/*
    * 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.database;
  
  import java.io.BufferedReader;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.nio.charset.Charset;
  import java.text.ParsePosition;
  import java.text.SimpleDateFormat;
  import java.util.Calendar;
  import java.util.Date;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.chukwa.util.DatabaseWriter;
  
  @SuppressWarnings("unused")
  public class Aggregator {
  
    private static Log log = LogFactory.getLog(Aggregator.class);
    private String table = null;
    private String jdbc = null;
    private int[] intervals;
    private long current = 0;
    private DatabaseWriter db = null;
  
    public Aggregator() {
      Calendar now = Calendar.getInstance();
      current = now.getTimeInMillis();
    }
  
    public static String getContents(File aFile) {
      StringBuffer contents = new StringBuffer();
      try {
        BufferedReader input = new BufferedReader(new InputStreamReader(new FileInputStream(aFile.getAbsolutePath()), Charset.forName("UTF-8")));
        try {
          String line = null; // not declared within while loop
          while ((line = input.readLine()) != null) {
            contents.append(line);
            contents.append(System.getProperty("line.separator"));
          }
        } finally {
          input.close();
        }
      } catch (IOException ex) {
        ex.printStackTrace();
      }
      return contents.toString();
    }
  
    public void process(long start, long end, String query) throws Throwable {
      try {
        Macro macroProcessor = new Macro(start, end, query);
        query = macroProcessor.toString();
        db.execute(query);
      } catch(Exception e) {
        log.error("Query: "+query);
        throw new Exception("Aggregation failed for: "+query);
      } finally {
        db.close();
      }
    }
  
    public void process(String query) throws Throwable {
      long start = current;
      long end = current;
      process(current, current, query);
    }
  
    public void setWriter(DatabaseWriter dbw) {
      db = dbw;
    }
  
    public static void main(String[] args) {
      long startTime = 0;
      long endTime = 0;
      long aggregatorStart = Calendar.getInstance().getTimeInMillis();
      long longest = 0;
      if(args.length>=4) {
       ParsePosition pp = new ParsePosition(0);
       SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm");
       String buffer = args[0]+" "+args[1];
       Date tmp = format.parse(buffer, pp);
       startTime = tmp.getTime();
       buffer = args[2]+" "+args[3];
       pp = new ParsePosition(0);
       tmp = format.parse(buffer, pp);
       endTime = tmp.getTime();
     }
     String longQuery = null;
     log.info("Aggregator started.");
     String cluster = System.getProperty("CLUSTER");
     if (cluster == null) {
       cluster = "unknown";
     }
     String queries = Aggregator.getContents(new File(System
         .getenv("CHUKWA_CONF_DIR")
         + File.separator + "aggregator.sql"));
     String[] query = queries.split("\n");
     while(startTime<=endTime) {
       for (int i = 0; i < query.length; i++) {
         if (query[i].indexOf("#") == 0) {
           log.debug("skipping: " + query[i]);
         } else if(!query[i].equals("")) {
           Aggregator dba = new Aggregator();
           dba.setWriter(new DatabaseWriter(cluster));
           long start = Calendar.getInstance().getTimeInMillis();
           try {
             if(startTime!=0 && endTime!=0) {
               dba.process(startTime, startTime, query[i]);
             } else {
               dba.process(query[i]);
             }
           } catch(Throwable e) {
             log.error("Invalid query:"+query[i]);
           }
           long end = Calendar.getInstance().getTimeInMillis();
           long duration = end - start;
           if (duration >= longest) {
             longest = duration;
             longQuery = query[i];
           }
         }
       }
       startTime = startTime + 5*60000;
     }
     long aggregatorEnd = Calendar.getInstance().getTimeInMillis();
     log.info("Longest running query: " + longQuery + " (" + (double) longest
         / 1000 + " seconds)");
     log.info("Total running time: ("+(double) (aggregatorEnd-aggregatorStart)/1000+" seconds)");
     log.info("Aggregator finished.");
   }
 
 }