/*

  * 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.giraph.conf;

 import org.apache.log4j.Logger;

 import java.io.BufferedWriter;

 import java.io.FileWriter;

 import java.io.IOException;

 import java.lang.reflect.Field;

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.Collections;

 import java.util.List;

 /**

  * Tracks all of the Giraph options

  */

 public class AllOptions {

   /**  logger object */

   private static final Logger LOG = Logger.getLogger(AllOptions.class);

   /** page name for the HTML page generation */

   private static final String PAGE_NAME = "Giraph Options";

   /** Don't construct */

   private AllOptions() { }

   /**

    * String representation of all of the options stored

    * @param options List of loaded options

    * @return string

    */

   private static String allOptionsString(List<AbstractConfOption> options) {

     Collections.sort(options);

     StringBuilder sb = new StringBuilder(options.size() * 30);

     sb.append("All Options:\n");

     ConfOptionType lastType = null;

     for (AbstractConfOption confOption : options) {

       if (!confOption.getType().equals(lastType)) {

         sb.append(confOption.getType().toString().toLowerCase()).append(":\n");

         lastType = confOption.getType();

       }

       sb.append(confOption);

     }

     return sb.toString();

   }

   /**

    * HTML String representation of all the options stored

    * @param options List of loaded options

    * @return String the HTML representation of the registered options

    */

   private static String allOptionsHTMLString(List<AbstractConfOption> options) {

     Collections.sort(options);

     StringBuilder sb = new StringBuilder(options.size() * 30);

     sb.append("<?xml version='1.0' encoding='UTF-8'?>\n" +

               "<!--\n" +

               "Licensed to the Apache Software Foundation (ASF) under one\n" +

               "or more contributor license agreements.  See the NOTICE file\n" +

               "distributed with this work for additional information\n" +

               "regarding copyright ownership.  The ASF licenses this file\n" +

               "to you under the Apache License, Version 2.0 (the\n" +

               "'License'); you may not use this file except in compliance\n" +

               "with the License.  You may obtain a copy of the License at\n" +

               "\n" +

               "    http://www.apache.org/licenses/LICENSE-2.0\n" +

               "\n" +

               "Unless required by applicable law or agreed to in writing,\n" +

               "software distributed under the License is distributed on an\n" +

               "'AS IS' BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY\n" +

               "KIND, either express or implied.  See the License for the\n" +

               "specific language governing permissions and limitations\n" +

               "under the License.\n" +

               "-->\n" +

               "\n" +

               "<document xmlns='http://maven.apache.org/XDOC/2.0'\n" +

               "          xmlns:xsi='http://www.w3.org/2001/" +

               "XMLSchema-instance'\n" +

               "          xsi:schemaLocation='" +

               "http://maven.apache.org/XDOC/2.0 " +

               " http://maven.apache.org/xsd/xdoc-2.0.xsd'>\n" +

               "  <properties>\n" +

               "    <title>" + PAGE_NAME + "</title>\n" +

               "  </properties>\n" +

               "  <body>\n" +

               "    <section name='" + PAGE_NAME + "'>\n" +

               "      <table border='0' style='width:110%; max-width:110%'>\n" +

               "       <tr>\n" +

               "        <th>label</th>\n" +

               "        <th>type</th>\n" +

               "        <th>default value</th>\n" +

               "        <th>description</th>\n" +

               "       </tr>\n");

     for (AbstractConfOption confOption : options) {

       String type = confOption.getType().toString().toLowerCase();

       sb.append("       <tr>\n");

       sb.append("         <td>" + confOption.getKey() + "</td>\n");

       sb.append("         <td>" + type  + "</td>\n");

       sb.append("         <td>" + confOption.getDefaultValueStr() + "</td>\n");

       sb.append("         <td>" + confOption.getDescription() + "</td>\n");

       sb.append("       </tr>\n");

     }

     sb.append("      </table>\n" +

               "    </section>\n" +

               "  </body>\n" +

               "</document>\n");

     return sb.toString();

   }

   /**

    * Command line utility to dump all Giraph options

    *

    * @param args cmdline args

    */

   public static void main(String[] args) throws IllegalAccessException {

     List<Field> fields = Arrays.asList(GiraphConstants.class.getFields());

     List<AbstractConfOption> options = new ArrayList<>();

     for (Field field : fields) {

       if (AbstractConfOption.class.isAssignableFrom(field.getType())) {

         AbstractConfOption option = (AbstractConfOption) field.get(null);

         options.add(option);

       }

     }

     // in case an options was specified, this option is treated as the output

     // file in which to write the HTML version of the list of available options

     if (args.length == 1) {

       String html = allOptionsHTMLString(options);

       try {

         FileWriter     fs  = new FileWriter(args[0]);

         BufferedWriter out = new BufferedWriter(fs);

         out.write(html);

         out.close();

       } catch (IOException e) {

         LOG.error("Error: " + e.getMessage());

       }

     }

     LOG.info(allOptionsString(options));

   }

 }