/*
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional information regarding
 * copyright ownership. The ASF licenses this file to You 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.apache.geode.modules.session;

import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;

/**
 *
 */
public class CommandServlet extends HttpServlet {

  private ServletContext context;

  /**
   * The standard servlet method overridden.
   *
   * @param request
   * @param response
   * @throws IOException
   */
  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws IOException, ServletException {

    QueryCommand cmd = QueryCommand.UNKNOWN;
    String param = request.getParameter("param");
    String value = request.getParameter("value");
    PrintWriter out = response.getWriter();

    String cmdStr = request.getParameter("cmd");
    if (cmdStr != null) {
      cmd = QueryCommand.valueOf(cmdStr);
    }

    HttpSession session;

    switch (cmd) {
      case SET:
        session = request.getSession();
        session.setAttribute(param, value);
        break;
      case GET:
        session = request.getSession();
        String val = (String) session.getAttribute(param);
        if (val != null) {
          out.write(val);
        }
        break;
      case INVALIDATE:
        session = request.getSession();
        session.invalidate();
        break;
      case CALLBACK:
        Callback c = (Callback) context.getAttribute("callback");
        c.call(request, response);
        break;
    }
  }

  /**
   * Save a reference to the ServletContext for later use.
   *
   * @param config
   */
  @Override
  public void init(ServletConfig config) {
    this.context = config.getServletContext();
  }
}