/**
    * This file Copyright (c) 2010-2015 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.ui.vaadin.gwt.client.widget.controlbar;
  
  import info.magnolia.ui.vaadin.gwt.client.editor.dom.MgnlArea;
  import info.magnolia.ui.vaadin.gwt.client.widget.controlbar.eventmanager.ControlBarEventHandler;
  import info.magnolia.ui.vaadin.gwt.client.widget.controlbar.eventmanager.ControlBarEventManager;
  
  import com.google.gwt.core.client.GWT;
  import com.google.gwt.dom.client.NativeEvent;
  import com.google.gwt.user.client.DOM;
  import com.google.gwt.user.client.Element;
  import com.google.gwt.user.client.ui.FlowPanel;
  import com.google.gwt.user.client.ui.Label;
  
  /**
   * A Widget for adding components to area. Marks where a newly created component will be injected.
   * Is assembled by a {@link PlaceHolderBar} and an empty place holder area.
   */
  public class ComponentPlaceHolder extends FlowPanel {
  
      private final static String PLACEHOLDER_CLASS_NAME = "mgnlPlaceholder";
      private final static String PLACEHOLDER_ELEMENT_BOX_CLASS_NAME = "mgnlPlaceholderBox";
  
      private final MgnlArea listener;
  
      private PlaceHolderBar placeHolderBar;
  
      public ComponentPlaceHolder(MgnlArea area) throws IllegalArgumentException {
  
          this.listener = area;
          this.placeHolderBar = new PlaceHolderBar(area);
          setStyleName(AbstractBar.EDITOR_CLASS_NAME);
          addStyleName(PLACEHOLDER_CLASS_NAME);
  
          setVisible(false);
          initLayout();
      }
  
      protected void initLayout() {
          add(placeHolderBar);
          if (listener.isBoxPlaceHolder()) {
  
              Element element = DOM.createDiv();
              element.addClassName(AbstractBar.EDITOR_CLASS_NAME);
              element.addClassName(PLACEHOLDER_ELEMENT_BOX_CLASS_NAME);
              getElement().appendChild(element);
          }
      }
  
      @Override
      public void setVisible(boolean visible) {
          super.setVisible(visible);
          placeHolderBar.setVisible(visible);
      }
  
      @Override
      public void onAttach() {
          super.onAttach();
      }
  
      /**
       * A placeholder bar which resembles the {@link ComponentBar}.
       */
      private class PlaceHolderBar extends AbstractBar {
  
          private final MgnlArea listener;
  
         private ControlBarEventManager impl = GWT.create(ControlBarEventManager.class);
 
         public PlaceHolderBar(MgnlArea area) {
             super(area);
             this.listener = area;
 
             addStyleName(COMPONENT_CLASS_NAME);
 
             initLayout();
         }
 
         @Override
         protected String getLabel() {
             return listener.getPlaceHolderLabel();
         }
 
         @Override
         protected void createControls() {
 
             if (listener.hasAddComponentButton()) {
                 final Label add = new Label();
                 add.setStyleName(ICON_CLASS_NAME);
                 add.addStyleName(ADD_CLASS_NAME);
                 impl.addClickOrTouchHandler(this, new ControlBarEventHandler() {
                     @Override
                     public void handle(NativeEvent event) {
                         listener.createNewComponent();
                     }
                 });
                 addButton(add);
             }
         }
     }
 }