Synnefo » Pithos

/*

 * Copyright 2007, 2008, 2009, 2010 Electronic Business Systems Ltd.

 *

 * This file is part of GSS.

 *

 * GSS is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * GSS is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with GSS.  If not, see <http://www.gnu.org/licenses/>.

 */

package gr.ebs.gss.client;

import gr.ebs.gss.client.clipboard.Clipboard;

import gr.ebs.gss.client.dnd.DnDFocusPanel;

import gr.ebs.gss.client.dnd.DnDSimpleFocusPanel;

import gr.ebs.gss.client.rest.GetCommand;

import gr.ebs.gss.client.rest.RestException;

import gr.ebs.gss.client.rest.resource.FileResource;

import gr.ebs.gss.client.rest.resource.FolderResource;

import gr.ebs.gss.client.rest.resource.TrashResource;

import gr.ebs.gss.client.rest.resource.UserResource;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import com.allen_sauer.gwt.dnd.client.DragContext;

import com.allen_sauer.gwt.dnd.client.PickupDragController;

import com.allen_sauer.gwt.dnd.client.VetoDragException;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

/**

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

 */

public class GSS implements EntryPoint, ResizeHandler {

        /**

         * A constant that denotes the completion of an IncrementalCommand.

         */

        public static final boolean DONE = false;

        public static final int VISIBLE_FILE_COUNT = 100;

        /**

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

         * programmatic access to all the images needed by widgets.

         */

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

        private GlassPanel glassPanel = new GlassPanel();

        /**

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

         * application into a single bundle.

         */

        public interface Images extends ClientBundle, TopPanel.Images, StatusPanel.Images, FileMenu.Images, EditMenu.Images, SettingsMenu.Images, GroupMenu.Images, FilePropertiesDialog.Images, MessagePanel.Images, FileList.Images, SearchResults.Images, Search.Images, Groups.Images, Folders.Images {

                @Source("gr/ebs/gss/resources/document.png")

                ImageResource folders();

                @Source("gr/ebs/gss/resources/edit_group_22.png")

                ImageResource groups();

                @Source("gr/ebs/gss/resources/search.png")

                ImageResource search();

        }

        /**

         * The single GSS instance.

         */

        private static GSS singleton;

        /**

         * Gets the singleton GSS instance.

         *

         * @return the GSS object

         */

        public static GSS get() {

                if (GSS.singleton == null)

                        GSS.singleton = new GSS();

                return GSS.singleton;

        }

        /**

         * The Application Clipboard implementation;

         */

        private Clipboard clipboard = new Clipboard();

        private UserResource currentUserResource;

        /**

         * The top panel that contains the menu bar.

         */

        private TopPanel topPanel;

        /**

         * The panel that contains the various system messages.

         */

        private MessagePanel messagePanel = new MessagePanel(GSS.images);

        /**

         * The bottom panel that contains the status bar.

         */

        private StatusPanel statusPanel = new StatusPanel(GSS.images);

        /**

         * The top right panel that displays the logged in user details

         */

        private UserDetailsPanel userDetailsPanel = new UserDetailsPanel();

        /**

         * The file list widget.

         */

        private FileList fileList;

        /**

         * The group list widget.

         */

        private Groups groups = new Groups(images);

        /**

         * The search result widget.

         */

        private SearchResults searchResults;

        /**

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

         */

        private TabPanel inner = new DecoratedTabPanel();

        /**

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

         */

        private HorizontalSplitPanel splitPanel = new HorizontalSplitPanel();

        /**

         * The horizontal panel that will contain the search and status panels.

         */

        private DockPanel searchStatus = new DockPanel();

        /**

         * The search widget.

         */

        private Search search;

        /**

         * The widget that displays the tree of folders.

         */

        private Folders folders = new Folders(images);

        /**

         * 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;

        /**

         * The authentication token of the current user.

         */

        private String token;

        /**

         * A map that stores a set of String URI and the corresponding object

         * in order history functionality to be implemented.

