* OLAT - Online Learning and Training<br>

* <p>

* <p>

* <p>

* <p>

* <p>

* Description:<br>

* This class handles several wiki's by storing them in a cache and also creates a new wikis.

* It handles also the file operation to persist the data in the wiki pages which are stored on the file

* system.

* <P>

* Initial Date: May 5, 2006 <br>

*

* @author guido

*/

  public static final String VIEW_COUNT = "view.count";

  public static final String MODIFY_AUTHOR = "modify.author";

  public static final String M_TIME = "mTime";

  public static final String INITIAL_AUTHOR = "initial.author";

  public static final String FORUM_KEY = "forum.key";

  public static final String VERSION = "version";

  public static final String C_TIME = "cTime";

  public static final String PAGENAME = "pagename";

  private static WikiManager instance = new WikiManager();

  public static final String WIKI_RESOURCE_FOLDER_NAME = "wiki";

  public static final String VERSION_FOLDER_NAME = "versions";

  public static final String WIKI_FILE_SUFFIX = "wp";

  public static final String WIKI_PROPERTIES_SUFFIX = "properties";

  public static final String UPDATE_COMMENT = "update.comment";

  OLog log = Tracing.createLoggerFor(this.getClass());

 

  //o_clusterNOK cache : 08.04.08/cg Not tested in cluster-mode

  CacheWrapper wikiCache;

  /**

   * return singleton

   */

  public static WikiManager getInstance() {

    return instance;

  }

 

 

  // ---- begin controller factory -----

  /** @param ureq

   * @param wControl

   * @param ores either an OlatResourcable of an repository entry or of an BusinessGroup

   * @param securityCallback a callback to evaluate the permissions

   * @param initialPageName opens the wiki with an certain page, default is the index page if null is passed

   * @param courseContext - a course context or null if used outside a course

   * @param courseNodeContext - a courseNode context or null if used outside a course

   * @param groupContext - a BusinessGroup or null if not used in group context

   */

  public WikiMainController createWikiMainController(UserRequest ureq, WindowControl wControl, OLATResourceable ores, WikiSecurityCallback securityCallback, String initialPageName) {

    return new WikiMainController(ureq, wControl, ores, securityCallback, initialPageName);

  }

 

  /**

   * brasato:::: to discuss, are two methods needed at all? probably not, unless there are cases to launch this controller without an ores known.

   * such as contentPackacking which requires only a fileroot (but this file directory depends on a ores in the end)

   *

   * create a wikiMaincontroller which disposes itself when the associated olatresourceable is disposed.

   */

  public Controller createWikiMainControllerDisposeOnOres(UserRequest ureq, WindowControl wControl, OLATResourceable ores, WikiSecurityCallback securityCallback, String initialPageName) {

    Controller controller = new WikiMainController(ureq, wControl, ores, securityCallback, initialPageName);

    OLATResourceableListeningWrapperController dwc = new OLATResourceableListeningWrapperController(ureq, wControl, ores, controller, ureq.getIdentity());

    return dwc;

  }

  // ---- end controller factory -----

  /**

   * @return the new created resource

   */

  public FileResource createWiki() {

    FileResource resource = new WikiResource();

    createFolders(resource);

    OLATResourceManager rm = OLATResourceManager.getInstance();

    OLATResource ores = rm.createOLATResourceInstance(resource);

    rm.saveOLATResource(ores);

    return resource;

  }

  private void createFolders(OLATResourceable ores) {

    long start = 0;

    if (log.isDebug()) {

      start = System.currentTimeMillis();

    }

    VFSContainer rootContainer = getWikiRootContainer(ores);

    VFSContainer unzippedDir = (VFSContainer) rootContainer.resolve(FileResourceManager.ZIPDIR);

    if (unzippedDir == null) { // check for _unzipped_ dir from imported wiki's

      if (rootContainer.createChildContainer(WIKI_RESOURCE_FOLDER_NAME) == null) throwError(ores);

      if (rootContainer.createChildContainer(WikiContainer.MEDIA_FOLDER_NAME) == null) throwError(ores);

      if (rootContainer.createChildContainer(VERSION_FOLDER_NAME) == null) throwError(ores);

