<?php

/**
 * Any feed must be a valid atom Feed document and conform to the guidelines below:
1.	Updated will be the latest time the folder or its contents was updated. If unknown by the underlying repository, it should be the current time.
2.	Author/name will be the CMIS property createdBy
3.	Title will be the CMIS property name
4.	App:edited will be the CMIS property lastModifiedDate
5.	Link with relation self will be generated to return the uri of the feed
 */

/**
 * At any point where an Atom document of type Entry is sent or returned, it must be a valid Atom Entry document and conform to the guidelines below:
1.	Atom:Title will be best efforts by the repository.  The repository should chose a property closest to Title.
2.	App:edited will be CMIS:lastModifiedDate
3.	Link with relation self will be the URI that returns the Atom Entry document
4.	Published will be CMIS:createdDate
5.	Atom:author will be CMIS:creator
6.	For content tags
7.	Documents with content
a.	Leverage the src attribute to point to the same link as stream
b.	The repository SHOULD populate the summary tag with text that at best efforts represents the documents.  For example, an HTML table containing the properties and their values for simple feed readers
i.	Other (Content-less document, Folder, Relationship, Type, etc) – best efforts at generating HTML text that represents the object.  That text would normally go into the summary tag, but since there is no content, goes in the content tag.
8.	If content src is specified, the summary SHOULD contain a text or html representation of the object.
9.	Links will be used to provide URIs to CMIS functionality
10.	Link relations may be omitted if the function is not allowed and that function would not show up on getAllowableActions.
11.	Links may be omitted if the repository does not support that capability
12.	All CMIS properties will be exposed in CMIS properties tag even if they are duplicated in an atom element

When POSTing an Atom Document, the atom fields take precedence over the CMIS property field for writeable properties.  For example, atom:title will overwrite cmis:name
 */

include_once CMIS_ATOM_LIB_FOLDER . 'RepositoryService.inc.php';
include_once CMIS_ATOM_LIB_FOLDER . 'NavigationService.inc.php';
include_once CMIS_ATOM_LIB_FOLDER . 'ObjectService.inc.php';
include_once CMIS_ATOM_LIB_FOLDER . 'VersioningService.inc.php';
include_once 'KT_cmis_atom_service_helper.inc.php';

// TODO consider changing all responses from the webservice layer to return PEAR errors or success results instead of the half/half we have at the moment.
//      the half/half occurred because on initial services PEAR Error seemed unnecessary, but it has proven useful for some of the newer functions :)

/**
 * AtomPub Service: folder
 */
class KT_cmis_atom_service_folder extends KT_cmis_atom_service {

    /**
     * Deals with GET actions for folders.
     * This includes children and tree/descendant listings as well as individual folder retrieval 
     */
    public function GET_action()
    {
        $RepositoryService = new RepositoryService();
        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];

        // TODO implement full path/node separation as with Alfresco - i.e. path requests come in on path/ and node requests come in on node/
        //      path request e.g.: Root Folder/DroppedDocuments
        //      node request e.g.: F1/children
        //      node request e.g.: F2
        if (urldecode($this->params[0]) == 'Root Folder')
        {
            $folderId = CMISUtil::encodeObjectId('Folder', 1);
            $folderName = urldecode($this->params[0]);
        }
        else if ($this->params[0] == 'path')
        {
            $ktapi =& KT_cmis_atom_service_helper::getKt();
            $folderId = KT_cmis_atom_service_helper::getFolderId($this->params, $ktapi);
        }
        else if (($this->params[1] == 'children') || ($this->params[1] == 'descendants'))
        {
            $folderId = $this->params[0];
            $ObjectService = new ObjectService(KT_cmis_atom_service_helper::getKt());
            $response = $ObjectService->getProperties($repositoryId, $folderId, false, false);
    
            if (PEAR::isError($response)) {
                $feed = KT_cmis_atom_service_helper::getErrorFeed($this, KT_cmis_atom_service::STATUS_SERVER_ERROR, $response->getMessage());
                $this->responseFeed = $feed;
                return null;
            }
            
