/*
    * Copyright 2000-2013 Vaadin Ltd.
    * 
    * Licensed under the Apache License, Version 2.0 (the "License"); you may not
    * use this file except in compliance with the License. You may obtain a copy of
    * the License at
    * 
    * http://www.apache.org/licenses/LICENSE-2.0
    * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations under
   * the License.
   */
  package com.vaadin.ui;
  
  import java.io.OutputStream;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.LinkedHashMap;
  import java.util.Map;
  import java.util.Map.Entry;
  
  import com.vaadin.event.Transferable;
  import com.vaadin.event.TransferableImpl;
  import com.vaadin.event.dd.DragSource;
  import com.vaadin.event.dd.DropHandler;
  import com.vaadin.event.dd.DropTarget;
  import com.vaadin.event.dd.TargetDetails;
  import com.vaadin.event.dd.TargetDetailsImpl;
  import com.vaadin.server.PaintException;
  import com.vaadin.server.PaintTarget;
  import com.vaadin.server.StreamVariable;
  import com.vaadin.shared.MouseEventDetails;
  import com.vaadin.shared.ui.dd.HorizontalDropLocation;
  import com.vaadin.shared.ui.dd.VerticalDropLocation;
  import com.vaadin.shared.ui.draganddropwrapper.DragAndDropWrapperConstants;
  
  @SuppressWarnings("serial")
  public class DragAndDropWrapper extends CustomComponent implements DropTarget,
          DragSource, LegacyComponent {
  
      public class WrapperTransferable extends TransferableImpl {
  
          private Html5File[] files;
  
          public WrapperTransferable(Component sourceComponent,
                  Map<String, Object> rawVariables) {
              super(sourceComponent, rawVariables);
              Integer fc = (Integer) rawVariables.get("filecount");
              if (fc != null) {
                  files = new Html5File[fc];
                  for (int i = 0; i < fc; i++) {
                      Html5File file = new Html5File(
                              (String) rawVariables.get("fn" + i), // name
                              (Integer) rawVariables.get("fs" + i), // size
                              (String) rawVariables.get("ft" + i)); // mime
                      String id = (String) rawVariables.get("fi" + i);
                      files[i] = file;
                      receivers.put(id, new ProxyReceiver(id, file));
                      markAsDirty(); // paint Receivers
                  }
              }
          }
  
          /**
           * The component in wrapper that is being dragged or null if the
           * transferable is not a component (most likely an html5 drag).
           * 
           * @return
           */
          public Component getDraggedComponent() {
              Component object = (Component) getData("component");
              return object;
          }
  
          /**
           * @return the mouse down event that started the drag and drop operation
           */
          public MouseEventDetails getMouseDownEvent() {
              return MouseEventDetails.deSerialize((String) getData("mouseDown"));
          }
  
          public Html5File[] getFiles() {
              return files;
          }
  
          public String getText() {
              String data = (String) getData("Text"); // IE, html5
              if (data == null) {
                  // check for "text/plain" (webkit)
                  data = (String) getData("text/plain");
              }
              return data;
          }
  
          public String getHtml() {
              String data = (String) getData("Html"); // IE, html5
             if (data == null) {
                 // check for "text/plain" (webkit)
                 data = (String) getData("text/html");
             }
             return data;
         }
 
     }
 
     private Map<String, ProxyReceiver> receivers = new HashMap<String, ProxyReceiver>();
 
     public class WrapperTargetDetails extends TargetDetailsImpl {
 
         public WrapperTargetDetails(Map<String, Object> rawDropData) {
             super(rawDropData, DragAndDropWrapper.this);
         }
 
         /**
          * @return the absolute position of wrapper on the page
          */
         public Integer getAbsoluteLeft() {
             return (Integer) getData("absoluteLeft");
         }
 
         /**
          * 
          * @return the absolute position of wrapper on the page
          */
         public Integer getAbsoluteTop() {
             return (Integer) getData("absoluteTop");
         }
 
         /**
          * @return details about the actual event that caused the event details.
          *         Practically mouse move or mouse up.
          */
         public MouseEventDetails getMouseEvent() {
             return MouseEventDetails
                     .deSerialize((String) getData("mouseEvent"));
         }
 
         /**
          * @return a detail about the drags vertical position over the wrapper.
          */
         public VerticalDropLocation getVerticalDropLocation() {
             return VerticalDropLocation
                     .valueOf((String) getData("verticalLocation"));
         }
 
         /**
          * @return a detail about the drags horizontal position over the
          *         wrapper.
          */
         public HorizontalDropLocation getHorizontalDropLocation() {
             return HorizontalDropLocation
                     .valueOf((String) getData("horizontalLocation"));
         }
 
     }
 
     public enum DragStartMode {
         /**
          * {@link DragAndDropWrapper} does not start drag events at all
          */
         NONE,
         /**
          * The component on which the drag started will be shown as drag image.
          */
         COMPONENT,
         /**
          * The whole wrapper is used as a drag image when dragging.
          */
         WRAPPER,
         /**
          * The whole wrapper is used to start an HTML5 drag.
          * 
          * NOTE: In Internet Explorer 6 to 8, this prevents user interactions
          * with the wrapper's contents. For example, clicking a button inside
          * the wrapper will no longer work.
          */
         HTML5,
     }
 
     private final Map<String, Object> html5DataFlavors = new LinkedHashMap<String, Object>();
     private DragStartMode dragStartMode = DragStartMode.NONE;
 
     /**
      * Wraps given component in a {@link DragAndDropWrapper}.
      * 
      * @param root
      *            the component to be wrapped
      */
     public DragAndDropWrapper(Component root) {
         super(root);
     }
 
