/*

 *   SONEWS News Server

 *   see AUTHORS for the list of contributors

 *

 *   This program is free software: you can redistribute it and/or modify

 *   it under the terms of the GNU General Public License as published by

 *   the Free Software Foundation, either version 3 of the License, or

 *   (at your option) any later version.

 *

 *   This program is distributed in the hope that it will be useful,

 *   but WITHOUT ANY WARRANTY; without even the implied warranty of

 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *   GNU General Public License for more details.

 *

 *   You should have received a copy of the GNU General Public License

 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

package org.sonews.web;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import java.util.Set;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.sonews.util.StringTemplate;

import org.sonews.util.io.Resource;

/**

 * Servlet providing a configuration web interface.

 * @author Christian Lins

 * @since sonews/0.5.0

 */

public class SonewsConfigServlet extends AbstractSonewsServlet

{

  private static final long serialVersionUID = 2432543253L;

  @Override

  public void doGet(HttpServletRequest req, HttpServletResponse resp)

    throws IOException

  {

    synchronized(this)

    {

      connectToNewsserver();

      String which = req.getParameter("which");

      if(which != null && which.equals("config"))

      {

        whichConfig(req, resp);

      }

      else if(which != null && which.equals("groupadd"))

      {

        whichGroupAdd(req, resp);

      }

      else if(which != null && which.equals("groupdelete"))

      {

        whichGroupDelete(req, resp);

      }

      else

      {

        whichNone(req, resp);

      }

      disconnectFromNewsserver();

    }

  }

  private void whichConfig(HttpServletRequest req, HttpServletResponse resp)

    throws IOException

  {

    StringBuilder keys = new StringBuilder();

    Set pnames = req.getParameterMap().keySet();

    for(Object obj : pnames)

    {

      String pname = (String)obj;

      if(pname.startsWith("configkey:"))

      {

        String value = req.getParameter(pname);

        String key   = pname.split(":")[1];

        if(!value.equals("<not set>"))

        {

          printlnToNewsserver("XDAEMON SET " + key + " " + value);

          readlnFromNewsserver();

          keys.append(key); 

          keys.append("<br/>");

        }

      }

    }

    StringTemplate tmpl = getTemplate("ConfigUpdated.tmpl");

    tmpl.set("UPDATED_KEYS", keys.toString());

    resp.setStatus(HttpServletResponse.SC_OK);

    resp.getWriter().println(tmpl.toString());

    resp.getWriter().flush();

  }

  private void whichGroupAdd(HttpServletRequest req, HttpServletResponse resp)

    throws IOException

  {

    String[] groupnames = req.getParameter("groups").split("\n");

    for(String groupname : groupnames)

    {

      groupname = groupname.trim();

      if(groupname.equals(""))

      {

        continue;

      }

      printlnToNewsserver("XDAEMON GROUPADD " + groupname + " 0");

      String line = readlnFromNewsserver();

      if(!line.startsWith("200 "))

      {

        System.out.println("Warning " + groupname + " probably not created!");

      }

    }

    StringTemplate tmpl = getTemplate("GroupAdded.tmpl");

    tmpl.set("GROUP", req.getParameter("groups"));

    resp.setStatus(HttpServletResponse.SC_OK);

    resp.getWriter().println(tmpl.toString());

    resp.getWriter().flush();

  }

  private void whichGroupDelete(HttpServletRequest req, HttpServletResponse resp)

    throws IOException

  {

    String groupname = req.getParameter("group");

    printlnToNewsserver("XDAEMON GROUPDEL " + groupname);

    String line = readlnFromNewsserver();

    if(!line.startsWith("200 "))

      throw new IOException(line);

    StringTemplate tmpl = getTemplate("GroupDeleted.tmpl");

    tmpl.set("GROUP", groupname);

    resp.setStatus(HttpServletResponse.SC_OK);

    resp.getWriter().println(tmpl.toString());

    resp.getWriter().flush();

  }

  private void whichNone(HttpServletRequest req, HttpServletResponse resp)

    throws IOException

  {

    StringTemplate tmpl = getTemplate("SonewsConfigServlet.tmpl");

    // Retrieve config keys from server

    List<String> configKeys = new ArrayList<String>();

    printlnToNewsserver("XDAEMON LIST CONFIGKEYS");

    String line = readlnFromNewsserver();

    if(!line.startsWith("200 "))

      throw new IOException("XDAEMON command not supported!");

    for(;;)

    {

      line = readlnFromNewsserver();

      if(line.equals("."))

        break;

      else

        configKeys.add(line);

    }

    // Construct config table

    StringBuilder strb = new StringBuilder();

    for(String key : configKeys)

    {

      strb.append("<tr><td><code>");

      strb.append(key);

      strb.append("</code></td><td>");

      // Retrieve config value from server

      String value = "<not set>";

      printlnToNewsserver("XDAEMON GET " + key);

      line = readlnFromNewsserver();

      if(line.startsWith("200 "))

      {

        value = readlnFromNewsserver();

        readlnFromNewsserver(); // Read the "."

      }

      strb.append("<input type=text name=\"configkey:");

      strb.append(key);

      strb.append("\" value=\"");

      strb.append(value);

      strb.append("\"/></td></tr>");

    }

    tmpl.set("CONFIG", strb.toString());

    // Retrieve served newsgroup names from server

    List<String> groups = new ArrayList<String>();

    printlnToNewsserver("LIST");

    line = readlnFromNewsserver();

    if(line.startsWith("215 "))

    {

      for(;;)

      {

        line = readlnFromNewsserver();

        if(line.equals("."))

        {

          break;

        }

        else

        {

          groups.add(line.split(" ")[0]);

        }

      }

    }

    else

      throw new IOException("Error issuing LIST command!");

    // Construct groups list

    StringTemplate tmplGroupList = new StringTemplate(

      Resource.getAsString("org/sonews/web/tmpl/GroupList.tmpl", true));

    strb = new StringBuilder();

    for(String group : groups)

    {

      tmplGroupList.set("GROUPNAME", group);

      strb.append(tmplGroupList.toString());

    }

    tmpl.set("GROUP", strb.toString());

    // Set server name

    tmpl.set("SERVERNAME", hello.split(" ")[2]);

    tmpl.set("TITLE", "Configuration");

    resp.getWriter().println(tmpl.toString());

    resp.getWriter().flush();

    resp.setStatus(HttpServletResponse.SC_OK);

  }

}