            $folderName = $response['properties']['Name']['value'];
        }
        else {
            $folderId = $this->params[0];
        }

        if (!empty($this->params[1]) && (($this->params[1] == 'children') || ($this->params[1] == 'descendants')))
        {
            $NavigationService = new NavigationService(KT_cmis_atom_service_helper::getKt());
            $feed = $this->getFolderChildrenFeed($NavigationService, $repositoryId, $folderId, $folderName, $this->params[1]);
        }
        else
        {
            $ObjectService = new ObjectService(KT_cmis_atom_service_helper::getKt());
            $feed = KT_cmis_atom_service_helper::getObjectFeed($this, $ObjectService, $repositoryId, $folderId);
        }

        //Expose the responseFeed
        $this->responseFeed = $feed;
    }

    /**
     * Deals with folder service POST actions.
     * This includes creation/moving of both folders and documents.
     */
    public function POST_action()
    {
        $RepositoryService = new RepositoryService();
        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];

        // set default action, objectId and typeId
        $action = 'create'; 
        $objectId = null;
        $typeId = null;
        
        $folderId = $this->params[0];
        $title = KT_cmis_atom_service_helper::getAtomValues($this->parsedXMLContent['@children'], 'title');
        $summary = KT_cmis_atom_service_helper::getAtomValues($this->parsedXMLContent['@children'], 'summary');

        $properties = array('name' => $title, 'summary' => $summary);

        // determine whether this is a folder or a document action
        // document action create will have a content tag <atom:content> or <content> containing base64 encoding of the document
        // move action will have an existing id supplied as a parameter - not sure how this works yet as the CMIS clients we are
        // testing don't support move functionality at this time (2009/07/23) and so we are presuming the following format:
        // /folder/<folderId>/children/<objectId>
        // also possible that there will be an existing ObjectId property, try to cater for both until we know how it really works
        
        // check for existing object id as parameter in url
        if (isset($this->params[2]))
        {
            $action = 'move';
            $objectId = $this->params[2];
        }
        
        $cmisObjectProperties = KT_cmis_atom_service_helper::getCmisProperties($this->parsedXMLContent['@children']['cmis:object']);
        
        // check for existing object id as property of submitted object data
        if (!empty($cmisObjectProperties['ObjectId']))
        {
            $action = 'move';
            $objectId = $cmisObjectProperties['ObjectId'];
        }
        
        // TODO there may be more to do for the checking of an existing object.
        //      e.g. verifying that it does indeed exist, and throwing an exception if it does not:
        //      "If the objected property is present but not valid an exception will be thrown" (from CMIS specification)
        // NOTE this exception should be thrown in the service API code and not here.
        
        // determine type if object is being moved
        if (!is_null($objectId)) {
            CMISUtil::decodeObjectId($objectId, $typeId);
        }
        
        // now check for content stream
        $content = KT_cmis_atom_service_helper::getAtomValues($this->parsedXMLContent['@children'], 'content');        
        
        // TODO this will possibly need to change somewhat once Relationship Objects come into play.
        if ((($action == 'create') && (is_null($content))) || ($typeId == 'Folder')) {
            $type = 'folder';
        }
        else {
            $type = 'document';
        }

        $ObjectService = new ObjectService(KT_cmis_atom_service_helper::getKt());

        $success = false;
        $error = null;
        if ($action == 'create')
        {
            if ($type == 'folder')
                $newObjectId = $ObjectService->createFolder($repositoryId, ucwords($cmisObjectProperties['ObjectTypeId']), $properties, $folderId);
            else
                $newObjectId = $ObjectService->createDocument($repositoryId, ucwords($cmisObjectProperties['ObjectTypeId']), $properties, $folderId, $content);

            // check if returned Object Id is a valid CMIS Object Id
            CMISUtil::decodeObjectId($newObjectId, $typeId);
            if ($typeId != 'Unknown') $success = true;
            else $error = $newObjectId['message'];
        }
        else if ($action == 'move')
        {
            $response = $ObjectService->moveObject($repositoryId, $objectId, '', $folderId);
            
            if (!PEAR::isError($response)) $success = true;
            else $error = $response->getMessage();
            
            // same object as before
            $newObjectId = $objectId;
            $typeId = ucwords($type);
        }
        
        if ($success)
        {
            $this->setStatus(($action == 'create') ? self::STATUS_CREATED : self::STATUS_UPDATED);
            $feed = KT_cmis_atom_service_helper::getObjectFeed($this, $ObjectService, $repositoryId, $newObjectId, 'POST');
        }
        else {
            $feed = KT_cmis_atom_service_helper::getErrorFeed($this, self::STATUS_SERVER_ERROR, $error);
        }

        //Expose the responseFeed
        $this->responseFeed = $feed;
    }
    
    /**
     * Deals with DELETE actions for folders.
     * This includes deleting a single folder (with no content) and deleting an entire folder tree
     * 
     * @return 204 on success, 500 on error
     */
    public function DELETE_action()
    {
        // NOTE due to the way KnowledgeTree works with folders this is always going to call deleteTree.
        //      we COULD call deleteObject but when we delete a folder we expect to be trying to delete
        //      the folder and all content.
        
