ExecuteCommandButtonItemsProvider.java

/*******************************************************************************
 * Copyright (c) 2012-2017 Codenvy, S.A.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Codenvy, S.A. - initial API and implementation
 *******************************************************************************/
package org.eclipse.che.ide.command.toolbar.commands.button;

import org.eclipse.che.ide.api.app.AppContext;
import org.eclipse.che.ide.api.command.CommandGoal;
import org.eclipse.che.ide.api.command.CommandImpl;
import org.eclipse.che.ide.api.machine.MachineEntity;
import org.eclipse.che.ide.ui.menubutton.ItemsProvider;
import org.eclipse.che.ide.ui.menubutton.MenuItem;
import org.eclipse.che.ide.util.Pair;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Optional;
import java.util.Set;

import static java.util.Optional.ofNullable;
import static java.util.stream.Collectors.toList;

/** Provides items for {@link ExecuteCommandButton}. */
public class ExecuteCommandButtonItemsProvider implements ItemsProvider {

    private final AppContext       appContext;
    private final MenuItemsFactory menuItemsFactory;
    private final CommandGoal      goal;
    private final Set<CommandImpl> commands;

    private DataChangedHandler dataChangedHandler;
    private MenuItem           defaultItem;

    ExecuteCommandButtonItemsProvider(AppContext appContext, MenuItemsFactory menuItemsFactory, CommandGoal goal) {
        this.appContext = appContext;
        this.menuItemsFactory = menuItemsFactory;
        this.goal = goal;
        this.commands = new HashSet<>();
    }

    @Override
    public Optional<MenuItem> getDefaultItem() {
        return ofNullable(defaultItem);
    }

    void setDefaultItem(MenuItem item) {
        defaultItem = item;
    }

    @Override
    public List<MenuItem> getItems() {
        final List<MenuItem> items = new ArrayList<>(commands.size());

        if (defaultItem != null && defaultItem instanceof MachineItem) {
            items.add(menuItemsFactory.newMachineItem((MachineItem)defaultItem));
        }

        for (CommandImpl command : commands) {
            items.add(menuItemsFactory.newCommandItem(command));
        }

        if (items.isEmpty()) {
            items.add(menuItemsFactory.newGuideItem(goal));
        }

        return items;
    }

    @Override
    public boolean isGroup(MenuItem item) {
        if (item instanceof CommandItem) {
            return appContext.getActiveRuntime().getMachines().size() > 1;
        }

        return false;
    }

    @Override
    public Pair<List<MenuItem>, String> getChildren(MenuItem parent) {
        List<MenuItem> items = new ArrayList<>();

        if (parent instanceof CommandItem) {
            CommandImpl command = ((CommandItem)parent).getCommand();
            List<MachineEntity> machines = appContext.getActiveRuntime().getMachines();

            items.addAll(machines.stream()
                                 .map(machine -> menuItemsFactory.newMachineItem(command, machine))
                                 .collect(toList()));
        }

        return Pair.of(items, null);
    }

    @Override
    public void setDataChangedHandler(DataChangedHandler handler) {
        dataChangedHandler = handler;
    }

    /** Adds the given {@code command} to the provider. */
    public void addCommand(CommandImpl command) {
        commands.add(command);

        if (dataChangedHandler != null) {
            dataChangedHandler.onDataChanged();
        }
    }

    /** Removes the given {@code command} from the provider. */
    public void removeCommand(CommandImpl command) {
        commands.remove(command);

        // reset the defaultItem
        if (defaultItem instanceof CommandItem) {
            final CommandImpl cmd = ((CommandItem)defaultItem).getCommand();
            if (cmd.equals(command)) {
                defaultItem = null;
            }
        }

        if (dataChangedHandler != null) {
            dataChangedHandler.onDataChanged();
        }
    }

    /** Checks whether the {@link GuideItem} is the only item which provider contains. */
    boolean containsGuideItemOnly() {
        List<MenuItem> items = getItems();

        return items.isEmpty() || (items.size() == 1 && items.get(0) instanceof GuideItem);
    }
}