    } else { // _unzipped_ dir found: move elements to wiki folder and delete

      // unzipped dir and zip files

      List files = unzippedDir.getItems();

      VFSContainer wikiCtn = rootContainer.createChildContainer(WIKI_RESOURCE_FOLDER_NAME);

      VFSContainer mediaCtn = rootContainer.createChildContainer(WikiContainer.MEDIA_FOLDER_NAME);

      if (rootContainer.createChildContainer(VERSION_FOLDER_NAME) == null) throwError(ores);

      if (wikiCtn == null) throwError(ores);

      // copy files to wiki and media folder

      for (Iterator iter = files.iterator(); iter.hasNext();) {

        VFSLeaf leaf = ((VFSLeaf) iter.next());

        if (leaf.getName().endsWith(WikiManager.WIKI_FILE_SUFFIX) || leaf.getName().endsWith(WikiManager.WIKI_PROPERTIES_SUFFIX)) {

          wikiCtn.copyFrom(leaf);

        } else {

          if (leaf.getName().contains(WikiManager.WIKI_FILE_SUFFIX+"-") || leaf.getName().contains(WikiManager.WIKI_PROPERTIES_SUFFIX+"-")) {

            leaf.delete(); // delete version history

          } else

          mediaCtn.copyFrom(leaf);

        }

      }

      unzippedDir.delete();

      List zipFiles = rootContainer.getItems(new VFSItemSuffixFilter(new String[] { "zip" }));

      // delete all zips

      for (Iterator iter = zipFiles.iterator(); iter.hasNext();) {

        VFSLeaf element = (VFSLeaf) iter.next();

        element.delete();

      }

      //reset forum key and author references keys back to default as users and forums may not exist

      List propertyLeafs = wikiCtn.getItems(new VFSItemSuffixFilter(new String[] { WikiManager.WIKI_PROPERTIES_SUFFIX }));

      for (Iterator iter = propertyLeafs.iterator(); iter.hasNext();) {

        VFSLeaf element = (VFSLeaf) iter.next();

        WikiPage page = Wiki.assignPropertiesToPage(element);

        page.setForumKey(0);

        page.setInitalAuthor(0);

        page.setModifyAuthor(0);

        page.setModificationTime(0);

        page.setViewCount(0);

        page.setVersion("0");

        page.setCreationTime(System.currentTimeMillis());

        saveWikiPageProperties(ores, page);

      }

    }

    if (log.isDebug()) {

      long end = System.currentTimeMillis();

      log.debug("creating folders and move files and updating properties to default values took: (milliseconds)"+(end-start));

    }

  }

  private void throwError(OLATResourceable ores) {

    throw new OLATRuntimeException(this.getClass(), "Unable to create wiki folder structure for resource: " + ores.getResourceableId(),

        null);

  }

    /**

     * @param ores

     * @return a wiki loaded from cache or the fileSystem

     */

  public Wiki getOrLoadWiki(final OLATResourceable ores) {

    final String wikiKey = OresHelper.createStringRepresenting(ores);

    //cluster_OK by guido

    if (wikiCache == null) {

      CoordinatorManager.getCoordinator().getSyncer().doInSync(ores, new SyncerExecutor() {

        public void  execute() {

          if (wikiCache == null) {

            wikiCache = CoordinatorManager.getCoordinator().getCacher().getOrCreateCache(this.getClass(), "wiki");

          }

        }

      });

    }

    Wiki wiki = (Wiki) wikiCache.get(wikiKey);

    if (wiki != null) {

      log.debug("loading wiki from cache. Ores: " + ores.getResourceableId());

      return wiki;

