<?php
/**
 * eGroupWare API: VFS - WebDAV access using the new stream wrapper VFS interface
 *
 * Using the PEAR HTTP/WebDAV/Server/Filesystem class (which need to be installed!)
 *
 * @link http://www.egroupware.org
 * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
 * @package api
 * @subpackage vfs
 * @author Ralf Becker <RalfBecker-AT-outdoor-training.de>
 * @author Hartmut Holzgraefe <hartmut@php.net> original HTTP/WebDAV/Server/Filesystem class, of which some code is used
 * @version $Id$
 */

require_once('HTTP/WebDAV/Server/Filesystem.php');

/**
 * FileManger - WebDAV access using the new stream wrapper VFS interface
 *
 * Using the PEAR HTTP/WebDAV/Server/Filesystem class (which need to be installed!)
 *
 * @todo table to store properties
 * @todo filesystem class uses PEAR's System::find in COPY, which we dont require nor know if it works on custom stream wrappers
 */
class vfs_webdav_server extends HTTP_WebDAV_Server_Filesystem
{
	/**
	 * Realm of eGW's WebDAV server
	 *
	 */
	const REALM = 'eGroupWare WebDAV server';
	var $dav_powered_by = self::REALM;
	var $http_auth_realm = self::REALM;

	/**
	 * Base directory is the URL of our VFS root
	 *
	 * @var string
	 */
	var $base = egw_vfs::PREFIX;

	/**
	 * Debug level: 0 = nothing, 1 = function calls, 2 = more info, eg. complete $_SERVER array
	 *
	 * The debug messages are send to the apache error_log
	 *
	 * @var integer
	 */
	var $debug = 0;

	/**
	* Serve a webdav request
	*
	* Reimplemented to not check our vfs base path with realpath and connect to mysql DB
	*
	* @access public
	* @param  string
	*/
	function ServeRequest($base = false)
	{
		// special treatment for litmus compliance test
		// reply on its identifier header
		// not needed for the test itself but eases debugging
		if (isset($this->_SERVER['HTTP_X_LITMUS'])) {
			error_log("Litmus test ".$this->_SERVER['HTTP_X_LITMUS']);
			header("X-Litmus-reply: ".$this->_SERVER['HTTP_X_LITMUS']);
		}
		// let the base class do all the work
		HTTP_WebDAV_Server::ServeRequest();
	}

	/**
	* DELETE method handler
	*
	* @param  array  general parameter passing array
	* @return bool   true on success
	*/
	function DELETE($options)
	{
		$path = $this->base . $options['path'];

		if (!file_exists($path))
		{
			return '404 Not found';
		}

		if (is_dir($path))
		{

			/*$query = "DELETE FROM {$this->db_prefix}properties
			WHERE path LIKE '".$this->_slashify($options["path"])."%'";
			mysql_query($query); */

			// recursive delete the directory
			egw_vfs::remove($options['path']);
		}
		else
		{
			unlink($path);
		}
		/*$query = "DELETE FROM {$this->db_prefix}properties
		WHERE path = '$options[path]'";
		mysql_query($query);*/

		return '204 No Content';
	}

    /**
     * MKCOL method handler
     *
     * Reimplemented to NOT use dirname/basename, which has problems with utf-8 chars
     *
     * @param  array  general parameter passing array
     * @return bool   true on success
     */
    function MKCOL($options)
    {
        $path   = $this->_unslashify($this->base .$options["path"]);
        $parent = egw_vfs::dirname($path);
        $name   = egw_vfs::basename($path);

        if (!file_exists($parent)) {
            return "409 Conflict";
        }

        if (!is_dir($parent)) {
            return "403 Forbidden";
        }

        if ( file_exists($parent."/".$name) ) {
            return "405 Method not allowed";
        }

        if (!empty($this->_SERVER["CONTENT_LENGTH"])) { // no body parsing yet
            return "415 Unsupported media type";
        }

        $stat = mkdir($parent."/".$name, 0777);
        if (!$stat) {
            return "403 Forbidden";
        }

        return ("201 Created");
    }

	/**
     * COPY method handler
     *
     * @param  array  general parameter passing array
     * @return bool   true on success
     */
    function COPY($options, $del=false)
    {
        // TODO Property updates still broken (Litmus should detect this?)

        if (!empty($this->_SERVER["CONTENT_LENGTH"])) { // no body parsing yet
            return "415 Unsupported media type";
        }