        $RepositoryService = new RepositoryService();
        $ObjectService = new ObjectService(KT_cmis_atom_service_helper::getKt());

        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];
        
        // attempt delete
        $response = $ObjectService->deleteTree($repositoryId, $this->params[0]);

        // error?
        if (PEAR::isError($response))
        {
            $feed = KT_cmis_atom_service_helper::getErrorFeed($this, self::STATUS_SERVER_ERROR, $response->getMessage());
           //Expose the responseFeed
            $this->responseFeed = $feed;
            return null;
        }
        // list of failed objects?
        if (is_array($response))
        {
            $this->setStatus(self::STATUS_SERVER_ERROR);
            
            $feed = new KT_cmis_atom_responseFeed_GET(CMIS_APP_BASE_URI);
            $feed->newField('title', 'Error: Failed to delete all objects in tree: ' . self::STATUS_SERVER_ERROR, $feed);
            
            foreach($response as $failed)
            {            
                $entry = $feed->newEntry();
                $objectElement = $feed->newElement('cmis:object');
                $propertiesElement = $feed->newElement('cmis:properties');
                $propElement = $feed->newElement('cmis:propertyId');
                $propElement->appendChild($feed->newAttr('cmis:name', 'ObjectId'));
                $feed->newField('cmis:value', $failed, $propElement);
                $propertiesElement->appendChild($propElement);
                $objectElement->appendChild($propertiesElement);
                $entry->appendChild($objectElement);
                $entry->appendChild($feed->newElement('cmis:terminator'));
            }
            
            $this->responseFeed = $feed;
            return null;
        }
        
        // success
        $this->setStatus(self::STATUS_NO_CONTENT);
    }

    /**
     * Retrieves children/descendants of the specified folder
     * TODO this currently only works in children mode, add descendants
     *
     * @param string $repositoryId
     * @param string $folderId folder id for which children/descendants are requested
     * @param string $feedType children or descendants
     * @return string CMIS AtomPub feed
     */
    private function getFolderChildrenFeed($NavigationService, $repositoryId, $folderId, $folderName, $feedType = 'children')
    {
        if ($feedType == 'children')
        {
            $entries = $NavigationService->getChildren($repositoryId, $folderId, false, false);
        }
        else if ($feedType == 'descendants')
        {
            $entries = $NavigationService->getDescendants($repositoryId, $folderId, false, false);
        }
        else
        {
            // error, we shouldn't be here, if we are then the wrong service/function was called
        }

        // $baseURI=NULL,$title=NULL,$link=NULL,$updated=NULL,$author=NULL,$id=NULL
        $feed = new KT_cmis_atom_responseFeed_GET(CMIS_APP_BASE_URI);
        $workspace = $feed->getWorkspace();
        
        $feed->newField('title', $folderName . ' ' . ucwords($feedType), $feed);
        
        // TODO dynamic?
        $feedElement = $feed->newField('author');
        $element = $feed->newField('name', 'System', $feedElement);
        $feed->appendChild($feedElement);
		
		// id
        $feed->newField('id', 'urn:uuid:' . $folderId . '-' . $feedType, $feed);

        // TODO get actual most recent update time, only use current if no other available
        $feed->newField('updated', KT_cmis_atom_service_helper::formatDatestamp(), $feed);

        $link = $feed->newElement('link');
        $link->appendChild($feed->newAttr('rel', 'self'));
        $link->appendChild($feed->newAttr('href', CMIS_APP_BASE_URI . $workspace . '/folder/' . $folderId . '/' . $feedType));
        $feed->appendChild($link);

        $link = $feed->newElement('link');
        $link->appendChild($feed->newAttr('rel', 'source'));
        $link->appendChild($feed->newAttr('href', CMIS_APP_BASE_URI . $workspace . '/folder/' . $folderId));
        $feed->appendChild($link);

        foreach($entries as $cmisEntry)
        {
            KT_cmis_atom_service_helper::createObjectEntry($feed, $cmisEntry, $folderName);
			
