<?php

/**
* ownCloud
*
* @author Frank Karlitschek
* @copyright 2010 Frank Karlitschek karlitschek@kde.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 OC_FilesystemView {
	private $fakeRoot='';
	
	public function __construct($root){
		$this->fakeRoot=$root;
	}
	
	public function getAbsolutePath($path){
		if(!$path){
			$path='/';
		}
		if(substr($path,0,1)!=='/'){
			$path='/'.$path;
		}
		return $this->fakeRoot.$path;
	}


	/**
	* change the root to a fake toor
	* @param  string  fakeRoot
	* @return bool
	*/
	public function chroot($fakeRoot){
		if(!$fakeRoot==''){
			if($fakeRoot[0]!=='/'){
				$fakeRoot='/'.$fakeRoot;
			}
		}
		$this->fakeRoot=$fakeRoot;
	}

	/**
	 * get the fake root
	 * @return string
	 */
	public function getRoot(){
		return $this->fakeRoot;
	}

	/**
	* get the part of the path relative to the mountpoint of the storage it's stored in
	* @param  string  path
	* @return bool
	*/
	public function getInternalPath($path){
		return OC_Filesystem::getInternalPath($this->getAbsolutePath($path));
	}
	/**
	* get the storage object for a path
	* @param string path
	* @return OC_Filestorage
	*/
	public function getStorage($path){
		return OC_Filesystem::getStorage($this->getAbsolutePath($path));
	}

	/**
	* get the mountpoint of the storage object for a path
	( note: because a storage is not always mounted inside the fakeroot, the returned mountpoint is relative to the absolute root of the filesystem and doesn't take the chroot into account
	*
	* @param string path
	* @return string
	*/
	public function getMountPoint($path){
		return OC_Filesystem::getMountPoint($this->getAbsolutePath($path));
	}

	/**
	* return the path to a local version of the file
	* we need this because we can't know if a file is stored local or not from outside the filestorage and for some purposes a local file is needed
	* @param string path
	* @return string
	*/
	public function getLocalFile($path){
		$parent=substr($path,0,strrpos($path,'/'));
		if(OC_Filesystem::isValidPath($parent) and $storage=$this->getStorage($path)){
			return $storage->getLocalFile($this->getInternalPath($path));
		}
	}

	/**
	 * following functions are equivilent to their php buildin equivilents for arguments/return values.
	 */
	public function mkdir($path){
		return $this->basicOperation('mkdir',$path,array('create','write'));
	}
	public function rmdir($path){
		return $this->basicOperation('rmdir',$path,array('delete'));
	}
	public function opendir($path){
		return $this->basicOperation('opendir',$path,array('read'));
	}
	public function is_dir($path){
		if($path=='/'){
			return true;
		}
		return $this->basicOperation('is_dir',$path);
	}
	public function is_file($path){
		if($path=='/'){
			return false;
		}
		return $this->basicOperation('is_file',$path);
	}
	public function stat($path){
		return $this->basicOperation('stat',$path);
	}
	public function filetype($path){
		return $this->basicOperation('filetype',$path);
	}
	public function filesize($path){
		return $this->basicOperation('filesize',$path);
	}
	public function readfile($path){
		return $this->basicOperation('readfile',$path,array('read'));
	}
	public function is_readable($path){
		return $this->basicOperation('is_readable',$path);
	}
	public function is_writable($path){
		return $this->basicOperation('is_writable',$path);
	}
	public function file_exists($path){
		if($path=='/'){
			return true;
		}
		return $this->basicOperation('file_exists',$path);
	}
	public function filectime($path){
		return $this->basicOperation('filectime',$path);
	}
	public function filemtime($path){
		return $this->basicOperation('filemtime',$path);
	}
	public function file_get_contents($path){
		return $this->basicOperation('file_get_contents',$path,array('read'));
	}
	public function file_put_contents($path,$data){
		return $this->basicOperation('file_put_contents',$path,array('create','write'),$data);
	}
	public function unlink($path){
		return $this->basicOperation('unlink',$path,array('delete'));
	}
	public function rename($path1,$path2){
		if(OC_FileProxy::runPreProxies('rename',$path1,$path2) and $this->is_writable($path1) and OC_Filesystem::isValidPath($path2)){
			$run=true;
			OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_rename, array( OC_Filesystem::signal_param_oldpath => $path1 , OC_Filesystem::signal_param_newpath=>$path2, OC_Filesystem::signal_param_run => &$run));
			if($run){
				$mp1=$this->getMountPoint($path1);
				$mp2=$this->getMountPoint($path2);
				if($mp1==$mp2){
					if($storage=$this->getStorage($path1)){
						$result=$storage->rename($this->getInternalPath($path1),$this->getInternalPath($path2));
					}
				}elseif($storage1=$this->getStorage($path1) and $storage2=$this->getStorage($path2)){
					$tmpFile=$storage1->toTmpFile($this->getInternalPath($path1));
					$result=$storage2->fromTmpFile($tmpFile,$this->getInternalPath($path2));
					$storage1->unlink($this->getInternalPath($path1));
				}
				OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_post_rename, array( OC_Filesystem::signal_param_oldpath => $path1, OC_Filesystem::signal_param_newpath=>$path2));
				return $result;
			}
		}
	}
	public function copy($path1,$path2){
		if(OC_FileProxy::runPreProxies('copy',$path1,$path2) and $this->is_readable($path1) and OC_Filesystem::isValidPath($path2)){
			$run=true;
			OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_copy, array( OC_Filesystem::signal_param_oldpath => $path1 , OC_Filesystem::signal_param_newpath=>$path2, OC_Filesystem::signal_param_run => &$run));
			$exists=$this->file_exists($path2);
			if($run and !$exists){
				OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_create, array( OC_Filesystem::signal_param_path => $path2, OC_Filesystem::signal_param_run => &$run));
			}
			if($run){
				OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_write, array( OC_Filesystem::signal_param_path => $path2, OC_Filesystem::signal_param_run => &$run));
			}
			if($run){
				$mp1=$this->getMountPoint($path1);
				$mp2=$this->getMountPoint($path2);
				if($mp1==$mp2){
					if($storage=$this->getStorage($path1)){
						$result=$storage->copy($this->getInternalPath($path1),$this->getInternalPath($path2));
					}
				}elseif($storage1=$this->getStorage($path1) and $storage2=$this->getStorage($path2)){
					$tmpFile=$storage1->toTmpFile($this->getInternalPath($path1));
					$result=$storage2->fromTmpFile($tmpFile,$this->getInternalPath($path2));
				}
        OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_post_copy, array( OC_Filesystem::signal_param_oldpath => $path1 , OC_Filesystem::signal_param_newpath=>$path2));
				if(!$exists){
          OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_post_create, array( OC_Filesystem::signal_param_path => $path2));
				}
        OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_post_write, array( OC_Filesystem::signal_param_path => $path2));
				return $result;
			}
		}
	}
	public function fopen($path,$mode){
		$hooks=array();
		switch($mode){
			case 'r':
				$hooks[]='read';
				break;
			case 'r+':
			case 'w+':
			case 'x+':
			case 'a+':
				$hooks[]='read';
				$hooks[]='write';
				break;
			case 'w':
			case 'x':
			case 'a':
				$hooks[]='write';
				break;
			default:
				OC_Log::write('core','invalid mode ('.$mode.') for '.$path,OC_Log::ERROR);
		}

