/*
 * 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.
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package org.apache.accumulo.test;

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

import java.util.HashSet;
import java.util.Map.Entry;

import org.apache.accumulo.core.client.Accumulo;
import org.apache.accumulo.core.client.AccumuloClient;
import org.apache.accumulo.core.client.BatchWriter;
import org.apache.accumulo.core.client.Scanner;
import org.apache.accumulo.core.data.Key;
import org.apache.accumulo.core.data.Mutation;
import org.apache.accumulo.core.data.TableId;
import org.apache.accumulo.core.data.Value;
import org.apache.accumulo.core.dataImpl.KeyExtent;
import org.apache.accumulo.core.metadata.schema.DataFileValue;
import org.apache.accumulo.core.metadata.schema.MetadataSchema.TabletsSection.DataFileColumnFamily;
import org.apache.accumulo.core.metadata.schema.MetadataSchema.TabletsSection.ServerColumnFamily;
import org.apache.accumulo.core.metadata.schema.MetadataSchema.TabletsSection.TabletColumnFamily;
import org.apache.accumulo.core.metadata.schema.TabletDeletedException;
import org.apache.accumulo.core.security.Authorizations;
import org.apache.accumulo.harness.AccumuloClusterHarness;
import org.apache.accumulo.server.util.MetadataTableUtil;
import org.apache.hadoop.io.Text;
import org.junit.Test;

public class CloneIT extends AccumuloClusterHarness {

  @Test
  public void testNoFiles() throws Exception {
    try (AccumuloClient client = Accumulo.newClient().from(getClientProps()).build()) {
      String tableName = getUniqueNames(1)[0];
      client.tableOperations().create(tableName);

      KeyExtent ke = new KeyExtent(TableId.of("0"), null, null);
      Mutation mut = TabletColumnFamily.createPrevRowMutation(ke);

      ServerColumnFamily.TIME_COLUMN.put(mut, new Value("M0"));
      ServerColumnFamily.DIRECTORY_COLUMN.put(mut, new Value("/default_tablet"));

      try (BatchWriter bw1 = client.createBatchWriter(tableName)) {
        bw1.addMutation(mut);
      }

      try (BatchWriter bw2 = client.createBatchWriter(tableName)) {
        MetadataTableUtil.initializeClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);
        int rc =
            MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);
        assertEquals(0, rc);
      }

      // scan tables metadata entries and confirm the same
    }
  }

  @Test
  public void testFilesChange() throws Exception {
    String filePrefix = "hdfs://nn:8000/accumulo/tables/0";
    try (AccumuloClient client = Accumulo.newClient().from(getClientProps()).build()) {
      String tableName = getUniqueNames(1)[0];
      client.tableOperations().create(tableName);

      KeyExtent ke = new KeyExtent(TableId.of("0"), null, null);
      Mutation mut = TabletColumnFamily.createPrevRowMutation(ke);

      ServerColumnFamily.TIME_COLUMN.put(mut, new Value("M0"));
      ServerColumnFamily.DIRECTORY_COLUMN.put(mut, new Value("/default_tablet"));
      mut.put(DataFileColumnFamily.NAME.toString(), filePrefix + "/default_tablet/0_0.rf",
          new DataFileValue(1, 200).encodeAsString());

      try (BatchWriter bw1 = client.createBatchWriter(tableName);
          BatchWriter bw2 = client.createBatchWriter(tableName)) {
        bw1.addMutation(mut);

        bw1.flush();