			// after each entry, add app:edited tag
           	$feed->newField('app:edited', KT_cmis_atom_service_helper::formatDatestamp(), $feed);
        }

        $feed->newField('cmis:hasMoreItems', 'false', $feed);

        return $feed;
    }

}

/**
 * AtomPub Service: types
 */
class KT_cmis_atom_service_types extends KT_cmis_atom_service {

    public function GET_action()
    {
        $RepositoryService = new RepositoryService();
        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];

        $types = $RepositoryService->getTypes($repositoryId);
        $type = ((empty($this->params[0])) ? 'all' : $this->params[0]);
        $feed = KT_cmis_atom_service_helper::getTypeFeed($type, $types);

        //Expose the responseFeed
        $this->responseFeed = $feed;
    }
    
}

/**
 * AtomPub Service: type
 */
class KT_cmis_atom_service_type extends KT_cmis_atom_service {

    public function GET_action()
    {
        $RepositoryService = new RepositoryService();

        // fetch repository id
        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];

        if (!isset($this->params[1])) {
        // For easier return in the wanted format, we call getTypes instead of getTypeDefinition.
        // Calling this with a single type specified returns an array containing the definition of
        // just the requested type.
        // NOTE could maybe be more efficient to call getTypeDefinition direct and then place in
        //      an array on this side?  or directly expose the individual entry response code and
        //      call directly from here rather than via getTypeFeed.
            $type = ucwords($this->params[0]);
            $types = $RepositoryService->getTypes($repositoryId, $type);
            $feed = KT_cmis_atom_service_helper::getTypeFeed($type, $types);
        }
        else {
        // TODO dynamic dates, as needed everywhere
        // NOTE children of types not yet implemented and we don't support any non-basic types at this time
            $feed = $this->getTypeChildrenFeed($this->params[1]);
        }

        //Expose the responseFeed
        $this->responseFeed=$feed;
    }

    /**
     * Retrieves a list of child types for the supplied type
     *
     * NOTE this currently returns a hard coded empty list, since we do not currently support child types
     * TODO make dynamic if/when we support checking for child types (we don't actually need to support child types themselves)
     *
     * @param string $type
     * @return string CMIS AtomPub feed
     */
    private function getTypeChildrenFeed()
    {
        //Create a new response feed
        // $baseURI=NULL,$title=NULL,$link=NULL,$updated=NULL,$author=NULL,$id=NULL
        $feed = new KT_cmis_atom_responseFeed_GET(CMIS_APP_BASE_URI);

        $feed->newField('title', 'Child Types of ' . ucwords($this->params[0]), $feed);
        $feed->newField('id', $this->params[0] . '-children', $feed);

        // TODO fetch child types - to be implemented when we support child types in the API

        // links
        $link = $feed->newElement('link');
        $link->appendChild($feed->newAttr('rel','first'));
        $link->appendChild($feed->newAttr('href', CMIS_APP_BASE_URI . 'type/' . $this->params[0] . '/' . $this->params[1] . '?pageNo=1&amp;pageSize=0'));
        $link->appendChild($feed->newAttr('type', 'application/atom+xml;type=feed'));

        $link = $feed->newElement('link');
        $link->appendChild($feed->newAttr('rel','last'));
        // TODO set page number correctly - to be done when we support paging the the API
        $link->appendChild($feed->newAttr('href', CMIS_APP_BASE_URI . 'type/' . $this->params[0] . '/' . $this->params[1] . '?pageNo=1&amp;pageSize=0'));
        $link->appendChild($feed->newAttr('type', 'application/atom+xml;type=feed'));

        $feed->newField('updated', KT_cmis_atom_service_helper::formatDatestamp(), $feed);
        $feed->newField('cmis:hasMoreItems', 'false', $feed);

        return $feed;
    }

}

/**
 * AtomPub Service: checkedout
 */
// NOTE this is always an empty document, underlying API code still to be implemented
class KT_cmis_atom_service_checkedout extends KT_cmis_atom_service {
    
    /**
     * Deals with GET actions for checkedout documents. 
     */
    public function GET_action()
    {
        $RepositoryService = new RepositoryService();
        $NavigationService = new NavigationService(KT_cmis_atom_service_helper::getKt());

