<?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.
   */
  
  require_once OC::$THIRDPARTYROOT . '/3rdparty/Archive/Tar.php';
  
  class OC_Archive_TAR extends OC_Archive{
  	const PLAIN=0;
  	const GZIP=1;
  	const BZIP=2;
  
  	private $fileList;
  	private $cachedHeaders;
  
  	/**
  	 * @var Archive_Tar tar
  	 */
  	private $tar=null;
  	private $path;

  	/**
  	 * @param string $source
  	 */

  	function __construct($source) {
  		$types=array(null, 'gz', 'bz');
  		$this->path=$source;
  		$this->tar=new Archive_Tar($source, $types[self::getTarType($source)]);
  	}
  
  	/**
  	 * try to detect the type of tar compression

  	 * @param string $file
  	 * @return integer

  	 */
  	static public function getTarType($file) {
  		if(strpos($file, '.')) {
  			$extension=substr($file, strrpos($file, '.'));
  			switch($extension) {
  				case 'gz':
  				case 'tgz':
  					return self::GZIP;
  				case 'bz':
  				case 'bz2':
  					return self::BZIP;
  				default:
  					return self::PLAIN;
  			}
  		}else{
  			return self::PLAIN;
  		}
  	}
  
  	/**
  	 * add an empty folder to the archive

  	 * @param string $path

  	 * @return bool
  	 */
  	function addFolder($path) {
  		$tmpBase=OC_Helper::tmpFolder();
  		if(substr($path, -1, 1)!='/') {
  			$path.='/';
  		}
  		if($this->fileExists($path)) {
  			return false;
  		}
  		$parts=explode('/', $path);
  		$folder=$tmpBase;
  		foreach($parts as $part) {
  			$folder.='/'.$part;
  			if(!is_dir($folder)) {
  				mkdir($folder);
  			}
  		}
  		$result=$this->tar->addModify(array($tmpBase.$path), '', $tmpBase);
  		rmdir($tmpBase.$path);
  		$this->fileList=false;
  		$this->cachedHeaders=false;
  		return $result;
  	}
  	/**
  	 * add a file to the archive

  	 * @param string $path
  	 * @param string $source either a local file or string data

  	 * @return bool
  	 */
  	function addFile($path, $source='') {
  		if($this->fileExists($path)) {
  			$this->remove($path);
  		}
  		if($source and $source[0]=='/' and file_exists($source)) {
  			$header=array();
  			$dummy='';
  			$this->tar->_openAppend();
  			$result=$this->tar->_addfile($source, $header, $dummy, $dummy, $path);
  		}else{
  			$result=$this->tar->addString($path, $source);
  		}
  		$this->fileList=false;
  		$this->cachedHeaders=false;
  		return $result;
  	}
  
  	/**
  	 * rename a file or folder in the archive

  	 * @param string $source
  	 * @param string $dest

  	 * @return bool
  	 */
  	function rename($source, $dest) {
  		//no proper way to delete, rename entire archive, rename file and remake archive
  		$tmp=OCP\Files::tmpFolder();
  		$this->tar->extract($tmp);
  		rename($tmp.$source, $tmp.$dest);
  		$this->tar=null;
  		unlink($this->path);
  		$types=array(null, 'gz', 'bz');
  		$this->tar=new Archive_Tar($this->path, $types[self::getTarType($this->path)]);
  		$this->tar->createModify(array($tmp), '', $tmp.'/');
  		$this->fileList=false;
  		$this->cachedHeaders=false;
  		return true;
  	}

  	/**
  	 * @param string $file
  	 */

  	private function getHeader($file) {
  		if ( ! $this->cachedHeaders ) {
  			$this->cachedHeaders = $this->tar->listContent();
  		}
  		foreach($this->cachedHeaders as $header) {
  			if(        $file     == $header['filename']
  				or     $file.'/' == $header['filename']
  				or '/'.$file.'/' == $header['filename']
  				or '/'.$file     == $header['filename']) {
  				return $header;
  			}
  		}
  		return null;
  	}
  
  	/**
  	 * get the uncompressed size of a file in the archive

  	 * @param string $path

  	 * @return int
  	 */
  	function filesize($path) {
  		$stat=$this->getHeader($path);
  		return $stat['size'];
  	}
  	/**
  	 * get the last modified time of a file in the archive

  	 * @param string $path

  	 * @return int
  	 */
  	function mtime($path) {
  		$stat=$this->getHeader($path);
  		return $stat['mtime'];
  	}
  
  	/**
  	 * get the files in a folder

  	 * @param string $path

  	 * @return array
  	 */
  	function getFolder($path) {
  		$files=$this->getFiles();
  		$folderContent=array();
  		$pathLength=strlen($path);
  		foreach($files as $file) {
  			if($file[0]=='/') {
  				$file=substr($file, 1);
  			}
  			if(substr($file, 0, $pathLength)==$path and $file!=$path) {
  				$result=substr($file, $pathLength);
  				if($pos=strpos($result, '/')) {
  					$result=substr($result, 0, $pos+1);
  				}
  				if(array_search($result, $folderContent)===false) {
  					$folderContent[]=$result;
  				}
  			}
  		}
  		return $folderContent;
  	}
  	/**

