/*
    * Copyright 2002-2013 the original author or authors.
    *
    * 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 org.springframework.web.socket.adapter.standard;
  
  import java.nio.ByteBuffer;
  import javax.websocket.CloseReason;
  import javax.websocket.Endpoint;
  import javax.websocket.EndpointConfig;
  import javax.websocket.MessageHandler;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import org.springframework.util.Assert;
  import org.springframework.web.socket.BinaryMessage;
  import org.springframework.web.socket.CloseStatus;
  import org.springframework.web.socket.PongMessage;
  import org.springframework.web.socket.TextMessage;
  import org.springframework.web.socket.WebSocketHandler;
  import org.springframework.web.socket.handler.ExceptionWebSocketHandlerDecorator;
  
  /**
   * Adapts a {@link WebSocketHandler} to the standard WebSocket for Java API.
   *
   * @author Rossen Stoyanchev
   * @since 4.0
   */
  public class StandardWebSocketHandlerAdapter extends Endpoint {
  
  	private static final Log logger = LogFactory.getLog(StandardWebSocketHandlerAdapter.class);
  
  	private final WebSocketHandler handler;
  
  	private final StandardWebSocketSession wsSession;
  
  
  	public StandardWebSocketHandlerAdapter(WebSocketHandler handler, StandardWebSocketSession wsSession) {
  		Assert.notNull(handler, "handler must not be null");
  		Assert.notNull(wsSession, "wsSession must not be null");
  		this.handler = handler;
  		this.wsSession = wsSession;
  	}
  
  
  	@Override
  	public void onOpen(final javax.websocket.Session session, EndpointConfig config) {
  
  		this.wsSession.initializeNativeSession(session);
  
  		if (this.handler.supportsPartialMessages()) {
  			session.addMessageHandler(new MessageHandler.Partial<String>() {
  				@Override
  				public void onMessage(String message, boolean isLast) {
  					handleTextMessage(session, message, isLast);
  				}
  			});
  			session.addMessageHandler(new MessageHandler.Partial<ByteBuffer>() {
  				@Override
  				public void onMessage(ByteBuffer message, boolean isLast) {
  					handleBinaryMessage(session, message, isLast);
  				}
  			});
  		}
  		else {
  			session.addMessageHandler(new MessageHandler.Whole<String>() {
  				@Override
  				public void onMessage(String message) {
  					handleTextMessage(session, message, true);
  				}
  			});
  			session.addMessageHandler(new MessageHandler.Whole<ByteBuffer>() {
  				@Override
  				public void onMessage(ByteBuffer message) {
  					handleBinaryMessage(session, message, true);
  				}
  			});
  		}
  
  		session.addMessageHandler(new MessageHandler.Whole<javax.websocket.PongMessage>() {
  			@Override
  			public void onMessage(javax.websocket.PongMessage message) {
  				handlePongMessage(session, message.getApplicationData());
  			}
  		});
  
 		try {
 			this.handler.afterConnectionEstablished(this.wsSession);
 		}
 		catch (Throwable t) {
 			ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, t, logger);
 			return;
 		}
 	}
 
 	private void handleTextMessage(javax.websocket.Session session, String payload, boolean isLast) {
 		TextMessage textMessage = new TextMessage(payload, isLast);
 		try {
 			this.handler.handleMessage(this.wsSession, textMessage);
 		}
 		catch (Throwable t) {
 			ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, t, logger);
 		}
 	}
 
 	private void handleBinaryMessage(javax.websocket.Session session, ByteBuffer payload, boolean isLast) {
 		BinaryMessage binaryMessage = new BinaryMessage(payload, isLast);
 		try {
 			this.handler.handleMessage(this.wsSession, binaryMessage);
 		}
 		catch (Throwable t) {
 			ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, t, logger);
 		}
 	}
 
 	private void handlePongMessage(javax.websocket.Session session, ByteBuffer payload) {
 		PongMessage pongMessage = new PongMessage(payload);
 		try {
 			this.handler.handleMessage(this.wsSession, pongMessage);
 		}
 		catch (Throwable t) {
 			ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, t, logger);
 		}
 	}
 
 	@Override
 	public void onClose(javax.websocket.Session session, CloseReason reason) {
 		CloseStatus closeStatus = new CloseStatus(reason.getCloseCode().getCode(), reason.getReasonPhrase());
 		try {
 			this.handler.afterConnectionClosed(this.wsSession, closeStatus);
 		}
 		catch (Throwable t) {
 			logger.error("Unhandled error for " + this.wsSession, t);
 		}
 	}
 
 	@Override
 	public void onError(javax.websocket.Session session, Throwable exception) {
 		try {
 			this.handler.handleTransportError(this.wsSession, exception);
 		}
 		catch (Throwable t) {
 			ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, t, logger);
 		}
 	}
 
 }