Synnefo » Pithos Web Client

/*

 * Copyright 2011-2013 GRNET S.A. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or

 * without modification, are permitted provided that the following

 * conditions are met:

 *

 *   1. Redistributions of source code must retain the above

 *      copyright notice, this list of conditions and the following

 *      disclaimer.

 *

 *   2. Redistributions in binary form must reproduce the above

 *      copyright notice, this list of conditions and the following

 *      disclaimer in the documentation and/or other materials

 *      provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 *

 * The views and conclusions contained in the software and

 * documentation are those of the authors and should not be

 * interpreted as representing official policies, either expressed

 * or implied, of GRNET S.A.

 */

package gr.grnet.pithos.web.client;

import com.google.gwt.core.client.EntryPoint;

import com.google.gwt.core.client.GWT;

import com.google.gwt.core.client.JsArrayString;

import com.google.gwt.core.client.Scheduler;

import com.google.gwt.core.client.Scheduler.RepeatingCommand;

import com.google.gwt.core.client.Scheduler.ScheduledCommand;

import com.google.gwt.event.dom.client.ClickEvent;

import com.google.gwt.event.dom.client.ClickHandler;

import com.google.gwt.event.logical.shared.ResizeEvent;

import com.google.gwt.event.logical.shared.ResizeHandler;

import com.google.gwt.http.client.Response;

import com.google.gwt.http.client.URL;

import com.google.gwt.i18n.client.DateTimeFormat;

import com.google.gwt.i18n.client.Dictionary;

import com.google.gwt.i18n.client.TimeZone;

import com.google.gwt.resources.client.ClientBundle;

import com.google.gwt.resources.client.CssResource;

import com.google.gwt.resources.client.ImageResource;

import com.google.gwt.resources.client.ImageResource.ImageOptions;

import com.google.gwt.user.client.*;

import com.google.gwt.user.client.ui.*;

import com.google.gwt.view.client.SelectionChangeEvent;

import com.google.gwt.view.client.SelectionChangeEvent.Handler;

import com.google.gwt.view.client.SingleSelectionModel;

import gr.grnet.pithos.web.client.catalog.UpdateUserCatalogs;

import gr.grnet.pithos.web.client.catalog.UserCatalogs;

import gr.grnet.pithos.web.client.commands.UploadFileCommand;

import gr.grnet.pithos.web.client.foldertree.*;

import gr.grnet.pithos.web.client.grouptree.Group;

import gr.grnet.pithos.web.client.grouptree.GroupTreeView;

import gr.grnet.pithos.web.client.grouptree.GroupTreeViewModel;

import gr.grnet.pithos.web.client.mysharedtree.MysharedTreeView;

import gr.grnet.pithos.web.client.mysharedtree.MysharedTreeViewModel;

import gr.grnet.pithos.web.client.othersharedtree.OtherSharedTreeView;

import gr.grnet.pithos.web.client.othersharedtree.OtherSharedTreeViewModel;

import gr.grnet.pithos.web.client.rest.*;

import org.apache.http.HttpStatus;

import java.util.*;

/**

 * Entry point classes define <code>onModuleLoad()</code>.

 */

public class Pithos implements EntryPoint, ResizeHandler {

    private static final boolean IsLOGEnabled = false;

    public static final boolean IsDetailedHTTPLOGEnabled = true;

    public static final boolean IsFullResponseBodyLOGEnabled = true;

    public static final Set<String> HTTPHeadersToIgnoreInLOG = new HashSet<String>();

    static {

        HTTPHeadersToIgnoreInLOG.add(Const.HTTP_HEADER_CONNECTION);

        HTTPHeadersToIgnoreInLOG.add(Const.HTTP_HEADER_DATE);

        HTTPHeadersToIgnoreInLOG.add(Const.HTTP_HEADER_KEEP_ALIVE);

        HTTPHeadersToIgnoreInLOG.add(Const.HTTP_HEADER_SERVER);

        HTTPHeadersToIgnoreInLOG.add(Const.HTTP_HEADER_VARY);

