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 org.apache.cassandra.index.sai.analyzer;
  
  import java.nio.ByteBuffer;
  import java.util.Map;
  
  import com.google.common.base.MoreObjects;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import org.apache.cassandra.index.sai.analyzer.filter.BasicFilters;
  import org.apache.cassandra.index.sai.analyzer.filter.FilterPipeline;
  import org.apache.cassandra.index.sai.analyzer.filter.FilterPipelineExecutor;
  import org.apache.cassandra.index.sai.utils.IndexTermType;
  import org.apache.cassandra.serializers.MarshalException;
  import org.apache.cassandra.utils.ByteBufferUtil;
  
  /**
   * Analyzer that does *not* tokenize the input. Optionally will
   * apply filters for the input based on {@link NonTokenizingOptions}.
   */
  public class NonTokenizingAnalyzer extends AbstractAnalyzer
  {
      private static final Logger logger = LoggerFactory.getLogger(NonTokenizingAnalyzer.class);
  
      private final IndexTermType indexTermType;
      private final NonTokenizingOptions options;
      private final FilterPipeline filterPipeline;
  
      private ByteBuffer input;
      private boolean hasNext = false;
  
      NonTokenizingAnalyzer(IndexTermType indexTermType, Map<String, String> options)
      {
          this(indexTermType, NonTokenizingOptions.fromMap(options));
      }
  
      NonTokenizingAnalyzer(IndexTermType indexTermType, NonTokenizingOptions tokenizerOptions)
      {
          this.indexTermType = indexTermType;
          this.options = tokenizerOptions;
          this.filterPipeline = getFilterPipeline();
      }
  
      @Override
      public boolean hasNext()
      {
          // check that we know how to handle the input, otherwise bail
          if (!indexTermType.isString())
              return false;
  
          if (hasNext)
          {
              try
              {
                  String input = indexTermType.asString(this.input);
  
                  if (input == null)
                  {
                      throw new MarshalException(String.format("'null' deserialized value for %s with %s",
                                                               ByteBufferUtil.bytesToHex(this.input), indexTermType));
                  }
  
                  String result = FilterPipelineExecutor.execute(filterPipeline, input);
                  
                  if (result == null)
                  {
                      nextLiteral = null;
                      next = null;
                      return false;
                  }
  
                  nextLiteral = result;
                  next = indexTermType.fromString(result);
  
                  return true;
              }
              catch (MarshalException e)
              {
                  logger.error("Failed to deserialize value with " + indexTermType, e);
                  return false;
              }
              finally
              {
                  hasNext = false;
              }
          }
  
          return false;
      }
  
      @Override
      public boolean transformValue()
      {
          return !options.isCaseSensitive() || options.isNormalized() || options.isAscii();
      }
  
      @Override
      protected void resetInternal(ByteBuffer input)
      {
          this.input = input;
          this.hasNext = true;
      }
  
      private FilterPipeline getFilterPipeline()
      {
          FilterPipeline builder = new FilterPipeline(new BasicFilters.NoOperation());
          
          if (!options.isCaseSensitive())
              builder = builder.add("to_lower", new BasicFilters.LowerCase());
          
          if (options.isNormalized())
              builder = builder.add("normalize", new BasicFilters.Normalize());
  
          if (options.isAscii())
              builder = builder.add("ascii", new BasicFilters.Ascii());
          
          return builder;
      }
  
      @Override
      public String toString()
      {
          return MoreObjects.toStringHelper(this)
                            .add("caseSensitive", options.isCaseSensitive())
                            .add("normalized", options.isNormalized())
                            .add("ascii", options.isAscii())
                            .toString();
      }
  }
  