/**
    * This file Copyright (c) 2012-2013 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.layout;
  
  import info.magnolia.ui.vaadin.gwt.client.layout.thumbnaillayout.connector.ThumbnailLayoutState;
  import info.magnolia.ui.vaadin.gwt.client.layout.thumbnaillayout.rpc.ThumbnailLayoutClientRpc;
  import info.magnolia.ui.vaadin.gwt.client.layout.thumbnaillayout.rpc.ThumbnailLayoutServerRpc;
  import info.magnolia.ui.vaadin.gwt.client.layout.thumbnaillayout.shared.ThumbnailData;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.atomic.AtomicInteger;
  
  import org.apache.commons.lang.StringUtils;
  
  import com.google.common.collect.BiMap;
  import com.google.common.collect.HashBiMap;
  import com.vaadin.data.Container;
  import com.vaadin.data.Container.Ordered;
  import com.vaadin.server.Resource;
  import com.vaadin.ui.AbstractComponent;
  
  /**
   * Lazy layout of asset thumbnails.
   */
  public class LazyThumbnailLayout extends AbstractComponent implements Container.Viewer {
  
      private final List<ThumbnailSelectionListener> selectionListeners = new ArrayList<LazyThumbnailLayout.ThumbnailSelectionListener>();
  
      private final List<ThumbnailDblClickListener> dblClickListeners = new ArrayList<LazyThumbnailLayout.ThumbnailDblClickListener>();
  
      private final List<ThumbnailRightClickListener> rightClickListeners = new ArrayList<LazyThumbnailLayout.ThumbnailRightClickListener>();
  
      private Ordered container;
  
      // Maps thumbnailId to itemId
      private final BiMap<String, String> mapper = HashBiMap.create();
      private final AtomicInteger counter = new AtomicInteger();
  
      private String selectedItemId;
  
      private final ThumbnailLayoutServerRpc rpcHandler = new ThumbnailLayoutServerRpc() {
  
          @Override
          public void onThumbnailSelected(String id) {
              final Object itemId = mapper.get(id);
              if (itemId != null) {
                  LazyThumbnailLayout.this.onThumbnailSelected(itemId);
              }
          }
  
          @Override
          public void onThumbnailDoubleClicked(String id) {
              final Object itemId = mapper.get(id);
              if (itemId != null) {
                  LazyThumbnailLayout.this.onThumbnailDoubleClicked(itemId);
              }
          }
  
          @Override
          public void onThumbnailRightClicked(String id, int clickX, int clickY) {
              final Object itemId = mapper.get(id);
              if (itemId != null) {
                  LazyThumbnailLayout.this.onThumbnailRightClicked(itemId, clickX, clickY);
              }
          }
  
          @Override
         public void loadThumbnails(int amount) {
             getRpcProxy(ThumbnailLayoutClientRpc.class).addThumbnails(fetchThumbnails(amount));
             getRpcProxy(ThumbnailLayoutClientRpc.class).setSelected(mapper.inverse().get(selectedItemId));
         }
 
         @Override
         public void clearThumbnails() {
             LazyThumbnailLayout.this.clear();
         }
 
     };
 
     public LazyThumbnailLayout() {
         setImmediate(true);
         registerRpc(rpcHandler);
     }
 
     private void onThumbnailDoubleClicked(Object itemId) {
         for (final ThumbnailDblClickListener listener : dblClickListeners) {
             listener.onThumbnailDblClicked(String.valueOf(itemId));
         }
     }
 
     private void onThumbnailRightClicked(Object itemId, int clickX, int clickY) {
         for (final ThumbnailRightClickListener listener : rightClickListeners) {
             listener.onThumbnailRightClicked(String.valueOf(itemId), clickX, clickY);
         }
     }
 
     private void onThumbnailSelected(Object itemId) {
         for (final ThumbnailSelectionListener listener : selectionListeners) {
             listener.onThumbnailSelected(String.valueOf(itemId));
         }
     }
 
