/*
    * Copyright (C) 2007-2012 Argeo GmbH
    *
    * 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.argeo.jcr.proxy;
  
  import java.io.IOException;
  import java.io.InputStream;
  
  import javax.jcr.Node;
  import javax.jcr.Property;
  import javax.jcr.RepositoryException;
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.io.FilenameUtils;
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.argeo.jcr.ArgeoJcrException;
  import org.argeo.jcr.Bin;
  import org.argeo.jcr.JcrUtils;
  
  /** Wraps a proxy via HTTP */
  public class ResourceProxyServlet extends HttpServlet {
  	private static final long serialVersionUID = -8886549549223155801L;
  
  	private final static Log log = LogFactory
  			.getLog(ResourceProxyServlet.class);
  
  	private ResourceProxy proxy;
  
  	private String contentTypeCharset = "UTF-8";
  
  	@Override
  	protected void doGet(HttpServletRequest request,
  			HttpServletResponse response) throws ServletException, IOException {
  		String path = request.getPathInfo();
  
  		if (log.isTraceEnabled()) {
  			log.trace("path=" + path);
  			log.trace("UserPrincipal = " + request.getUserPrincipal().getName());
  			log.trace("SessionID = " + request.getSession(false).getId());
  			log.trace("ContextPath = " + request.getContextPath());
  			log.trace("ServletPath = " + request.getServletPath());
  			log.trace("PathInfo = " + request.getPathInfo());
  			log.trace("Method = " + request.getMethod());
  			log.trace("User-Agent = " + request.getHeader("User-Agent"));
  		}
  
  		Node node = null;
  		try {
  			node = proxy.proxy(path);
  			if (node == null)
  				response.sendError(404);
  			else
  				processResponse(node, response);
  		} finally {
  			if (node != null)
  				try {
  					JcrUtils.logoutQuietly(node.getSession());
  				} catch (RepositoryException e) {
  					// silent
  				}
  		}
  
  	}
  
  	/** Retrieve the content of the node. */
  	protected void processResponse(Node node, HttpServletResponse response) {
  //		Binary binary = null;
  //		InputStream in = null;
  		try(Bin binary = new Bin( node.getNode(Property.JCR_CONTENT)
  				.getProperty(Property.JCR_DATA));InputStream in = binary.getStream()) {
  			String fileName = node.getName();
  			String ext = FilenameUtils.getExtension(fileName);
  
  			// TODO use a more generic / standard approach
  			// see http://svn.apache.org/viewvc/tomcat/trunk/conf/web.xml
  			String contentType;
  			if ("xml".equals(ext))
  				contentType = "text/xml;charset=" + contentTypeCharset;
  			else if ("jar".equals(ext))
  				contentType = "application/java-archive";
  			else if ("zip".equals(ext))
  				contentType = "application/zip";
 			else if ("gz".equals(ext))
 				contentType = "application/x-gzip";
 			else if ("bz2".equals(ext))
 				contentType = "application/x-bzip2";
 			else if ("tar".equals(ext))
 				contentType = "application/x-tar";
 			else if ("rpm".equals(ext))
 				contentType = "application/x-redhat-package-manager";
 			else
 				contentType = "application/octet-stream";
 			contentType = contentType + ";name=\"" + fileName + "\"";
 			response.setHeader("Content-Disposition", "attachment; filename=\""
 					+ fileName + "\"");
 			response.setHeader("Expires", "0");
 			response.setHeader("Cache-Control", "no-cache, must-revalidate");
 			response.setHeader("Pragma", "no-cache");
 
 			response.setContentType(contentType);
 
 //			try {
 //				binary = node.getNode(Property.JCR_CONTENT)
 //						.getProperty(Property.JCR_DATA).getBinary();
 //			} catch (PathNotFoundException e) {
 //				log.error("Node " + node + " as no data under content");
 //				throw e;
 //			}
 //			in = binary.getStream();
 			IOUtils.copy(in, response.getOutputStream());
 		} catch (Exception e) {
 			throw new ArgeoJcrException("Cannot download " + node, e);
 //		} finally {
 //			IOUtils.closeQuietly(in);
 //			JcrUtils.closeQuietly(binary);
 		}
 	}
 
 	public void setProxy(ResourceProxy resourceProxy) {
 		this.proxy = resourceProxy;
 	}
 
 }