        HTTPHeadersToIgnoreInLOG.add(Const.IF_MODIFIED_SINCE);

    }

    public static final Configuration config = GWT.create(Configuration.class);

    public static final String CONFIG_API_PATH = getFromOtherPropertiesOrDefaultString("STORAGE_API_URL", config.apiPath());

    static {

        LOG("CONFIG_API_PATH = ", CONFIG_API_PATH);

    }

    public static final Dictionary otherProperties = Dictionary.getDictionary(Const.OTHER_PROPERTIES);

    public static String getFromOtherPropertiesOrNull(String key) {

        try {

            return otherProperties.get(key);

        }

        catch(Exception e) {

            LOGError(e);

            return null;

        }

    }

    public static String getFromOtherPropertiesOrDefaultString(String key, String dflt) {

        try {

            return otherProperties.get(key);

        }

        catch(Exception e) {

            return dflt;

        }

    }

    public static final String OTHERPROPS_STORAGE_API_URL = getFromOtherPropertiesOrNull("STORAGE_API_URL");

    public static final String OTHERPROPS_USER_CATALOGS_API_URL = getFromOtherPropertiesOrNull("USER_CATALOGS_API_URL");

    static {

        LOG("STORAGE_API_URL = ", OTHERPROPS_STORAGE_API_URL);

        LOG("USER_CATALOGS_API_URL = ", OTHERPROPS_USER_CATALOGS_API_URL);

    }

    public static final String STORAGE_API_URL;

    static {

        if(OTHERPROPS_STORAGE_API_URL != null) {

            STORAGE_API_URL = OTHERPROPS_STORAGE_API_URL;

        }

        else if(CONFIG_API_PATH != null) {

            STORAGE_API_URL = CONFIG_API_PATH;

        }

        else {

            throw new RuntimeException("Unknown STORAGE_API_URL");

        }

    }

    public static final String USER_CATALOGS_API_URL;

    static {

        if(OTHERPROPS_USER_CATALOGS_API_URL != null) {

            USER_CATALOGS_API_URL = OTHERPROPS_USER_CATALOGS_API_URL;

        }

        else if(OTHERPROPS_STORAGE_API_URL != null) {

            throw new RuntimeException("STORAGE_API_URL is defined but USER_CATALOGS_API_URL is not");

        }

        else {

            // https://server.com/v1/ --> https://server.com

            String url = CONFIG_API_PATH;

            url = Helpers.stripTrailing(url, "/");

            url = Helpers.upToIncludingLastPart(url, "/");

            url = Helpers.stripTrailing(url, "/");

            url = url + "/user_catalogs";

            USER_CATALOGS_API_URL = url;

            LOG("USER_CATALOGS_API_URL = ", USER_CATALOGS_API_URL);

        }

    }

    public interface Style extends CssResource {

        String commandAnchor();

        String statistics();

        @ClassName("gwt-HTML")

        String html();

        String uploadAlert();

        String uploadAlertLink();

        String uploadAlertProgress();

        String uploadAlertPercent();

        String uploadAlertClose();

    }

    public interface Resources extends ClientBundle {

        @Source("Pithos.css")

        Style pithosCss();

        @Source("gr/grnet/pithos/resources/close-popup.png")

        ImageResource closePopup();

    }

    public static Resources resources = GWT.create(Resources.class);

    /**

     * Instantiate an application-level image bundle. This object will provide

     * programmatic access to all the images needed by widgets.

