/*
 * 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.logging.log4j.core.appender.mom.kafka;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.ObjectInput;
import java.nio.charset.StandardCharsets;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

import org.apache.kafka.clients.producer.MockProducer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.clients.producer.RecordMetadata;
import org.apache.log4j.MDC;
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.categories.Appenders;
import org.apache.logging.log4j.core.Appender;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.impl.Log4jLogEvent;
import org.apache.logging.log4j.junit.LoggerContextRule;
import org.apache.logging.log4j.message.SimpleMessage;
import org.apache.logging.log4j.util.FilteredObjectInputStream;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Rule;
import org.junit.Test;
import org.junit.experimental.categories.Category;

@Category(Appenders.Kafka.class)
public class KafkaAppenderTest {

	private static final MockProducer<byte[], byte[]> kafka = new MockProducer<byte[], byte[]>(true, null, null) {

		@Override
		public synchronized Future<RecordMetadata> send(ProducerRecord<byte[], byte[]> record) {

			Future<RecordMetadata> retVal = super.send(record);

			boolean isRetryTest = "true".equals(MDC.get("KafkaAppenderWithRetryCount"));
			if (isRetryTest) {
				try {
					throw new TimeoutException();
				} catch (TimeoutException e) {
					// TODO Auto-generated catch block
					throw new RuntimeException(e);
				}
			}

			return retVal;
		};

		@Override
		public void close(final long timeout, final TimeUnit timeUnit) {
		}

	};

	private static final String LOG_MESSAGE = "Hello, world!";
	private static final String TOPIC_NAME = "kafka-topic";
	private static final int RETRY_COUNT = 3;

	private static Log4jLogEvent createLogEvent() {
		return Log4jLogEvent.newBuilder().setLoggerName(KafkaAppenderTest.class.getName())
				.setLoggerFqcn(KafkaAppenderTest.class.getName()).setLevel(Level.INFO)
				.setMessage(new SimpleMessage(LOG_MESSAGE)).build();
	}

	@BeforeClass
	public static void setUpClass() throws Exception {
		KafkaManager.producerFactory = config -> kafka;
	}

	@Rule
	public LoggerContextRule ctx = new LoggerContextRule("KafkaAppenderTest.xml");

	@Before
	public void setUp() throws Exception {
		kafka.clear();
	}

	@Test
	public void testAppendWithLayout() throws Exception {
		final Appender appender = ctx.getRequiredAppender("KafkaAppenderWithLayout");
		appender.append(createLogEvent());
		final List<ProducerRecord<byte[], byte[]>> history = kafka.history();
		assertEquals(1, history.size());
		final ProducerRecord<byte[], byte[]> item = history.get(0);
		assertNotNull(item);
		assertEquals(TOPIC_NAME, item.topic());
		assertNull(item.key());
		assertEquals("[" + LOG_MESSAGE + "]", new String(item.value(), StandardCharsets.UTF_8));
	}

	@Test
	public void testAppendWithSerializedLayout() throws Exception {
		final Appender appender = ctx.getRequiredAppender("KafkaAppenderWithSerializedLayout");
		final LogEvent logEvent = createLogEvent();
		appender.append(logEvent);
		final List<ProducerRecord<byte[], byte[]>> history = kafka.history();
		assertEquals(1, history.size());
		final ProducerRecord<byte[], byte[]> item = history.get(0);
		assertNotNull(item);
		assertEquals(TOPIC_NAME, item.topic());
		assertNull(item.key());
		assertEquals(LOG_MESSAGE, deserializeLogEvent(item.value()).getMessage().getFormattedMessage());
	}

	@Test
	public void testAsyncAppend() throws Exception {
		final Appender appender = ctx.getRequiredAppender("AsyncKafkaAppender");
		appender.append(createLogEvent());
		final List<ProducerRecord<byte[], byte[]>> history = kafka.history();
		assertEquals(1, history.size());
		final ProducerRecord<byte[], byte[]> item = history.get(0);
		assertNotNull(item);
		assertEquals(TOPIC_NAME, item.topic());
		assertNull(item.key());
		assertEquals(LOG_MESSAGE, new String(item.value(), StandardCharsets.UTF_8));
	}

	@Test
	public void testAppendWithKey() throws Exception {
		final Appender appender = ctx.getRequiredAppender("KafkaAppenderWithKey");
		final LogEvent logEvent = createLogEvent();
		appender.append(logEvent);
		final List<ProducerRecord<byte[], byte[]>> history = kafka.history();
		assertEquals(1, history.size());
		final ProducerRecord<byte[], byte[]> item = history.get(0);
		assertNotNull(item);
		assertEquals(TOPIC_NAME, item.topic());
		final String msgKey = item.key().toString();
		final byte[] keyValue = "key".getBytes(StandardCharsets.UTF_8);
		assertArrayEquals(item.key(), keyValue);
		assertEquals(LOG_MESSAGE, new String(item.value(), StandardCharsets.UTF_8));
	}

	@Test
	public void testAppendWithKeyLookup() throws Exception {
		final Appender appender = ctx.getRequiredAppender("KafkaAppenderWithKeyLookup");
		final LogEvent logEvent = createLogEvent();
		final Date date = new Date();
		final SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");
		appender.append(logEvent);
		final List<ProducerRecord<byte[], byte[]>> history = kafka.history();
		assertEquals(1, history.size());
		final ProducerRecord<byte[], byte[]> item = history.get(0);
		assertNotNull(item);
		assertEquals(TOPIC_NAME, item.topic());
		final byte[] keyValue = format.format(date).getBytes(StandardCharsets.UTF_8);
		assertArrayEquals(item.key(), keyValue);
		assertEquals(LOG_MESSAGE, new String(item.value(), StandardCharsets.UTF_8));
	}

	@Test
	public void testAppendWithRetryCount() {
		try {
			MDC.put("KafkaAppenderWithRetryCount", "true");
			final Appender appender = ctx.getRequiredAppender("KafkaAppenderWithRetryCount");
			final LogEvent logEvent = createLogEvent();
			appender.append(logEvent);

			final List<ProducerRecord<byte[], byte[]>> history = kafka.history();
			assertEquals(RETRY_COUNT + 1, history.size());
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			MDC.clear();
		}

	}

	private LogEvent deserializeLogEvent(final byte[] data) throws IOException, ClassNotFoundException {
		final ByteArrayInputStream bis = new ByteArrayInputStream(data);
		try (ObjectInput ois = new FilteredObjectInputStream(bis)) {
			return (LogEvent) ois.readObject();
		}
	}

//    public void shouldRetryWhenTimeoutExceptionOccursOnSend() throws Exception {
//        final AtomicInteger attempt = new AtomicInteger(0);
//        final RecordCollectorImpl collector = new RecordCollectorImpl(
//                new MockProducer(cluster, true, new DefaultPartitioner(), byteArraySerializer, byteArraySerializer) {
//                    @Override
//                    public synchronized Future<RecordMetadata> send(final ProducerRecord record, final Callback callback) {
//                        if (attempt.getAndIncrement() == 0) {
//                            throw new TimeoutException();
//                        }
//                        return super.send(record, callback);
//                    }
//                },
//                "test");
//
//        collector.send("topic1", "3", "0", null, stringSerializer, stringSerializer, streamPartitioner);
//        final Long offset = collector.offsets().get(new TopicPartition("topic1", 0));
//        assertEquals(Long.valueOf(0L), offset);
//    }

}