Synnefo » Pithos

/*

 * Copyright 2007, 2008, 2009 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.rest.GetCommand;

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

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

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

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

import java.util.List;

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

import com.google.gwt.dom.client.NativeEvent;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

/**

 * A component that displays a list of the user's groups.

 */

public class Groups extends Composite implements SelectionHandler, OpenHandler {

        /**

         * An image bundle for this widget.

         */

        public interface Images extends Tree.Resources, ClientBundle, FileMenu.Images, EditMenu.Images, GroupMenu.Images, MessagePanel.Images {

                /**

                 * Will bundle the file 'groupevent.png' residing in the package

                 * 'gr.ebs.gss.resources'.

                 *

                 * @return the image prototype

                 */

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

                ImageResource groupImage();

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

                ImageResource delete();

        }

        /**

         * cached latest group selection (for selecting and expanding on refresh)

         */

        private String selectedGroup = null;

        /**

         * The tree widget that displays the groups.

         */

        private Tree tree;

        /**

         * A cached copy of the currently selected group widget.

         */

        private TreeItem current;

        /**

         * A cached copy of the previously selected group widget.

         */

        private TreeItem previous;

        /**

         * The widget's image bundle.

         */

        private final Images images;

        private GroupContextMenu menu;

        /**

         * Constructs a new groups widget with a bundle of images.

         *

         * @param newImages a bundle that provides the images for this widget

         */

        public Groups(final Images newImages) {

                images = newImages;

                menu = new GroupContextMenu(images);

                tree = new Tree(newImages);

                this.addHandler(new ContextMenuHandler() {

                        @Override

                        public void onContextMenu(ContextMenuEvent event) {

                                if(current==null) return;

                                int left = current.getAbsoluteLeft() + 40;

                                int top = current.getAbsoluteTop() + 20;

                                showPopup(left, top);

                        }

                }, ContextMenuEvent.getType());

                tree.addSelectionHandler(this);

                tree.addOpenHandler(this);

                tree.setAnimationEnabled(true);

                initWidget(tree);

                setStylePrimaryName("gss-Groups");

                sinkEvents(Event.ONCONTEXTMENU);

                sinkEvents(Event.ONMOUSEUP);

                sinkEvents(Event.ONDBLCLICK);

        }

        /**

         * Make an RPC call to retrieve the groups that belong to the specified

         * user.

         */

        public void updateGroups() {

                GetCommand<GroupsResource> gg = new GetCommand<GroupsResource>(GroupsResource.class, GSS.get().getCurrentUserResource().getGroupsPath(),null){

                        @Override

                        public void onComplete() {

                                GroupsResource res = getResult();

                                MultipleGetCommand<GroupResource> ga = new MultipleGetCommand<GroupResource>(GroupResource.class, res.getGroupPaths().toArray(new String[]{}), null){

                                        @Override

                                        public void onComplete() {

                                                List<GroupResource> groupList = getResult();

                                                tree.clear();

                                                for (int i = 0; i < groupList.size(); i++) {

                                                        final TreeItem item = new TreeItem();

                                                        item.setWidget(imageItemHTML(images.groupImage(), groupList.get(i).getName(),item));

                                                        item.setUserObject(groupList.get(i));

                                                        tree.addItem(item);

                                                        updateUsers(item);

                                                }

                                        }

                                        @Override

                                        public void onError(Throwable t) {

                                                GWT.log("", t);

                                        }

                                        @Override

                                        public void onError(String p, Throwable throwable) {

                                                GWT.log("Path:"+p, throwable);

                                        }

                                };

                                DeferredCommand.addCommand(ga);

                        }

                        @Override

                        public void onError(Throwable t) {

                        }

                };

                DeferredCommand.addCommand(gg);

        }

        /**

         *  update status panel with currently showing file stats

         */

        public void updateCurrentlyShowingStats() {

                GSS.get().getStatusPanel().updateCurrentlyShowing(null); //clear stats - nothing to show for the groups tab

        }

        /**

         * A helper method to simplify adding tree items that have attached images.

         * {@link #addImageItem(TreeItem, String) code}

         *

         * @param parent the tree item to which the new item will be added.

         * @param title the text associated with this item.

         * @param imageProto

         * @return the new tree item

         */

        private TreeItem addImageItem(final TreeItem parent, final String title, final ImageResource imageProto) {

                final TreeItem item = new TreeItem();

                item.setWidget(imageItemHTML(imageProto, title,item));

                parent.addItem(item);

                return item;

        }

        /**

         * Generates HTML for a tree item with an attached icon.