    }

    // No wiki in cache => load it form file-system

    CoordinatorManager.getCoordinator().getSyncer().doInSync(ores, new SyncerExecutor() {

      public void execute() {

        long start = 0;

        // wiki not in cache load form filesystem

        if (log.isDebug()) {

          log.debug("wiki not in cache. Loading wiki from filesystem. Ores: " + ores.getResourceableId());

          start = System.currentTimeMillis();

        }

        Wiki wiki = null;

        VFSContainer folder = getWikiContainer(ores, WIKI_RESOURCE_FOLDER_NAME);

        // wiki folder structure does not yet exists, but resource does. Create

        // wiki in group context

        if (folder == null) {

          // createWikiforExistingResource(ores);

          createFolders(ores);

          folder = getWikiContainer(ores, WIKI_RESOURCE_FOLDER_NAME);

        }

        // folders should be present, create the wiki

        wiki = new Wiki(getWikiRootContainer(ores));

        // filter for xyz.properties files

        List wikiLeaves = folder.getItems(new VFSItemSuffixFilter(new String[] { WikiManager.WIKI_PROPERTIES_SUFFIX }));

        for (Iterator iter = wikiLeaves.iterator(); iter.hasNext();) {

          VFSLeaf propertiesFile = (VFSLeaf) iter.next();

          WikiPage page = Wiki.assignPropertiesToPage(propertiesFile);

          if (page == null) {

            // broken pages get automatically cleaned from filesystem

            String contentFileToBeDeleted = (propertiesFile.getName().substring(0,

                propertiesFile.getName().length() - WikiManager.WIKI_PROPERTIES_SUFFIX.length()) + WikiManager.WIKI_FILE_SUFFIX);

            folder.resolve(contentFileToBeDeleted).delete();

            propertiesFile.delete();

            continue;

          }

          // index and menu page are loaded by default

          if (page.getPageName().equals(WikiPage.WIKI_INDEX_PAGE) || page.getPageName().equals(WikiPage.WIKI_MENU_PAGE)) {

            VFSLeaf leaf = (VFSLeaf) folder.resolve(page.getPageId() + "." + WikiManager.WIKI_FILE_SUFFIX);

            page.setContent(FileUtils.load(leaf.getInputStream(), "utf-8"));

          }

          // due to a bug we have to rename some pages that start with an non

          // ASCII lowercase letter

          String idOutOfFileName = propertiesFile.getName().substring(0, propertiesFile.getName().indexOf("."));

          if (!page.getPageId().equals(idOutOfFileName)) {

            // rename corrupt prop file

            propertiesFile.rename(page.getPageId() + "." + WikiManager.WIKI_PROPERTIES_SUFFIX);

            // load content and delete corrupt content file

            VFSLeaf contentFile = (VFSLeaf) folder.resolve(idOutOfFileName + "." + WikiManager.WIKI_FILE_SUFFIX);

            contentFile.rename(page.getPageId() + "." + WikiManager.WIKI_FILE_SUFFIX);

          }

          wiki.addPage(page);

        }

        // if index and menu page not present create the first page and save it

        if (wiki.getNumberOfPages() == 0) {

          WikiPage indexPage = new WikiPage(WikiPage.WIKI_INDEX_PAGE);

          WikiPage menuPage = new WikiPage(WikiPage.WIKI_MENU_PAGE);

          indexPage.setCreationTime(System.currentTimeMillis());

          wiki.addPage(indexPage);

          menuPage.setCreationTime(System.currentTimeMillis());

          menuPage.setContent("* [[Index]]\n* [[Index|Your link]]");

          wiki.addPage(menuPage);

          saveWikiPage(ores, indexPage, false, wiki);

          saveWikiPage(ores, menuPage, false, wiki);

        }

        // add pages internally used for displaying dynamic data, they are not

        // persisted

        WikiPage recentChangesPage = new WikiPage(WikiPage.WIKI_RECENT_CHANGES_PAGE);