     private List<ThumbnailData> fetchThumbnails(int amount) {
         List<ThumbnailData> thumbnails = new ArrayList<ThumbnailData>();
         Object id = mapper.get(getState().lastQueried);
         if (id == null) {
             id = container.firstItemId();
         }
         int i = 0;
         while (id != null && i < amount) {
             Object resource = container.getContainerProperty(id, "thumbnail").getValue();
             boolean isRealResource = resource instanceof Resource;
             String thumbnailId = mapItemIdToThumbnailId((String) id);
             String iconFontId = isRealResource ? null : String.valueOf(resource);
             if (isRealResource) {
                 setResource(thumbnailId, (Resource) resource);
             }
             thumbnails.add(new ThumbnailData(thumbnailId, iconFontId, isRealResource));
             id = container.nextItemId(id);
             ++i;
         }
         getState().lastQueried = StringUtils.defaultString(mapItemIdToThumbnailId((String) id), "null");
         return thumbnails;
     }
 
     /**
      * Adds the itemId to the internal mapping or if it's already mapped returns the existing key.
      */
     private String mapItemIdToThumbnailId(String itemId) {
         if (itemId == null) {
             return null;
         }
         String thumbnailId = mapper.inverse().get(itemId);
         if (thumbnailId != null) {
             return thumbnailId;
         }
         thumbnailId = String.valueOf(counter.incrementAndGet());
         mapper.put(thumbnailId, itemId);
         return thumbnailId;
     }
 
     private void setThumbnailAmount(int thumbnailAmount) {
         getState().thumbnailAmount = Math.max(thumbnailAmount, 0);
     }
 
     public void setThumbnailSize(int width, int height) {
         getState().size.height = height;
         getState().size.width = width;
     }
 
     public int getThumbnailWidth() {
         return getState(false).size.width;
     }
 
     public int getThumbnailHeight() {
         return getState(false).size.height;
     }
 
     public void clear() {
         getState().resources.clear();
         getState().lastQueried = null;
         counter.set(0);
         mapper.clear();
     }
 
     public void refresh() {
         if (getState(false).thumbnailAmount > 0) {
             clear();
         }
         if (container != null) {
             setThumbnailAmount(container.size());
         }
     }
 
     public void addThumbnailSelectionListener(final ThumbnailSelectionListener listener) {
         this.selectionListeners.add(listener);
     }
 
     public void addDoubleClickListener(final ThumbnailDblClickListener listener) {
         this.dblClickListeners.add(listener);
     }
 
     public void addRightClickListener(final ThumbnailRightClickListener listener) {
         this.rightClickListeners.add(listener);
     }
 
     @Override
     public void setContainerDataSource(Container newDataSource) {
         if (newDataSource instanceof Ordered) {
             this.container = (Ordered) newDataSource;
             refresh();
         } else {
             throw new IllegalArgumentException("Container must be ordered.");
         }
     }
 
     @Override
     public Ordered getContainerDataSource() {
         return container;
     }
 
     @Override
     protected ThumbnailLayoutState getState() {
         return (ThumbnailLayoutState) super.getState();
     }
 
     @Override
     protected ThumbnailLayoutState getState(boolean markAsDirty) {
         return (ThumbnailLayoutState) super.getState(markAsDirty);
     }
 
     public void setSelectedItemId(String selectedItemId) {
         this.selectedItemId = selectedItemId;
     }
 
     /**
      * Listener interface for thumbnail selection.
      */
     public interface ThumbnailSelectionListener {
         void onThumbnailSelected(String itemId);
     }
 
     /**
      * Listener for thumbnail double clicks.
      */
     public interface ThumbnailDblClickListener {
         void onThumbnailDblClicked(String itemId);
     }
 
     /**
      * Listener for thumbnail right clicks.
      */
     public interface ThumbnailRightClickListener {
         void onThumbnailRightClicked(String itemId, int clickX, int clickY);
     }
 
     /**
      * Interface for the providers of the actual thumbnails.
      */
     public interface LazyThumbnailProvider {
 
         void refresh();
 
         int getThumbnailsAmount();
 
         List<Resource> getThumbnails(int amount);
 
     }
 
 }