     */

    static Images images = (Images) GWT.create(Images.class);

    public String getUserID() {

        return userID;

    }

    public UserCatalogs getUserCatalogs() {

        return userCatalogs;

    }

    public String getCurrentUserDisplayNameOrID() {

        final String displayName = userCatalogs.getDisplayName(getUserID());

        return displayName == null ? getUserID() : displayName;

    }

    public boolean hasDisplayNameForUserID(String userID) {

        return userCatalogs.getDisplayName(userID) != null;

    }

    public boolean hasIDForUserDisplayName(String userDisplayName) {

        return userCatalogs.getID(userDisplayName) != null;

    }

    public String getDisplayNameForUserID(String userID) {

        return userCatalogs.getDisplayName(userID);

    }

    public String getIDForUserDisplayName(String userDisplayName) {

        return userCatalogs.getID(userDisplayName);

    }

    public List<String> getDisplayNamesForUserIDs(List<String> userIDs) {

        if(userIDs == null) {

            userIDs = new ArrayList<String>();

        }

        final List<String> userDisplayNames = new ArrayList<String>();

        for(String userID : userIDs) {

            final String displayName = getDisplayNameForUserID(userID);

            userDisplayNames.add(displayName);

        }

        return userDisplayNames;

    }

    public List<String> filterUserIDsWithUnknownDisplayName(Collection<String> userIDs) {

        if(userIDs == null) {

            userIDs = new ArrayList<String>();

        }

        final List<String> filtered = new ArrayList<String>();

        for(String userID : userIDs) {

            if(!this.userCatalogs.hasID(userID)) {

                filtered.add(userID);

            }

        }

        return filtered;

    }

    public void setAccount(AccountResource acct) {

        account = acct;

    }

    public AccountResource getAccount() {

        return account;

    }

    public void updateFolder(Folder f, boolean showfiles, Command callback, final boolean openParent) {

        folderTreeView.updateFolder(f, showfiles, callback, openParent);

    }

    public void updateGroupNode(Group group) {

        groupTreeView.updateGroupNode(group);

    }

    public void updateMySharedRoot() {

        mysharedTreeView.updateRoot();

    }

    public void updateSharedFolder(Folder f, boolean showfiles, Command callback) {

        mysharedTreeView.updateFolder(f, showfiles, callback);

    }

    public void updateSharedFolder(Folder f, boolean showfiles) {

        updateSharedFolder(f, showfiles, null);

    }

    public void updateOtherSharedFolder(Folder f, boolean showfiles, Command callback) {

        otherSharedTreeView.updateFolder(f, showfiles, callback);

    }

    public MysharedTreeView getMySharedTreeView() {

        return mysharedTreeView;

    }

    /**

     * An aggregate image bundle that pulls together all the images for this

     * application into a single bundle.

     */

    public interface Images extends TopPanel.Images, FileList.Images, ToolsMenu.Images {

        @Source("gr/grnet/pithos/resources/document.png")

        ImageResource folders();

        @Source("gr/grnet/pithos/resources/advancedsettings.png")

        @ImageOptions(width = 32, height = 32)

        ImageResource tools();

    }

    private Throwable error;

    /**

     * The Application Clipboard implementation;

     */

    private Clipboard clipboard = new Clipboard();

    /**

     * The top panel that contains the menu bar.

     */

    private TopPanel topPanel;

    /**

     * The panel that contains the various system messages.

     */

    private MessagePanel messagePanel = new MessagePanel(this, Pithos.images);

    /**

     * The bottom panel that contains the status bar.

     */

    StatusPanel statusPanel = null;

    /**

     * The file list widget.

     */

    private FileList fileList;

    /**

     * The tab panel that occupies the right side of the screen.

     */

    private VerticalPanel inner = new VerticalPanel();

    /**

     * The split panel that will contain the left and right panels.

     */

    private HorizontalSplitPanel splitPanel = new HorizontalSplitPanel();

    /**

     * The currently selected item in the application, for use by the Edit menu

     * commands. Potential types are Folder, File, User and Group.

     */

    private Object currentSelection;

    public HashMap<String, String> userFullNameMap = new HashMap<String, String>();

    /**

     * The ID that uniquely identifies the user in Pithos+.

     * Currently this is a UUID. It used to be the user's email.

     */

    private String userID = null;

    /**

     * Holds mappings from user UUIDs to emails and vice-versa.

     */

    private UserCatalogs userCatalogs = new UserCatalogs();

    /**

     * The authentication token of the current user.