        MetadataTableUtil.initializeClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        Mutation mut2 = new Mutation(ke.toMetaRow());
        mut2.putDelete(DataFileColumnFamily.NAME.toString(), filePrefix + "/default_tablet/0_0.rf");
        mut2.put(DataFileColumnFamily.NAME.toString(), filePrefix + "/default_tablet/1_0.rf",
            new DataFileValue(2, 300).encodeAsString());

        bw1.addMutation(mut2);
        bw1.flush();

        int rc =
            MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(1, rc);

        rc = MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(0, rc);
      }

      HashSet<String> files = new HashSet<>();

      try (Scanner scanner = client.createScanner(tableName, Authorizations.EMPTY)) {
        scanner.setRange(new KeyExtent(TableId.of("1"), null, null).toMetaRange());
        for (Entry<Key,Value> entry : scanner) {
          if (entry.getKey().getColumnFamily().equals(DataFileColumnFamily.NAME))
            files.add(entry.getKey().getColumnQualifier().toString());
        }
      }
      assertEquals(1, files.size());
      assertTrue(files.contains(filePrefix + "/default_tablet/1_0.rf"));
    }
  }

  // test split where files of children are the same
  @Test
  public void testSplit1() throws Exception {
    String filePrefix = "hdfs://nn:8000/accumulo/tables/0";

    try (AccumuloClient client = Accumulo.newClient().from(getClientProps()).build()) {
      String tableName = getUniqueNames(1)[0];
      client.tableOperations().create(tableName);

      try (BatchWriter bw1 = client.createBatchWriter(tableName);
          BatchWriter bw2 = client.createBatchWriter(tableName)) {
        bw1.addMutation(createTablet("0", null, null, "/default_tablet",
            filePrefix + "/default_tablet/0_0.rf"));

        bw1.flush();

        MetadataTableUtil.initializeClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        bw1.addMutation(
            createTablet("0", "m", null, "/default_tablet", filePrefix + "/default_tablet/0_0.rf"));
        bw1.addMutation(
            createTablet("0", null, "m", "/t-1", filePrefix + "/default_tablet/0_0.rf"));

        bw1.flush();

        int rc =
            MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(0, rc);
      }
      HashSet<String> files = new HashSet<>();
      int count = 0;

      try (Scanner scanner = client.createScanner(tableName, Authorizations.EMPTY)) {
        scanner.setRange(new KeyExtent(TableId.of("1"), null, null).toMetaRange());
        for (Entry<Key,Value> entry : scanner) {
          if (entry.getKey().getColumnFamily().equals(DataFileColumnFamily.NAME)) {
            files.add(entry.getKey().getColumnQualifier().toString());
            count++;
          }
        }
      }
      assertEquals(1, count);
      assertEquals(1, files.size());
      assertTrue(files.contains(filePrefix + "/default_tablet/0_0.rf"));
    }
  }

  // test split where files of children differ... like majc and split occurred
  @Test
  public void testSplit2() throws Exception {
    String filePrefix = "hdfs://nn:8000/accumulo/tables/0";
    try (AccumuloClient client = Accumulo.newClient().from(getClientProps()).build()) {
      String tableName = getUniqueNames(1)[0];
      client.tableOperations().create(tableName);

      try (BatchWriter bw1 = client.createBatchWriter(tableName);
          BatchWriter bw2 = client.createBatchWriter(tableName)) {
        bw1.addMutation(createTablet("0", null, null, "/default_tablet",
            filePrefix + "/default_tablet/0_0.rf"));

        bw1.flush();

        MetadataTableUtil.initializeClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        bw1.addMutation(
            createTablet("0", "m", null, "/default_tablet", filePrefix + "/default_tablet/1_0.rf"));
        Mutation mut3 = createTablet("0", null, "m", "/t-1", filePrefix + "/default_tablet/1_0.rf");
        mut3.putDelete(DataFileColumnFamily.NAME.toString(), filePrefix + "/default_tablet/0_0.rf");
        bw1.addMutation(mut3);

        bw1.flush();

        int rc =
            MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(1, rc);

        rc = MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(0, rc);
      }
      HashSet<String> files = new HashSet<>();
      int count = 0;

