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.beam.runners.core.triggers;
  
  import static org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.base.Preconditions.checkArgument;
  
  import java.util.Arrays;
  import java.util.List;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.base.Joiner;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.ImmutableList;
  
  /**
   * A {@link TriggerStateMachine} that fires and finishes once after all of its sub-triggers have
   * fired.
   */
  @SuppressWarnings({
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class AfterAllStateMachine extends TriggerStateMachine {
  
    private AfterAllStateMachine(List<TriggerStateMachine> subTriggers) {
      super(subTriggers);
      checkArgument(subTriggers.size() > 1);
    }
  
    /** Returns an {@code AfterAll} {@code Trigger} with the given subtriggers. */
    @SafeVarargs
    public static TriggerStateMachine of(TriggerStateMachine... triggers) {
      return new AfterAllStateMachine(Arrays.asList(triggers));
    }
  
    public static TriggerStateMachine of(Iterable<? extends TriggerStateMachine> triggers) {
      return new AfterAllStateMachine(ImmutableList.copyOf(triggers));
    }
  
    @Override
    public void prefetchOnElement(PrefetchContext c) {
      for (ExecutableTriggerStateMachine subTrigger : c.trigger().subTriggers()) {
        subTrigger.invokePrefetchOnElement(c.forTrigger(subTrigger));
      }
    }
  
    @Override
    public void onElement(OnElementContext c) throws Exception {
      for (ExecutableTriggerStateMachine subTrigger : c.trigger().unfinishedSubTriggers()) {
        // Since subTriggers are all OnceTriggers, they must either CONTINUE or FIRE_AND_FINISH.
        // invokeElement will automatically mark the finish bit if they return FIRE_AND_FINISH.
        subTrigger.invokeOnElement(c);
      }
    }
  
    @Override
    public void prefetchOnMerge(MergingPrefetchContext c) {
      for (ExecutableTriggerStateMachine subTrigger : c.trigger().subTriggers()) {
        subTrigger.invokePrefetchOnMerge(c.forTrigger(subTrigger));
      }
    }
  
    @Override
    public void onMerge(OnMergeContext c) throws Exception {
      for (ExecutableTriggerStateMachine subTrigger : c.trigger().subTriggers()) {
        subTrigger.invokeOnMerge(c);
      }
      boolean allFinished = true;
      for (ExecutableTriggerStateMachine subTrigger1 : c.trigger().subTriggers()) {
        allFinished &= c.forTrigger(subTrigger1).trigger().isFinished();
      }
      c.trigger().setFinished(allFinished);
    }
  
    @Override
    public void prefetchShouldFire(PrefetchContext c) {
      for (ExecutableTriggerStateMachine subTrigger : c.trigger().subTriggers()) {
        subTrigger.invokePrefetchShouldFire(c.forTrigger(subTrigger));
      }
    }
  
    /**
     * {@inheritDoc}
     *
     * @return {@code true} if all subtriggers return {@code true}.
     */
    @Override
    public boolean shouldFire(TriggerContext context) throws Exception {
      for (ExecutableTriggerStateMachine subTrigger : context.trigger().subTriggers()) {
        if (!context.forTrigger(subTrigger).trigger().isFinished()
            && !subTrigger.invokeShouldFire(context)) {
          return false;
        }
      }
      return true;
    }
  
    @Override
    public void onFire(TriggerContext context) throws Exception {
      for (ExecutableTriggerStateMachine subTrigger : context.trigger().subTriggers()) {
        subTrigger.invokeOnFire(context);
      }
      context.trigger().setFinished(true);
    }
  
    @Override
    public String toString() {
      StringBuilder builder = new StringBuilder("AfterAll.of(");
      Joiner.on(", ").appendTo(builder, subTriggers);
      builder.append(")");
      return builder.toString();
    }
  }
  