/**
    * This file Copyright (c) 2003-2014 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.cms.servlets;
  
  import info.magnolia.cms.util.RequestFormUtil;
  
  import java.io.PrintWriter;
  import java.io.StringWriter;
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.HashMap;
  import java.util.Map;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.beanutils.BeanUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * Default implementation of a MVCHandler. Calls the command (method) through reflection.
   * @author Philipp Bracher
   * @version $Id$
   */
  public abstract class MVCServletHandlerImpl implements MVCServletHandler {
  
      protected static final String VIEW_ERROR = "error"; //$NON-NLS-1$
  
      protected static final String VIEW_SUCCESS = "success"; //$NON-NLS-1$
  
      private static Logger log = LoggerFactory.getLogger(MVCServletHandlerImpl.class);
  
      protected HttpServletRequest request;
  
      protected HttpServletResponse response;
  
      protected Throwable exception;
  
      private String name;
  
      private String command;
  
      protected MVCServletHandlerImpl(String name, HttpServletRequest request, HttpServletResponse response) {
          this.name = name;
          this.setRequest(request);
          this.setResponse(response);
      }
  
      @Override
      public void init() {
          populateFromRequest(this);
      }
  
      protected void populateFromRequest(Object bean) {
          RequestFormUtil requestFormUtil = new RequestFormUtil(this.getRequest());
          Map parameters = new HashMap(); // needed, can't directly modify the map returned by request.getParameterMap()
          parameters.putAll(requestFormUtil.getParameters());
          parameters.putAll(requestFormUtil.getDocuments()); // handle uploaded files too
  
          try {
              // TODO : we could filter the parameters
              BeanUtils.populate(bean, parameters);
          }
          catch (Exception e) {
              log.error("can't set properties on the handler", e);
          }
     }
 
     /**
      * @see info.magnolia.cms.servlets.MVCServletHandler#getName()
      */
     @Override
     public String getName() {
         return name;
     }
 
     /**
      * Call the method through reflection.
      */
     @Override
     public String execute(String command) {
         String view = VIEW_ERROR;
         Method method;
 
         try {
             method = this.getClass().getMethod(command, new Class[]{});
             // method.setAccessible(true);
             view = (String) method.invoke(this, new Object[]{});
         }
         catch (InvocationTargetException e) {
             log.error("can't call command: " + command, e.getTargetException()); //$NON-NLS-1$
             exception = e.getTargetException();
         }
         catch (Exception e) {
             log.error("can't call command: " + command, e); //$NON-NLS-1$
             exception = e;
         }
 
         return view;
     }
 
     /**
      * @param request The request to set.
      */
     public void setRequest(HttpServletRequest request) {
         this.request = request;
     }
 
     /**
      * @return Returns the request.
      */
     public HttpServletRequest getRequest() {
         return request;
     }
 
     /**
      * @param response The response to set.
      */
     public void setResponse(HttpServletResponse response) {
         this.response = response;
     }
 
     /**
      * @return Returns the response.
      */
     public HttpServletResponse getResponse() {
         return response;
     }
 
     /**
      * @return Returns the command.
      */
     @Override
     public String getCommand() {
         return this.command;
     }
 
     /**
      * @param command The command to set.
      */
     public void setCommand(String command) {
         this.command = command;
     }
 
     /**
      * Getter for <code>exception</code>.
      * @return Returns the exception.
      */
     public Throwable getException() {
         return this.exception;
     }
 
     /**
      * Returns the stacktrace from the exception as a String.
      */
     public String getExceptionStackTrace() {
         if (this.exception == null) {
             return null;
         }
         StringWriter writer = new StringWriter();
         this.exception.printStackTrace(new PrintWriter(writer));
         return writer.toString();
     }
 }