/**
 *
 * 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.util;

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

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.ClusterMetrics;
import org.apache.hadoop.hbase.ClusterMetrics.Option;
import org.apache.hadoop.hbase.HBaseTestingUtil;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.HRegionLocation;
import org.apache.hadoop.hbase.MetaTableAccessor;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.RegionInfo;
import org.apache.hadoop.hbase.client.RegionLocator;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.client.TableDescriptor;
import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
import org.apache.hadoop.hbase.coprocessor.MasterCoprocessor;
import org.apache.hadoop.hbase.coprocessor.MasterCoprocessorEnvironment;
import org.apache.hadoop.hbase.coprocessor.MasterObserver;
import org.apache.hadoop.hbase.coprocessor.ObserverContext;
import org.apache.hadoop.hbase.master.assignment.AssignmentManager;
import org.apache.hadoop.hbase.master.assignment.RegionStates;
import org.apache.hadoop.hbase.mob.MobFileName;
import org.apache.hadoop.hbase.mob.MobUtils;
import org.apache.hadoop.hbase.regionserver.HRegionFileSystem;
import org.apache.hadoop.hbase.util.hbck.HFileCorruptionChecker;
import org.apache.zookeeper.KeeperException;
import org.junit.rules.TestName;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * This is the base class for  HBaseFsck's ability to detect reasons for inconsistent tables.
 *
 * Actual tests are in :
 * TestHBaseFsckTwoRS
 * TestHBaseFsckOneRS
 * TestHBaseFsckMOB
 * TestHBaseFsckReplicas
 */
public class BaseTestHBaseFsck {
  static final int POOL_SIZE = 7;
  protected static final Logger LOG = LoggerFactory.getLogger(BaseTestHBaseFsck.class);
  protected final static HBaseTestingUtil TEST_UTIL = new HBaseTestingUtil();
  protected final static Configuration conf = TEST_UTIL.getConfiguration();
  protected final static String FAM_STR = "fam";
  protected final static byte[] FAM = Bytes.toBytes(FAM_STR);
  protected final static int REGION_ONLINE_TIMEOUT = 800;
  protected static AssignmentManager assignmentManager;
  protected static RegionStates regionStates;
  protected static ExecutorService tableExecutorService;
  protected static ScheduledThreadPoolExecutor hbfsckExecutorService;
  protected static Connection connection;
  protected static Admin admin;

  // for the instance, reset every test run
  protected Table tbl;
  protected final static byte[][] SPLITS = new byte[][] { Bytes.toBytes("A"),
    Bytes.toBytes("B"), Bytes.toBytes("C") };
  // one row per region.
  protected final static byte[][] ROWKEYS= new byte[][] {
    Bytes.toBytes("00"), Bytes.toBytes("50"), Bytes.toBytes("A0"), Bytes.toBytes("A5"),
    Bytes.toBytes("B0"), Bytes.toBytes("B5"), Bytes.toBytes("C0"), Bytes.toBytes("C5") };

  /**
   * Debugging method to dump the contents of meta.
   */
  protected void dumpMeta(TableName tableName) throws IOException {
    List<RegionInfo> regions =
      MetaTableAccessor.getTableRegions(TEST_UTIL.getConnection(), tableName);
    for (RegionInfo region : regions) {
      LOG.info(region.getRegionNameAsString());
    }
  }

  /**
   * This method is used to undeploy a region -- close it and attempt to
   * remove its state from the Master.
   */
  protected void undeployRegion(Connection conn, ServerName sn,
      RegionInfo hri) throws IOException, InterruptedException {
    try {
      HBaseFsckRepair.closeRegionSilentlyAndWait(conn, sn, hri);
      if (!hri.isMetaRegion()) {
        admin.offline(hri.getRegionName());
      }
    } catch (IOException ioe) {
      LOG.warn("Got exception when attempting to offline region "
          + Bytes.toString(hri.getRegionName()), ioe);
    }
  }
  /**
   * Delete a region from assignments, meta, or completely from hdfs.
   * @param unassign if true unassign region if assigned
   * @param metaRow  if true remove region's row from META
   * @param hdfs if true remove region's dir in HDFS
   */
  protected void deleteRegion(Configuration conf, final TableDescriptor htd,
      byte[] startKey, byte[] endKey, boolean unassign, boolean metaRow,
      boolean hdfs) throws IOException, InterruptedException {
    deleteRegion(conf, htd, startKey, endKey, unassign, metaRow, hdfs, false,
        RegionInfo.DEFAULT_REPLICA_ID);
  }

