/*
 * 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.flink.streaming.runtime.streamrecord;

import org.apache.flink.annotation.PublicEvolving;

/**
 * Special record type carrying a timestamp of its creation time at a source operator
 * and the vertexId and subtask index of the operator.
 *
 * <p>At sinks, the marker can be used to approximate the time a record needs to travel
 * through the dataflow.
 */
@PublicEvolving
public final class LatencyMarker extends StreamElement {

	// ------------------------------------------------------------------------

	/** The time the latency mark is denoting. */
	private final long markedTime;

	private final int vertexID;

	private final int subtaskIndex;

	/**
	 * Creates a latency mark with the given timestamp.
	 */
	public LatencyMarker(long markedTime, int vertexID, int subtaskIndex) {
		this.markedTime = markedTime;
		this.vertexID = vertexID;
		this.subtaskIndex = subtaskIndex;
	}

	/**
	 * Returns the timestamp marked by the LatencyMarker.
	 */
	public long getMarkedTime() {
		return markedTime;
	}

	public int getVertexID() {
		return vertexID;
	}

	public int getSubtaskIndex() {
		return subtaskIndex;
	}

	// ------------------------------------------------------------------------


	@Override
	public boolean equals(Object o) {
		if (this == o) {
			return true;
		}
		if (o == null || getClass() != o.getClass()){
			return false;
		}

		LatencyMarker that = (LatencyMarker) o;

		if (markedTime != that.markedTime) {
			return false;
		}
		if (vertexID != that.vertexID) {
			return false;
		}
		return subtaskIndex == that.subtaskIndex;

	}

	@Override
	public int hashCode() {
		int result = (int) (markedTime ^ (markedTime >>> 32));
		result = 31 * result + vertexID;
		result = 31 * result + subtaskIndex;
		return result;
	}

	@Override
	public String toString() {
		return "LatencyMarker{" +
				"markedTime=" + markedTime +
				", vertexID=" + vertexID +
				", subtaskIndex=" + subtaskIndex +
				'}';
	}
}