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.kafka.image;
  
  import org.apache.kafka.common.errors.InvalidRequestException;
  import org.apache.kafka.common.errors.UnsupportedVersionException;
  import org.apache.kafka.common.message.DescribeClientQuotasRequestData;
  import org.apache.kafka.common.message.DescribeClientQuotasResponseData;
  import org.apache.kafka.common.message.DescribeClientQuotasResponseData.EntityData;
  import org.apache.kafka.common.message.DescribeClientQuotasResponseData.EntryData;
  import org.apache.kafka.common.quota.ClientQuotaEntity;
  import org.apache.kafka.image.node.ClientQuotasImageNode;
  import org.apache.kafka.image.writer.ImageWriter;
  import org.apache.kafka.image.writer.ImageWriterOptions;
  
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.Objects;
  import java.util.Set;
  
  import static org.apache.kafka.common.quota.ClientQuotaEntity.CLIENT_ID;
  import static org.apache.kafka.common.quota.ClientQuotaEntity.IP;
  import static org.apache.kafka.common.quota.ClientQuotaEntity.USER;
  import static org.apache.kafka.common.requests.DescribeClientQuotasRequest.MATCH_TYPE_DEFAULT;
  import static org.apache.kafka.common.requests.DescribeClientQuotasRequest.MATCH_TYPE_EXACT;
  import static org.apache.kafka.common.requests.DescribeClientQuotasRequest.MATCH_TYPE_SPECIFIED;
  
  
  /**
   * Represents the client quotas in the metadata image.
   *
   * This class is thread-safe.
   */
  public final class ClientQuotasImage {
      public static final ClientQuotasImage EMPTY = new ClientQuotasImage(Map.of());
  
      private final Map<ClientQuotaEntity, ClientQuotaImage> entities;
  
      public ClientQuotasImage(Map<ClientQuotaEntity, ClientQuotaImage> entities) {
          this.entities = Collections.unmodifiableMap(entities);
      }
  
      public boolean isEmpty() {
          return entities.isEmpty();
      }
  
      // Visible for testing
      public Map<ClientQuotaEntity, ClientQuotaImage> entities() {
          return entities;
      }
  
      public void write(ImageWriter writer, ImageWriterOptions options) {
          for (Entry<ClientQuotaEntity, ClientQuotaImage> entry : entities.entrySet()) {
              ClientQuotaEntity entity = entry.getKey();
              ClientQuotaImage clientQuotaImage = entry.getValue();
              clientQuotaImage.write(entity, writer, options);
          }
      }
  
      public DescribeClientQuotasResponseData describe(DescribeClientQuotasRequestData request) {
          DescribeClientQuotasResponseData response = new DescribeClientQuotasResponseData();
          Map<String, String> exactMatch = new HashMap<>();
          Set<String> typeMatch = new HashSet<>();
          for (DescribeClientQuotasRequestData.ComponentData component : request.components()) {
              if (component.entityType().isEmpty()) {
                  throw new InvalidRequestException("Invalid empty entity type.");
              } else if (exactMatch.containsKey(component.entityType()) ||
                      typeMatch.contains(component.entityType())) {
                  throw new InvalidRequestException("Entity type " + component.entityType() +
                      " cannot appear more than once in the filter.");
              }
              if (!(component.entityType().equals(IP) || component.entityType().equals(USER) ||
                      component.entityType().equals(CLIENT_ID))) {
                  throw new UnsupportedVersionException("Unsupported entity type " +
                          component.entityType());
              }
              switch (component.matchType()) {
                  case MATCH_TYPE_EXACT:
                      if (component.match() == null) {
                          throw new InvalidRequestException("Request specified " +
                              "MATCH_TYPE_EXACT, but set match string to null.");
                      }
                      exactMatch.put(component.entityType(), component.match());
                      break;
                  case MATCH_TYPE_DEFAULT:
                      if (component.match() != null) {
                          throw new InvalidRequestException("Request specified " +
                              "MATCH_TYPE_DEFAULT, but also specified a match string.");
                      }
                      exactMatch.put(component.entityType(), null);
                      break;
                  case MATCH_TYPE_SPECIFIED:
                      if (component.match() != null) {
                          throw new InvalidRequestException("Request specified " +
                              "MATCH_TYPE_SPECIFIED, but also specified a match string.");
                      }
                      typeMatch.add(component.entityType());
                      break;
                  default:
                      throw new InvalidRequestException("Unknown match type " + component.matchType());
              }
          }
          if (exactMatch.containsKey(IP) || typeMatch.contains(IP)) {
              if ((exactMatch.containsKey(USER) || typeMatch.contains(USER)) ||
                      (exactMatch.containsKey(CLIENT_ID) || typeMatch.contains(CLIENT_ID))) {
                  throw new InvalidRequestException("Invalid entity filter component " +
                      "combination. IP filter component should not be used with " +
                      "user or clientId filter component.");
              }
          }
          // TODO: this is O(N). We should add indexing here to speed it up. See KAFKA-13022.
          for (Entry<ClientQuotaEntity, ClientQuotaImage> entry : entities.entrySet()) {
              ClientQuotaEntity entity = entry.getKey();
              ClientQuotaImage quotaImage = entry.getValue();
              if (matches(entity, exactMatch, typeMatch, request.strict())) {
                  response.entries().add(toDescribeEntry(entity, quotaImage));
              }
          }
          return response;
      }
  
      private static boolean matches(ClientQuotaEntity entity,
                                     Map<String, String> exactMatch,
                                     Set<String> typeMatch,
                                     boolean strict) {
          if (strict) {
              if (entity.entries().size() != exactMatch.size() + typeMatch.size()) {
                  return false;
              }
          }
          for (Entry<String, String> entry : exactMatch.entrySet()) {
              if (!entity.entries().containsKey(entry.getKey())) {
                  return false;
              }
              if (!Objects.equals(entity.entries().get(entry.getKey()), entry.getValue())) {
                  return false;
              }
          }
          for (String type : typeMatch) {
              if (!entity.entries().containsKey(type)) {
                  return false;
              }
          }
          return true;
      }
  
      private static EntryData toDescribeEntry(ClientQuotaEntity entity,
                                               ClientQuotaImage quotaImage) {
          EntryData data = new EntryData();
          for (Entry<String, String> entry : entity.entries().entrySet()) {
              data.entity().add(new EntityData().
                  setEntityType(entry.getKey()).
                  setEntityName(entry.getValue()));
          }
          data.setValues(quotaImage.toDescribeValues());
          return data;
      }
  
      @Override
      public boolean equals(Object o) {
          if (!(o instanceof ClientQuotasImage other)) return false;
          return entities.equals(other.entities);
      }
  
      @Override
      public int hashCode() {
          return Objects.hash(entities);
      }
  
      @Override
      public String toString() {
          return new ClientQuotasImageNode(this).stringify();
      }
  }
  