/*
    *
    * 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.io.hfile;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertTrue;
  
  import java.io.ByteArrayInputStream;
  import java.io.DataInputStream;
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  import java.util.Random;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.FSDataInputStream;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.KeyValue;
  import org.apache.hadoop.hbase.KeyValue.KVComparator;
  import org.apache.hadoop.hbase.testclassification.SmallTests;
  import org.apache.hadoop.hbase.Tag;
  import org.apache.hadoop.hbase.io.compress.Compression;
  import org.apache.hadoop.hbase.io.compress.Compression.Algorithm;
  import org.apache.hadoop.hbase.io.encoding.DataBlockEncoding;
  import org.apache.hadoop.hbase.io.hfile.HFile.FileInfo;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.apache.hadoop.hbase.util.Writables;
  import org.apache.hadoop.io.Text;
  import org.apache.hadoop.io.WritableUtils;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  import org.junit.runner.RunWith;
  import org.junit.runners.Parameterized;
  import org.junit.runners.Parameterized.Parameters;
  
  /**
   * Testing writing a version 3 {@link HFile}. This is a low-level test written
   * during the development of {@link HFileWriterV3}.
   */
  @RunWith(Parameterized.class)
  @Category(SmallTests.class)
  public class TestHFileWriterV3 {
  
    private static final Log LOG = LogFactory.getLog(TestHFileWriterV3.class);
  
    private static final HBaseTestingUtility TEST_UTIL =
        new HBaseTestingUtility();
  
    private Configuration conf;
    private FileSystem fs;
    private boolean useTags;
    public TestHFileWriterV3(boolean useTags) {
      this.useTags = useTags;
    }
    @Parameters
    public static Collection<Object[]> parameters() {
      return HBaseTestingUtility.BOOLEAN_PARAMETERIZED;
    }
  
    @Before
    public void setUp() throws IOException {
      conf = TEST_UTIL.getConfiguration();
      fs = FileSystem.get(conf);
    }
  
    @Test
    public void testHFileFormatV3() throws IOException {
      testHFileFormatV3Internals(useTags);
    }
  
    private void testHFileFormatV3Internals(boolean useTags) throws IOException {
      Path hfilePath = new Path(TEST_UTIL.getDataTestDir(), "testHFileFormatV3");
      final Compression.Algorithm compressAlgo = Compression.Algorithm.GZ;
     final int entryCount = 10000;
     writeDataAndReadFromHFile(hfilePath, compressAlgo, entryCount, false, useTags);
   }
 
   @Test
   public void testMidKeyInHFile() throws IOException{
     testMidKeyInHFileInternals(useTags);
   }
 
   private void testMidKeyInHFileInternals(boolean useTags) throws IOException {
     Path hfilePath = new Path(TEST_UTIL.getDataTestDir(),
     "testMidKeyInHFile");
     Compression.Algorithm compressAlgo = Compression.Algorithm.NONE;
     int entryCount = 50000;
     writeDataAndReadFromHFile(hfilePath, compressAlgo, entryCount, true, useTags);
   }
 
   private void writeDataAndReadFromHFile(Path hfilePath,
       Algorithm compressAlgo, int entryCount, boolean findMidKey, boolean useTags) throws IOException {
     HFileContext context = new HFileContextBuilder()
       .withBlockSize(4096)
       .withIncludesTags(useTags)
       .withDataBlockEncoding(DataBlockEncoding.NONE)
       .withCompression(compressAlgo).build();
     HFileWriterV3 writer = (HFileWriterV3)
         new HFileWriterV3.WriterFactoryV3(conf, new CacheConfig(conf))
             .withPath(fs, hfilePath)
             .withFileContext(context)
             .withComparator(KeyValue.COMPARATOR)
             .create();
 