        WikiPage a2zPage = new WikiPage(WikiPage.WIKI_A2Z_PAGE);

        wiki.addPage(recentChangesPage);

        wiki.addPage(a2zPage);

        // wikiCache.put(OresHelper.createStringRepresenting(ores), wiki);

        if (log.isDebug()) {

          long stop = System.currentTimeMillis();

          log.debug("loading of wiki from filessystem took (ms) " + (stop - start));

        }

        wikiCache.put(wikiKey, wiki);

      }

    });

    //at this point there will be something in the cache

    return (Wiki) wikiCache.get(wikiKey);

  }

   

  public DifferenceService getDiffService() {

    return new CookbookDifferenceService();

  }

  /**

   * persists a wiki page on the filesystem. It moves the recent page and the

   * metadata to the versions folder with the version on the tail and saves new

   * page with metadata to the wiki folder. Does not need to be synchronized as

   * editing is locked on page level by the

   *

   * @see WikiMainController

   * @param ores

   * @param page

   */

  protected void saveWikiPage(OLATResourceable ores, WikiPage page, boolean incrementVersion, Wiki wiki) {

    //cluster_OK by guido

    VFSContainer versionsContainer = getWikiContainer(ores, VERSION_FOLDER_NAME);

    VFSContainer wikiContentContainer = getWikiContainer(ores, WIKI_RESOURCE_FOLDER_NAME);

    // rename existing content file to version x and copy it to the version

    // container

    VFSItem item = wikiContentContainer.resolve(page.getPageId() + "." + WIKI_FILE_SUFFIX);

    if (item != null && incrementVersion) {

      if (page.getVersion() > 0) {

        versionsContainer.copyFrom(item);

        VFSItem copiedItem = versionsContainer.resolve(page.getPageId() + "." + WIKI_FILE_SUFFIX);

        String fileName = page.getPageId() + "." + WIKI_FILE_SUFFIX + "-" + page.getVersion();

        copiedItem.rename(fileName);

      }

      item.delete();

    }

    // rename existing meta file to version x and copy it to the version

    // container

    item = wikiContentContainer.resolve(page.getPageId() + "." + WIKI_PROPERTIES_SUFFIX);

    if (item != null && incrementVersion) {

      // TODO renaming and coping does not work. Bug?? felix fragen

      if (page.getVersion() > 0) {

        versionsContainer.copyFrom(item);

        VFSItem copiedItem = versionsContainer.resolve(page.getPageId() + "." + WIKI_PROPERTIES_SUFFIX);

        String fileName = page.getPageId() + "." + WIKI_PROPERTIES_SUFFIX + "-" + page.getVersion();

        copiedItem.rename(fileName);

      }

      item.delete();

    }

    // store recent content file

    VFSLeaf leaf = wikiContentContainer.createChildLeaf(page.getPageId() + "." + WIKI_FILE_SUFFIX);

    if(leaf == null) throw new AssertException("Tried to save wiki page with id ("+page.getPageId()+") and Olatresource: "+ores.getResourceableId()+" but page already existed!");

    FileUtils.save(leaf.getOutputStream(false), page.getContent(), "utf-8");

    // store recent properties file

    leaf = wikiContentContainer.createChildLeaf(page.getPageId() + "." + WIKI_PROPERTIES_SUFFIX);

    if (leaf == null) throw new AssertException("could not create file for wiki page "+page.getPageId()+", ores: "+ores.getResourceableTypeName()+":"+ores.getResourceableId()+", wikicontainer:"+wikiContentContainer);

    if (incrementVersion) page.incrementVersion();

    // update modification time

    if (!page.getContent().equals("")) page.setModificationTime(System.currentTimeMillis());

    Properties p = getPageProperties(page);

    try {

      OutputStream os = leaf.getOutputStream(false);

      p.store(os, "wiki page meta properties");

      os.close();

      // if (incrementVersion) page.incrementVersion();

