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.streams.processor.internals.assignment;
  
  import org.apache.kafka.streams.processor.assignment.KafkaStreamsState;
  import org.apache.kafka.streams.processor.assignment.ProcessId;
  
  import org.junit.jupiter.api.Test;
  
  import java.util.Arrays;
  import java.util.Optional;
  import java.util.Set;
  import java.util.TreeMap;
  import java.util.TreeSet;
  
  import static org.apache.kafka.common.utils.Utils.mkEntry;
  import static org.apache.kafka.common.utils.Utils.mkMap;
  import static org.apache.kafka.common.utils.Utils.mkSortedSet;
  import static org.apache.kafka.streams.processor.internals.assignment.AssignmentTestUtils.NAMED_TASK_T0_0_0;
  import static org.apache.kafka.streams.processor.internals.assignment.AssignmentTestUtils.NAMED_TASK_T0_0_1;
  import static org.apache.kafka.streams.processor.internals.assignment.AssignmentTestUtils.NAMED_TASK_T0_1_0;
  import static org.hamcrest.CoreMatchers.equalTo;
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  public class KafkaStreamsStateTest {
      @Test
      public void shouldCorrectlyReturnTasksByLag() {
          final KafkaStreamsState state = new DefaultKafkaStreamsState(
              ProcessId.randomProcessId(),
              10,
              mkMap(),
              mkSortedSet(NAMED_TASK_T0_0_0, NAMED_TASK_T0_0_1),
              mkSortedSet(),
              new TreeMap<>(mkMap(
                  mkEntry("c1", Set.of(NAMED_TASK_T0_0_0, NAMED_TASK_T0_0_1))
              )),
              Optional.empty(),
              Optional.of(
                  mkMap(
                      mkEntry(NAMED_TASK_T0_0_0, 2000L),
                      mkEntry(NAMED_TASK_T0_0_1, 1000L)
                  )
              ),
              Optional.empty()
          );
  
          assertThrows(IllegalStateException.class, () -> state.lagFor(NAMED_TASK_T0_1_0));
          assertThat(state.lagFor(NAMED_TASK_T0_0_0), equalTo(2000L));
          assertThat(state.lagFor(NAMED_TASK_T0_0_1), equalTo(1000L));
  
          assertThat(state.prevTasksByLag("c0"), equalTo(new TreeSet<>()));
          assertThat(state.prevTasksByLag("c1"), equalTo(new TreeSet<>(
              Arrays.asList(NAMED_TASK_T0_0_1, NAMED_TASK_T0_0_0)
          )));
      }
  
      @Test
      public void shouldThrowExceptionOnLagOperationsIfLagsWereNotComputed() {
          final KafkaStreamsState state = new DefaultKafkaStreamsState(
              ProcessId.randomProcessId(),
              10,
              mkMap(),
              mkSortedSet(NAMED_TASK_T0_0_0, NAMED_TASK_T0_0_1),
              mkSortedSet(),
              new TreeMap<>(mkMap(
                  mkEntry("c1", Set.of(NAMED_TASK_T0_0_0, NAMED_TASK_T0_0_1))
              )),
              Optional.empty(),
              Optional.empty(),
              Optional.empty()
          );
  
          assertThrows(UnsupportedOperationException.class, () -> state.lagFor(NAMED_TASK_T0_0_0));
          assertThrows(UnsupportedOperationException.class, () -> state.prevTasksByLag("c1"));
          assertThrows(UnsupportedOperationException.class, state::statefulTasksToLagSums);
      }
  }
  