/**
    * This file Copyright (c) 2015-2018 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.ui.contentapp.renderer;
  
  import info.magnolia.event.EventBus;
  import info.magnolia.ui.api.action.ActionDefinition;
  import info.magnolia.ui.api.availability.AvailabilityChecker;
  import info.magnolia.ui.api.availability.AvailabilityDefinition;
  import info.magnolia.ui.api.event.ChooseDialogEventBus;
  import info.magnolia.ui.api.view.View;
  import info.magnolia.ui.dialog.actionarea.ActionListener;
  import info.magnolia.ui.dialog.actionarea.renderer.DefaultEditorActionRenderer;
  import info.magnolia.ui.framework.overlay.ViewAdapter;
  import info.magnolia.ui.workbench.event.SelectionChangedEvent;
  
  import java.util.Collections;
  import java.util.Set;
  
  import javax.inject.Inject;
  import javax.inject.Named;
  
  import com.google.common.collect.Lists;
  import com.vaadin.ui.Component;
  
  /**
   * {@link info.magnolia.ui.dialog.actionarea.renderer.ActionRenderer} implementation that alters the 'enabled'-state of
   * the underlying Vaadin view based on {@link AvailabilityChecker} decision made against a current selection provided
   * by {@link SelectionChangedEvent} via {@link ChooseDialogEventBus}.
   */
  public class SelectionSensitiveActionRenderer extends DefaultEditorActionRenderer {
  
      private final EventBus chooseDialogEventBus;
      private final AvailabilityChecker availabilityChecker;
  
      @Inject
      public SelectionSensitiveActionRenderer(@Named(ChooseDialogEventBus.NAME) EventBus chooseDialogEventBus, AvailabilityChecker availabilityChecker) {
          this.chooseDialogEventBus = chooseDialogEventBus;
          this.availabilityChecker = availabilityChecker;
      }
  
      @Override
      public View start(final ActionDefinition definition, ActionListener listener) {
          View view = super.start(definition, listener);
          final Component button = view.asVaadinComponent();
          chooseDialogEventBus.addHandler(SelectionChangedEvent.class, new SelectionChangedEvent.Handler() {
  
              @Override
              public void onSelectionChanged(SelectionChangedEvent event) {
                  Set<Object> itemIds = event.getItemIds();
                  if (itemIds == null || itemIds.isEmpty()) {
                      itemIds = Collections.emptySet();
                  }
  
                  AvailabilityDefinition availability = definition.getAvailability();
                  button.setEnabled(availabilityChecker.isAvailable(availability, Lists.newLinkedList(itemIds)));
              }
          });
          return new ViewAdapter(button);
      }
  
  }