  /**
   * Delete a region from assignments, meta, or completely from hdfs.
   * @param unassign if true unassign region if assigned
   * @param metaRow  if true remove region's row from META
   * @param hdfs if true remove region's dir in HDFS
   * @param regionInfoOnly if true remove a region dir's .regioninfo file
   * @param replicaId replica id
   */
  protected void deleteRegion(Configuration conf, final TableDescriptor htd,
      byte[] startKey, byte[] endKey, boolean unassign, boolean metaRow,
      boolean hdfs, boolean regionInfoOnly, int replicaId)
          throws IOException, InterruptedException {
    LOG.info("** Before delete:");
    dumpMeta(htd.getTableName());

    List<HRegionLocation> locations;
    try(RegionLocator rl = connection.getRegionLocator(tbl.getName())) {
      locations = rl.getAllRegionLocations();
    }

    for (HRegionLocation location : locations) {
      RegionInfo hri = location.getRegion();
      ServerName hsa = location.getServerName();
      if (Bytes.compareTo(hri.getStartKey(), startKey) == 0
          && Bytes.compareTo(hri.getEndKey(), endKey) == 0
          && hri.getReplicaId() == replicaId) {

        LOG.info("RegionName: " +hri.getRegionNameAsString());
        byte[] deleteRow = hri.getRegionName();

        if (unassign) {
          LOG.info("Undeploying region " + hri + " from server " + hsa);
          undeployRegion(connection, hsa, hri);
        }

        if (regionInfoOnly) {
          LOG.info("deleting hdfs .regioninfo data: " + hri.toString() + hsa.toString());
          Path rootDir = CommonFSUtils.getRootDir(conf);
          FileSystem fs = rootDir.getFileSystem(conf);
          Path p = new Path(CommonFSUtils.getTableDir(rootDir, htd.getTableName()),
              hri.getEncodedName());
          Path hriPath = new Path(p, HRegionFileSystem.REGION_INFO_FILE);
          fs.delete(hriPath, true);
        }

        if (hdfs) {
          LOG.info("deleting hdfs data: " + hri.toString() + hsa.toString());
          Path rootDir = CommonFSUtils.getRootDir(conf);
          FileSystem fs = rootDir.getFileSystem(conf);
          Path p = new Path(CommonFSUtils.getTableDir(rootDir, htd.getTableName()),
              hri.getEncodedName());
          HBaseFsck.debugLsr(conf, p);
          boolean success = fs.delete(p, true);
          LOG.info("Deleted " + p + " sucessfully? " + success);
          HBaseFsck.debugLsr(conf, p);
        }

        if (metaRow) {
          try (Table meta = connection.getTable(TableName.META_TABLE_NAME, tableExecutorService)) {
            Delete delete = new Delete(deleteRow);
            meta.delete(delete);
          }
        }
      }
      LOG.info(hri.toString() + hsa.toString());
    }

    LOG.info("*** After delete:");
    dumpMeta(htd.getTableName());
  }

  /**
   * Setup a clean table before we start mucking with it.
   *
   * It will set tbl which needs to be closed after test
   *
   * @throws IOException
   * @throws InterruptedException
   * @throws KeeperException
   */
  void setupTable(TableName tablename) throws Exception {
    setupTableWithRegionReplica(tablename, 1);
  }

  /**
   * Setup a clean table with a certain region_replica count
   *
   * It will set tbl which needs to be closed after test
   *
   * @throws Exception
   */
  void setupTableWithRegionReplica(TableName tablename, int replicaCount) throws Exception {
    TableDescriptorBuilder tableDescriptorBuilder =
      TableDescriptorBuilder.newBuilder(tablename);
    ColumnFamilyDescriptor columnFamilyDescriptor =
      ColumnFamilyDescriptorBuilder.newBuilder(FAM).build();
    tableDescriptorBuilder.setRegionReplication(replicaCount);
    // If a table has no CF's it doesn't get checked
    tableDescriptorBuilder.setColumnFamily(columnFamilyDescriptor);
    createTable(TEST_UTIL, tableDescriptorBuilder.build(), SPLITS);

    tbl = connection.getTable(tablename, tableExecutorService);
    List<Put> puts = new ArrayList<>(ROWKEYS.length);
    for (byte[] row : ROWKEYS) {
      Put p = new Put(row);
      p.addColumn(FAM, Bytes.toBytes("val"), row);
      puts.add(p);
    }
    tbl.put(puts);
  }