      try (Scanner scanner = client.createScanner(tableName, Authorizations.EMPTY)) {
        scanner.setRange(new KeyExtent(TableId.of("1"), null, null).toMetaRange());
        for (Entry<Key,Value> entry : scanner) {
          if (entry.getKey().getColumnFamily().equals(DataFileColumnFamily.NAME)) {
            files.add(entry.getKey().getColumnQualifier().toString());
            count++;
          }
        }
      }
      assertEquals(1, files.size());
      assertEquals(2, count);
      assertTrue(files.contains(filePrefix + "/default_tablet/1_0.rf"));
    }
  }

  private static Mutation deleteTablet(String tid, String endRow, String prevRow, String file) {
    KeyExtent ke = new KeyExtent(TableId.of(tid), endRow == null ? null : new Text(endRow),
        prevRow == null ? null : new Text(prevRow));
    Mutation mut = new Mutation(ke.toMetaRow());
    TabletColumnFamily.PREV_ROW_COLUMN.putDelete(mut);
    ServerColumnFamily.TIME_COLUMN.putDelete(mut);
    ServerColumnFamily.DIRECTORY_COLUMN.putDelete(mut);
    mut.putDelete(DataFileColumnFamily.NAME.toString(), file);

    return mut;
  }

  private static Mutation createTablet(String tid, String endRow, String prevRow, String dir,
      String file) {
    KeyExtent ke = new KeyExtent(TableId.of(tid), endRow == null ? null : new Text(endRow),
        prevRow == null ? null : new Text(prevRow));
    Mutation mut = TabletColumnFamily.createPrevRowMutation(ke);

    ServerColumnFamily.TIME_COLUMN.put(mut, new Value("M0"));
    ServerColumnFamily.DIRECTORY_COLUMN.put(mut, new Value(dir));
    mut.put(DataFileColumnFamily.NAME.toString(), file,
        new DataFileValue(10, 200).encodeAsString());

    return mut;
  }

  // test two tablets splitting into four
  @Test
  public void testSplit3() throws Exception {
    String filePrefix = "hdfs://nn:8000/accumulo/tables/0";
    try (AccumuloClient client = Accumulo.newClient().from(getClientProps()).build()) {
      String tableName = getUniqueNames(1)[0];
      client.tableOperations().create(tableName);

      try (BatchWriter bw1 = client.createBatchWriter(tableName);
          BatchWriter bw2 = client.createBatchWriter(tableName)) {
        bw1.addMutation(createTablet("0", "m", null, "/d1", filePrefix + "/d1/file1"));
        bw1.addMutation(createTablet("0", null, "m", "/d2", filePrefix + "/d2/file2"));

        bw1.flush();

        MetadataTableUtil.initializeClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        bw1.addMutation(createTablet("0", "f", null, "/d1", filePrefix + "/d1/file3"));
        bw1.addMutation(createTablet("0", "m", "f", "/d3", filePrefix + "/d1/file1"));
        bw1.addMutation(createTablet("0", "s", "m", "/d2", filePrefix + "/d2/file2"));
        bw1.addMutation(createTablet("0", null, "s", "/d4", filePrefix + "/d2/file2"));

        bw1.flush();

        int rc =
            MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(0, rc);
      }

      HashSet<String> files = new HashSet<>();
      int count = 0;

      try (Scanner scanner = client.createScanner(tableName, Authorizations.EMPTY)) {
        scanner.setRange(new KeyExtent(TableId.of("1"), null, null).toMetaRange());
        for (Entry<Key,Value> entry : scanner) {
          if (entry.getKey().getColumnFamily().equals(DataFileColumnFamily.NAME)) {
            files.add(entry.getKey().getColumnQualifier().toString());
            count++;
          }
        }
      }
      assertEquals(2, count);
      assertEquals(2, files.size());
      assertTrue(files.contains(filePrefix + "/d1/file1"));
      assertTrue(files.contains(filePrefix + "/d2/file2"));
    }
  }