     */

    private String userToken;

    VerticalPanel trees;

    SingleSelectionModel<Folder> folderTreeSelectionModel;

    FolderTreeViewModel folderTreeViewModel;

    FolderTreeView folderTreeView;

    SingleSelectionModel<Folder> mysharedTreeSelectionModel;

    MysharedTreeViewModel mysharedTreeViewModel;

    MysharedTreeView mysharedTreeView = null;

    protected SingleSelectionModel<Folder> otherSharedTreeSelectionModel;

    OtherSharedTreeViewModel otherSharedTreeViewModel;

    OtherSharedTreeView otherSharedTreeView = null;

    GroupTreeViewModel groupTreeViewModel;

    GroupTreeView groupTreeView;

    TreeView selectedTree;

    protected AccountResource account;

    Folder trash;

    List<Composite> treeViews = new ArrayList<Composite>();

    @SuppressWarnings("rawtypes")

    List<SingleSelectionModel> selectionModels = new ArrayList<SingleSelectionModel>();

    public Button upload;

    private HTML numOfFiles;

    private Toolbar toolbar;

    private FileUploadDialog fileUploadDialog = new FileUploadDialog(this);

    UploadAlert uploadAlert;

    Date lastModified;

    @Override

    public void onModuleLoad() {

        if(parseUserCredentials()) {

            initialize();

        }

    }

    static native void __ConsoleLog(String message) /*-{

      try { console.log(message); } catch (e) {}

    }-*/;

    public static void LOGError(Throwable error, StringBuilder sb) {

        if(!isLOGEnabled()) { return; }

        sb.append("\nException: [" + error.toString().replace("\n", "\n  ") + "]");

        Throwable cause = error.getCause();

        if(cause != null) {

            sb.append("\nCauses:\n");

            while(cause != null) {

                sb.append("  ");

                sb.append("[" + cause.toString().replace("\n", "\n  ")  + "]");

                sb.append("\n");

                cause = cause.getCause();

            }

        }

        else {

            sb.append("\n");

        }

        StackTraceElement[] stackTrace = error.getStackTrace();

        sb.append("Stack trace (" + stackTrace.length + " elements):\n");

        for(int i = 0; i < stackTrace.length; i++) {

            StackTraceElement errorElem = stackTrace[i];

            sb.append("  [" + i + "] ");

            sb.append(errorElem.toString());

            sb.append("\n");

        }

    }

    public static void LOGError(Throwable error) {

        if(!isLOGEnabled()) { return; }

        final StringBuilder sb = new StringBuilder();

        LOGError(error, sb);

        if(sb.length() > 0) {

            __ConsoleLog(sb.toString());

        }

    }

    public static boolean isLOGEnabled() {

        return IsLOGEnabled;

    }

    public static void LOG(Object ...args) {

        if(!isLOGEnabled()) { return; }

        final StringBuilder sb = new StringBuilder();

        for(Object arg : args) {

            if(arg instanceof Throwable) {

                LOGError((Throwable) arg, sb);

            }

            else {

                sb.append(arg);

            }

        }

        if(sb.length() > 0) {

            __ConsoleLog(sb.toString());

        }

    }

    private void initialize() {

        userCatalogs.updateWithIDAndName("*", "All Pithos users");

        lastModified = new Date(); //Initialize if-modified-since value with now.

        resources.pithosCss().ensureInjected();

        boolean bareContent = Window.Location.getParameter("noframe") != null;

        String contentWidth = bareContent ? Const.PERCENT_100 : Const.PERCENT_75;

        VerticalPanel outer = new VerticalPanel();

        outer.setWidth(Const.PERCENT_100);

        if(!bareContent) {

            outer.addStyleName("pithos-outer");

        }

        if(!bareContent) {

            topPanel = new TopPanel(this, Pithos.images);

            topPanel.setWidth(Const.PERCENT_100);

            outer.add(topPanel);

            outer.setCellHorizontalAlignment(topPanel, HasHorizontalAlignment.ALIGN_CENTER);

        }

        messagePanel.setVisible(false);

        outer.add(messagePanel);

        outer.setCellHorizontalAlignment(messagePanel, HasHorizontalAlignment.ALIGN_CENTER);

        outer.setCellVerticalAlignment(messagePanel, HasVerticalAlignment.ALIGN_MIDDLE);