     /**
      * Sets data flavors available in the DragAndDropWrapper is used to start an
      * HTML5 style drags. Most commonly the "Text" flavor should be set.
      * Multiple data types can be set.
      * 
      * @param type
      *            the string identifier of the drag "payload". E.g. "Text" or
      *            "text/html"
      * @param value
      *            the value
      */
     public void setHTML5DataFlavor(String type, Object value) {
         html5DataFlavors.put(type, value);
         markAsDirty();
     }
 
     @Override
     public void changeVariables(Object source, Map<String, Object> variables) {
         // TODO Remove once LegacyComponent is no longer implemented
     }
 
     @Override
     public void paintContent(PaintTarget target) throws PaintException {
         target.addAttribute(DragAndDropWrapperConstants.DRAG_START_MODE,
                 dragStartMode.ordinal());
         if (getDropHandler() != null) {
             getDropHandler().getAcceptCriterion().paint(target);
         }
         if (receivers != null && receivers.size() > 0) {
             for (Iterator<Entry<String, ProxyReceiver>> it = receivers
                     .entrySet().iterator(); it.hasNext();) {
                 Entry<String, ProxyReceiver> entry = it.next();
                 String id = entry.getKey();
                 ProxyReceiver proxyReceiver = entry.getValue();
                 Html5File html5File = proxyReceiver.file;
                 if (html5File.getStreamVariable() != null) {
                     target.addVariable(this, "rec-" + id, new ProxyReceiver(id,
                             html5File));
                     // these are cleaned from receivers once the upload has
                     // started
                 } else {
                     // instructs the client side not to send the file
                     target.addVariable(this, "rec-" + id, (String) null);
                     // forget the file from subsequent paints
                     it.remove();
                 }
             }
         }
         target.addAttribute(DragAndDropWrapperConstants.HTML5_DATA_FLAVORS,
                 html5DataFlavors);
     }
 
     private DropHandler dropHandler;
 
     @Override
     public DropHandler getDropHandler() {
         return dropHandler;
     }
 
     public void setDropHandler(DropHandler dropHandler) {
         this.dropHandler = dropHandler;
         markAsDirty();
     }
 
     @Override
     public TargetDetails translateDropTargetDetails(
             Map<String, Object> clientVariables) {
         return new WrapperTargetDetails(clientVariables);
     }
 
     @Override
     public Transferable getTransferable(final Map<String, Object> rawVariables) {
         return new WrapperTransferable(this, rawVariables);
     }
 
     public void setDragStartMode(DragStartMode dragStartMode) {
         this.dragStartMode = dragStartMode;
         markAsDirty();
     }
 
     public DragStartMode getDragStartMode() {
         return dragStartMode;
     }
 
     final class ProxyReceiver implements StreamVariable {
 
         private String id;
         private Html5File file;
 
         public ProxyReceiver(String id, Html5File file) {
             this.id = id;
             this.file = file;
         }
 
         private boolean listenProgressOfUploadedFile;
 
         @Override
         public OutputStream getOutputStream() {
             if (file.getStreamVariable() == null) {
                 return null;
             }
             return file.getStreamVariable().getOutputStream();
         }
 
         @Override
         public boolean listenProgress() {
             return file.getStreamVariable().listenProgress();
         }
 
         @Override
         public void onProgress(StreamingProgressEvent event) {
             file.getStreamVariable().onProgress(
                     new ReceivingEventWrapper(event));
         }
 
         @Override
         public void streamingStarted(StreamingStartEvent event) {
             listenProgressOfUploadedFile = file.getStreamVariable() != null;
             if (listenProgressOfUploadedFile) {
                 file.getStreamVariable().streamingStarted(
                         new ReceivingEventWrapper(event));
             }
             // no need tell to the client about this receiver on next paint
             receivers.remove(id);
             // let the terminal GC the streamvariable and not to accept other
             // file uploads to this variable
             event.disposeStreamVariable();
         }
 
         @Override
         public void streamingFinished(StreamingEndEvent event) {
             if (listenProgressOfUploadedFile) {
                 file.getStreamVariable().streamingFinished(
                         new ReceivingEventWrapper(event));
             }
         }
 
         @Override
         public void streamingFailed(final StreamingErrorEvent event) {
             if (listenProgressOfUploadedFile) {
                 file.getStreamVariable().streamingFailed(
                         new ReceivingEventWrapper(event));
             }
         }
 
         @Override
         public boolean isInterrupted() {
             return file.getStreamVariable().isInterrupted();
         }
 
         /*
          * With XHR2 file posts we can't provide as much information from the
          * terminal as with multipart request. This helper class wraps the
          * terminal event and provides the lacking information from the
          * Html5File.
          */
         class ReceivingEventWrapper implements StreamingErrorEvent,
                 StreamingEndEvent, StreamingStartEvent, StreamingProgressEvent {
 
             private StreamingEvent wrappedEvent;
 
             ReceivingEventWrapper(StreamingEvent e) {
                 wrappedEvent = e;
             }
 
             @Override
             public String getMimeType() {
                 return file.getType();
             }
 
             @Override
             public String getFileName() {
                 return file.getFileName();
             }
 
             @Override
             public long getContentLength() {
                 return file.getFileSize();
             }
 
             public StreamVariable getReceiver() {
                 return ProxyReceiver.this;
             }
 
             @Override
             public Exception getException() {
                 if (wrappedEvent instanceof StreamingErrorEvent) {
                     return ((StreamingErrorEvent) wrappedEvent).getException();
                 }
                 return null;
             }
 
             @Override
             public long getBytesReceived() {
                 return wrappedEvent.getBytesReceived();
             }
 
             /**
              * Calling this method has no effect. DD files are receive only once
              * anyway.
              */
             @Override
             public void disposeStreamVariable() {
 
             }
         }
 
     }
 
 }