/*
    * 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.hbase.filter;
  
  import static org.junit.Assert.assertEquals;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.hbase.Cell;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.Durability;
  import org.apache.hadoop.hbase.client.Put;
  import org.apache.hadoop.hbase.client.Result;
  import org.apache.hadoop.hbase.client.ResultScanner;
  import org.apache.hadoop.hbase.client.Scan;
  import org.apache.hadoop.hbase.client.Table;
  import org.apache.hadoop.hbase.filter.MultiRowRangeFilter.RowRange;
  import org.apache.hadoop.hbase.io.hfile.HFile;
  import org.apache.hadoop.hbase.testclassification.MediumTests;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.junit.AfterClass;
  import org.junit.BeforeClass;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  
  /*
   * This test is for the optimization added in HBASE-15243.
   * FilterList with two MultiRowRangeFilter's is constructed using Operator.MUST_PASS_ONE.
   */
  @Category(MediumTests.class)
  public class TestFilterListOrOperatorWithBlkCnt {
  
    private final static HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
    private static final Log LOG = LogFactory.getLog(TestFilterListOrOperatorWithBlkCnt.class);
    private byte[] family = Bytes.toBytes("family");
    private byte[] qf = Bytes.toBytes("qf");
    private byte[] value = Bytes.toBytes("val");
    private TableName tableName;
    private int numRows = 10000;
  
    /**
     * @throws Exception
     */
    @BeforeClass
    public static void setUpBeforeClass() throws Exception {
      long blkSize = 4096;
      /*
       * dfs block size is adjusted so that the specified number of rows would result in
       * multiple blocks (8 for this test).
       * Later in the test, assertion is made on the number of blocks read.
       */
      TEST_UTIL.getConfiguration().setLong("dfs.blocksize", blkSize);
      TEST_UTIL.getConfiguration().setLong("dfs.bytes-per-checksum", blkSize);
      TEST_UTIL.startMiniCluster();
    }
  
    /**
     * @throws Exception
     */
    @AfterClass
    public static void tearDownAfterClass() throws Exception {
      TEST_UTIL.shutdownMiniCluster();
    }
  
    private static long getBlkAccessCount() {
      return HFile.DATABLOCK_READ_COUNT.get();
    }
  
    @Test
    public void testMultiRowRangeWithFilterListOrOperatorWithBlkCnt() throws IOException {
      tableName = TableName.valueOf("TestMultiRowRangeFilterWithFilterListOrOperatorWithBlkCnt");
      Table ht = TEST_UTIL.createTable(tableName, family, Integer.MAX_VALUE);
      generateRows(numRows, ht, family, qf, value);
  
      Scan scan = new Scan();
      scan.setMaxVersions();
      long blocksStart = getBlkAccessCount();
  
      List<RowRange> ranges1 = new ArrayList<RowRange>();
     ranges1.add(new RowRange(Bytes.toBytes(10), true, Bytes.toBytes(15), false));
     ranges1.add(new RowRange(Bytes.toBytes(9980), true, Bytes.toBytes(9985), false));
 
     MultiRowRangeFilter filter1 = new MultiRowRangeFilter(ranges1);
 
     List<RowRange> ranges2 = new ArrayList<RowRange>();
     ranges2.add(new RowRange(Bytes.toBytes(15), true, Bytes.toBytes(20), false));
     ranges2.add(new RowRange(Bytes.toBytes(9985), true, Bytes.toBytes(9990), false));
 
     MultiRowRangeFilter filter2 = new MultiRowRangeFilter(ranges2);
 
     FilterList filterList = new FilterList(FilterList.Operator.MUST_PASS_ONE);
     filterList.addFilter(filter1);
     filterList.addFilter(filter2);
     scan.setFilter(filterList);
     int resultsSize = getResultsSize(ht, scan);
     LOG.info("found " + resultsSize + " results");
     List<Cell> results1 = getScanResult(Bytes.toBytes(10), Bytes.toBytes(20), ht);
     List<Cell> results2 = getScanResult(Bytes.toBytes(9980), Bytes.toBytes(9990), ht);
 
     assertEquals(results1.size() + results2.size(), resultsSize);
     long blocksEnd = getBlkAccessCount();
     long diff = blocksEnd - blocksStart;
     LOG.info("Diff in number of blocks " + diff);
     /*
      * Verify that we don't read all the blocks (8 in total).
      */
     assertEquals(4, diff);
 
     ht.close();
   }
 
   private void generateRows(int numberOfRows, Table ht, byte[] family, byte[] qf, byte[] value)
       throws IOException {
     for (int i = 0; i < numberOfRows; i++) {
       byte[] row = Bytes.toBytes(i);
       Put p = new Put(row);
       p.addColumn(family, qf, value);
       p.setDurability(Durability.SKIP_WAL);
       ht.put(p);
     }
     TEST_UTIL.flush();
   }
 
   private List<Cell> getScanResult(byte[] startRow, byte[] stopRow, Table ht) throws IOException {
     Scan scan = new Scan();
     scan.setMaxVersions();
     if(!Bytes.toString(startRow).isEmpty()) {
       scan.setStartRow(startRow);
     }
     if(!Bytes.toString(stopRow).isEmpty()) {
       scan.setStopRow(stopRow);
     }
     ResultScanner scanner = ht.getScanner(scan);
     List<Cell> kvList = new ArrayList<Cell>();
     Result r;
     while ((r = scanner.next()) != null) {
       for (Cell kv : r.listCells()) {
         kvList.add(kv);
       }
     }
     return kvList;
   }
 
   private int getResultsSize(Table ht, Scan scan) throws IOException {
     ResultScanner scanner = ht.getScanner(scan);
     List<Cell> results = new ArrayList<Cell>();
     Result r;
     while ((r = scanner.next()) != null) {
       for (Cell kv : r.listCells()) {
         results.add(kv);
       }
     }
     return results.size();
   }
 }