/*
    * 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.omid.transaction;
  
  import static org.testng.Assert.assertFalse;
  import static org.testng.Assert.assertNotNull;
  import static org.testng.Assert.assertTrue;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.List;
  
  import org.apache.hadoop.hbase.Cell;
  import org.apache.hadoop.hbase.CellUtil;
  import org.apache.hadoop.hbase.client.Get;
  import org.apache.hadoop.hbase.client.Put;
  import org.apache.hadoop.hbase.client.Result;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.testng.ITestContext;
  import org.testng.annotations.Test;
  
  @Test(groups = "sharedHBase")
  public class TestReadPath extends OmidTestBase {
  
      final byte[] family = Bytes.toBytes(TEST_FAMILY);
      final byte[] row = Bytes.toBytes("row");
      private final byte[] col = Bytes.toBytes("col1");
      final byte[] data = Bytes.toBytes("data");
      private final byte[] uncommitted = Bytes.toBytes("uncommitted");
  
      @Test(timeOut = 10_000)
      public void testReadInterleaved(ITestContext context) throws Exception {
          TransactionManager tm = newTransactionManager(context);
          TTable table = new TTable(connection, TEST_TABLE);
  
          // Put some data on the DB
          Transaction t1 = tm.begin();
          Transaction t2 = tm.begin();
  
          Put put = new Put(row);
          put.addColumn(family, col, data);
          table.put(t1, put);
          tm.commit(t1);
  
          Get get = new Get(row);
          Result result = table.get(t2, get);
          assertFalse(result.containsColumn(family, col), "Should be unable to read column");
      }
  
      @Test(timeOut = 10_000)
      public void testReadWithSeveralUncommitted(ITestContext context) throws Exception {
          TransactionManager tm = newTransactionManager(context);
          TTable table = new TTable(connection, TEST_TABLE);
  
          // Put some data on the DB
          Transaction t = tm.begin();
          Put put = new Put(row);
          put.addColumn(family, col, data);
          table.put(t, put);
          tm.commit(t);
          List<Transaction> running = new ArrayList<>();
  
          // Shade the data with uncommitted data
          for (int i = 0; i < 10; ++i) {
              t = tm.begin();
              put = new Put(row);
              put.addColumn(family, col, uncommitted);
              table.put(t, put);
              running.add(t);
          }
  
          // Try to read from row, it should ignore the uncommitted data and return the original committed value
          t = tm.begin();
          Get get = new Get(row);
          Result result = table.get(t, get);
          Cell cell = result.getColumnLatestCell(family, col);
          assertNotNull(cell, "KeyValue is null");
          byte[] value = CellUtil.cloneValue(cell);
          assertTrue(Arrays.equals(data, value), "Read data doesn't match");
          tm.commit(t);
  
          table.close();
  
          for (Transaction r : running) {
             tm.rollback(r);
         }
 
     }
 
 }