        // no copying to different WebDAV Servers yet
        if (isset($options["dest_url"])) {
            return "502 bad gateway";
        }

        $source = $this->base .$options["path"];
        if (!file_exists($source)) return "404 Not found";

        if (is_dir($source)) { // resource is a collection
            switch ($options["depth"]) {
            case "infinity": // valid
                break;
            case "0": // valid for COPY only
                if ($del) { // MOVE?
                    return "400 Bad request";
                }
                break;
            case "1": // invalid for both COPY and MOVE
            default:
                return "400 Bad request";
            }
        }

        $dest         = $this->base . $options["dest"];
        $destdir      = dirname($dest);

        if (!file_exists($destdir) || !is_dir($destdir)) {
            return "409 Conflict";
        }

        $new          = !file_exists($dest);
        $existing_col = false;

        if (!$new) {
            if ($del && is_dir($dest)) {
                if (!$options["overwrite"]) {
                    return "412 precondition failed";
                }
                $dest .= basename($source);
                if (file_exists($dest)) {
                    $options["dest"] .= basename($source);
                } else {
                    $new          = true;
                    $existing_col = true;
                }
            }
        }

        if (!$new) {
            if ($options["overwrite"]) {
                $stat = $this->DELETE(array("path" => $options["dest"]));
                if (($stat{0} != "2") && (substr($stat, 0, 3) != "404")) {
                    return $stat;
                }
            } else {
                return "412 precondition failed";
            }
        }

        if ($del) {
            if (!rename($source, $dest)) {
                return "500 Internal server error";
            }
            $destpath = $this->_unslashify($options["dest"]);
/*
            if (is_dir($source)) {
                $query = "UPDATE {$this->db_prefix}properties
                                 SET path = REPLACE(path, '".$options["path"]."', '".$destpath."')
                               WHERE path LIKE '".$this->_slashify($options["path"])."%'";
                mysql_query($query);
            }

            $query = "UPDATE {$this->db_prefix}properties
                             SET path = '".$destpath."'
                           WHERE path = '".$options["path"]."'";
            mysql_query($query);
*/
        } else {
            if (is_dir($source) && $options['depth'] == 'infinity') {
            	$files = egw_vfs::find($source,array('depth' => true,'url' => true));	// depth=true: return dirs first, url=true: allow urls!
            } else {
                $files = array($source);
            }

            if (!is_array($files) || empty($files)) {
                return "500 Internal server error";
            }


            foreach ($files as $file) {
                if (is_dir($file)) {
                    $file = $this->_slashify($file);
                }

                $destfile = str_replace($source, $dest, $file);

                if (is_dir($file)) {
                    if (!is_dir($destfile)) {
                        // TODO "mkdir -p" here? (only natively supported by PHP 5)
                        if (!@mkdir($destfile)) {
                            return "409 Conflict";
                        }
                    }
                } else {
                    if (!@copy($file, $destfile)) {
                        return "409 Conflict";
                    }
                }
            }

/*
           $query = "INSERT INTO {$this->db_prefix}properties
                               SELECT *
                                 FROM {$this->db_prefix}properties
                                WHERE path = '".$options['path']."'";
*/
        }
        // adding Location header as shown in example in rfc2518 section 8.9.5
		header('Location: '.$this->base_uri.$options['dest']);

        return ($new && !$existing_col) ? "201 Created" : "204 No Content";
    }

    /**
	* Get properties for a single file/resource
	*
	* @param  string  resource path
	* @return array   resource properties
	*/
	function fileinfo($path)
	{
		// internally we require some url-encoding, as vfs_stream_wrapper uses URL's internally
		$path = str_replace(array('#','?'),array('%23','%3F'),$path);

		//error_log(__METHOD__."($path)");
		// map URI path to filesystem path
		$fspath = $this->base . $path;

		// create result array
		$info = array();
		// TODO remove slash append code when base class is able to do it itself
		$info['path']  = is_dir($fspath) ? $this->_slashify($path) : $path;

		// remove all urlencoding we need internally in EGw, HTTP_WebDAV_Server will add it's own!
		// rawurldecode does NOT touch +
		$info['path'] = rawurldecode($info['path']);

		$info['props'] = array();

		// no special beautified displayname here ...
		$info['props'][] = HTTP_WebDAV_Server::mkprop	('displayname', egw_vfs::basename(self::_unslashify($info['path'])));