        HorizontalPanel header = new HorizontalPanel();

        header.addStyleName("pithos-header");

        header.setWidth(contentWidth);

        if(bareContent) {

            header.addStyleName("pithos-header-noframe");

        }

        upload = new Button("Upload", new ClickHandler() {

            @Override

            public void onClick(ClickEvent event) {

                if(getSelection() != null) {

                    new UploadFileCommand(Pithos.this, null, getSelection()).execute();

                }

            }

        });

        upload.addStyleName("pithos-uploadButton");

        header.add(upload);

        header.setCellHorizontalAlignment(upload, HasHorizontalAlignment.ALIGN_LEFT);

        header.setCellVerticalAlignment(upload, HasVerticalAlignment.ALIGN_MIDDLE);

        toolbar = new Toolbar(this);

        header.add(toolbar);

        header.setCellHorizontalAlignment(toolbar, HasHorizontalAlignment.ALIGN_CENTER);

        header.setCellVerticalAlignment(toolbar, HasVerticalAlignment.ALIGN_MIDDLE);

        HorizontalPanel folderStatistics = new HorizontalPanel();

        folderStatistics.addStyleName("pithos-folderStatistics");

        numOfFiles = new HTML();

        folderStatistics.add(numOfFiles);

        folderStatistics.setCellVerticalAlignment(numOfFiles, HasVerticalAlignment.ALIGN_MIDDLE);

        HTML numOfFilesLabel = new HTML(" Files");

        folderStatistics.add(numOfFilesLabel);

        folderStatistics.setCellVerticalAlignment(numOfFilesLabel, HasVerticalAlignment.ALIGN_MIDDLE);

        header.add(folderStatistics);

        header.setCellHorizontalAlignment(folderStatistics, HasHorizontalAlignment.ALIGN_RIGHT);

        header.setCellVerticalAlignment(folderStatistics, HasVerticalAlignment.ALIGN_MIDDLE);

        header.setCellWidth(folderStatistics, "40px");

        outer.add(header);

        outer.setCellHorizontalAlignment(header, HasHorizontalAlignment.ALIGN_CENTER);

        // Inner contains the various lists

        inner.sinkEvents(Event.ONCONTEXTMENU);

        inner.setWidth(Const.PERCENT_100);

        folderTreeSelectionModel = new SingleSelectionModel<Folder>();

        folderTreeSelectionModel.addSelectionChangeHandler(new SelectionChangeEvent.Handler() {

            @Override

            public void onSelectionChange(SelectionChangeEvent event) {

                if(folderTreeSelectionModel.getSelectedObject() != null) {

                    deselectOthers(folderTreeView, folderTreeSelectionModel);

                    applyPermissions(folderTreeSelectionModel.getSelectedObject());

                    Folder f = folderTreeSelectionModel.getSelectedObject();

                    updateFolder(f, true, new Command() {

                        @Override

                        public void execute() {

                            updateStatistics();

                        }

                    }, true);

                    showRelevantToolbarButtons();

                }

                else {

                    if(getSelectedTree().equals(folderTreeView)) {

                        setSelectedTree(null);

                    }

                    if(getSelectedTree() == null) {

                        showRelevantToolbarButtons();

                    }

                }

            }

        });

        selectionModels.add(folderTreeSelectionModel);

        folderTreeViewModel = new FolderTreeViewModel(this, folderTreeSelectionModel);

        folderTreeView = new FolderTreeView(folderTreeViewModel);

        treeViews.add(folderTreeView);

        fileList = new FileList(this, images);

        inner.add(fileList);

        trees = new VerticalPanel();

        trees.setWidth(Const.PERCENT_100);

        // Add the left and right panels to the split panel.

        splitPanel.setLeftWidget(trees);