         */

        private Map<String, Object> map = new HashMap<String, Object>();

        /**

         * The WebDAV password of the current user

         */

        private String webDAVPassword;

        private PickupDragController dragController;

        public void onModuleLoad() {

                // Initialize the singleton before calling the constructors of the

                // various widgets that might call GSS.get().

                singleton = this;

                RootPanel.get().add(glassPanel, 0, 0);

                parseUserCredentials();

                dragController = new PickupDragController(RootPanel.get(), false) {

                        @Override

                        public void previewDragStart() throws VetoDragException {

                                super.previewDragStart();

                                if (context.selectedWidgets.isEmpty())

                                        throw new VetoDragException();

                                if (context.draggable != null)

                                        if (context.draggable instanceof DnDFocusPanel) {

                                                DnDFocusPanel toDrop = (DnDFocusPanel) context.draggable;

                                                // prevent drag and drop for trashed files and for

                                                // unselected tree items

                                                if (toDrop.getFiles() != null && folders.isTrashItem(folders.getCurrent()))

                                                        throw new VetoDragException();

                                                else if (toDrop.getItem() != null && !toDrop.getItem().equals(folders.getCurrent()))

                                                        throw new VetoDragException();

                                                else if (toDrop.getItem() != null && !toDrop.getItem().isDraggable())

                                                        throw new VetoDragException();

                                        } else if (context.draggable instanceof DnDSimpleFocusPanel) {

                                                DnDSimpleFocusPanel toDrop = (DnDSimpleFocusPanel) context.draggable;

                                                // prevent drag and drop for trashed files and for

                                                // unselected tree items

                                                if (toDrop.getFiles() != null && folders.isTrashItem(folders.getCurrent()))

                                                        throw new VetoDragException();

                                        }

                        }

                        @Override

                        protected Widget newDragProxy(DragContext aContext) {

                                AbsolutePanel container = new AbsolutePanel();

                                DOM.setStyleAttribute(container.getElement(), "overflow", "visible");

                                for (Iterator iterator = aContext.selectedWidgets.iterator(); iterator.hasNext();) {

                                        HTML html = null;

                                        Widget widget = (Widget) iterator.next();

                                        if (widget instanceof DnDFocusPanel) {

                                                DnDFocusPanel book = (DnDFocusPanel) widget;

                                                html = book.cloneHTML();

                                        } else if (widget instanceof DnDSimpleFocusPanel) {

                                                DnDSimpleFocusPanel book = (DnDSimpleFocusPanel) widget;

                                                html = book.cloneHTML();

                                        }

                                        if (html == null)

                                                container.add(new Label("Drag ME"));

                                        else

                                                container.add(html);

                                }

                                return container;

                        }

                };

                dragController.setBehaviorDragProxy(true);

                dragController.setBehaviorMultipleSelection(false);

                topPanel = new TopPanel(GSS.images);

                topPanel.setWidth("100%");

                messagePanel.setWidth("100%");

                messagePanel.setVisible(false);

                search = new Search(images);

                searchStatus.add(search, DockPanel.WEST);

                searchStatus.add(userDetailsPanel, DockPanel.EAST);

                searchStatus.setCellHorizontalAlignment(userDetailsPanel, HasHorizontalAlignment.ALIGN_RIGHT);

                searchStatus.setCellVerticalAlignment(search, HasVerticalAlignment.ALIGN_MIDDLE);

                searchStatus.setCellVerticalAlignment(userDetailsPanel, HasVerticalAlignment.ALIGN_MIDDLE);

                searchStatus.setWidth("100%");

                fileList = new FileList(images);

                searchResults = new SearchResults(images);

                // Inner contains the various lists.

                inner.setAnimationEnabled(true);

                inner.getTabBar().addStyleName("gss-MainTabBar");

                inner.getDeckPanel().addStyleName("gss-MainTabPanelBottom");

                inner.add(fileList, createHeaderHTML(AbstractImagePrototype.create(images.folders()), "Files"), true);

                inner.add(groups, createHeaderHTML(AbstractImagePrototype.create(images.groups()), "Groups"), true);

                inner.add(searchResults, createHeaderHTML(AbstractImagePrototype.create(images.search()), "Search Results"), true);

                inner.setWidth("100%");

                inner.selectTab(0);

                inner.addSelectionHandler(new SelectionHandler<Integer>() {

                        @Override

                        public void onSelection(SelectionEvent<Integer> event) {

                                int tabIndex = event.getSelectedItem();

                                TreeItem treeItem = GSS.get().getFolders().getCurrent();