  /**
   * Setup a clean table with a mob-enabled column.
   *
   * @param tablename The name of a table to be created.
   * @throws Exception
   */
  void setupMobTable(TableName tablename) throws Exception {
    TableDescriptorBuilder tableDescriptorBuilder =
      TableDescriptorBuilder.newBuilder(tablename);
    ColumnFamilyDescriptor columnFamilyDescriptor =
      ColumnFamilyDescriptorBuilder
        .newBuilder(FAM)
        .setMobEnabled(true)
        .setMobThreshold(0).build();
    // If a table has no CF's it doesn't get checked
    tableDescriptorBuilder.setColumnFamily(columnFamilyDescriptor);
    createTable(TEST_UTIL, tableDescriptorBuilder.build(), SPLITS);

    tbl = connection.getTable(tablename, tableExecutorService);
    List<Put> puts = new ArrayList<>(ROWKEYS.length);
    for (byte[] row : ROWKEYS) {
      Put p = new Put(row);
      p.addColumn(FAM, Bytes.toBytes("val"), row);
      puts.add(p);
    }
    tbl.put(puts);
  }

  /**
   * Counts the number of rows to verify data loss or non-dataloss.
   */
  int countRows() throws IOException {
     return TEST_UTIL.countRows(tbl);
  }

  /**
   * Counts the number of rows to verify data loss or non-dataloss.
   */
  int countRows(byte[] start, byte[] end) throws IOException {
    return TEST_UTIL.countRows(tbl, new Scan().withStartRow(start).withStopRow(end));
  }

  /**
   * delete table in preparation for next test
   */
  void cleanupTable(TableName tablename) throws Exception {
    if (tbl != null) {
      tbl.close();
      tbl = null;
    }
    connection.clearRegionLocationCache();
    deleteTable(TEST_UTIL, tablename);
  }

  /**
   * Get region info from local cluster.
   */
  Map<ServerName, List<String>> getDeployedHRIs(final Admin admin) throws IOException {
    ClusterMetrics status = admin.getClusterMetrics(EnumSet.of(Option.LIVE_SERVERS));
    Collection<ServerName> regionServers = status.getLiveServerMetrics().keySet();
    Map<ServerName, List<String>> mm = new HashMap<>();
    for (ServerName hsi : regionServers) {
      // list all online regions from this region server
      List<RegionInfo> regions = admin.getRegions(hsi);
      List<String> regionNames = new ArrayList<>(regions.size());
      for (RegionInfo hri : regions) {
        regionNames.add(hri.getRegionNameAsString());
      }
      mm.put(hsi, regionNames);
    }
    return mm;
  }

  /**
   * Returns the HSI a region info is on.
   */
  ServerName findDeployedHSI(Map<ServerName, List<String>> mm, RegionInfo hri) {
    for (Map.Entry<ServerName,List <String>> e : mm.entrySet()) {
      if (e.getValue().contains(hri.getRegionNameAsString())) {
        return e.getKey();
      }
    }
    return null;
  }

  public void deleteTableDir(TableName table) throws IOException {
    Path rootDir = CommonFSUtils.getRootDir(conf);
    FileSystem fs = rootDir.getFileSystem(conf);
    Path p = CommonFSUtils.getTableDir(rootDir, table);
    HBaseFsck.debugLsr(conf, p);
    boolean success = fs.delete(p, true);
    LOG.info("Deleted " + p + " sucessfully? " + success);
  }

  /**
   * We don't have an easy way to verify that a flush completed, so we loop until we find a
   * legitimate hfile and return it.
   * @param fs
   * @param table
   * @return Path of a flushed hfile.
   * @throws IOException
   */
  Path getFlushedHFile(FileSystem fs, TableName table) throws IOException {
    Path tableDir= CommonFSUtils.getTableDir(CommonFSUtils.getRootDir(conf), table);
    Path regionDir = FSUtils.getRegionDirs(fs, tableDir).get(0);
    Path famDir = new Path(regionDir, FAM_STR);

    // keep doing this until we get a legit hfile
    while (true) {
      FileStatus[] hfFss = fs.listStatus(famDir);
      if (hfFss.length == 0) {
        continue;
      }
      for (FileStatus hfs : hfFss) {
        if (!hfs.isDirectory()) {
          return hfs.getPath();
        }
      }
    }
  }