  	 * get all files in the archive

  	 * @return array
  	 */
  	function getFiles() {
  		if($this->fileList) {
  			return $this->fileList;
  		}
  		if ( ! $this->cachedHeaders ) {
  			$this->cachedHeaders = $this->tar->listContent();
  		}
  		$files=array();
  		foreach($this->cachedHeaders as $header) {
  			$files[]=$header['filename'];
  		}
  		$this->fileList=$files;
  		return $files;
  	}
  	/**
  	 * get the content of a file

  	 * @param string $path

  	 * @return string
  	 */
  	function getFile($path) {
  		return $this->tar->extractInString($path);
  	}
  	/**
  	 * extract a single file from the archive

  	 * @param string $path
  	 * @param string $dest

  	 * @return bool
  	 */
  	function extractFile($path, $dest) {
  		$tmp=OCP\Files::tmpFolder();
  		if(!$this->fileExists($path)) {
  			return false;
  		}
  		if($this->fileExists('/'.$path)) {
  			$success=$this->tar->extractList(array('/'.$path), $tmp);
  		}else{
  			$success=$this->tar->extractList(array($path), $tmp);
  		}
  		if($success) {
  			rename($tmp.$path, $dest);
  		}
  		OCP\Files::rmdirr($tmp);
  		return $success;
  	}
  	/**
  	 * extract the archive

  	 * @param string $dest

  	 * @return bool
  	 */
  	function extract($dest) {
  		return $this->tar->extract($dest);
  	}
  	/**
  	 * check if a file or folder exists in the archive

  	 * @param string $path

  	 * @return bool
  	 */
  	function fileExists($path) {
  		$files=$this->getFiles();
  		if((array_search($path, $files)!==false) or (array_search($path.'/', $files)!==false)) {
  			return true;
  		}else{
  			$folderPath=$path;
  			if(substr($folderPath, -1, 1)!='/') {
  				$folderPath.='/';
  			}
  			$pathLength=strlen($folderPath);
  			foreach($files as $file) {
  				if(strlen($file)>$pathLength and substr($file, 0, $pathLength)==$folderPath) {
  					return true;
  				}
  			}
  		}
  		if($path[0]!='/') {//not all programs agree on the use of a leading /
  			return $this->fileExists('/'.$path);
  		}else{
  			return false;
  		}
  	}
  
  	/**
  	 * remove a file or folder from the archive

  	 * @param string $path

  	 * @return bool
  	 */
  	function remove($path) {
  		if(!$this->fileExists($path)) {
  			return false;
  		}
  		$this->fileList=false;
  		$this->cachedHeaders=false;
  		//no proper way to delete, extract entire archive, delete file and remake archive
  		$tmp=OCP\Files::tmpFolder();
  		$this->tar->extract($tmp);
  		OCP\Files::rmdirr($tmp.$path);
  		$this->tar=null;
  		unlink($this->path);
  		$this->reopen();
  		$this->tar->createModify(array($tmp), '', $tmp);
  		return true;
  	}
  	/**
  	 * get a file handler

  	 * @param string $path
  	 * @param string $mode

  	 * @return resource
  	 */
  	function getStream($path, $mode) {
  		if(strrpos($path, '.')!==false) {
  			$ext=substr($path, strrpos($path, '.'));
  		}else{
  			$ext='';
  		}
  		$tmpFile=OCP\Files::tmpFile($ext);
  		if($this->fileExists($path)) {
  			$this->extractFile($path, $tmpFile);
  		}elseif($mode=='r' or $mode=='rb') {
  			return false;
  		}
  		if($mode=='r' or $mode=='rb') {
  			return fopen($tmpFile, $mode);
  		}else{
  			\OC\Files\Stream\Close::registerCallback($tmpFile, array($this, 'writeBack'));
  			self::$tempFiles[$tmpFile]=$path;
  			return fopen('close://'.$tmpFile, $mode);
  		}
  	}
  
  	private static $tempFiles=array();
  	/**
  	 * write back temporary files
  	 */
  	function writeBack($tmpFile) {
  		if(isset(self::$tempFiles[$tmpFile])) {
  			$this->addFile(self::$tempFiles[$tmpFile], $tmpFile);
  			unlink($tmpFile);
  		}
  	}
  
  	/**
  	 * reopen the archive to ensure everything is written
  	 */
  	private function reopen() {
  		if($this->tar) {
  			$this->tar->_close();
  			$this->tar=null;
  		}
  		$types=array(null, 'gz', 'bz');
  		$this->tar=new Archive_Tar($this->path, $types[self::getTarType($this->path)]);
  	}
  }