     Random rand = new Random(9713312); // Just a fixed seed.
     List<KeyValue> keyValues = new ArrayList<KeyValue>(entryCount);
 
     for (int i = 0; i < entryCount; ++i) {
       byte[] keyBytes = TestHFileWriterV2.randomOrderedKey(rand, i);
 
       // A random-length random value.
       byte[] valueBytes = TestHFileWriterV2.randomValue(rand);
       KeyValue keyValue = null;
       if (useTags) {
         ArrayList<Tag> tags = new ArrayList<Tag>();
         for (int j = 0; j < 1 + rand.nextInt(4); j++) {
           byte[] tagBytes = new byte[16];
           rand.nextBytes(tagBytes);
           tags.add(new Tag((byte) 1, tagBytes));
         }
         keyValue = new KeyValue(keyBytes, null, null, HConstants.LATEST_TIMESTAMP,
             valueBytes, tags);
       } else {
         keyValue = new KeyValue(keyBytes, null, null, HConstants.LATEST_TIMESTAMP,
             valueBytes);
       }
       writer.append(keyValue);
       keyValues.add(keyValue);
     }
 
     // Add in an arbitrary order. They will be sorted lexicographically by
     // the key.
     writer.appendMetaBlock("CAPITAL_OF_USA", new Text("Washington, D.C."));
     writer.appendMetaBlock("CAPITAL_OF_RUSSIA", new Text("Moscow"));
     writer.appendMetaBlock("CAPITAL_OF_FRANCE", new Text("Paris"));
 
     writer.close();
 
 
     FSDataInputStream fsdis = fs.open(hfilePath);
 
     long fileSize = fs.getFileStatus(hfilePath).getLen();
     FixedFileTrailer trailer =
         FixedFileTrailer.readFromStream(fsdis, fileSize);
 
     assertEquals(3, trailer.getMajorVersion());
     assertEquals(entryCount, trailer.getEntryCount());
     HFileContext meta = new HFileContextBuilder()
       .withCompression(compressAlgo)
       .withIncludesMvcc(false)
       .withIncludesTags(useTags)
       .withDataBlockEncoding(DataBlockEncoding.NONE)
       .withHBaseCheckSum(true).build();
     HFileBlock.FSReader blockReader =
         new HFileBlock.FSReaderImpl(fsdis, fileSize, meta);
  // Comparator class name is stored in the trailer in version 2.
     KVComparator comparator = trailer.createComparator();
     HFileBlockIndex.BlockIndexReader dataBlockIndexReader =
         new HFileBlockIndex.BlockIndexReader(comparator,
             trailer.getNumDataIndexLevels());
     HFileBlockIndex.BlockIndexReader metaBlockIndexReader =
         new HFileBlockIndex.BlockIndexReader(
             KeyValue.RAW_COMPARATOR, 1);
 
     HFileBlock.BlockIterator blockIter = blockReader.blockRange(
         trailer.getLoadOnOpenDataOffset(),
         fileSize - trailer.getTrailerSize());
     // Data index. We also read statistics about the block index written after
     // the root level.
     dataBlockIndexReader.readMultiLevelIndexRoot(
         blockIter.nextBlockWithBlockType(BlockType.ROOT_INDEX), trailer.getDataIndexCount());
 
     if (findMidKey) {
       byte[] midkey = dataBlockIndexReader.midkey();
       assertNotNull("Midkey should not be null", midkey);
     }
 
     // Meta index.
     metaBlockIndexReader.readRootIndex(
         blockIter.nextBlockWithBlockType(BlockType.ROOT_INDEX)
           .getByteStream(), trailer.getMetaIndexCount());
     // File info
     FileInfo fileInfo = new FileInfo();
     fileInfo.read(blockIter.nextBlockWithBlockType(BlockType.FILE_INFO).getByteStream());
     byte [] keyValueFormatVersion = fileInfo.get(
         HFileWriterV3.KEY_VALUE_VERSION);
     boolean includeMemstoreTS = keyValueFormatVersion != null &&
         Bytes.toInt(keyValueFormatVersion) > 0;
 