		return $this->basicOperation('fopen',$path,$hooks,$mode);
	}
	public function toTmpFile($path){
		if(OC_FileProxy::runPreProxies('toTmpFile',$path) and OC_Filesystem::isValidPath($path) and $storage=$this->getStorage($path)){
			OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_read, array( OC_Filesystem::signal_param_path => $path));
			return $storage->toTmpFile($this->getInternalPath($path));
		}
	}
	public function fromTmpFile($tmpFile,$path){
		if(OC_FileProxy::runPreProxies('copy',$tmpFile,$path) and OC_Filesystem::isValidPath($path) and $storage=$this->getStorage($path)){
			$run=true;
			$exists=$this->file_exists($path);
			if(!$exists){
				OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_create, array( OC_Filesystem::signal_param_path => $path, OC_Filesystem::signal_param_run => &$run));
			}
			if($run){
				OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_write, array( OC_Filesystem::signal_param_path => $path, OC_Filesystem::signal_param_run => &$run));
			}
			if($run){
				$result=$storage->fromTmpFile($tmpFile,$this->getInternalPath($path));
				if(!$exists){
					OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_post_create, array( OC_Filesystem::signal_param_path => $path));
				}
				OC_Hook::emit( OC_Filesystem::CLASSNAME, OC_Filesystem::signal_post_write, array( OC_Filesystem::signal_param_path => $path));
				return $result;
			}
		}
	}

	public function getMimeType($path){
		return $this->basicOperation('getMimeType',$path);
	}
	public function hash($type,$path){
		return $this->basicOperation('hash',$path,array('read'));
	}

	public function free_space($path='/'){
		return $this->basicOperation('free_space',$path);
	}

	/**
	 * abstraction for running most basic operations
	 * @param string $operation
	 * @param string #path
	 * @param array (optional) hooks
	 * @param mixed (optional) $extraParam
	 * @return mixed
	 */
	private function basicOperation($operation,$path,$hooks=array(),$extraParam=null){
		if(OC_FileProxy::runPreProxies($operation,$path, $extraParam) and OC_Filesystem::isValidPath($path) and $storage=$this->getStorage($path)){
			$interalPath=$this->getInternalPath($path);
			$run=true;
			foreach($hooks as $hook){
				if($hook!='read'){
					OC_Hook::emit( OC_Filesystem::CLASSNAME, $hook, array( OC_Filesystem::signal_param_path => $path, OC_Filesystem::signal_param_run => &$run));
				}else{
					OC_Hook::emit( OC_Filesystem::CLASSNAME, $hook, array( OC_Filesystem::signal_param_path => $path));
				}
			}
			if($run){
				if($extraParam){
					$result=$storage->$operation($interalPath,$extraParam);
				}else{
					$result=$storage->$operation($interalPath);
				}
				$result=OC_FileProxy::runPostProxies($operation,$path,$result);
				foreach($hooks as $hook){
					if($hook!='read'){
						OC_Hook::emit( OC_Filesystem::CLASSNAME, 'post_'.$hook, array( OC_Filesystem::signal_param_path => $path));
					}
				}
				return $result;
			}
		}
		return null;
	}
}