    } catch (IOException e) {

      throw new OLATRuntimeException(WikiManager.class, "failed to save wiki page properties for page with id: " + page.getPageId() + " and olatresource: " + ores.getResourceableId(), e);

    }

    page.setViewCount(0); //reset view count of the page

   

    //update cache to inform all nodes about the change

    if (wikiCache!=null) {

      wikiCache.update(OresHelper.createStringRepresenting(ores), wiki);

    }

  }

  /**

   * delete a page completely by removing from the file system

   *

   * @param ores

   * @param page

   */

  protected void deleteWikiPage(OLATResourceable ores, WikiPage page) {

    String name = page.getPageName();

    // do not delete default pages

    if (name.equals(WikiPage.WIKI_INDEX_PAGE) || name.equals(WikiPage.WIKI_MENU_PAGE)) return;

    VFSContainer wikiContentContainer = getWikiContainer(ores, WIKI_RESOURCE_FOLDER_NAME);

    VFSContainer versionsContainer = getWikiContainer(ores, VERSION_FOLDER_NAME);

    //delete content and property file

    VFSItem item = wikiContentContainer.resolve(page.getPageId() + "." + WIKI_FILE_SUFFIX);

    if (item != null) item.delete();

    item = wikiContentContainer.resolve(page.getPageId() + "." + WIKI_PROPERTIES_SUFFIX);

    if (item != null) item.delete();

   

    //delete all version files of the page

    List leafs = versionsContainer.getItems(new VFSLeafFilter());

    if (leafs.size() > 0) {

      for (Iterator iter = leafs.iterator(); iter.hasNext();) {

        VFSLeaf leaf = (VFSLeaf) iter.next();

        String filename = leaf.getName();

        if (filename.startsWith(page.getPageId())) {

          leaf.delete();

        }

      }

    }

    log.audit("Deleted wiki page with name: " + page.getPageName() + " from resourcable id: "+ ores.getResourceableId());

    if (wikiCache!=null) {

      wikiCache.update(OresHelper.createStringRepresenting(ores), getOrLoadWiki(ores));

    }

  }

 

  /**

   * delete a whole wiki from the cache and the filesystem

   * @param ores

   */

  protected void deleteWiki(OLATResourceable ores) {

    if (wikiCache!=null) {

      wikiCache.remove(OresHelper.createStringRepresenting(ores));

    }

    OLATResourceManager.getInstance().deleteOLATResourceable(ores);

  }

  /**

   * @param ores

   * @param page

   */

  public void updateWikiPageProperties(OLATResourceable ores, WikiPage page) {

    saveWikiPageProperties(ores, page);

    if (wikiCache!=null) {

      wikiCache.update(OresHelper.createStringRepresenting(ores), getOrLoadWiki(ores));

    }

  }

  private void saveWikiPageProperties(OLATResourceable ores, WikiPage page) {

    VFSContainer wikiContentContainer = getWikiContainer(ores, WIKI_RESOURCE_FOLDER_NAME);

    VFSLeaf leaf = (VFSLeaf) wikiContentContainer.resolve(page.getPageId() + "." + WIKI_PROPERTIES_SUFFIX);

    if (leaf == null) leaf = wikiContentContainer.createChildLeaf(page.getPageId() + "." + WIKI_PROPERTIES_SUFFIX);

    Properties p = getPageProperties(page);

    try {

      p.store(leaf.getOutputStream(false), "wiki page meta properties");

    } catch (IOException e) {

      throw new OLATRuntimeException(WikiManager.class, "failed to save wiki page properties for page with id: " + page.getPageId() +" and olatresource: " + ores.getResourceableId(), e);

