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.cql;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.List;
  
  import io.github.jbellis.jvector.graph.GraphIndexBuilder;
  import io.github.jbellis.jvector.graph.GraphSearcher;
  import io.github.jbellis.jvector.vector.VectorEncoding;
  import io.github.jbellis.jvector.vector.VectorSimilarityFunction;
  import org.apache.cassandra.index.sai.SAITester;
  import org.apache.cassandra.index.sai.disk.v1.vector.ConcurrentVectorValues;
  import org.apache.cassandra.index.sai.utils.Glove;
  import org.apache.cassandra.inject.ActionBuilder;
  import org.apache.cassandra.inject.Injections;
  import org.apache.cassandra.inject.InvokePointBuilder;
  import org.junit.Before;
  import org.junit.BeforeClass;
  
  public class VectorTester extends SAITester
  {
      protected static Glove.WordVector word2vec;
  
      @BeforeClass
      public static void loadModel() throws Throwable
      {
          word2vec = Glove.parse(VectorTester.class.getClassLoader().getResourceAsStream("glove.3K.50d.txt"));
      }
  
      @Before
      public void setup() throws Throwable
      {
          // override maxBruteForceRows to a random number between 0 and 4 so that we make sure
          // the non-brute-force path gets called during tests (which mostly involve small numbers of rows)
          var n = getRandom().nextIntBetween(0, 4);
          var limitToTopResults = InvokePointBuilder.newInvokePoint()
                                                    .onClass("org.apache.cassandra.index.sai.disk.v2.V2VectorIndexSearcher")
                                                    .onMethod("limitToTopResults")
                                                    .atEntry();
          var bitsOrPostingListForKeyRange = InvokePointBuilder.newInvokePoint()
                                                               .onClass("org.apache.cassandra.index.sai.disk.v2.V2VectorIndexSearcher")
                                                               .onMethod("bitsOrPostingListForKeyRange")
                                                               .atEntry();
          var ab = ActionBuilder.newActionBuilder()
                                .actions()
                                .doAction("$this.globalBruteForceRows = " + n);
          var changeBruteForceThreshold = Injections.newCustom("force_non_bruteforce_queries")
                                                    .add(limitToTopResults)
                                                    .add(bitsOrPostingListForKeyRange)
                                                    .add(ab)
                                                    .build();
          Injections.inject(changeBruteForceThreshold);
      }
  
      public static double rawIndexedRecall(Collection<float[]> vectors, float[] query, List<float[]> result, int topK) throws IOException
      {
          ConcurrentVectorValues vectorValues = new ConcurrentVectorValues(query.length);
          int ordinal = 0;
  
          var graphBuilder = new GraphIndexBuilder<>(vectorValues,
                                                     VectorEncoding.FLOAT32,
                                                     VectorSimilarityFunction.COSINE,
                                                     16,
                                                     100,
                                                     1.2f,
                                                     1.4f);
  
          for (float[] vector : vectors)
          {
              vectorValues.add(ordinal, vector);
              graphBuilder.addGraphNode(ordinal++, vectorValues);
          }
  
          var results = GraphSearcher.search(query,
                                             topK,
                                             vectorValues,
                                             VectorEncoding.FLOAT32,
                                             VectorSimilarityFunction.COSINE,
                                             graphBuilder.getGraph(),
                                             null);
  
          List<float[]> nearestNeighbors = new ArrayList<>();
          for (var ns : results.getNodes())
              nearestNeighbors.add(vectorValues.vectorValue(ns.node));
  
          return recallMatch(nearestNeighbors, result, topK);
      }
  
      public static double recallMatch(List<float[]> expected, List<float[]> actual, int topK)
      {
          if (expected.isEmpty() && actual.isEmpty())
              return 1.0;
  
          int matches = 0;
          for (float[] in : expected)
          {
              for (float[] out : actual)
              {
                  if (Arrays.compare(in, out) == 0)
                  {
                      matches++;
                      break;
                  }
              }
          }
  
          return (double) matches / topK;
      }
  }
  