     // Counters for the number of key/value pairs and the number of blocks
     int entriesRead = 0;
     int blocksRead = 0;
     long memstoreTS = 0;
 
     // Scan blocks the way the reader would scan them
     fsdis.seek(0);
     long curBlockPos = 0;
     while (curBlockPos <= trailer.getLastDataBlockOffset()) {
       HFileBlock block = blockReader.readBlockData(curBlockPos, -1, false, false)
         .unpack(context, blockReader);
       assertEquals(BlockType.DATA, block.getBlockType());
       ByteBuffer buf = block.getBufferWithoutHeader();
       int keyLen = -1;
       while (buf.hasRemaining()) {
 
         keyLen = buf.getInt();
 
         int valueLen = buf.getInt();
 
         byte[] key = new byte[keyLen];
         buf.get(key);
 
         byte[] value = new byte[valueLen];
         buf.get(value);
         byte[] tagValue = null;
         if (useTags) {
           int tagLen = ((buf.get() & 0xff) << 8) ^ (buf.get() & 0xff);
           tagValue = new byte[tagLen];
           buf.get(tagValue);
         }
 
         if (includeMemstoreTS) {
           ByteArrayInputStream byte_input = new ByteArrayInputStream(buf.array(), buf.arrayOffset()
               + buf.position(), buf.remaining());
           DataInputStream data_input = new DataInputStream(byte_input);
 
           memstoreTS = WritableUtils.readVLong(data_input);
           buf.position(buf.position() + WritableUtils.getVIntSize(memstoreTS));
         }
 
         // A brute-force check to see that all keys and values are correct.
         assertTrue(Bytes.compareTo(key, keyValues.get(entriesRead).getKey()) == 0);
         assertTrue(Bytes.compareTo(value, keyValues.get(entriesRead).getValue()) == 0);
         if (useTags) {
           assertNotNull(tagValue);
           KeyValue tkv =  keyValues.get(entriesRead);
           assertEquals(tagValue.length, tkv.getTagsLength());
           assertTrue(Bytes.compareTo(tagValue, 0, tagValue.length, tkv.getTagsArray(),
               tkv.getTagsOffset(), tkv.getTagsLength()) == 0);
         }
         ++entriesRead;
       }
       ++blocksRead;
       curBlockPos += block.getOnDiskSizeWithHeader();
     }
     LOG.info("Finished reading: entries=" + entriesRead + ", blocksRead="
         + blocksRead);
     assertEquals(entryCount, entriesRead);
 
     // Meta blocks. We can scan until the load-on-open data offset (which is
     // the root block index offset in version 2) because we are not testing
     // intermediate-level index blocks here.
 
     int metaCounter = 0;
     while (fsdis.getPos() < trailer.getLoadOnOpenDataOffset()) {
       LOG.info("Current offset: " + fsdis.getPos() + ", scanning until " +
           trailer.getLoadOnOpenDataOffset());
       HFileBlock block = blockReader.readBlockData(curBlockPos, -1, false, false)
         .unpack(context, blockReader);
       assertEquals(BlockType.META, block.getBlockType());
       Text t = new Text();
       ByteBuffer buf = block.getBufferWithoutHeader();
       if (Writables.getWritable(buf.array(), buf.arrayOffset(), buf.limit(), t) == null) {
         throw new IOException("Failed to deserialize block " + this +
             " into a " + t.getClass().getSimpleName());
       }
       Text expectedText =
           (metaCounter == 0 ? new Text("Paris") : metaCounter == 1 ? new Text(
               "Moscow") : new Text("Washington, D.C."));
       assertEquals(expectedText, t);
       LOG.info("Read meta block data: " + t);
       ++metaCounter;
       curBlockPos += block.getOnDiskSizeWithHeader();
     }
 
     fsdis.close();
   }
 
 }