                                switch (tabIndex) {

                                        case 0:

//                                                Files tab selected

                                                fileList.clearSelectedRows();

                                                fileList.updateCurrentlyShowingStats();

                                                break;

                                        case 1:

//                                                Groups tab selected

                                                groups.updateCurrentlyShowingStats();

                                        updateHistory("Groups", treeItem);

                                                break;

                                        case 2:

//                                                Search tab selected

                                                searchResults.clearSelectedRows();

                                                searchResults.updateCurrentlyShowingStats();

                                        updateHistory("Search", treeItem);

                                                break;

                                }

                        }

                });

//                If the application starts with no history token, redirect to a new "Files" state

                String initToken = History.getToken();

                if(initToken.length() == 0)

                        History.newItem("Files");

//                   Add history listener to handle any history events

                   History.addValueChangeHandler(new ValueChangeHandler<String>() {

                              public void onValueChange(ValueChangeEvent<String> event) {

                                String historyToken = event.getValue();

                                try {

                                        if(historyToken.equals("Search"))

                                                inner.selectTab(2);

                                        else if(historyToken.equals("Groups"))

                                                inner.selectTab(1);

                                        else if(historyToken.equals("Files")|| historyToken.length()==0)

                                                inner.selectTab(0);

                                                else

                                                        SelectionEvent.fire(GSS.get().getFolders().getPopupTree(), (TreeItem) getHistoryItem(historyToken));

                                        } catch (IndexOutOfBoundsException e) {

                                                inner.selectTab(0);

                                                }

                                        }

                              });

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

                splitPanel.setLeftWidget(folders);

                splitPanel.setRightWidget(inner);

                splitPanel.setSplitPosition("25%");

                splitPanel.setSize("100%", "100%");

                splitPanel.addStyleName("gss-splitPanel");

                // Create a dock panel that will contain the menu bar at the top,

                // the shortcuts to the left, the status bar at the bottom and the

                // right panel taking the rest.

                VerticalPanel outer = new VerticalPanel();

                outer.add(topPanel);

                outer.add(searchStatus);

                outer.add(messagePanel);

                outer.add(splitPanel);

                outer.add(statusPanel);

                outer.setWidth("100%");

                outer.setCellHorizontalAlignment(messagePanel, HasHorizontalAlignment.ALIGN_CENTER);

                outer.setSpacing(4);

                // 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.

                DeferredCommand.addCommand(new Command() {

                        public void execute() {

                                onWindowResized(Window.getClientHeight());

                        }

                });

        }

        /**

         * Fetches the User object for the specified username.

         *

         * @param username the username of the user

         */

        private void fetchUser(final String username) {

                String path = getApiPath() + username + "/";

                GetCommand<UserResource> getUserCommand = new GetCommand<UserResource>(UserResource.class, username, path, null) {

                        @Override

                        public void onComplete() {

                                currentUserResource = getResult();

                                final String announcement = currentUserResource.getAnnouncement();

                                if (announcement != null)

                                        DeferredCommand.addCommand(new Command() {

                                                public void execute() {

                                                        displayInformation(announcement);

                                                }

                                        });

                        }

                        @Override

                        public void onError(Throwable t) {

                                GWT.log("Fetching user error", t);

                                if (t instanceof RestException)

                                        GSS.get().displayError("No user found:" + ((RestException) t).getHttpStatusText());

                                else

                                        GSS.get().displayError("System error fetching user data:" + t.getMessage());

                                authenticateUser();

                        }

                };

                DeferredCommand.addCommand(getUserCommand);

        }

        /**

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

         */

        private void parseUserCredentials() {

                Configuration conf = (Configuration) GWT.create(Configuration.class);

                String cookie = conf.authCookie();

                String auth = Cookies.getCookie(cookie);

                if (auth == null) {

                        authenticateUser();

                        // Redundant, but silences warnings about possible auth NPE, below.

                        return;

                }

                int sepIndex = auth.indexOf(conf.cookieSeparator());

                if (sepIndex == -1)

                        authenticateUser();

                token = auth.substring(sepIndex + 1);

                final String username = auth.substring(0, sepIndex);

                if (username == null)

                        authenticateUser();

                refreshWebDAVPassword();

                DeferredCommand.addCommand(new Command() {

                        public void execute() {

                                fetchUser(username);

                        }

                });

        }

        /**

         * Redirect the user to the login page for authentication.