  /**
   * Gets flushed mob files.
   * @param fs The current file system.
   * @param table The current table name.
   * @return Path of a flushed hfile.
   * @throws IOException
   */
  Path getFlushedMobFile(FileSystem fs, TableName table) throws IOException {
    Path famDir = MobUtils.getMobFamilyPath(conf, table, FAM_STR);

    // keep doing this until we get a legit hfile
    while (true) {
      FileStatus[] hfFss = fs.listStatus(famDir);
      if (hfFss.length == 0) {
        continue;
      }
      for (FileStatus hfs : hfFss) {
        if (!hfs.isDirectory()) {
          return hfs.getPath();
        }
      }
    }
  }

  /**
   * Creates a new mob file name by the old one.
   * @param oldFileName The old mob file name.
   * @return The new mob file name.
   */
  String createMobFileName(String oldFileName) {
    MobFileName mobFileName = MobFileName.create(oldFileName);
    String startKey = mobFileName.getStartKey();
    String date = mobFileName.getDate();
    return MobFileName.create(startKey, date,
                              TEST_UTIL.getRandomUUID().toString().replaceAll("-", ""), "abcdef")
      .getFileName();
  }


  /**
   * Test that use this should have a timeout, because this method could potentially wait forever.
  */
  protected void doQuarantineTest(TableName table, HBaseFsck hbck, int check,
                                  int corrupt, int fail, int quar, int missing) throws Exception {
    try {
      setupTable(table);
      assertEquals(ROWKEYS.length, countRows());
      admin.flush(table); // flush is async.

      // Mess it up by leaving a hole in the assignment, meta, and hdfs data
      admin.disableTable(table);

      String[] args = {"-sidelineCorruptHFiles", "-repairHoles", "-ignorePreCheckPermission",
          table.getNameAsString()};
      HBaseFsck res = hbck.exec(hbfsckExecutorService, args);

      HFileCorruptionChecker hfcc = res.getHFilecorruptionChecker();
      assertEquals(hfcc.getHFilesChecked(), check);
      assertEquals(hfcc.getCorrupted().size(), corrupt);
      assertEquals(hfcc.getFailures().size(), fail);
      assertEquals(hfcc.getQuarantined().size(), quar);
      assertEquals(hfcc.getMissing().size(), missing);

      // its been fixed, verify that we can enable
      admin.enableTableAsync(table);
      while (!admin.isTableEnabled(table)) {
        try {
          Thread.sleep(250);
        } catch (InterruptedException e) {
          e.printStackTrace();
          fail("Interrupted when trying to enable table " + table);
        }
      }
    } finally {
      cleanupTable(table);
    }
  }


  static class MockErrorReporter implements HbckErrorReporter {
    static int calledCount = 0;

    @Override
    public void clear() {
      calledCount++;
    }

    @Override
    public void report(String message) {
      calledCount++;
    }

    @Override
    public void reportError(String message) {
      calledCount++;
    }

    @Override
    public void reportError(ERROR_CODE errorCode, String message) {
      calledCount++;
    }

    @Override
    public void reportError(ERROR_CODE errorCode, String message, HbckTableInfo table) {
      calledCount++;
    }

    @Override
    public void reportError(ERROR_CODE errorCode,
        String message, HbckTableInfo table, HbckRegionInfo info) {
      calledCount++;
    }

    @Override
    public void reportError(ERROR_CODE errorCode, String message,
        HbckTableInfo table, HbckRegionInfo info1, HbckRegionInfo info2) {
      calledCount++;
    }

    @Override
    public int summarize() {
      return ++calledCount;
    }

    @Override
    public void detail(String details) {
      calledCount++;
    }

    @Override
    public ArrayList<ERROR_CODE> getErrorList() {
      calledCount++;
      return new ArrayList<>();
    }

