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.common.requests;
  
  import org.apache.kafka.common.acl.AccessControlEntry;
  import org.apache.kafka.common.acl.AclBinding;
  import org.apache.kafka.common.acl.AclOperation;
  import org.apache.kafka.common.acl.AclPermissionType;
  import org.apache.kafka.common.errors.UnsupportedVersionException;
  import org.apache.kafka.common.message.DescribeAclsResponseData;
  import org.apache.kafka.common.message.DescribeAclsResponseData.AclDescription;
  import org.apache.kafka.common.message.DescribeAclsResponseData.DescribeAclsResource;
  import org.apache.kafka.common.protocol.ApiKeys;
  import org.apache.kafka.common.protocol.Errors;
  import org.apache.kafka.common.protocol.Readable;
  import org.apache.kafka.common.resource.PatternType;
  import org.apache.kafka.common.resource.ResourcePattern;
  import org.apache.kafka.common.resource.ResourceType;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.Optional;
  import java.util.Set;
  import java.util.stream.Collectors;
  import java.util.stream.Stream;
  
  public class DescribeAclsResponse extends AbstractResponse {
  
      private final DescribeAclsResponseData data;
  
      public DescribeAclsResponse(DescribeAclsResponseData data, short version) {
          super(ApiKeys.DESCRIBE_ACLS);
          this.data = data;
          validate(Optional.of(version));
      }
  
      // Skips version validation, visible for testing
      DescribeAclsResponse(DescribeAclsResponseData data) {
          super(ApiKeys.DESCRIBE_ACLS);
          this.data = data;
          validate(Optional.empty());
      }
  
      @Override
      public DescribeAclsResponseData data() {
          return data;
      }
  
      @Override
      public int throttleTimeMs() {
          return data.throttleTimeMs();
      }
  
      @Override
      public void maybeSetThrottleTimeMs(int throttleTimeMs) {
          data.setThrottleTimeMs(throttleTimeMs);
      }
  
      public ApiError error() {
          return new ApiError(Errors.forCode(data.errorCode()), data.errorMessage());
      }
  
      @Override
      public Map<Errors, Integer> errorCounts() {
          return errorCounts(Errors.forCode(data.errorCode()));
      }
  
      public final List<DescribeAclsResource> acls() {
          return data.resources();
      }
  
      public static DescribeAclsResponse parse(Readable readable, short version) {
          return new DescribeAclsResponse(new DescribeAclsResponseData(readable, version), version);
      }
  
      @Override
      public boolean shouldClientThrottle(short version) {
          return version >= 1;
      }
  
      private void validate(Optional<Short> version) {
          if (version.isPresent() && version.get() == 0) {
              final boolean unsupported = acls().stream()
                  .anyMatch(acl -> acl.patternType() != PatternType.LITERAL.code());
              if (unsupported) {
                  throw new UnsupportedVersionException("Version 0 only supports literal resource pattern types");
              }
          }
  
          for (DescribeAclsResource resource : acls()) {
              if (resource.patternType() == PatternType.UNKNOWN.code() || resource.resourceType() == ResourceType.UNKNOWN.code())
                  throw new IllegalArgumentException("Contain UNKNOWN elements");
              for (AclDescription acl : resource.acls()) {
                  if (acl.operation() == AclOperation.UNKNOWN.code() || acl.permissionType() == AclPermissionType.UNKNOWN.code()) {
                      throw new IllegalArgumentException("Contain UNKNOWN elements");
                  }
              }
          }
      }
  
      private static Stream<AclBinding> aclBindings(DescribeAclsResource resource) {
          return resource.acls().stream().map(acl -> {
              ResourcePattern pattern = new ResourcePattern(
                      ResourceType.fromCode(resource.resourceType()),
                      resource.resourceName(),
                      PatternType.fromCode(resource.patternType()));
              AccessControlEntry entry = new AccessControlEntry(
                      acl.principal(),
                      acl.host(),
                      AclOperation.fromCode(acl.operation()),
                      AclPermissionType.fromCode(acl.permissionType()));
              return new AclBinding(pattern, entry);
          });
      }
  
      public static List<AclBinding> aclBindings(List<DescribeAclsResource> resources) {
          return resources.stream().flatMap(DescribeAclsResponse::aclBindings).collect(Collectors.toList());
      }
  
      public static List<DescribeAclsResource> aclsResources(Iterable<AclBinding> acls) {
          Map<ResourcePattern, Set<AccessControlEntry>> patternToEntries = new HashMap<>();
          for (AclBinding acl : acls) {
              patternToEntries.computeIfAbsent(acl.pattern(), v -> new HashSet<>()).add(acl.entry());
          }
          List<DescribeAclsResource> resources = new ArrayList<>(patternToEntries.size());
          for (Entry<ResourcePattern, Set<AccessControlEntry>> entry : patternToEntries.entrySet()) {
              ResourcePattern key = entry.getKey();
              List<AclDescription> aclDescriptions = new ArrayList<>(entry.getValue().size());
              for (AccessControlEntry ace : entry.getValue()) {
                  AclDescription ad = new AclDescription()
                      .setHost(ace.host())
                      .setOperation(ace.operation().code())
                      .setPermissionType(ace.permissionType().code())
                      .setPrincipal(ace.principal());
                  aclDescriptions.add(ad);
              }
              DescribeAclsResource dar = new DescribeAclsResource()
                  .setResourceName(key.name())
                  .setPatternType(key.patternType().code())
                  .setResourceType(key.resourceType().code())
                  .setAcls(aclDescriptions);
              resources.add(dar);
          }
          return resources;
      }
  }
  