/*
 * 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.sdk.fn.data;

import com.google.auto.value.AutoValue;
import javax.annotation.Nullable;
import org.apache.beam.model.fnexecution.v1.BeamFnApi;

/**
 * A logical endpoint is a pair of an instruction ID corresponding to the {@link
 * BeamFnApi.ProcessBundleRequest} and the transform within the processing graph. This enables the
 * same Data Service or Data Client to be re-used across multiple bundles.
 */
@AutoValue
public abstract class LogicalEndpoint {

  public abstract String getInstructionId();

  public abstract String getTransformId();

  @Nullable
  public abstract String getTimerFamilyId();

  public boolean isTimer() {
    return getTimerFamilyId() != null;
  }

  public static LogicalEndpoint data(String instructionId, String transformId) {
    return new AutoValue_LogicalEndpoint(instructionId, transformId, null);
  }

  public static LogicalEndpoint timer(
      String instructionId, String transformId, String timerFamilyId) {
    if (timerFamilyId == null) {
      throw new NullPointerException("timerFamilyId");
    }
    return new AutoValue_LogicalEndpoint(instructionId, transformId, timerFamilyId);
  }
}