        FlowPanel right = new FlowPanel();

        right.getElement().setId("rightPanel");

        right.add(inner);

        splitPanel.setRightWidget(right);

        splitPanel.setSplitPosition("219px");

        splitPanel.setSize(Const.PERCENT_100, Const.PERCENT_100);

        splitPanel.addStyleName("pithos-splitPanel");

        splitPanel.setWidth(contentWidth);

        outer.add(splitPanel);

        outer.setCellHorizontalAlignment(splitPanel, HasHorizontalAlignment.ALIGN_CENTER);

        if(!bareContent) {

            statusPanel = new StatusPanel();

            statusPanel.setWidth(Const.PERCENT_100);

            outer.add(statusPanel);

            outer.setCellHorizontalAlignment(statusPanel, HasHorizontalAlignment.ALIGN_CENTER);

        }

        else {

            splitPanel.addStyleName("pithos-splitPanel-noframe");

        }

        // Hook the window resize event, so that we can adjust the UI.

        Window.addResizeHandler(this);

        // Clear out the window's built-in margin, because we want to take

        // advantage of the entire client area.

        Window.setMargin("0px");

        // Finally, add the outer panel to the RootPanel, so that it will be

        // displayed.

        RootPanel.get().add(outer);

        // Call the window resized handler to get the initial sizes setup. Doing

        // this in a deferred command causes it to occur after all widgets'

        // sizes have been computed by the browser.

        Scheduler.get().scheduleIncremental(new RepeatingCommand() {

            @Override

            public boolean execute() {

                if(!isCloudbarReady()) {

                    return true;

                }

                onWindowResized(Window.getClientHeight());

                return false;

            }

        });

        Scheduler.get().scheduleDeferred(new ScheduledCommand() {

            @Override

            public void execute() {

                LOG("Pithos::initialize() Calling Pithos::fetchAccount()");

                fetchAccount(new Command() {

                    @Override

                    public void execute() {

                        if(!account.hasHomeContainer()) {

                            createHomeContainer(account, this);

                        }

                        else if(!account.hasTrashContainer()) {

                            createTrashContainer(this);

                        }

                        else {

                            for(Folder f : account.getContainers()) {

                                if(f.getName().equals(Const.TRASH_CONTAINER)) {

                                    trash = f;

                                    break;

                                }

                            }

                            trees.add(folderTreeView);

                            folderTreeViewModel.initialize(account, new Command() {

                                @Override

                                public void execute() {

                                    createMySharedTree();

                                }

                            });

                            HorizontalPanel separator = new HorizontalPanel();

                            separator.addStyleName("pithos-statisticsSeparator");

                            separator.add(new HTML(""));

                            trees.add(separator);

                            groupTreeViewModel = new GroupTreeViewModel(Pithos.this);

                            groupTreeView = new GroupTreeView(groupTreeViewModel);

                            treeViews.add(groupTreeView);

                            trees.add(groupTreeView);

                            folderTreeView.showStatistics(account);

                        }

                    }

                });

            }

        });

    }

    public void scheduleResfresh() {

        Scheduler.get().scheduleFixedDelay(new RepeatingCommand() {

            @Override

            public boolean execute() {

                final Folder f = getSelection();

                if(f == null) {

                    return true;

                }

                HeadRequest<Folder> head = new HeadRequest<Folder>(Folder.class, getStorageAPIURL(), f.getOwnerID(), "/" + f.getContainer()) {

                    @Override

                    public void onSuccess(Folder _result) {

                        lastModified = new Date();

                        if(getSelectedTree().equals(folderTreeView)) {

                            updateFolder(f, true, new Command() {

                                @Override

                                public void execute() {

                                    scheduleResfresh();

                                }

                            }, false);

                        }

                        else if(getSelectedTree().equals(mysharedTreeView)) {

                            updateSharedFolder(f, true, new Command() {

                                @Override

                                public void execute() {

                                    scheduleResfresh();

                                }

                            });

                        }

                        else {

                            scheduleResfresh();

                        }

                    }

                    @Override

                    public void onError(Throwable t) {

                        if(t instanceof RestException && ((RestException) t).getHttpStatusCode() == HttpStatus.SC_NOT_MODIFIED) {

