/*
 * 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.hadoop.hbase.regionserver;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.doAnswer;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

import java.io.IOException;
import java.util.concurrent.BlockingDeque;
import java.util.concurrent.LinkedBlockingDeque;
import java.util.stream.Stream;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseParameterizedTestTemplate;
import org.apache.hadoop.hbase.HBaseTestingUtility;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.ipc.HBaseRpcController;
import org.apache.hadoop.hbase.testclassification.MediumTests;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Tag;
import org.junit.jupiter.api.TestTemplate;
import org.junit.jupiter.params.provider.Arguments;
import org.mockito.Mockito;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;

import org.apache.hbase.thirdparty.com.google.protobuf.RpcController;
import org.apache.hbase.thirdparty.com.google.protobuf.ServiceException;

import org.apache.hadoop.hbase.shaded.protobuf.RequestConverter;
import org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.Action;
import org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.MultiRequest;
import org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.RegionAction;
import org.apache.hadoop.hbase.shaded.protobuf.generated.HBaseProtos;

/**
 * Tests logging of large batch commands via Multi. Tests are fast, but uses a mini-cluster (to test
 * via "Multi" commands) so classified as MediumTests
 */
@Tag(MediumTests.TAG)
@HBaseParameterizedTestTemplate(name = "{index}: rejectLargeBatchOp={0}")
public class TestMultiLogThreshold {

  private static final TableName NAME = TableName.valueOf("tableName");
  private static final byte[] TEST_FAM = Bytes.toBytes("fam");

  private HBaseTestingUtility util;
  private Configuration conf;
  private int threshold;
  private HRegionServer rs;
  private RSRpcServices services;

  private org.apache.logging.log4j.core.Appender appender;

  private final boolean rejectLargeBatchOp;

  public static Stream<Arguments> parameters() {
    return Stream.of(Arguments.of(false), Arguments.of(true));
  }

  public TestMultiLogThreshold(boolean rejectLargeBatchOp) {
    this.rejectLargeBatchOp = rejectLargeBatchOp;
  }

  private final class LevelAndMessage {
    final org.apache.logging.log4j.Level level;

    final String msg;

    public LevelAndMessage(org.apache.logging.log4j.Level level, String msg) {
      this.level = level;
      this.msg = msg;
    }

  }

  // log4j2 will reuse the LogEvent so we need to copy the level and message out.
  private BlockingDeque<LevelAndMessage> logs = new LinkedBlockingDeque<>();

  @BeforeEach
  public void setupTest() throws Exception {
    util = new HBaseTestingUtility();
    conf = util.getConfiguration();
    threshold =
      conf.getInt(HConstants.BATCH_ROWS_THRESHOLD_NAME, HConstants.BATCH_ROWS_THRESHOLD_DEFAULT);
    conf.setBoolean("hbase.rpc.rows.size.threshold.reject", rejectLargeBatchOp);
    util.startMiniCluster();
    util.createTable(NAME, TEST_FAM);
    rs = util.getRSForFirstRegionInTable(NAME);
    appender = mock(org.apache.logging.log4j.core.Appender.class);
    when(appender.getName()).thenReturn("mockAppender");
    when(appender.isStarted()).thenReturn(true);
    doAnswer(new Answer<Void>() {

      @Override
      public Void answer(InvocationOnMock invocation) throws Throwable {
        org.apache.logging.log4j.core.LogEvent logEvent =
          invocation.getArgument(0, org.apache.logging.log4j.core.LogEvent.class);
        logs.add(
          new LevelAndMessage(logEvent.getLevel(), logEvent.getMessage().getFormattedMessage()));
        return null;
      }
    }).when(appender).append(any(org.apache.logging.log4j.core.LogEvent.class));
    ((org.apache.logging.log4j.core.Logger) org.apache.logging.log4j.LogManager
      .getLogger(RSRpcServices.class)).addAppender(appender);
  }

  @AfterEach
  public void tearDown() throws Exception {
    ((org.apache.logging.log4j.core.Logger) org.apache.logging.log4j.LogManager
      .getLogger(RSRpcServices.class)).removeAppender(appender);
    util.shutdownMiniCluster();
  }

  private enum ActionType {
    REGION_ACTIONS,
    ACTIONS
  }

  /**
   * Sends a multi request with a certain amount of rows, will populate Multi command with either
   * "rows" number of RegionActions with one Action each or one RegionAction with "rows" number of
   * Actions
   */
  private void sendMultiRequest(int rows, ActionType actionType)
    throws ServiceException, IOException {
    RpcController rpcc = Mockito.mock(HBaseRpcController.class);
    MultiRequest.Builder builder = MultiRequest.newBuilder();
    int numRAs = 1;
    int numAs = 1;
    switch (actionType) {
      case REGION_ACTIONS:
        numRAs = rows;
        break;
      case ACTIONS:
        numAs = rows;
        break;
    }
    for (int i = 0; i < numRAs; i++) {
      RegionAction.Builder rab = RegionAction.newBuilder();
      rab.setRegion(RequestConverter.buildRegionSpecifier(
        HBaseProtos.RegionSpecifier.RegionSpecifierType.REGION_NAME,
        new String("someStuff" + i).getBytes()));
      for (int j = 0; j < numAs; j++) {
        Action.Builder ab = Action.newBuilder();
        rab.addAction(ab.build());
      }
      builder.addRegionAction(rab.build());
    }
    services = new RSRpcServices(rs);
    services.multi(rpcc, builder.build());
  }

  private void assertLogBatchWarnings(boolean expected) {
    assertFalse(logs.isEmpty());
    boolean actual = false;
    for (LevelAndMessage event : logs) {
      if (
        event.level == org.apache.logging.log4j.Level.WARN
          && event.msg.contains("Large batch operation detected")
      ) {
        actual = true;
        break;
      }
    }
    logs.clear();
    assertEquals(expected, actual);
  }

  @TestTemplate
  public void testMultiLogThresholdRegionActions() throws ServiceException, IOException {
    try {
      sendMultiRequest(threshold + 1, ActionType.REGION_ACTIONS);
      assertFalse(rejectLargeBatchOp);
    } catch (ServiceException e) {
      assertTrue(rejectLargeBatchOp);
    }
    assertLogBatchWarnings(true);

    sendMultiRequest(threshold, ActionType.REGION_ACTIONS);
    assertLogBatchWarnings(false);

    try {
      sendMultiRequest(threshold + 1, ActionType.ACTIONS);
      assertFalse(rejectLargeBatchOp);
    } catch (ServiceException e) {
      assertTrue(rejectLargeBatchOp);
    }
    assertLogBatchWarnings(true);

    sendMultiRequest(threshold, ActionType.ACTIONS);
    assertLogBatchWarnings(false);
  }
}
