content: /*
   * Copyright (C) 2020 The Android Open Source Project
   *
   * Licensed 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 com.google.android.exoplayer2.decoder;
  
  import static com.google.common.truth.Truth.assertThat;
  import static org.junit.Assert.assertThrows;
  
  import androidx.test.ext.junit.runners.AndroidJUnit4;
  import java.nio.ByteBuffer;
  import java.nio.ByteOrder;
  import java.util.Arrays;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  
  /** Unit tests for {@link DecoderInputBuffer} */
  @RunWith(AndroidJUnit4.class)
  public class DecoderInputBufferTest {
  
    @Test
    public void ensureSpaceForWrite_replacementModeDisabled_doesNothingIfResizeNotNeeded() {
      DecoderInputBuffer buffer =
          new DecoderInputBuffer(DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_DISABLED);
      ByteBuffer data = ByteBuffer.allocate(32);
      buffer.data = data;
      buffer.ensureSpaceForWrite(32);
      assertThat(buffer.data).isSameInstanceAs(data);
    }
  
    @Test
    public void ensureSpaceForWrite_replacementModeDisabled_failsIfResizeNeeded() {
      DecoderInputBuffer buffer =
          new DecoderInputBuffer(DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_DISABLED);
      buffer.data = ByteBuffer.allocate(16);
      assertThrows(IllegalStateException.class, () -> buffer.ensureSpaceForWrite(32));
    }
  
    @Test
    public void ensureSpaceForWrite_usesPaddingSize() {
      DecoderInputBuffer buffer =
          new DecoderInputBuffer(
              DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_NORMAL, /* paddingSize= */ 16);
      buffer.data = ByteBuffer.allocate(32);
      buffer.ensureSpaceForWrite(32);
      assertThat(buffer.data.capacity()).isEqualTo(32 + 16);
    }
  
    @Test
    public void ensureSpaceForWrite_usesPosition() {
      DecoderInputBuffer buffer =
          new DecoderInputBuffer(DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_NORMAL);
      buffer.data = ByteBuffer.wrap(new byte[] {0, 1, 2, 3, 4, 5, 6, 7});
      buffer.data.position(4);
      buffer.ensureSpaceForWrite(12);
      // The new capacity should be the current position (4) + the required space (12).
      assertThat(buffer.data.capacity()).isEqualTo(4 + 12);
      // The current position should have been retained.
      assertThat(buffer.data.position()).isEqualTo(4);
      // Data should have been copied up to the current position.
      byte[] expectedData = Arrays.copyOf(new byte[] {0, 1, 2, 3}, 16);
      assertThat(buffer.data.array()).isEqualTo(expectedData);
    }
  
    @Test
    public void ensureSpaceForWrite_copiesByteOrder() {
      DecoderInputBuffer buffer =
          new DecoderInputBuffer(DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_NORMAL);
      buffer.data = ByteBuffer.allocate(8).order(ByteOrder.LITTLE_ENDIAN);
      buffer.ensureSpaceForWrite(16);
      assertThat(buffer.data.order()).isEqualTo(ByteOrder.LITTLE_ENDIAN);
      buffer.data = ByteBuffer.allocate(8).order(ByteOrder.BIG_ENDIAN);
      buffer.ensureSpaceForWrite(16);
      assertThat(buffer.data.order()).isEqualTo(ByteOrder.BIG_ENDIAN);
    }
  }
  