Synnefo » Pithos

/*

 * Copyright (c) 2011 Greek Research and Technology Network

 */

package gr.grnet.pithos.web.client.foldertree;

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

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

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

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

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

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

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

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

import gr.grnet.pithos.web.client.GSS;

import gr.grnet.pithos.web.client.foldertree.FolderTreeView.FolderCell;

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

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

import java.util.Iterator;

import java.util.Set;

public class FolderTreeViewModel implements TreeViewModel {

    private SingleSelectionModel<Folder> selectionModel = new SingleSelectionModel<Folder>();

    private ListDataProvider<Folder> rootDataProvider = new ListDataProvider<Folder>();

    public FolderTreeViewModel() {

        Handler selectionHandler = new SelectionChangeEvent.Handler() {

            @Override

            public void onSelectionChange(SelectionChangeEvent event) {

                NodeInfo<Folder> nodeInfo = (NodeInfo<Folder>) getNodeInfo(selectionModel.getSelectedObject());

                if(nodeInfo == null || nodeInfo.getValueUpdater() == null) {

//                    GSS.get().showFileList(selectionModel.getSelectedObject());

                }

                else

                    nodeInfo.getValueUpdater().update(selectionModel.getSelectedObject());

                GSS.get().setCurrentSelection(selectionModel.getSelectedObject());

            }

        };

        selectionModel.addSelectionChangeHandler(selectionHandler);

    }

    @Override

    public <T> NodeInfo<?> getNodeInfo(T value) {

        if (value == null) {

            Folder f = new Folder("Loading ...");

            rootDataProvider.getList().add(f);

            return new DefaultNodeInfo<Folder>(rootDataProvider, new FolderCell(), selectionModel, null);

        }

        else {

            final Folder f = (Folder) value;

            final ListDataProvider<Folder> dataProvider = new ListDataProvider<Folder>();

            dataProvider.flush();

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

                @Override

                public void execute() {

                    final GSS app = GSS.get();

                    String path = app.getApiPath() + app.getUsername() + "/" + f.getContainer() + "?format=json&delimiter=/&prefix=" + f.getPrefix();

                    GetRequest<Folder> getFolder = new GetRequest<Folder>(Folder.class, path, f) {

                        @Override

                        public void onSuccess(Folder result) {

                            Iterator<Folder> iter = result.getSubfolders().iterator();

                            fetchFolder(iter, dataProvider, result.getSubfolders());

                        }

                        @Override

                        public void onError(Throwable t) {

                            GWT.log("Error getting folder", t);

                            if (t instanceof RestException)

                                GSS.get().displayError("Error getting folder: " + ((RestException) t).getHttpStatusText());

                            else

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

                        }

                    };

                    Scheduler.get().scheduleDeferred(getFolder);

                }

            });

            return new DefaultNodeInfo<Folder>(dataProvider, new FolderCell(), selectionModel, null);

        }

    }

    @Override

    public boolean isLeaf(Object o) {

        if (o instanceof Folder) {

            Folder f = (Folder) o;

            return f.getSubfolders().isEmpty();

        }

        return false;

    }

    private void fetchFolder(final Iterator<Folder> iter, final ListDataProvider<Folder> dataProvider, final Set<Folder> folders) {

        if (iter.hasNext()) {

            final Folder f = iter.next();

            GSS app = GSS.get();

            String path = app.getApiPath() + app.getUsername() + "/" + f.getContainer() + "?format=json&delimiter=/&prefix=" + f.getPrefix();

            GetRequest<Folder> getFolder = new GetRequest<Folder>(Folder.class, path, f) {

                @Override

                public void onSuccess(Folder result) {

                    fetchFolder(iter, dataProvider, folders);

                }

                @Override

                public void onError(Throwable t) {

                    GWT.log("Error getting folder", t);

                    if (t instanceof RestException)

                        GSS.get().displayError("Error getting folder: " + ((RestException) t).getHttpStatusText());

                    else

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

                }

            };

            Scheduler.get().scheduleDeferred(getFolder);

        }

        else {

            dataProvider.getList().clear();

            dataProvider.getList().addAll(folders);

        }

    }

    public void initialize(AccountResource account) {

        Iterator<Folder> iter = account.getContainers().iterator();

        fetchFolder(iter, rootDataProvider, account.getContainers());

    }

}