content: /*
   * Copyright 2021-2024 Aklivity Inc.
   *
   * Aklivity 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 io.aklivity.zilla.runtime.binding.kafka.internal.cache;
  
  import java.nio.file.Path;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.concurrent.atomic.AtomicLong;
  
  import org.agrona.BitUtil;
  
  import io.aklivity.zilla.runtime.binding.kafka.internal.KafkaConfiguration;
  
  public final class KafkaCache
  {
      private final AtomicLong produceCapacity = new AtomicLong(0L);
  
      private static final long[] EMPTY_SORT_SPACE = new long[0];
  
      private final KafkaConfiguration config;
      private final String name;
      private final Path location;
      private final Map<String, KafkaCacheTopic> topicsByName;
      private final ThreadLocal<long[]> sortSpaceRef;
  
      public KafkaCache(
          KafkaConfiguration config,
          String name)
      {
          this.config = config;
          this.name = name;
          this.location = config.cacheDirectory().resolve(name);
          this.topicsByName = new ConcurrentHashMap<>();
          this.sortSpaceRef = ThreadLocal.withInitial(() -> EMPTY_SORT_SPACE);
      }
  
      public boolean hasAvailableProduceCapacity()
      {
          return produceCapacity.longValue() < config.cacheProduceCapacity();
      }
  
      public String name()
      {
          return name;
      }
  
      public KafkaCacheTopic supplyTopic(
          String name)
      {
          return topicsByName.computeIfAbsent(name, this::newTopic);
      }
  
      @Override
      public String toString()
      {
          return String.format("[%s] %s", getClass().getSimpleName(), name);
      }
  
      private KafkaCacheTopic newTopic(
          String topic)
      {
          return new KafkaCacheTopic(location, config, name, produceCapacity, topic, this::supplySortSpace);
      }
  
      private long[] supplySortSpace(
          int lengthMin)
      {
          long[] sortSpace = sortSpaceRef.get();
  
          if (sortSpace.length < lengthMin)
          {
              sortSpace = new long[BitUtil.findNextPositivePowerOfTwo(lengthMin)];
              sortSpaceRef.set(sortSpace);
          }
  
          return sortSpace;
      }
  }
  