		// creation and modification time
		$info['props'][] = HTTP_WebDAV_Server::mkprop	('creationdate',    filectime($fspath));
		$info['props'][] = HTTP_WebDAV_Server::mkprop	('getlastmodified', filemtime($fspath));

        // Microsoft extensions: last access time and 'hidden' status
        $info["props"][] = HTTP_WebDAV_Server::mkprop("lastaccessed",    fileatime($fspath));
        $info["props"][] = HTTP_WebDAV_Server::mkprop("ishidden",        egw_vfs::is_hidden($fspath));

		// type and size (caller already made sure that path exists)
		if (is_dir($fspath)) {
			// directory (WebDAV collection)
			$info['props'][] = HTTP_WebDAV_Server::mkprop	('resourcetype', array(
			 	HTTP_WebDAV_Server::mkprop('collection', '')));
			$info['props'][] = HTTP_WebDAV_Server::mkprop	('getcontenttype', 'httpd/unix-directory');
		} else {
			// plain file (WebDAV resource)
			$info['props'][] = HTTP_WebDAV_Server::mkprop	('resourcetype', '');
			if (egw_vfs::is_readable($path)) {
				$info['props'][] = HTTP_WebDAV_Server::mkprop	('getcontenttype', egw_vfs::mime_content_type($path));
			} else {
				error_log(__METHOD__."($path) $fspath is not readable!");
				$info['props'][] = HTTP_WebDAV_Server::mkprop	('getcontenttype', 'application/x-non-readable');
			}
			$info['props'][] = HTTP_WebDAV_Server::mkprop	('getcontentlength', filesize($fspath));
		}
		// generate etag from inode (sqlfs: fs_id), modification time and size
		$stat = stat($fspath);
		$info['props'][] = HTTP_WebDAV_Server::mkprop('getetag', '"'.$stat['ino'].':'.$stat['mtime'].':'.$stat['size'].'"');

/*		returning the supportedlock property causes Windows DAV provider and Konqueror to not longer work
		ToDo: return it only if explicitly requested ($options['props'])
		// supportedlock property
		$info['props'][] = HTTP_WebDAV_Server::mkprop('supportedlock','
      <D:lockentry>
       <D:lockscope><D:exclusive/></D:lockscope>
       <D:locktype><D:write/></D:lockscope>
      </D:lockentry>
      <D:lockentry>
       <D:lockscope><D:shared/></D:lockscope>
       <D:locktype><D:write/></D:lockscope>
      </D:lockentry>');
*/
		// ToDo: etag from inode and modification time

		//error_log(__METHOD__."($path) info=".array2string($info));
		return $info;
	}

	/**
	 * Which regular properties should be copied to different namespaces and names,
	 * because PROPPATCH stores them not as properties under their namespace and name,
	 * but simply sets the standard stat values instead.
	 *
	 * @var array stat-attr => array(array('ns'=>namespace, 'name'=>attribute-name)[, ...])
	 */
	public static $auto_props = array(
		'mtime' => array(
			array('ns' => 'urn:schemas-microsoft-com:', 'name' => 'Win32LastModifiedTime'),
			array('ns' => 'http://www.southrivertech.com/', 'name' => 'srt_modifiedtime'),
			array('ns' => 'http://www.southrivertech.com/', 'name' => 'getlastmodified'),
		),
		'ctime' => array(
			// no streamwrapper interface / php function to set the ctime currently
			//array('ns' => 'urn:schemas-microsoft-com:', 'name' => 'Win32CreationTime'),
			//array('ns' => 'http://www.southrivertech.com/', 'name' => 'srt_creationtime'),
		),
	);

	/**
	 * PROPFIND method handler
	 *
	 * Reimplemented to fetch all extra property of a PROPFIND request in one go.
	 *
	 * @param  array  general parameter passing array
	 * @param  array  return array for file properties
	 * @return bool   true on success
	 */
	function PROPFIND(&$options, &$files)
	{
		if (!parent::PROPFIND($options,$files))
		{
			return false;
		}
		$path2n = array();
		foreach($files['files'] as $n => $info)
		{
			// do NOT report /clientsync/.favorites/, as it fails
			if (strpos($info['path'],'/clientsync/.favorites/') === 0)
			{
				unset($files['files'][$n]);
				continue;
			}
			$path = $info['path'];
			if (!$n && $info['path'] != '/' && substr($info['path'],-1) == '/') $path = substr($info['path'],0,-1);

