/*
 * 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.runtime.io.network.buffer;

import org.apache.flink.core.memory.MemorySegment;
import org.apache.flink.core.memory.MemorySegmentFactory;
import org.junit.Assert;
import org.junit.Test;
import org.mockito.Mockito;

import java.nio.ByteBuffer;

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

public class BufferTest {

	@Test
	public void testSetGetSize() {
		final MemorySegment segment = MemorySegmentFactory.allocateUnpooledSegment(1024);
		final BufferRecycler recycler = Mockito.mock(BufferRecycler.class);

		Buffer buffer = new Buffer(segment, recycler);
		Assert.assertEquals(segment.size(), buffer.getSize());

		buffer.setSize(segment.size() / 2);
		Assert.assertEquals(segment.size() / 2, buffer.getSize());

		try {
			buffer.setSize(-1);
			Assert.fail("Didn't throw expected exception");
		} catch (IllegalArgumentException e) {
			// OK => expected exception
		}

		try {
			buffer.setSize(segment.size() + 1);
			Assert.fail("Didn't throw expected exception");
		} catch (IllegalArgumentException e) {
			// OK => expected exception
		}
	}

	@Test
	public void testgetNioBufferThreadSafe() {
		final MemorySegment segment = MemorySegmentFactory.allocateUnpooledSegment(1024);
		final BufferRecycler recycler = Mockito.mock(BufferRecycler.class);

		Buffer buffer = new Buffer(segment, recycler);

		ByteBuffer buf1 = buffer.getNioBuffer();
		ByteBuffer buf2 = buffer.getNioBuffer();

		assertNotNull(buf1);
		assertNotNull(buf2);

		assertTrue("Repeated call to getNioBuffer() returns the same nio buffer", buf1 != buf2);
	}
}