/**
 *
 * 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.mapred;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;
import static org.mockito.Matchers.any;
import static org.mockito.Matchers.anyInt;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.times;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.PrintStream;

import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.testclassification.MapReduceTests;
import org.apache.hadoop.hbase.testclassification.SmallTests;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.hadoop.hbase.mapred.RowCounter.RowCounterMapper;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.mockito.Mockito;

import com.google.common.base.Joiner;

@Category({MapReduceTests.class, SmallTests.class})
public class TestRowCounter {

  @Test
  @SuppressWarnings("deprecation")
  public void shouldPrintUsage() throws Exception {
    String expectedOutput = "rowcounter <outputdir> <tablename> <column1> [<column2>...]";
    String result = new OutputReader(System.out) {
      @Override
      void doRead() {
        assertEquals(-1, RowCounter.printUsage());
      }
    }.read();

    assertTrue(result.startsWith(expectedOutput));
  }

  @Test
  @SuppressWarnings("deprecation")
  public void shouldExitAndPrintUsageSinceParameterNumberLessThanThree()
      throws Exception {
    final String[] args = new String[] { "one", "two" };
    String line = "ERROR: Wrong number of parameters: " + args.length;
    String result = new OutputReader(System.err) {
      @Override
      void doRead() throws Exception {
        assertEquals(-1, new RowCounter().run(args));
      }
    }.read();

    assertTrue(result.startsWith(line));
  }

  @Test
  @SuppressWarnings({ "deprecation", "unchecked" })
  public void shouldRegInReportEveryIncomingRow() throws IOException {
    int iterationNumber = 999;
    RowCounter.RowCounterMapper mapper = new RowCounter.RowCounterMapper();
    Reporter reporter = mock(Reporter.class);
    for (int i = 0; i < iterationNumber; i++)
      mapper.map(mock(ImmutableBytesWritable.class), mock(Result.class),
          mock(OutputCollector.class), reporter);

    Mockito.verify(reporter, times(iterationNumber)).incrCounter(
        any(Enum.class), anyInt());
  }

  @Test
  @SuppressWarnings({ "deprecation" })
  public void shouldCreateAndRunSubmittableJob() throws Exception {
    RowCounter rCounter = new RowCounter();
    rCounter.setConf(HBaseConfiguration.create());
    String[] args = new String[] { "\temp", "tableA", "column1", "column2",
        "column3" };
    JobConf jobConfig = rCounter.createSubmittableJob(args);

    assertNotNull(jobConfig);
    assertEquals(0, jobConfig.getNumReduceTasks());
    assertEquals("rowcounter", jobConfig.getJobName());
    assertEquals(jobConfig.getMapOutputValueClass(), Result.class);
    assertEquals(jobConfig.getMapperClass(), RowCounterMapper.class);
    assertEquals(jobConfig.get(TableInputFormat.COLUMN_LIST), Joiner.on(' ')
        .join("column1", "column2", "column3"));
    assertEquals(jobConfig.getMapOutputKeyClass(), ImmutableBytesWritable.class);
  }

  enum Outs {
    OUT, ERR
  }

  private static abstract class OutputReader {
    private final PrintStream ps;
    private PrintStream oldPrintStream;
    private Outs outs;

    protected OutputReader(PrintStream ps) {
      this.ps = ps;
    }

    protected String read() throws Exception {
      ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
      if (ps == System.out) {
        oldPrintStream = System.out;
        outs = Outs.OUT;
        System.setOut(new PrintStream(outBytes));
      } else if (ps == System.err) {
        oldPrintStream = System.err;
        outs = Outs.ERR;
        System.setErr(new PrintStream(outBytes));
      } else {
        throw new IllegalStateException("OutputReader: unsupported PrintStream");
      }

      try {
        doRead();
        return new String(outBytes.toByteArray());
      } finally {
        switch (outs) {
        case OUT: {
          System.setOut(oldPrintStream);
          break;
        }
        case ERR: {
          System.setErr(oldPrintStream);
          break;
        }
        default:
          throw new IllegalStateException(
              "OutputReader: unsupported PrintStream");
        }
      }
    }

    abstract void doRead() throws Exception;
  }
}