         *

         * @param imageProto the icon image

         * @param title the title of the item

         * @return the resultant HTML

         */

        private HTML imageItemHTML(final ImageResource imageProto, final String title,final TreeItem item) {

                final HTML link = new HTML("<a class='hidden-link' href='javascript:;'>" + "<span>" + AbstractImagePrototype.create(imageProto).getHTML() + "&nbsp;" + title + "</span>" + "</a>"){

                        @Override

                        public void onBrowserEvent(Event event) {

                                switch (DOM.eventGetType(event)) {

                                        case Event.ONMOUSEDOWN:

                                                if (DOM.eventGetButton(event) == NativeEvent.BUTTON_RIGHT || DOM.eventGetButton(event) == NativeEvent.BUTTON_LEFT)

                                                        onSelection(item);

                                                break;

                                }

                                super.onBrowserEvent(event);

                        }

                };

                link.sinkEvents(Event.ONMOUSEDOWN);

                return link;

        }

        protected void showPopup(final int x, final int y) {

                if (getCurrent() == null){

                        GWT.log("[POPUP IS NULL]", null);

                        return;

                }

                menu.hide();

                menu = new GroupContextMenu(images);

                menu.setPopupPosition(x, y);

                menu.show();

        }

        /**

         * Generate an RPC request to retrieve the users of the specified group for

         * display.

         *

         * @param userId the ID of the current user

         * @param groupItem the TreeItem widget that corresponds to the requested

         *            group

         */

        void updateUsers(final TreeItem groupItem) {

                if(groupItem.getUserObject() instanceof GroupResource){

                        GroupResource res = (GroupResource) groupItem.getUserObject();

                        MultipleGetCommand<GroupUserResource> gu = new MultipleGetCommand<GroupUserResource>(GroupUserResource.class, res.getUserPaths().toArray(new String[]{}), null){

                                @Override

                                public void onComplete() {

                                        List<GroupUserResource> users = getResult();

                                        groupItem.removeItems();

                                        for (int i = 0; i < users.size(); i++) {

                                                final TreeItem userItem = addImageItem(groupItem, users.get(i).getName() + " <" + users.get(i).getUsername() + ">", images.permUser());

                                                userItem.setUserObject(users.get(i));

                                        }

                                        if (selectedGroup != null && groupItem.getText().equals(selectedGroup)) {

                                                //SelectionEvent.fire(tree, groupItem);;

                                                onSelection(groupItem);

                                                groupItem.setState(true);

                                        }

                                }

                                @Override

                                public void onError(Throwable t) {

                                        GWT.log("", t);

                                }

                                @Override

                                public void onError(String p, Throwable throwable) {

                                        GWT.log("Path:"+p, throwable);

                                }

                        };

                        DeferredCommand.addCommand(gu);

                }

        }

        /**

         * Retrieve the current.

         *

         * @return the current

         */

        TreeItem getCurrent() {

                return current;

        }

        /**

         * Modify the current.

         *

         * @param newCurrent the current to set

         */

        void setCurrent(final TreeItem newCurrent) {

                current = newCurrent;

        }

        /**

         * Retrieve the previous.

         *

         * @return the previous

         */

        private TreeItem getPrevious() {

                return previous;

        }

        /**

         * Modify the previous.

         *

         * @param newPrevious the previous to set

         */

        private void setPrevious(final TreeItem newPrevious) {

                previous = newPrevious;

        }

        @Override

        public void setVisible(final boolean visible) {

                super.setVisible(visible);

                if (visible)

                        updateGroups();

        }

        @Override

        public void onSelection(SelectionEvent event) {

                final TreeItem item = (TreeItem)event.getSelectedItem();

                onSelection(item);

        }

        private void onSelection(TreeItem item){

                final Object selected = item.getUserObject();

                // Preserve the previously selected item, so that the current's

                // onClick() method gets a chance to find it.

                if (getPrevious() != null)

                        getPrevious().getWidget().removeStyleName("gss-SelectedRow");

                setCurrent(item);

                getCurrent().getWidget().addStyleName("gss-SelectedRow");

                setPrevious(getCurrent());

                GSS.get().setCurrentSelection(selected);

                //cache the latest top level node (group) for selecting and expanding on refresh

                if (item.getParentItem() == null)

                        selectedGroup = item.getText();

                else

                        selectedGroup = item.getParentItem().getText();

        }

        @Override

        public void onOpen(OpenEvent event) {

                final TreeItem item = (TreeItem) event.getTarget();

                updateUsers(item);

        }

}