    }

  }

  /**

   * @param page

   * @return the fields of the page object as properties

   */

  private Properties getPageProperties(WikiPage page) {

    Properties p = new Properties();

    p.setProperty(PAGENAME, page.getPageName());

    p.setProperty(VERSION, String.valueOf(page.getVersion()));

    p.setProperty(FORUM_KEY, String.valueOf(page.getForumKey()));

    p.setProperty(INITIAL_AUTHOR, String.valueOf(page.getInitalAuthor()));

    p.setProperty(MODIFY_AUTHOR, String.valueOf(page.getModifyAuthor()));

    p.setProperty(C_TIME, String.valueOf(page.getCreationTime()));

    p.setProperty(VIEW_COUNT, String.valueOf(page.getViewCount()));

    p.setProperty(M_TIME, String.valueOf(page.getModificationTime()));

    p.setProperty(UPDATE_COMMENT, page.getUpdateComment());

    return p;

  }

  /**

   * @param pageName

   * @return

   */

  public static String generatePageId(String pageName) {

    try {

      String encoded = new String(Base64.encodeBase64(pageName.getBytes("utf-8")), "us-ascii");

      encoded = encoded.replace('/', '_'); //base64 can contain "/" so we have to replace them

      return encoded;

    } catch (UnsupportedEncodingException e) {

      throw new OLATRuntimeException(WikiManager.class, "Encoding UTF-8 not supported by your platform!", e);

    }

  }

  /**

   * @param ores

   * @param folderName

   * @return the Vfs container or null if not found

   */

  public VFSContainer getWikiContainer(OLATResourceable ores, String folderName) {

    VFSContainer wikiRootContainer = getWikiRootContainer(ores);

    return (VFSContainer) wikiRootContainer.resolve(folderName);

  }

 

  /**

   * Returns the root-container for certain OLAT-resourceable.

   * @param ores

   * @return

   */

  public VFSContainer getWikiRootContainer(OLATResourceable ores) {

    // Check if Resource is a BusinessGroup, because BusinessGroup-wiki's are stored at a different place

    if(log.isDebug()){

      log.debug("calculating wiki root container with ores id: "+ores.getResourceableId()+" and resourcable type name: "+ores.getResourceableTypeName());

    }

    if (isGroupContextWiki(ores)) {

      // Group Wiki

      return new OlatRootFolderImpl(getGroupWikiRelPath(ores), null);

    } else {

      // Repository Wiki

      return FileResourceManager.getInstance().getFileResourceRootImpl(ores);

    }

  }

 

  /**

   * Get Wiki-File-Path for certain BusinessGroup.

   * @param businessGroup

   * @return

   */

  private String getGroupWikiRelPath(OLATResourceable ores) {

    return "/cts/wikis/" + ores.getResourceableTypeName() + "/" + ores.getResourceableId();

  }

  /**

   * Return Media folder for uploading files.

   * @param ores

   * @return

   */

  public OlatRootFolderImpl getMediaFolder(OLATResourceable ores) {

    // Check if Resource is a BusinessGroup, because BusinessGroup-wiki's are stored at a different place

    if (isGroupContextWiki(ores)) {

      // Group Wiki

      return new OlatRootFolderImpl(getGroupWikiRelPath(ores) + "/" + WikiContainer.MEDIA_FOLDER_NAME, null);

    } else {

      // Repository Wiki 

      return new OlatRootFolderImpl("/repository/" + ores.getResourceableId() + "/" + WikiContainer.MEDIA_FOLDER_NAME,  null);

    }

  }

 

  /**

   * @return false if repository wiki or true if group only wiki

   */

  /**

   * @return false if repository wiki or true if group only wiki

   */

  protected boolean isGroupContextWiki(OLATResourceable ores) {

    return ores.getResourceableTypeName().equals(OresHelper.calculateTypeName(BusinessGroup.class));

  }

  /**

   * wiki subscription context for wikis in the course.

   * @param cenv

   * @param wikiCourseNode

   * @return

   */

  public static SubscriptionContext createTechnicalSubscriptionContextForCourse(CourseEnvironment cenv, WikiCourseNode wikiCourseNode) {

    return new SubscriptionContext(CourseModule.getCourseTypeName(), cenv.getCourseResourceableId(), wikiCourseNode.getIdent());

  }

 

}