                            scheduleResfresh();

                        }

                        else if(retries >= MAX_RETRIES) {

                            LOG("Error heading folder. ", t);

                            setError(t);

                            if(t instanceof RestException) {

                                displayError("Error heading folder: " + ((RestException) t).getHttpStatusText());

                            }

                            else {

                                displayError("System error heading folder: " + t.getMessage());

                            }

                        }

                        else {//retry

                            LOG("Retry ", retries);

                            Scheduler.get().scheduleDeferred(this);

                        }

                    }

                    @Override

                    protected void onUnauthorized(Response response) {

                        if(retries >= MAX_RETRIES) {

                            sessionExpired();

                        }

                        else //retry

                        {

                            Scheduler.get().scheduleDeferred(this);

                        }

                    }

                };

                head.setHeader(Const.X_AUTH_TOKEN, getUserToken());

                head.setHeader(Const.IF_MODIFIED_SINCE, DateTimeFormat.getFormat(Const.DATE_FORMAT_1).format(lastModified, TimeZone.createTimeZone(0)) + " GMT");

                Scheduler.get().scheduleDeferred(head);

                return false;

            }

        }, 3000);

    }

    public void applyPermissions(Folder f) {

        if(f != null) {

            if(f.isInTrash()) {

                upload.setEnabled(false);

                disableUploadArea();

            }

            else {

                Boolean[] perms = f.getPermissions().get(userID);

                if(f.getOwnerID().equals(userID) || (perms != null && perms[1] != null && perms[1])) {

                    upload.setEnabled(true);

                    enableUploadArea();

                }

                else {

                    upload.setEnabled(false);

                    disableUploadArea();

                }

            }

        }

        else {

            upload.setEnabled(false);

            disableUploadArea();

        }

    }

    @SuppressWarnings({"rawtypes", "unchecked"})

    public void deselectOthers(TreeView _selectedTree, SingleSelectionModel model) {

        selectedTree = _selectedTree;

        for(SingleSelectionModel s : selectionModels) {

            if(!s.equals(model) && s.getSelectedObject() != null) {

                s.setSelected(s.getSelectedObject(), false);

            }

        }

    }

    public void showFiles(final Folder f) {

        Set<File> files = f.getFiles();

        showFiles(files);

    }

    public void showFiles(Set<File> files) {

        fileList.setFiles(new ArrayList<File>(files));

    }

    /**

     * Parse and store the user credentials to the appropriate fields.

     */

    private boolean parseUserCredentials() {

        final String cookie = otherProperties.get(Const.AUTH_COOKIE);

        String auth = Cookies.getCookie(cookie);

        if(auth == null) {

            authenticateUser();

            return false;

        }

        if(auth.startsWith("\"")) {

            auth = auth.substring(1);

        }

        if(auth.endsWith("\"")) {

            auth = auth.substring(0, auth.length() - 1);

        }

        String[] authSplit = auth.split("\\" + config.cookieSeparator(), 2);

        if(authSplit.length != 2) {

            authenticateUser();

            return false;

        }

        this.userID = authSplit[0];

        this.userToken = authSplit[1];

        String gotoUrl = Window.Location.getParameter("goto");

        if(gotoUrl != null && gotoUrl.length() > 0) {

            Window.Location.assign(gotoUrl);

            return false;

        }

        return true;

    }

    /**

     * Redirect the user to the login page for authentication.

     */

    protected void authenticateUser() {

        Dictionary otherProperties = Dictionary.getDictionary(Const.OTHER_PROPERTIES);

        Window.Location.assign(otherProperties.get(Const.LOGIN_URL) + Window.Location.getHref());

    }

    public void fetchAccount(final Command callback) {

        String path = "?format=json";

        GetRequest<AccountResource> getAccount = new GetRequest<AccountResource>(AccountResource.class, getStorageAPIURL(), userID, path) {

            @Override

            public void onSuccess(AccountResource accountResource) {

                account = accountResource;

                if(callback != null) {

                    callback.execute();

                }