/*
 * 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
 *
 *     https://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.avro.perf.test.basic;

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

import org.apache.avro.Schema;
import org.apache.avro.generic.GenericData;
import org.apache.avro.generic.GenericDatumReader;
import org.apache.avro.generic.GenericDatumWriter;
import org.apache.avro.generic.GenericRecord;
import org.apache.avro.io.Decoder;
import org.apache.avro.io.Encoder;
import org.apache.avro.perf.test.BasicState;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.Level;
import org.openjdk.jmh.annotations.OperationsPerInvocation;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.infra.Blackhole;

public class UnchangedUnionTest {

  @Benchmark
  @OperationsPerInvocation(BasicState.BATCH_SIZE)
  public void encode(final TestStateEncode state) throws Exception {
    final Encoder e = state.encoder;
    GenericDatumWriter<Object> writer = new GenericDatumWriter<>(state.schema);
    for (int i = 0; i < state.getBatchSize(); i += 4) {
      writer.write(state.testData[i + 0], e);
      writer.write(state.testData[i + 1], e);
      writer.write(state.testData[i + 2], e);
      writer.write(state.testData[i + 3], e);
    }
  }

  @Benchmark
  @OperationsPerInvocation(BasicState.BATCH_SIZE)
  public void decode(final Blackhole blackHole, final TestStateDecode state) throws Exception {
    final Decoder d = state.decoder;
    final GenericDatumReader<Object> reader = new GenericDatumReader<>(state.schema);
    for (int i = 0; i < state.getBatchSize(); i++) {
      final Object o = reader.read(null, d);
      blackHole.consume(o);
    }
  }

  @State(Scope.Thread)
  public static class TestStateEncode extends BasicState {
    private static final String UNCHANGED_UNION = "[ \"null\", \"int\" ]";

    private GenericRecord[] testData;
    private Encoder encoder;
    private final Schema schema;

    public TestStateEncode() {
      super();
      this.schema = new Schema.Parser().parse(mkSchema(UNCHANGED_UNION));
    }

    /**
     * Setup each trial
     *
     * @throws IOException Could not setup test data
     */
    @Setup(Level.Trial)
    public void doSetupTrial() throws Exception {
      this.encoder = super.newEncoder(false, getNullOutputStream());
      this.testData = new GenericRecord[getBatchSize()];

      for (int i = 0; i < getBatchSize(); i++) {
        final GenericRecord rec = new GenericData.Record(this.schema);

        final int val = super.getRandom().nextInt(1000000);
        final Integer v = (val < 750000 ? new Integer(val) : null);
        rec.put("f", v);

        this.testData[i] = rec;
      }
    }

    private String mkSchema(String subschema) {
      return ("{ \"type\": \"record\", \"name\": \"R\", \"fields\": [\n" + "{ \"name\": \"f\", \"type\": " + subschema
          + "}\n" + "] }");
    }
  }

  @State(Scope.Thread)
  public static class TestStateDecode extends BasicState {

    private static final String UNCHANGED_UNION = "[ \"null\", \"int\" ]";

    private final Schema schema;
    private byte[] testData;
    private Decoder decoder;

    public TestStateDecode() {
      super();
      this.schema = new Schema.Parser().parse(mkSchema(UNCHANGED_UNION));
    }

    /**
     * Generate test data.
     *
     * @throws IOException Could not setup test data
     */
    @Setup(Level.Trial)
    public void doSetupTrial() throws IOException {
      ByteArrayOutputStream baos = new ByteArrayOutputStream();
      Encoder encoder = super.newEncoder(true, baos);

      final GenericDatumWriter<Object> writer = new GenericDatumWriter<>(this.schema);

      for (int i = 0; i < getBatchSize(); i++) {
        final GenericRecord rec = new GenericData.Record(this.schema);
        final int val = super.getRandom().nextInt(1000000);
        final Integer v = (val < 750000 ? new Integer(val) : null);
        rec.put("f", v);

        writer.write(rec, encoder);
      }

      this.testData = baos.toByteArray();
    }

    private String mkSchema(String subschema) {
      return ("{ \"type\": \"record\", \"name\": \"R\", \"fields\": [\n" + "{ \"name\": \"f\", \"type\": " + subschema
          + "}\n" + "] }");
    }

    @Setup(Level.Invocation)
    public void doSetupInvocation() throws Exception {
      this.decoder = super.newDecoder(this.testData);
    }
  }
}