         */

        protected void authenticateUser() {

                Configuration conf = (Configuration) GWT.create(Configuration.class);

                Window.Location.assign(conf.loginUrl() + "?next=" + GWT.getModuleBaseURL());

        }

        /**

         * Clear the cookie and redirect the user to the logout page.

         */

        void logout() {

                Configuration conf = (Configuration) GWT.create(Configuration.class);

                String cookie = conf.authCookie();

                String domain = Window.Location.getHostName();

                String path = Window.Location.getPath();

                Cookies.setCookie(cookie, "", null, domain, path, false);

                Window.Location.assign(conf.logoutUrl());

        }

        /**

         * Creates an HTML fragment that places an image & caption together, for use

         * in a group header.

         *

         * @param imageProto an image prototype for an image

         * @param caption the group caption

         * @return the header HTML fragment

         */

        private String createHeaderHTML(AbstractImagePrototype imageProto, String caption) {

                String captionHTML = "<table class='caption' cellpadding='0' " + "cellspacing='0'>" + "<tr><td class='lcaption'>" + imageProto.getHTML() + "</td><td class='rcaption'><b style='white-space:nowrap'>&nbsp;" + caption + "</b></td></tr></table>";

                return captionHTML;

        }

        private void onWindowResized(int height) {

                // Adjust the split panel to take up the available room in the window.

                int newHeight = height - splitPanel.getAbsoluteTop() - 44;

                if (newHeight < 1)

                        newHeight = 1;

                splitPanel.setHeight("" + newHeight);

        }

        @Override

        public void onResize(ResizeEvent event) {

                int height = event.getHeight();

                onWindowResized(height);

        }

        public boolean isFileListShowing() {

                int tab = inner.getTabBar().getSelectedTab();

                if (tab == 0)

                        return true;

                return false;

        }

        public boolean isSearchResultsShowing() {

                int tab = inner.getTabBar().getSelectedTab();

                if (tab == 2)

                        return true;

                return false;

        }

        /**

         * Make the user list visible.

         */

        public void showUserList() {

                inner.selectTab(1);

        }

        /**

         * Make the file list visible.

         */

        public void showFileList() {

                fileList.updateFileCache(false, true /*clear selection*/);

                inner.selectTab(0);

        }

        /**

         * Make the file list visible.

         *

         * @param update

         */

        public void showFileList(boolean update) {

                TreeItem currentFolder = getFolders().getCurrent();

                if (currentFolder != null) {

                        List<FileResource> files = null;

                        Object cachedObject = currentFolder.getUserObject();

                        if (cachedObject instanceof FolderResource) {

                                FolderResource folder = (FolderResource) cachedObject;

                                files = folder.getFiles();

                        } else if (cachedObject instanceof TrashResource) {

                                TrashResource folder = (TrashResource) cachedObject;

                                files = folder.getFiles();

                        }

                        if (files != null)

                                getFileList().setFiles(files);

                }

                fileList.updateFileCache(update, true /*clear selection*/);

                inner.selectTab(0);

        }

        /**

         * Make the search results visible.

         *

         * @param query the search query string

         */

        public void showSearchResults(String query) {

                searchResults.updateFileCache(query);

                searchResults.updateCurrentlyShowingStats();

                inner.selectTab(2);

        }

        /**

         * Display the 'loading' indicator.

         */

        public void showLoadingIndicator() {

                topPanel.getLoading().setVisible(true);

        }

        /**

         * Hide the 'loading' indicator.

         */

        public void hideLoadingIndicator() {

                topPanel.getLoading().setVisible(false);

        }

        /**

         * A native JavaScript method to reach out to the browser's window and

         * invoke its resizeTo() method.

         *

         * @param x the new width

         * @param y the new height

         */

        public static native void resizeTo(int x, int y) /*-{

                $wnd.resizeTo(x,y);

        }-*/;

        /**

         * A helper method that returns true if the user's list is currently visible

         * and false if it is hidden.

         *

         * @return true if the user list is visible

         */

        public boolean isUserListVisible() {

                return inner.getTabBar().getSelectedTab() == 1;

        }

        /**

         * Display an error message.