  // test cloned marker
  @Test
  public void testClonedMarker() throws Exception {
    try (AccumuloClient client = Accumulo.newClient().from(getClientProps()).build()) {
      String tableName = getUniqueNames(1)[0];
      client.tableOperations().create(tableName);
      String filePrefix = "hdfs://nn:8000/accumulo/tables/0";

      try (BatchWriter bw1 = client.createBatchWriter(tableName);
          BatchWriter bw2 = client.createBatchWriter(tableName)) {
        bw1.addMutation(createTablet("0", "m", null, "/d1", filePrefix + "/d1/file1"));
        bw1.addMutation(createTablet("0", null, "m", "/d2", filePrefix + "/d2/file2"));

        bw1.flush();

        MetadataTableUtil.initializeClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        bw1.addMutation(deleteTablet("0", "m", null, filePrefix + "/d1/file1"));
        bw1.addMutation(deleteTablet("0", null, "m", filePrefix + "/d2/file2"));

        bw1.flush();

        bw1.addMutation(createTablet("0", "f", null, "/d1", filePrefix + "/d1/file3"));
        bw1.addMutation(createTablet("0", "m", "f", "/d3", filePrefix + "/d1/file1"));
        bw1.addMutation(createTablet("0", "s", "m", "/d2", filePrefix + "/d2/file3"));
        bw1.addMutation(createTablet("0", null, "s", "/d4", filePrefix + "/d4/file3"));

        bw1.flush();

        int rc =
            MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(1, rc);

        bw1.addMutation(deleteTablet("0", "m", "f", filePrefix + "/d1/file1"));

        bw1.flush();

        bw1.addMutation(createTablet("0", "m", "f", "/d3", filePrefix + "/d1/file3"));

        bw1.flush();

        rc = MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        assertEquals(0, rc);
      }
      HashSet<String> files = new HashSet<>();
      int count = 0;

      try (Scanner scanner = client.createScanner(tableName, Authorizations.EMPTY)) {
        scanner.setRange(new KeyExtent(TableId.of("1"), null, null).toMetaRange());
        for (Entry<Key,Value> entry : scanner) {
          if (entry.getKey().getColumnFamily().equals(DataFileColumnFamily.NAME)) {
            files.add(entry.getKey().getColumnQualifier().toString());
            count++;
          }
        }
      }
      assertEquals(3, count);
      assertEquals(3, files.size());
      assertTrue(files.contains("hdfs://nn:8000/accumulo/tables/0/d1/file1"));
      assertTrue(files.contains("hdfs://nn:8000/accumulo/tables/0/d2/file3"));
      assertTrue(files.contains("hdfs://nn:8000/accumulo/tables/0/d4/file3"));
    }
  }

  // test two tablets splitting into four
  @Test
  public void testMerge() throws Exception {
    String filePrefix = "hdfs://nn:8000/accumulo/tables/0";
    try (AccumuloClient client = Accumulo.newClient().from(getClientProps()).build()) {
      String tableName = getUniqueNames(1)[0];
      client.tableOperations().create(tableName);

      try (BatchWriter bw1 = client.createBatchWriter(tableName);
          BatchWriter bw2 = client.createBatchWriter(tableName)) {
        bw1.addMutation(createTablet("0", "m", null, "/d1", filePrefix + "/d1/file1"));
        bw1.addMutation(createTablet("0", null, "m", "/d2", filePrefix + "/d2/file2"));

        bw1.flush();

        MetadataTableUtil.initializeClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);

        bw1.addMutation(deleteTablet("0", "m", null, filePrefix + "/d1/file1"));
        Mutation mut = createTablet("0", null, null, "/d2", filePrefix + "/d2/file2");
        mut.put(DataFileColumnFamily.NAME.toString(), filePrefix + "/d1/file1",
            new DataFileValue(10, 200).encodeAsString());
        bw1.addMutation(mut);

        bw1.flush();

        try {
          MetadataTableUtil.checkClone(tableName, TableId.of("0"), TableId.of("1"), client, bw2);
          fail();
        } catch (TabletDeletedException tde) {}
      }
    }
  }
}