			// need to encode path again, as $info['path'] is NOT encoded, but egw_vfs::(stat|propfind) require it
			// otherwise pathes containing url special chars like ? or # will not stat
			$path = egw_vfs::encodePath($path);
			$path2n[$path] = $n;

			// adding some properties used instead of regular DAV times
			if (($stat = egw_vfs::stat($path)))
			{
				$fileprops =& $files['files'][$path2n[$path]]['props'];
				foreach(self::$auto_props as $attr => $props)
				{
					switch($attr)
					{
						case 'ctime':
						case 'mtime':
						case 'atime':
							$value = gmdate('D, d M Y H:i:s T',$stat[$attr]);
							break;

						default:
							continue 2;
					}
					foreach($props as $prop)
					{
						$prop['val'] = $value;
						$fileprops[] = $prop;
					}
				}
			}
		}
		if ($path2n && ($path2props = egw_vfs::propfind(array_keys($path2n),null)))
		{
			foreach($path2props as $path => $props)
			{
				$fileprops =& $files['files'][$path2n[$path]]['props'];
				foreach($props as $prop)
				{
					if ($prop['ns'] == egw_vfs::DEFAULT_PROP_NAMESPACE && $prop['name'][0] == '#')	// eGW's customfields
					{
						$prop['ns'] .= 'customfields/';
						$prop['name'] = substr($prop['name'],1);
					}
					$fileprops[] = $prop;
				}
			}
		}
		if ($this->debug) error_log(__METHOD__."() props=".array2string($files['files']));
		return true;
	}

 	/**
	 * Used eg. by get
	 *
	 * @todo replace all calls to _mimetype with egw_vfs::mime_content_type()
	 * @param string $path
	 * @return string
	 */
	function _mimetype($path)
	{
		return egw_vfs::mime_content_type($path);
	}

    /**
     * Check if path is readable by current user
     *
     * @param string $fspath
     * @return boolean
     */
    function _is_readable($fspath)
    {
    	return egw_vfs::is_readable($fspath);
    }

    /**
     * Check if path is writable by current user
     *
     * @param string $fspath
     * @return boolean
     */
    function _is_writable($fspath)
    {
    	return egw_vfs::is_writable($fspath);
    }

	/**
	 * PROPPATCH method handler
	 *
	 * The current version only allows Webdrive to set creation and modificaton dates.
	 * They are not stored as (arbitrary) WebDAV properties with their own namespace and name,
	 * but in the regular vfs attributes.
	 *
	 * @param  array  general parameter passing array
	 * @return bool   true on success
	 */
	function PROPPATCH(&$options)
	{
		$path = translation::convert($options['path'],'utf-8');

		foreach ($options['props'] as $key => $prop) {
			$attributes = array();
			switch($prop['ns'])
			{
				// allow Webdrive to set creation and modification time
				case 'http://www.southrivertech.com/':
					switch($prop['name'])
					{
						case 'srt_modifiedtime':
						case 'getlastmodified':
							egw_vfs::touch($path,strtotime($prop['val']));
							break;
						//case 'srt_creationtime':
							// no streamwrapper interface / php function to set the ctime currently
							//$attributes['created'] = strtotime($prop['val']);
							//break;
						default:
							if (!egw_vfs::proppatch($path,array($prop))) $options['props'][$key]['status'] = '403 Forbidden';
							break;
					}
					break;

				case 'DAV:':
					switch($prop['name'])
					{
						// allow netdrive to change the modification time
						case 'getlastmodified':
							egw_vfs::touch($path,strtotime($prop['val']));
							break;
						// not sure why, the filesystem example of the WebDAV class does it ...
						default:
							$options['props'][$key]['status'] = '403 Forbidden';
							break;
					}
					break;

				case 'urn:schemas-microsoft-com:':
					switch($prop['name'])
					{
						case 'Win32LastModifiedTime':
							egw_vfs::touch($path,strtotime($prop['val']));
							break;
						case 'Win32CreationTime':	// eg. "Wed, 14 Sep 2011 15:48:26 GMT"
						case 'Win32LastAccessTime':
						case 'Win32FileAttributes':	// not sure what that is, it was always "00000000"
						default:
							if (!egw_vfs::proppatch($path,array($prop))) $options['props'][$key]['status'] = '403 Forbidden';
							break;
					}
					break;