        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];

        $checkedout = $NavigationService->getCheckedoutDocs($repositoryId);

        //Create a new response feed
        $feed = new KT_cmis_atom_responseFeed_GET(CMIS_APP_BASE_URI);
        
        $feed->newField('title', 'Checked out Documents', $feed);
		
        // TODO dynamic?
        $feedElement = $feed->newField('author');
        $element = $feed->newField('name', 'admin', $feedElement);
        $feed->appendChild($feedElement);
		
		$feed->appendChild($feed->newElement('id', 'urn:uuid:checkedout'));

        // TODO get actual most recent update time, only use current if no other available
        $feed->appendChild($feed->newElement('updated', KT_cmis_atom_service_helper::formatDatestamp()));
		
        foreach($checkedout as $document)
        {
            $entry = $feed->newEntry();
            $objectElement = $feed->newElement('cmis:object');
            $propertiesElement = $feed->newElement('cmis:properties');

            foreach($cmisEntry['properties'] as $propertyName => $property)
            {
                $propElement = $feed->newElement('cmis:' . $property['type']);
                $propElement->appendChild($feed->newAttr('cmis:name', $propertyName));
                $feed->newField('cmis:value', CMISUtil::boolToString($property['value']), $propElement);
                $propertiesElement->appendChild($propElement);
            }

            $objectElement->appendChild($propertiesElement);
            $entry->appendChild($objectElement);
        }

        $entry = null;
        $feed->newField('cmis:hasMoreItems', 'false', $entry, true);

        //Expose the responseFeed
        $this->responseFeed = $feed;
    }
    
    public function POST_action()
    {
        $RepositoryService = new RepositoryService();
        $VersioningService = new VersioningService(KT_cmis_atom_service_helper::getKt());
        $ObjectService = new ObjectService(KT_cmis_atom_service_helper::getKt());

        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];
        
        $cmisObjectProperties = KT_cmis_atom_service_helper::getCmisProperties($this->parsedXMLContent['@children']['cmis:object']);
                                                                                                      
        // check for existing object id as property of submitted object data
        if (empty($cmisObjectProperties['ObjectId']))
        {
            $feed = KT_cmis_atom_service_helper::getErrorFeed($this, self::STATUS_SERVER_ERROR, 'No object was specified for checkout');
            //Expose the responseFeed
            $this->responseFeed = $feed;
            return null;
        }
        
        $response = $VersioningService->checkOut($repositoryId, $cmisObjectProperties['ObjectId']);
        
        if (PEAR::isError($response))
        {
            $feed = KT_cmis_atom_service_helper::getErrorFeed($this, self::STATUS_SERVER_ERROR, 'No object was specified for checkout');
            //Expose the responseFeed
            $this->responseFeed = $feed;
            return null;
        }
        
        $this->setStatus(self::STATUS_CREATED);
        $feed = KT_cmis_atom_service_helper::getObjectFeed($this, $ObjectService, $repositoryId, $cmisObjectProperties['ObjectId'], 'POST');
//        $feed = KT_cmis_atom_service_helper::getObjectFeed($this, $ObjectService, $repositoryId, $newObjectId, 'POST');

        //Expose the responseFeed
        $this->responseFeed = $feed;
        
//        $checkedout = $NavigationService->getCheckedoutDocs($repositoryId);
//
//        //Create a new response feed
//        $feed = new KT_cmis_atom_responseFeed_GET(CMIS_APP_BASE_URI);
//        
//        $feed->newField('title', 'Checked out Documents', $feed);
//		
//        // TODO dynamic?
//        $feedElement = $feed->newField('author');
//        $element = $feed->newField('name', 'admin', $feedElement);
//        $feed->appendChild($feedElement);
//		
//		$feed->appendChild($feed->newElement('id', 'urn:uuid:checkedout'));
//
//        // TODO get actual most recent update time, only use current if no other available
//        $feed->appendChild($feed->newElement('updated', KT_cmis_atom_service_helper::formatDatestamp()));
//		
//        foreach($checkedout as $document)
//        {
//            $entry = $feed->newEntry();
//            $objectElement = $feed->newElement('cmis:object');
//            $propertiesElement = $feed->newElement('cmis:properties');
//
//            foreach($cmisEntry['properties'] as $propertyName => $property)
//            {
//                $propElement = $feed->newElement('cmis:' . $property['type']);
//                $propElement->appendChild($feed->newAttr('cmis:name', $propertyName));
//                $feed->newField('cmis:value', CMISUtil::boolToString($property['value']), $propElement);
//                $propertiesElement->appendChild($propElement);
//            }
//
//            $objectElement->appendChild($propertiesElement);
//            $entry->appendChild($objectElement);
//        }
//
//        $entry = null;
//        $feed->newField('cmis:hasMoreItems', 'false', $entry, true);
//
//        //Expose the responseFeed
//        $this->responseFeed = $feed;
    }

