/**
    * This file Copyright (c) 2012-2015 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.pages.app.editor;
  
  import info.magnolia.event.EventBus;
  import info.magnolia.i18nsystem.SimpleTranslator;
  import info.magnolia.pages.app.editor.event.ComponentMoveEvent;
  import info.magnolia.pages.app.editor.event.NodeSelectedEvent;
  import info.magnolia.ui.api.action.ActionExecutionException;
  import info.magnolia.ui.api.action.ActionExecutor;
  import info.magnolia.ui.api.app.SubAppContext;
  import info.magnolia.ui.api.app.SubAppEventBus;
  import info.magnolia.ui.api.event.ContentChangedEvent;
  import info.magnolia.ui.api.message.Message;
  import info.magnolia.ui.api.message.MessageType;
  import info.magnolia.ui.vaadin.editor.PageEditorListener;
  import info.magnolia.ui.vaadin.editor.PageEditorView;
  import info.magnolia.ui.vaadin.gwt.client.shared.AbstractElement;
  import info.magnolia.ui.vaadin.gwt.client.shared.PageEditorParameters;
  
  import javax.inject.Inject;
  import javax.inject.Named;
  import javax.inject.Singleton;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Presenter for the server side {@link PageEditorView}.
   * Serves multiple methods for actions triggered from the page editor.
   */
  @Singleton
  public class PageEditorPresenter implements PageEditorListener {
  
      private static final Logger log = LoggerFactory.getLogger(PageEditorPresenter.class);
  
      private final ActionExecutor actionExecutor;
      private final PageEditorView view;
      private final EventBus subAppEventBus;
      private final SubAppContext subAppContext;
      private final SimpleTranslator i18n;
  
      private AbstractElement selectedElement;
      private boolean moving = false;
      private Listener listener;
  
      @Inject
      public PageEditorPresenter(final ActionExecutor actionExecutor, PageEditorView view, final @Named(SubAppEventBus.NAME) EventBus subAppEventBus,
              SubAppContext subAppContext, SimpleTranslator i18n) {
          this.actionExecutor = actionExecutor;
          this.view = view;
          this.subAppEventBus = subAppEventBus;
          this.subAppContext = subAppContext;
          this.i18n = i18n;
          registerHandlers();
      }
  
      public PageEditorView start() {
          view.setListener(this);
          return view;
      }
  
      private void registerHandlers() {
          subAppEventBus.addHandler(ContentChangedEvent.class, new ContentChangedEvent.Handler() {
  
              @Override
              public void onContentChanged(ContentChangedEvent event) {
                  view.refresh();
             }
         });
         subAppEventBus.addHandler(ComponentMoveEvent.class, new ComponentMoveEvent.Handler() {
             @Override
             public void onMove(ComponentMoveEvent event) {
                 moving = event.isStart();
                 if (moving) {
                     view.startMoveComponent();
                 } else if (event.isServerSide()) {
                     view.cancelMoveComponent();
                 }
 
                 listener.onMove();
             }
         });
 
     }
 
     @Override
     public void onElementSelect(AbstractElement selectedElement) {
         this.selectedElement = selectedElement;
         subAppEventBus.fireEvent(new NodeSelectedEvent(selectedElement));
     }
 
     @Override
     public void onAction(String actionName, Object... args) {
         try {
             actionExecutor.execute(actionName, args);
         } catch (ActionExecutionException e) {
             Message error = new Message(MessageType.ERROR, i18n.translate("pages.pageEditorPresenter.actionExecutionError.message"), e.getMessage());
             log.error("An error occurred while executing action [{}]", actionName, e);
             subAppContext.getAppContext().sendLocalMessage(error);
         }
     }
 
     public AbstractElement getSelectedElement() {
         return selectedElement;
     }
 
     public void loadPageEditor(PageEditorParameters parameters) {
         view.load(parameters);
     }
 
     public void updateParameters(PageEditorParameters parameters) {
         view.update(parameters);
     }
 
     public boolean isMoving() {
         return moving;
     }
 
     public void setListener(Listener listener) {
         this.listener = listener;
     }
 
     /**
      * Listener interface to call {@link PageEditorPresenter}.
      */
     interface Listener {
         void onMove();
     }
 }