/*
 * 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.util;

import org.apache.flink.core.testutils.CommonTestUtils;

import org.junit.Test;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

/**
 * This class contains tests for the {@link org.apache.flink.util.AbstractID} class.
 */
public class AbstractIDTest extends TestLogger {

	/**
	 * Tests the serialization/deserialization of an abstract ID.
	 */
	@Test
	public void testSerialization() throws Exception {
		final AbstractID origID = new AbstractID();
		final AbstractID copyID = CommonTestUtils.createCopySerializable(origID);

		assertEquals(origID.hashCode(), copyID.hashCode());
		assertEquals(origID, copyID);
	}

	@Test
	public void testConvertToBytes() throws Exception {
		final AbstractID origID = new AbstractID();

		AbstractID copy1 = new AbstractID(origID);
		AbstractID copy2 = new AbstractID(origID.getBytes());
		AbstractID copy3 = new AbstractID(origID.getLowerPart(), origID.getUpperPart());

		assertEquals(origID, copy1);
		assertEquals(origID, copy2);
		assertEquals(origID, copy3);
	}

	@Test
	public void testCompare() throws Exception {
		AbstractID id1 = new AbstractID(0, 0);
		AbstractID id2 = new AbstractID(1, 0);
		AbstractID id3 = new AbstractID(0, 1);
		AbstractID id4 = new AbstractID(-1, 0);
		AbstractID id5 = new AbstractID(0, -1);
		AbstractID id6 = new AbstractID(-1, -1);

		AbstractID id7 = new AbstractID(Long.MAX_VALUE, Long.MAX_VALUE);
		AbstractID id8 = new AbstractID(Long.MIN_VALUE, Long.MIN_VALUE);
		AbstractID id9 = new AbstractID(Long.MAX_VALUE, Long.MIN_VALUE);
		AbstractID id10 = new AbstractID(Long.MIN_VALUE, Long.MAX_VALUE);

		// test self equality
		assertEquals(0, id1.compareTo(CommonTestUtils.createCopySerializable(id1)));
		assertEquals(0, id2.compareTo(CommonTestUtils.createCopySerializable(id2)));
		assertEquals(0, id3.compareTo(CommonTestUtils.createCopySerializable(id3)));
		assertEquals(0, id4.compareTo(CommonTestUtils.createCopySerializable(id4)));
		assertEquals(0, id5.compareTo(CommonTestUtils.createCopySerializable(id5)));
		assertEquals(0, id6.compareTo(CommonTestUtils.createCopySerializable(id6)));
		assertEquals(0, id7.compareTo(CommonTestUtils.createCopySerializable(id7)));
		assertEquals(0, id8.compareTo(CommonTestUtils.createCopySerializable(id8)));
		assertEquals(0, id9.compareTo(CommonTestUtils.createCopySerializable(id9)));
		assertEquals(0, id10.compareTo(CommonTestUtils.createCopySerializable(id10)));

		// test order
		assertCompare(id1, id2, -1);
		assertCompare(id1, id3, -1);
		assertCompare(id1, id4, 1);
		assertCompare(id1, id5, 1);
		assertCompare(id1, id6, 1);
		assertCompare(id2, id5, 1);
		assertCompare(id3, id5, 1);
		assertCompare(id2, id6, 1);
		assertCompare(id3, id6, 1);
		assertCompare(id1, id7, -1);
		assertCompare(id1, id8, 1);
		assertCompare(id7, id8, 1);
		assertCompare(id9, id10, -1);
		assertCompare(id7, id9, 1);
		assertCompare(id7, id10, 1);
		assertCompare(id8, id9, -1);
		assertCompare(id8, id10, -1);
	}

	private static void assertCompare(AbstractID a, AbstractID b, int signum) {
		int cmpAB = a.compareTo(b);
		int cmpBA = b.compareTo(a);

		int sgnAB = cmpAB > 0 ? 1 : (cmpAB < 0 ? -1 : 0);
		int sgnBA = cmpBA > 0 ? 1 : (cmpBA < 0 ? -1 : 0);

		assertEquals(signum, sgnAB);
		assertTrue(sgnAB == -sgnBA);
	}
}