/*
 * 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.extraction.engine.datasource.record;


import java.io.IOException;
import java.util.Date;
import java.util.LinkedList;
import java.util.List;
import org.apache.hadoop.chukwa.extraction.engine.ChukwaRecord;
import org.apache.hadoop.chukwa.extraction.engine.ChukwaRecordKey;
import org.apache.hadoop.chukwa.extraction.engine.Record;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.SequenceFile;

public class ChukwaSequenceFileParser {

  public static List<Record> readData(String cluster, String dataSource,
      int maxRows, long t1, long t0, long maxOffset, String filter,
      String fileName, FileSystem fs, Configuration conf)
      throws MalformedFileFormat {

    // String source = "NameNode." + fileName;
    List<Record> records = new LinkedList<Record>();
    SequenceFile.Reader r = null;

    int lineCount = 0;
    if (filter != null) {
      filter = filter.toLowerCase();
    }

    try {

      if (!fs.exists(new Path(fileName))) {
        System.out.println("fileName not there!");
        return records;
      }
      System.out.println("NameNodeParser Open [" + fileName + "]");

      r = new SequenceFile.Reader(fs, new Path(fileName), conf);
      System.out.println("NameNodeParser Open2 [" + fileName + "]");

      long timestamp = 0;
      int listSize = 0;

      long offset = 0;

      // HdfsWriter.HdfsWriterKey key = new HdfsWriter.HdfsWriterKey();
      ChukwaRecordKey key = new ChukwaRecordKey();
      ChukwaRecord record = new ChukwaRecord();

      while (r.next(key, record)) {
        lineCount++;

        System.out.println("NameNodeParser Line ["
            + record.getValue(Record.bodyField) + "]");

        if (record != null) {
          timestamp = record.getTime();
          if (timestamp < t0) {
            System.out.println("Line not in range. Skipping: "
                + record.getValue(Record.bodyField));
            System.out.println("Search for: " + new Date(t0) + " is :"
                + new Date(timestamp));
            continue;
          } else if ((timestamp < t1) && (offset < maxOffset)) // JB (epochTS <
                                                               // maxDate)
          {

            System.out
                .println("In Range: " + record.getValue(Record.bodyField));
            boolean valid = false;

            if ((filter == null || filter.equals(""))) {
              valid = true;
            } else if (isValid(record, filter)) {
              valid = true;
            }

            if (valid) {
              records.add(record);
              record = new ChukwaRecord();
              listSize = records.size();
              if (listSize > maxRows) {
                records.remove(0);
                System.out.println("==========>>>>>REMOVING: "
                    + record.getValue(Record.bodyField));
              }
            } else {
              System.out
                  .println("In Range ==================>>>>>>>>> OUT Regex: "
                      + record.getValue(Record.bodyField));
            }

          } else {
            System.out.println("Line out of range. Stopping now: "
                + record.getValue(Record.bodyField));
            break;
          }
        }

      }
    } catch (IOException e) {
      e.printStackTrace();
    } finally {
      System.out.println("File: " + fileName + " Line count: " + lineCount);
      if (r != null) {
        try {
          r.close();
        } catch (IOException e) {
        }
      }

    }
    return records;
  }

  protected static boolean isValid(ChukwaRecord record, String filter) {
    String[] fields = record.getFields();
    for (String field : fields) {
      if (record.getValue(field).toLowerCase().indexOf(filter) >= 0) {
        return true;
      }
    }
    return false;
  }
}