    @Override
    public void progress() {
      calledCount++;
    }

    @Override
    public void print(String message) {
      calledCount++;
    }

    @Override
    public void resetErrors() {
      calledCount++;
    }

    @Override
    public boolean tableHasErrors(HbckTableInfo table) {
      calledCount++;
      return false;
    }
  }


  protected void deleteMetaRegion(Configuration conf, boolean unassign, boolean hdfs,
                                  boolean regionInfoOnly) throws IOException, InterruptedException {
    HRegionLocation metaLocation = connection.getRegionLocator(TableName.META_TABLE_NAME)
        .getRegionLocation(HConstants.EMPTY_START_ROW);
    ServerName hsa = metaLocation.getServerName();
    RegionInfo hri = metaLocation.getRegion();
    if (unassign) {
      LOG.info("Undeploying meta region " + hri + " from server " + hsa);
      try (Connection unmanagedConnection = ConnectionFactory.createConnection(conf)) {
        undeployRegion(unmanagedConnection, hsa, hri);
      }
    }

    if (regionInfoOnly) {
      LOG.info("deleting hdfs .regioninfo data: " + hri.toString() + hsa.toString());
      Path rootDir = CommonFSUtils.getRootDir(conf);
      FileSystem fs = rootDir.getFileSystem(conf);
      Path p = new Path(rootDir + "/" + TableName.META_TABLE_NAME.getNameAsString(),
          hri.getEncodedName());
      Path hriPath = new Path(p, HRegionFileSystem.REGION_INFO_FILE);
      fs.delete(hriPath, true);
    }

    if (hdfs) {
      LOG.info("deleting hdfs data: " + hri.toString() + hsa.toString());
      Path rootDir = CommonFSUtils.getRootDir(conf);
      FileSystem fs = rootDir.getFileSystem(conf);
      Path p = new Path(rootDir + "/" + TableName.META_TABLE_NAME.getNameAsString(),
          hri.getEncodedName());
      HBaseFsck.debugLsr(conf, p);
      boolean success = fs.delete(p, true);
      LOG.info("Deleted " + p + " sucessfully? " + success);
      HBaseFsck.debugLsr(conf, p);
    }
  }

  @org.junit.Rule
  public TestName name = new TestName();

  public static class MasterSyncCoprocessor implements MasterCoprocessor, MasterObserver {
    volatile CountDownLatch tableCreationLatch = null;
    volatile CountDownLatch tableDeletionLatch = null;

    @Override
    public Optional<MasterObserver> getMasterObserver() {
      return Optional.of(this);
    }

    @Override
    public void postCompletedCreateTableAction(
        final ObserverContext<MasterCoprocessorEnvironment> ctx,
        final TableDescriptor desc,
        final RegionInfo[] regions) throws IOException {
      // the AccessController test, some times calls only and directly the
      // postCompletedCreateTableAction()
      if (tableCreationLatch != null) {
        tableCreationLatch.countDown();
      }
    }

    @Override
    public void postCompletedDeleteTableAction(
        final ObserverContext<MasterCoprocessorEnvironment> ctx,
        final TableName tableName) throws IOException {
      // the AccessController test, some times calls only and directly the
      // postCompletedDeleteTableAction()
      if (tableDeletionLatch != null) {
        tableDeletionLatch.countDown();
      }
    }
  }

  public static void createTable(HBaseTestingUtil testUtil, TableDescriptor tableDescriptor,
      byte[][] splitKeys) throws Exception {
    // NOTE: We need a latch because admin is not sync,
    // so the postOp coprocessor method may be called after the admin operation returned.
    MasterSyncCoprocessor coproc = testUtil.getHBaseCluster().getMaster()
        .getMasterCoprocessorHost().findCoprocessor(MasterSyncCoprocessor.class);
    coproc.tableCreationLatch = new CountDownLatch(1);
    if (splitKeys != null) {
      admin.createTable(tableDescriptor, splitKeys);
    } else {
      admin.createTable(tableDescriptor);
    }
    coproc.tableCreationLatch.await();
    coproc.tableCreationLatch = null;
    testUtil.waitUntilAllRegionsAssigned(tableDescriptor.getTableName());
  }

  public static void deleteTable(HBaseTestingUtil testUtil, TableName tableName)
    throws Exception {
    // NOTE: We need a latch because admin is not sync,
    // so the postOp coprocessor method may be called after the admin operation returned.
    MasterSyncCoprocessor coproc = testUtil.getHBaseCluster().getMaster()
      .getMasterCoprocessorHost().findCoprocessor(MasterSyncCoprocessor.class);
    coproc.tableDeletionLatch = new CountDownLatch(1);
    try {
      admin.disableTable(tableName);
    } catch (Exception e) {
      LOG.debug("Table: " + tableName + " already disabled, so just deleting it.");
    }
    admin.deleteTable(tableName);
    coproc.tableDeletionLatch.await();
    coproc.tableDeletionLatch = null;
  }
}