/*
 * 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.beam.sdk.coders;

import static org.hamcrest.Matchers.equalTo;
import static org.junit.Assert.assertThat;

import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import org.apache.beam.sdk.testing.CoderProperties;
import org.apache.beam.sdk.transforms.windowing.GlobalWindow;
import org.apache.beam.sdk.util.CoderUtils;
import org.apache.beam.sdk.values.TypeDescriptor;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.ExpectedException;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Unit tests for {@link IterableCoder}. */
@RunWith(JUnit4.class)
public class IterableCoderTest {

  private static final Coder<Iterable<Integer>> TEST_CODER = IterableCoder.of(VarIntCoder.of());

  private static final List<Iterable<Integer>> TEST_VALUES = Arrays.<Iterable<Integer>>asList(
      Collections.<Integer>emptyList(),
      Collections.<Integer>singletonList(13),
      Arrays.<Integer>asList(1, 2, 3, 4),
      new LinkedList<>(Arrays.asList(7, 6, 5)));

  @Test
  public void testCoderIsSerializableWithWellKnownCoderType() throws Exception {
    CoderProperties.coderSerializable(ListCoder.of(GlobalWindow.Coder.INSTANCE));
  }

  @Test
  public void testDecodeEncodeContentsInSameOrder() throws Exception {
    for (Iterable<Integer> value : TEST_VALUES) {
      CoderProperties.<Integer, Iterable<Integer>>coderDecodeEncodeContentsInSameOrder(
          TEST_CODER, value);
    }
  }

  @Test
  public void testCoderSerializable() throws Exception {
    CoderProperties.coderSerializable(TEST_CODER);
  }

  /**
   * Generated data to check that the wire format has not changed. To regenerate, see
   * {@link org.apache.beam.sdk.coders.PrintBase64Encodings}.
   */
  private static final List<String> TEST_ENCODINGS = Arrays.asList(
      "AAAAAA",
      "AAAAAQ0",
      "AAAABAECAwQ",
      "AAAAAwcGBQ");

  @Test
  public void testWireFormatEncode() throws Exception {
    CoderProperties.coderEncodesBase64(TEST_CODER, TEST_VALUES, TEST_ENCODINGS);
  }

  @Rule
  public ExpectedException thrown = ExpectedException.none();

  @Test
  public void encodeNullThrowsCoderException() throws Exception {
    thrown.expect(CoderException.class);
    thrown.expectMessage("cannot encode a null Iterable");

    CoderUtils.encodeToBase64(TEST_CODER, null);
  }

  @Test
  public void testEncodedTypeDescriptor() throws Exception {
    TypeDescriptor<Iterable<Integer>> typeDescriptor = new TypeDescriptor<Iterable<Integer>>() {};
    assertThat(TEST_CODER.getEncodedTypeDescriptor(), equalTo(typeDescriptor));
  }
}