}

/**
 * AtomPub Service: document
 */
// TODO confirm that an error response is sent when a document has status "deleted"
class KT_cmis_atom_service_document extends KT_cmis_atom_service {

    /**
     * Deals with GET actions for documents.
     * This includes individual document retrieval 
     */
    public function GET_action()
    {
        $RepositoryService = new RepositoryService();
        $ObjectService = new ObjectService(KT_cmis_atom_service_helper::getKt());

        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];
        
        // determine whether we want the document entry feed or the actual physical document content.
        // this depends on $this->params[1]
        if (!empty($this->params[1]))
        {
            $this->getContentStream($ObjectService, $repositoryId);
            return null;
        }

        $feed = KT_cmis_atom_service_helper::getObjectFeed($this, $ObjectService, $repositoryId, $this->params[0]);

        //Expose the responseFeed
        $this->responseFeed = $feed;
    }
    
    /**
     * Deals with DELETE actions for documents.
     * This includes deletion of a specific version of a document (latest version) via deleteObject 
     * as well as deleteAllVersions
     * 
     * @return 204 on success, 500 on error
     */
    public function DELETE_action()
    {
        // NOTE due to the way KnowledgeTree works with documents this is always going to call deleteAllVersions.
        //      we do not have support for deleting only specific versions (this may be added in the future.)
        
        $RepositoryService = new RepositoryService();
        $VersioningService = new VersioningService(KT_cmis_atom_service_helper::getKt());

        $repositories = $RepositoryService->getRepositories();
        $repositoryId = $repositories[0]['repositoryId'];
        
        // attempt delete
        $response = $VersioningService->deleteAllVersions($repositoryId, $this->params[0]);

        // error?
        if (PEAR::isError($response))
        {
            $feed = KT_cmis_atom_service_helper::getErrorFeed($this, self::STATUS_SERVER_ERROR, $response->getMessage());
            //Expose the responseFeed
            $this->responseFeed = $feed;
            return null;
        }
        
        // success
        $this->setStatus(self::STATUS_NO_CONTENT);        
    }
    
    private function getContentStream(&$ObjectService, $repositoryId)
    {
        $response = $ObjectService->getProperties($repositoryId, $this->params[0], false, false);
        if (PEAR::isError($response)) {
            $feed = KT_cmis_atom_service_helper::getErrorFeed($this, KT_cmis_atom_service::STATUS_SERVER_ERROR, $response->getMessage());
            $this->responseFeed = $feed;
            return null;
        }
        
        // TODO also check If-Modified-Since?
//        $this->headers['If-Modified-Since'] => 2009-07-24 17:16:54

        $this->contentDownload = true;
        $eTag = md5($response['properties']['LastModificationDate']['value'] . $response['properties']['ContentStreamLength']['value']);
        
        if ($this->headers['If-None-Match'] == $eTag)
        {
            $this->setStatus(self::STATUS_NOT_MODIFIED);
            $this->contentDownload = false;
            return null;
        }
        
        $contentStream = $ObjectService->getContentStream($repositoryId, $this->params[0]);
        
        // headers specific to output
        $this->setEtag($eTag);
        $this->setHeader('Last-Modified', $response['properties']['LastModificationDate']['value']);

        if (!empty($response['properties']['ContentStreamMimeType']['value'])) {
    		$this->setHeader('Content-type', $response['properties']['ContentStreamMimeType']['value'] . ';charset=utf-8');
        }
        else {
    		$this->setHeader('Content-type', 'text/plain;charset=utf-8');
        }
        
        $this->setHeader('Content-Disposition', 'attachment;filename="' . $response['properties']['ContentStreamFilename']['value'] . '"');
		$this->setHeader('Content-Length', $response['properties']['ContentStreamLength']['value']);
        $this->output = $contentStream;
    }
    
}

?>