/*
    * Licensed under the GPL License. You may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *   https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
    *
    * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
    * WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
    * PURPOSE.
   */
  package psiprobe;
  
  import java.nio.charset.StandardCharsets;
  
  import javax.servlet.ServletConfig;
  import javax.servlet.ServletException;
  import javax.servlet.annotation.WebServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.catalina.ContainerServlet;
  import org.apache.catalina.Wrapper;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.web.servlet.DispatcherServlet;
  
  import psiprobe.beans.ContainerWrapperBean;
  
  /**
   * Main dispatcher servlet. Spring default dispatcher servlet had to be superseded to handle
   * "privileged" application context features. The actual requirement is to capture passed Wrapper
   * instance into ContainerWrapperBean. Wrapper instance is our gateway to Tomcat.
   */
  @WebServlet
  public class ProbeServlet extends DispatcherServlet implements ContainerServlet {
  
    /** The Constant serialVersionUID. */
    private static final long serialVersionUID = 1L;
  
    /** The Constant logger. */
    private static final Logger logger = LoggerFactory.getLogger(ProbeServlet.class);
  
    /** The wrapper. */
    private transient Wrapper wrapper;
  
    @Override
    public Wrapper getWrapper() {
      return wrapper;
    }
  
    @Override
    public void setWrapper(Wrapper wrapper) {
      this.wrapper = wrapper;
      logger.info("setWrapper() called");
    }
  
    /**
     * Associates the {@link Wrapper} with the {@link ContainerWrapperBean}.
     *
     * @param config this servlet's configuration and initialization parameters
     *
     * @throws ServletException if the wrapper is null or another servlet-interrupting error occurs
     */
    @Override
    public void init(ServletConfig config) throws ServletException {
      super.init(config);
      if (wrapper == null) {
        throw new ServletException("Wrapper is null");
      }
      getContainerWrapperBean().setWrapper(wrapper);
    }
  
    /**
     * Dispatch.
     *
     * @param httpServletRequest the request
     * @param httpServletResponse the response
     *
     * @throws Exception if setting UTF-8 encoding fails or if the super implementation throws an
     *         exception
     */
    @Override
    protected void doDispatch(HttpServletRequest httpServletRequest,
        HttpServletResponse httpServletResponse) throws Exception {
      httpServletRequest.setCharacterEncoding(StandardCharsets.UTF_8.name());
      super.doDispatch(httpServletRequest, httpServletResponse);
    }
  
    @Override
    public void destroy() {
      getContainerWrapperBean().setWrapper(null);
      super.destroy();
    }
  
    /**
     * Gets the container wrapper bean.
     *
     * @return the container wrapper bean
     */
   protected ContainerWrapperBean getContainerWrapperBean() {
     return (ContainerWrapperBean) getWebApplicationContext().getBean("containerWrapper");
   }
 
 }