/*
    * 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.hadoop.chukwa.inputtools.jplugin;
  
  import java.util.Calendar;
  import java.util.Timer;
  import java.util.TimerTask;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.chukwa.util.DaemonWatcher;
  import org.apache.hadoop.chukwa.util.ExceptionUtil;
  
  public class JPluginAgent {
    private static Log log = LogFactory.getLog(JPluginAgent.class);
  
    private static class MetricsTimerTask extends TimerTask {
      @SuppressWarnings( { "unchecked" })
      private JPlugin plugin;
  
      @SuppressWarnings("unchecked")
      public MetricsTimerTask(JPlugin plugin) {
        this.plugin = plugin;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public void run() {
        try {
          ChukwaMetricsList metrics = plugin.getMetrics();
          String xml = metrics.toXml();
          log.info(xml);
        } catch (Throwable e) {
          log.error(e.getMessage(), e);
        }
      }
    }
  
    private static class StatusTimerTask extends TimerTask {
      @SuppressWarnings( { "unchecked" })
      private JPlugin plugin;
  
      @SuppressWarnings("unchecked")
      public StatusTimerTask(JPlugin plugin) {
        this.plugin = plugin;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public void run() {
        try {
          ChukwaMetricsList metrics = plugin.getStatus();
          String xml = metrics.toXml();
          log.info(xml);
        } catch (Throwable e) {
          log.error(e.getMessage(), e);
        }
      }
    }
  
    @SuppressWarnings("unchecked")
    public static void main(String[] args) {
      if (args.length < 1) {
        System.out
            .println("Usage: java -DPERIOD=nn JavaPluginAgent <class name> [parameters]");
        System.exit(0);
      }
  
      int period = -1;
      try {
        if (System.getProperty("PERIOD") != null) {
          period = Integer.parseInt(System.getProperty("PERIOD"));
        }
      } catch (NumberFormatException ex) {
        ex.printStackTrace();
        System.out.println("PERIOD should be numeric format of seconds.");
        System.exit(0);
      }
  
      JPlugin plugin = null;
      try {
        plugin = (JPlugin) Class.forName(args[0]).newInstance();
        plugin.init(args);
     } catch (Throwable e) {
       e.printStackTrace();
       System.exit(-1);
     }
 
     try {
       DaemonWatcher.createInstance(plugin.getRecordType() + "-data-loader");
     } catch (Exception e) {
       e.printStackTrace();
     }
 
     Calendar cal = Calendar.getInstance();
     long now = cal.getTime().getTime();
     cal.set(Calendar.SECOND, 3);
     cal.set(Calendar.MILLISECOND, 0);
     cal.add(Calendar.MINUTE, 1);
     long until = cal.getTime().getTime();
     try {
       if (period == -1) {
         new MetricsTimerTask(plugin).run();
       } else {
         Thread.sleep(until - now);
         Timer timer = new Timer();
         timer.scheduleAtFixedRate(new MetricsTimerTask(plugin), 0,
             period * 1000);
       }
     } catch (Exception ex) {
       log.debug(ExceptionUtil.getStackTrace(ex));
     }
   }
 }