/*
 * 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.connectors.kinesis.model;

import org.junit.Test;

import static org.apache.flink.streaming.connectors.kinesis.model.DynamoDBStreamsShardHandle.SHARDID_PREFIX;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

/**
 * Shard handle unit tests.
 */
public class DynamoDBStreamsShardHandleTest {
	@Test
	public void testIsValidShardId() {
		// normal form
		String shardId = "shardId-00000001536805703746-69688cb1";
		assertEquals(true, DynamoDBStreamsShardHandle.isValidShardId(shardId));

		// short form
		shardId = "shardId-00000001536805703746";
		assertEquals(true, DynamoDBStreamsShardHandle.isValidShardId(shardId));

		// long form
		shardId = "shardId-00000001536805703746-69688cb1aljkwerijfl8228sl12a123akfla";
		assertEquals(true, DynamoDBStreamsShardHandle.isValidShardId(shardId));

		// invalid with wrong prefix
		shardId = "sId-00000001536805703746-69688cb1";
		assertEquals(false, DynamoDBStreamsShardHandle.isValidShardId(shardId));

		// invalid with non-digits
		shardId = "shardId-0000000153680570aabb-69688cb1";
		assertEquals(false, DynamoDBStreamsShardHandle.isValidShardId(shardId));

		// invalid with shardId too long
		shardId = "shardId-00000001536805703746-69688cb1aljkwerijfl8228sl12a123akfla0000";
		assertEquals(false, DynamoDBStreamsShardHandle.isValidShardId(shardId));
	}

	@Test
	public void testCompareShardId() {
		final int numShardIds = 10;
		final int shardIdDigitLen = 20;
		final String zeros = "00000000000000000000";  // twenty '0' chars
		String shardIdValid = "shardId-00000001536805703746-69688cb1";
		String shardIdInvalid = "shardId-0000000153680570aabb-69688cb1";

		assertEquals(0, DynamoDBStreamsShardHandle.compareShardIds(shardIdValid, shardIdValid));

		// comparison of invalid shardIds should yield exception
		try {
			DynamoDBStreamsShardHandle.compareShardIds(shardIdValid, shardIdInvalid);
			fail("invalid shard Id" + shardIdInvalid + " should trigger exception");
		} catch (IllegalArgumentException e) {
			// expected
		}
		try {
			DynamoDBStreamsShardHandle.compareShardIds(shardIdInvalid, shardIdValid);
			fail("invalid shard Id" + shardIdInvalid + " should trigger exception");
		} catch (IllegalArgumentException e) {
			// expected
		}

		// compare randomly generated shardIds based on timestamp
		String[] shardIds = new String[numShardIds];
		for (int i = 0; i < numShardIds; i++) {
			String nowStr = String.valueOf(System.currentTimeMillis());
			if (nowStr.length() < shardIdDigitLen) {
				shardIds[i] = SHARDID_PREFIX + zeros.substring(0, shardIdDigitLen - nowStr.length())
						+ nowStr;
			} else {
				shardIds[i] = SHARDID_PREFIX + nowStr.substring(0, shardIdDigitLen);
			}
			try {
				Thread.sleep(100);
			} catch (InterruptedException e) {
				// ignore
			}
		}
		for (int i = 1; i < numShardIds - 1; i++) {
			assertTrue(DynamoDBStreamsShardHandle.compareShardIds(shardIds[i - 1], shardIds[i]) < 0);
			assertTrue(DynamoDBStreamsShardHandle.compareShardIds(shardIds[i], shardIds[i]) == 0);
			assertTrue(DynamoDBStreamsShardHandle.compareShardIds(shardIds[i], shardIds[i + 1]) < 0);
		}
	}

}