         *

         * @param msg the message to display

         */

        public void displayError(String msg) {

                messagePanel.displayError(msg);

        }

        /**

         * Display a warning message.

         *

         * @param msg the message to display

         */

        public void displayWarning(String msg) {

                messagePanel.displayWarning(msg);

        }

        /**

         * Display an informational message.

         *

         * @param msg the message to display

         */

        public void displayInformation(String msg) {

                messagePanel.displayInformation(msg);

        }

        /**

         * Retrieve the folders.

         *

         * @return the folders

         */

        public Folders getFolders() {

                return folders;

        }

        /**

         * Retrieve the search.

         *

         * @return the search

         */

        Search getSearch() {

                return search;

        }

        /**

         * Retrieve the currentSelection.

         *

         * @return the currentSelection

         */

        public Object getCurrentSelection() {

                return currentSelection;

        }

        /**

         * Modify the currentSelection.

         *

         * @param newCurrentSelection the currentSelection to set

         */

        public void setCurrentSelection(Object newCurrentSelection) {

                currentSelection = newCurrentSelection;

        }

        /**

         * Retrieve the groups.

         *

         * @return the groups

         */

        public Groups getGroups() {

                return groups;

        }

        /**

         * Retrieve the fileList.

         *

         * @return the fileList

         */

        public FileList getFileList() {

                return fileList;

        }

        public SearchResults getSearchResults() {

                return searchResults;

        }

        /**

         * Retrieve the topPanel.

         *

         * @return the topPanel

         */

        TopPanel getTopPanel() {

                return topPanel;

        }

        /**

         * Retrieve the clipboard.

         *

         * @return the clipboard

         */

        public Clipboard getClipboard() {

                return clipboard;

        }

        public StatusPanel getStatusPanel() {

                return statusPanel;

        }

        /**

         * Retrieve the userDetailsPanel.

         *

         * @return the userDetailsPanel

         */

        public UserDetailsPanel getUserDetailsPanel() {

                return userDetailsPanel;

        }

        /**

         * Retrieve the dragController.

         *

         * @return the dragController

         */

        public PickupDragController getDragController() {

                return dragController;

        }

        public String getToken() {

                return token;

        }

        public String getWebDAVPassword() {

                return webDAVPassword;

        }

        public void removeGlassPanel() {

                glassPanel.removeFromParent();

        }

        /**

         * Retrieve the currentUserResource.

         *

         * @return the currentUserResource

         */

        public UserResource getCurrentUserResource() {

                return currentUserResource;

        }

        /**

         * Modify the currentUserResource.

         *

         * @param newUser the new currentUserResource

         */

        public void setCurrentUserResource(UserResource newUser) {

                currentUserResource = newUser;

        }

        public static native void preventIESelection() /*-{

                $doc.body.onselectstart = function () { return false; };

        }-*/;

        public static native void enableIESelection() /*-{

                if ($doc.body.onselectstart != null)

                $doc.body.onselectstart = null;

        }-*/;

        /**

         * @return the absolute path of the API root URL

         */

        public String getApiPath() {

                Configuration conf = (Configuration) GWT.create(Configuration.class);

                return GWT.getModuleBaseURL() + conf.apiPath();

        }

        public void refreshWebDAVPassword() {

                Configuration conf = (Configuration) GWT.create(Configuration.class);

                String domain = Window.Location.getHostName();

                String path = Window.Location.getPath();

                String cookie = conf.webdavCookie();

                webDAVPassword = Cookies.getCookie(cookie);

                Cookies.setCookie(cookie, "", null, domain, path, false);

        }

        /**

         * @param key

         * @return Object of the corresponding String URI which is stored in the history map

         */

        public Object getHistoryItem(String key){

                return map.get(key);

        }

        /**

         * Replaces any whitespace in the given string to "+"

         * Sets a pair of key - object in the History (using a map)

         * and adds a new browser history entry

         * @param key

         * @param obj

         */

        public void updateHistory(String key, Object obj){

//                Replace any whitespace of the initial string to "+"

                String result = key.replaceAll("\\s","+");

//                Add a new pair key - object in the History map.

                map.put(result, obj);

//                Add a new browser history entry.

                History.newItem(result);

        }

}