				case egw_vfs::DEFAULT_PROP_NAMESPACE.'customfields/':	// eGW's customfields
					$prop['ns'] = egw_vfs::DEFAULT_PROP_NAMESPACE;
					$prop['name'] = '#'.$prop['name'];
					// fall through
				default:
					if (!egw_vfs::proppatch($path,array($prop))) $options['props'][$key]['status'] = '403 Forbidden';
					break;
			}
			if ($this->debug) $props[] = '('.$prop['ns'].')'.$prop['name'].'='.$prop['val'];
		}
		if ($this->debug)
		{
			error_log(__METHOD__.": path=$options[path], props=".implode(', ',$props));
			if ($attributes) error_log(__METHOD__.": path=$options[path], set attributes=".str_replace("\n",' ',print_r($attributes,true)));
		}

		return '';	// this is as the filesystem example handler does it, no true or false ...
	}

	/**
	 * LOCK method handler
	 *
	 * @param  array  general parameter passing array
	 * @return bool   true on success
	 */
	function LOCK(&$options)
	{
		if ($this->debug) error_log(__METHOD__.'('.str_replace(array("\n",'    '),'',print_r($options,true)).')');
		// TODO recursive locks on directories not supported yet
		if (is_dir($this->base . $options['path']) && !empty($options['depth']))
		{
			return '409 Conflict';
		}
		$options['timeout'] = time()+300; // 5min. hardcoded

		// dont know why, but HTTP_WebDAV_Server passes the owner in D:href tags, which get's passed unchanged to checkLock/PROPFIND
		// that's wrong according to the standard and cadaver does not show it on discover --> strip_tags removes eventual tags
		if (($ret = egw_vfs::lock($options['path'],$options['locktoken'],$options['timeout'],strip_tags($options['owner']),
			$options['scope'],$options['type'],isset($options['update']))) && !isset($options['update']))
		{
			return $ret ? '200 OK' : '409 Conflict';
		}
		return $ret;
	}

	/**
	 * UNLOCK method handler
	 *
	 * @param  array  general parameter passing array
	 * @return bool   true on success
	 */
	function UNLOCK(&$options)
	{
		if ($this->debug) error_log(__METHOD__.'('.str_replace(array("\n",'    '),'',print_r($options,true)).')');
		return egw_vfs::unlock($options['path'],$options['token']) ? '204 No Content' : '409 Conflict';
	}

	/**
	 * checkLock() helper
	 *
	 * @param  string resource path to check for locks
	 * @return bool   true on success
	 */
	function checkLock($path)
	{
		return egw_vfs::checkLock($path);
	}

	/**
	 * GET method handler for directories
	 *
	 * Reimplemented to send content type header with charset
	 *
	 * @param  string  directory path
	 * @return void    function has to handle HTTP response itself
	 */
    function GetDir($fspath, &$options)
    {
		// add a content-type header to overwrite an existing default charset in apache (AddDefaultCharset directiv)
		header('Content-type: text/html; charset='.translation::charset());

		parent::GetDir($fspath, $options);
    }

	private $force_download = false;

	/**
	 * Constructor
	 *
	 * Reimplement to add a Content-Disposition header, if ?download is appended to the REQUEST_URI
	 */
	function __construct()
	{
		if ($_SERVER['REQUEST_METHOD'] == 'GET' && ($this->force_download = strpos($_SERVER['REQUEST_URI'],'?download')))
		{
			$_SERVER['REQUEST_URI'] = substr($_SERVER['REQUEST_URI'],0,$this->force_download);
		}
		parent::HTTP_WebDAV_Server();
	}

	/**
	 * GET method handler
	 *
	 * Reimplement to add a Content-Disposition header, if ?download is appended to the REQUEST_URI
	 *
	 * @param  array  parameter passing array
	 * @return bool   true on success
	 */
	function GET(&$options)
	{
		if (($ok = parent::GET($options)) && $this->force_download)
		{
			if(html::$user_agent == 'msie' && html::$ua_version < 9.0)
			{
				$attachment = '';
			}
			else
			{
				$attachment = ' attachment;';
			}
			header('Content-disposition:'.$attachment.' filename="'.egw_vfs::basename($options['path']).'"');
		}
		return $ok;
	}
}