/*
 * The contents of this file are subject to the Open Software License
 * Version 3.0 (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.opensource.org/licenses/osl-3.0.txt
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 */

package org.mulgara.server;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Map;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


/**
 * A servlet for listing web services.
 *
 * @created Sep 6, 2008
 * @author Paula Gearon
 * @copyright © 2008 <a href="http://www.topazproject.org/">The Topaz Project</a>
 * @licence <a href="{@docRoot}/../../LICENCE.txt">Open Software License v3.0</a>
 */
public class ServiceListingServlet extends HttpServlet {

  /** Autogenerated serialization ID */
  private static final long serialVersionUID = -5568145649330453029L;

  /** A map of service names to paths. */
  private final Map<String,String> servicePaths;

  /** The default path to use when not using this class. */
  private final String defaultPath;

  /**
   * Creates the servlet for listing the given paths.
   * @param servicePaths The names of all the services.
   * @param defaultPath The default path to use when not using this servlet.
   */
  public ServiceListingServlet(Map<String,String> servicePaths, String defaultPath) throws IOException {
    this.servicePaths = servicePaths;
    this.defaultPath = defaultPath;
  }


  /**
   * Respond to a request for the servlet.
   * @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
   */
  protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    String path = req.getPathInfo();
    if (path.equals("/")) {
      // file request
      resp.setContentType("text/html");
      resp.setHeader("pragma", "no-cache");
      PrintWriter out = resp.getWriter();
      printPage(out);
      out.close();
    } else {
      resp.sendRedirect(defaultPath);
    }
  }


  /**
   * Provide a description for the servlet.
   * @see javax.servlet.GenericServlet#getServletInfo()
   */
  public String getServletInfo() {
    return "Service List";
  }


  /**
   * Outputs the list of service names and the paths to go to.
   * @param out Where to send the page.
   */
  private void printPage(PrintWriter out) {
    out.println("<!DOCTYPE html PUBLIC \"-//W3C//Dtd XHTML 1.0 Transitional//EN\" \"http://www.w3.org/tr/xhtml1/Dtd/xhtml1-transitional.dtd\">");
    out.println("<html xmlns=\"http://www.w3.org/1999/xhtml\">");
    out.println("<head>");
    out.println("<meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\" />");
    out.println("<title>Mulgara Web Services</title>");
    out.println("</head>");
    out.println("</body>");
    out.println("<h2>Available Services</h2>");
    out.println("<ul>");
    for (Map.Entry<String,String> service: servicePaths.entrySet()) {
      out.println("<li><a href=\"" + service.getValue() + "\">" + service.getKey() + "</a></li>");
    }
    out.println("</ul>");
    out.println("</body>");
    out.println("</html>");
  }

}