content: /*
   *  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 harry.corruptor;
  
  import java.util.Arrays;
  
  import harry.data.ResultSetRow;
  import harry.ddl.SchemaSpec;
  import harry.generators.DataGenerators;
  import harry.generators.PcgRSUFast;
  import harry.generators.EntropySource;
  import harry.model.Model;
  import harry.model.OpSelectors;
  import harry.operations.CompiledStatement;
  import harry.operations.WriteHelper;
  
  public class ShowValueCorruptor implements RowCorruptor
  {
      private final SchemaSpec schema;
      private final OpSelectors.Clock clock;
      private final EntropySource rng;
  
      public ShowValueCorruptor(SchemaSpec schemaSpec,
                                OpSelectors.Clock clock)
      {
          this.schema = schemaSpec;
          this.clock = clock;
          this.rng = new PcgRSUFast(1, 1);
      }
  
      // Can corrupt any row that has at least one written non-null value
      public boolean canCorrupt(ResultSetRow row)
      {
          for (int idx = 0; idx < row.lts.length; idx++)
          {
              if (row.lts[idx] == Model.NO_TIMESTAMP)
                  return true;
          }
          return false;
      }
  
      public CompiledStatement corrupt(ResultSetRow row)
      {
          long[] corruptedVds = new long[row.lts.length];
          Arrays.fill(corruptedVds, DataGenerators.UNSET_DESCR);
  
          int idx;
          do
          {
              idx = rng.nextInt(corruptedVds.length - 1);
          }
          while (row.lts[idx] != Model.NO_TIMESTAMP);
  
          corruptedVds[idx] = rng.next();
  
          // We do not know LTS of the deleted row. We could try inferring it, but that
          // still won't help since we can't use it anyways, since collisions between a
          // written value and tombstone are resolved in favour of tombstone.
          return WriteHelper.inflateInsert(schema, row.pd, row.cd, corruptedVds, null, clock.rts(clock.peek()));
      }
  }
  