content: package org.apache.cassandra.stress.operations.userdefined;
  /*
   * 
   * 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.
   * 
   */
  
  import com.datastax.driver.core.BoundStatement;
  import com.datastax.driver.core.ColumnDefinitions;
  import com.datastax.driver.core.DataType;
  import com.datastax.driver.core.LocalDate;
  import com.datastax.driver.core.PreparedStatement;
  import com.datastax.driver.core.ResultSet;
  import org.antlr.runtime.RecognitionException;
  import org.apache.cassandra.cql3.CQLFragmentParser;
  import org.apache.cassandra.cql3.ColumnIdentifier;
  import org.apache.cassandra.cql3.CqlParser;
  import org.apache.cassandra.cql3.conditions.ColumnCondition;
  import org.apache.cassandra.cql3.statements.ModificationStatement;
  import org.apache.cassandra.db.ConsistencyLevel;
  import org.apache.cassandra.stress.generate.DistributionFixed;
  import org.apache.cassandra.stress.generate.PartitionGenerator;
  import org.apache.cassandra.stress.generate.Row;
  import org.apache.cassandra.stress.generate.SeedManager;
  import org.apache.cassandra.stress.generate.values.Generator;
  import org.apache.cassandra.stress.report.Timer;
  import org.apache.cassandra.stress.settings.StressSettings;
  import org.apache.cassandra.stress.util.JavaDriverClient;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.stream.Collectors;
  
  import com.google.common.collect.ImmutableList;
  import com.google.common.collect.ImmutableMap;
  
  public class CASQuery extends SchemaStatement
  {
      private final ImmutableList<Integer> keysIndex;
      private final ImmutableMap<Integer, Integer> casConditionArgFreqMap;
      private final String readQuery;
  
      private PreparedStatement casReadConditionStatement;
  
      public CASQuery(Timer timer, StressSettings settings, PartitionGenerator generator, SeedManager seedManager, PreparedStatement statement, ConsistencyLevel cl, ArgSelect argSelect, final String tableName)
      {
          super(timer, settings, new DataSpec(generator, seedManager, new DistributionFixed(1), settings.insert.rowPopulationRatio.get(), argSelect == SchemaStatement.ArgSelect.MULTIROW ? statement.getVariables().size() : 1), statement,
                statement.getVariables().asList().stream().map(ColumnDefinitions.Definition::getName).collect(Collectors.toList()), cl);
  
          if (argSelect != SchemaStatement.ArgSelect.SAMEROW)
              throw new IllegalArgumentException("CAS is supported only for type 'samerow'");
  
          ModificationStatement.Parsed modificationStatement;
          try
          {
              modificationStatement = CQLFragmentParser.parseAnyUnhandled(CqlParser::updateStatement,
                      statement.getQueryString());
          }
          catch (RecognitionException e)
          {
              throw new IllegalArgumentException("could not parse update query:" + statement.getQueryString(), e);
          }
  
          final List<ColumnCondition.Raw> casConditionList = modificationStatement.getConditions();
          List<Integer> casConditionIndex = new ArrayList<>();
  
          boolean first = true;
          StringBuilder casReadConditionQuery = new StringBuilder();
          casReadConditionQuery.append("SELECT ");
          for (final ColumnCondition.Raw condition : casConditionList)
          {
              if (!condition.containsBindMarkers())
              {
                  //condition uses static value, ignore it
                  continue;
              }
              if (!first)
              {
                  casReadConditionQuery.append(", ");
              }
              ColumnIdentifier column = condition.columnExpression().identifiers().get(0);
              casReadConditionQuery.append(column.toString());
              casConditionIndex.add(getDataSpecification().partitionGenerator.indexOf(column.toString()));
              first = false;
          }
          casReadConditionQuery.append(" FROM ").append(tableName).append(" WHERE ");
  
