannot open "%s"', array($filename)));

  			}
  			foreach ($files as $file) {
  				$file = $dir . '/' . $file;
  				if (\OC\Files\Filesystem::is_file($file)) {
  					$tmpFile = \OC\Files\Filesystem::toTmpFile($file);
  					self::$tmpFiles[] = $tmpFile;
  					$zip->addFile($tmpFile, basename($file));
  				} elseif (\OC\Files\Filesystem::is_dir($file)) {
  					self::zipAddDir($file, $zip);
  				}
  			}
  			$zip->close();

  			if ($xsendfile) {
  				$filename = OC_Helper::moveToNoClean($filename);
  			}

  			$basename = basename($dir);
  			if ($basename) {
  				$name = $basename . '.zip';
  			} else {

  				$name = 'download.zip';

  			}
  			
  			set_time_limit($executionTime);
  		} elseif (\OC\Files\Filesystem::is_dir($dir . '/' . $files)) {
  			self::validateZipDownload($dir, $files);
  			$executionTime = intval(ini_get('max_execution_time'));
  			set_time_limit(0);
  			$zip = new ZipArchive();

  			$filename = OC_Helper::tmpFile('.zip');

  			if ($zip->open($filename, ZIPARCHIVE::CREATE | ZIPARCHIVE::OVERWRITE)!==true) {

  				$l = OC_L10N::get('lib');
  				throw new Exception($l->t('cannot open "%s"', array($filename)));

  			}
  			$file = $dir . '/' . $files;
  			self::zipAddDir($file, $zip);
  			$zip->close();

  			if ($xsendfile) {
  				$filename = OC_Helper::moveToNoClean($filename);
  			}

  			$name = $files . '.zip';
  			set_time_limit($executionTime);
  		} else {
  			$zip = false;
  			$filename = $dir . '/' . $files;
  			$name = $files;

  			if ($xsendfile && OC_App::isEnabled('files_encryption')) {
  				$xsendfile = false;
  			}

  		}
  		OC_Util::obEnd();
  		if ($zip or \OC\Files\Filesystem::isReadable($filename)) {

  			OC_Response::setContentDispositionHeader($name, 'attachment');

  			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{

  				$filesize = \OC\Files\Filesystem::filesize($filename);

  				header('Content-Type: '.\OC\Files\Filesystem::getMimeType($filename));

  				if ($filesize > -1) {
  					header("Content-Length: ".$filesize);
  				}
  				if ($xsendfile) {
  					list($storage) = \OC\Files\Filesystem::resolvePath(\OC\Files\Filesystem::getView()->getAbsolutePath($filename));

  					if ($storage instanceof \OC\Files\Storage\Wrapper\Wrapper) {
  						$storage = $storage->getWrapperStorage();
  					}

  					if ($storage instanceof \OC\Files\Storage\Local) {
  						self::addSendfileHeader(\OC\Files\Filesystem::getLocalFile($filename));
  					}

  				}
  			}
  		} elseif ($zip or !\OC\Files\Filesystem::file_exists($filename)) {
  			header("HTTP/1.0 404 Not Found");
  			$tmpl = new OC_Template('', '404', 'guest');
  			$tmpl->assign('file', $name);
  			$tmpl->printPage();
  		} else {
  			header("HTTP/1.0 403 Forbidden");
  			die('403 Forbidden');
  		}
  		if($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($filename);
  			}
  		}else{
  			\OC\Files\Filesystem::readfile($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($_SERVER['MOD_X_SENDFILE2_ENABLED'])) {
  			if (isset($_SERVER['HTTP_RANGE']) && 
  				preg_match("/^bytes=([0-9]+)-([0-9]*)$/", $_SERVER['HTTP_RANGE'], $range)) {
  				$filelength = filesize($filename);
   				if ($range[2] == "") {
   					$range[2] = $filelength - 1;
   				}
   				header("Content-Range: bytes $range[1]-$range[2]/" . $filelength);
   				header("HTTP/1.1 206 Partial content");
   				header("X-Sendfile2: " . str_replace(",", "%2c", rawurlencode($filename)) . " $range[1]-$range[2]");
   			} else {
   				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.'/'.$filename;
  			if(\OC\Files\Filesystem::is_file($file)) {
  				$tmpFile=\OC\Files\Filesystem::toTmpFile($file);
  				OC_Files::$tmpFiles[]=$tmpFile;
  				$zip->addFile($tmpFile, $internalDir.$filename);
  			}elseif(\OC\Files\Filesystem::is_dir($file)) {
  				self::zipAddDir($file, $zip, $internalDir);
  			}
  		}
  	}
  
  	/**
  	 * 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");

  			OC_Template::printErrorPage(
  					$l->t('ZIP download is turned off.'),
  					$l->t('Files need to be downloaded one by one.')
  						. '<br/><a href="javascript:history.back()">' . $l->t('Back to Files') . '</a>'

  			);

  			exit;
  		}
  
  		$zipLimit = OC_Config::getValue('maxZipInputSize', OC_Helper::computerFileSize('800 MB'));
  		if ($zipLimit > 0) {
  			$totalsize = 0;
  			if(!is_array($files)) {
  				$files = array($files);
  			}
  			foreach ($files as $file) {
  				$path = $dir . '/' . $file;
  				if(\OC\Files\Filesystem::is_dir($path)) {
  					foreach (\OC\Files\Filesystem::getDirectoryContent($path) as $i) {
  						$totalsize += $i['size'];
  					}
  				} else {
  					$totalsize += \OC\Files\Filesystem::filesize($path);
  				}
  			}
  			if ($totalsize > $zipLimit) {
  				$l = OC_L10N::get('lib');
  				header("HTTP/1.0 409 Conflict");

  				OC_Template::printErrorPage(
  						$l->t('Selected files too large to generate zip file.'),
  						$l->t('Please download the files separately in smaller chunks or kindly ask your administrator.')
  						.'<br/><a href="javascript:history.back()">'
  						. $l->t('Back to Files') . '</a>'

  				);

  				exit;
  			}
  		}
  	}
  
  	/**
  	 * 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 .= "
  " . $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;
  	}
  }