          first = true;
          ImmutableList.Builder<Integer> keysBuilder = ImmutableList.builder();
          for (final Generator key : getDataSpecification().partitionGenerator.getPartitionKey())
          {
              if (!first)
              {
                  casReadConditionQuery.append(" AND ");
              }
              casReadConditionQuery.append(key.name).append(" = ? ");
              keysBuilder.add(getDataSpecification().partitionGenerator.indexOf(key.name));
              first = false;
          }
          for (final Generator clusteringKey : getDataSpecification().partitionGenerator.getClusteringComponents())
          {
              casReadConditionQuery.append(" AND ").append(clusteringKey.name).append(" = ? ");
              keysBuilder.add(getDataSpecification().partitionGenerator.indexOf(clusteringKey.name));
          }
          keysIndex = keysBuilder.build();
          readQuery = casReadConditionQuery.toString();
  
          ImmutableMap.Builder<Integer, Integer> builder = ImmutableMap.builderWithExpectedSize(casConditionIndex.size());
          for (final Integer oneConditionIndex : casConditionIndex)
          {
              builder.put(oneConditionIndex, Math.toIntExact(Arrays.stream(argumentIndex).filter((x) -> x == oneConditionIndex).count()));
          }
          casConditionArgFreqMap = builder.build();
      }
  
      private class JavaDriverRun extends Runner
      {
          final JavaDriverClient client;
  
          private JavaDriverRun(JavaDriverClient client)
          {
              this.client = client;
              casReadConditionStatement = client.prepare(readQuery);
          }
  
          public boolean run()
          {
              ResultSet rs = client.getSession().execute(bind(client));
              rowCount = rs.all().size();
              partitionCount = Math.min(1, rowCount);
              return true;
          }
      }
  
      @Override
      public void run(JavaDriverClient client) throws IOException
      {
          timeWithRetry(new JavaDriverRun(client));
      }
  
      private BoundStatement bind(JavaDriverClient client)
      {
          final Object keys[] = new Object[keysIndex.size()];
          final Row row = getPartitions().get(0).next();
  
          for (int i = 0; i < keysIndex.size(); i++)
          {
              keys[i] = row.get(keysIndex.get(i));
          }
  
          //get current db values for all the coluns which are part of dynamic conditions
          ResultSet rs = client.getSession().execute(casReadConditionStatement.bind(keys));
          final Object casDbValues[] = new Object[casConditionArgFreqMap.size()];
  
          final com.datastax.driver.core.Row casDbValue = rs.one();
          if (casDbValue != null)
          {
              for (int i = 0; i < casConditionArgFreqMap.size(); i++)
              {
                  casDbValues[i] = casDbValue.getObject(i);
              }
          }
          //now bind db values for dynamic conditions in actual CAS update operation
          return prepare(row, casDbValues);
      }
  
      private BoundStatement prepare(final Row row, final Object[] casDbValues)
      {
          final Map<Integer, Integer> localMapping = new HashMap<>(casConditionArgFreqMap);
          int conditionIndexTracker = 0;
          for (int i = 0; i < argumentIndex.length; i++)
          {
              boolean replace = false;
              Integer count = localMapping.get(argumentIndex[i]);
              if (count != null)
              {
                  count--;
                  localMapping.put(argumentIndex[i], count);
                  if (count == 0)
                  {
                      replace = true;
                  }
              }
  
              if (replace)
              {
                  bindBuffer[i] = casDbValues[conditionIndexTracker++];
              }
              else
              {
                  Object value = row.get(argumentIndex[i]);
                  if (definitions.getType(i).getName() == DataType.date().getName())
                  {
                      // the java driver only accepts com.datastax.driver.core.LocalDate for CQL type "DATE"
                      value = LocalDate.fromDaysSinceEpoch((Integer) value);
                  }
  
                  bindBuffer[i] = value;
              }
  
              if (bindBuffer[i] == null && !getDataSpecification().partitionGenerator.permitNulls(argumentIndex[i]))
              {
                  throw new IllegalStateException();
              }
          }
          return statement.bind(bindBuffer);
      }
  }
  