content: /*
   * Copyright (C) 2016 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.extractor;
  
  import static java.lang.annotation.ElementType.TYPE_USE;
  
  import androidx.annotation.IntDef;
  import androidx.annotation.Nullable;
  import com.google.android.exoplayer2.C;
  import com.google.android.exoplayer2.Format;
  import com.google.android.exoplayer2.upstream.DataReader;
  import com.google.android.exoplayer2.util.ParsableByteArray;
  import java.io.EOFException;
  import java.io.IOException;
  import java.lang.annotation.Documented;
  import java.lang.annotation.Retention;
  import java.lang.annotation.RetentionPolicy;
  import java.lang.annotation.Target;
  import java.util.Arrays;
  
  /** Receives track level data extracted by an {@link Extractor}. */
  public interface TrackOutput {
  
    /** Holds data required to decrypt a sample. */
    final class CryptoData {
  
      /** The encryption mode used for the sample. */
      public final @C.CryptoMode int cryptoMode;
  
      /** The encryption key associated with the sample. Its contents must not be modified. */
      public final byte[] encryptionKey;
  
      /**
       * The number of encrypted blocks in the encryption pattern, 0 if pattern encryption does not
       * apply.
       */
      public final int encryptedBlocks;
  
      /**
       * The number of clear blocks in the encryption pattern, 0 if pattern encryption does not apply.
       */
      public final int clearBlocks;
  
      /**
       * @param cryptoMode See {@link #cryptoMode}.
       * @param encryptionKey See {@link #encryptionKey}.
       * @param encryptedBlocks See {@link #encryptedBlocks}.
       * @param clearBlocks See {@link #clearBlocks}.
       */
      public CryptoData(
          @C.CryptoMode int cryptoMode, byte[] encryptionKey, int encryptedBlocks, int clearBlocks) {
        this.cryptoMode = cryptoMode;
        this.encryptionKey = encryptionKey;
        this.encryptedBlocks = encryptedBlocks;
        this.clearBlocks = clearBlocks;
      }
  
      @Override
      public boolean equals(@Nullable Object obj) {
        if (this == obj) {
          return true;
        }
        if (obj == null || getClass() != obj.getClass()) {
          return false;
        }
        CryptoData other = (CryptoData) obj;
        return cryptoMode == other.cryptoMode
            && encryptedBlocks == other.encryptedBlocks
            && clearBlocks == other.clearBlocks
            && Arrays.equals(encryptionKey, other.encryptionKey);
      }
  
      @Override
      public int hashCode() {
        int result = cryptoMode;
        result = 31 * result + Arrays.hashCode(encryptionKey);
        result = 31 * result + encryptedBlocks;
        result = 31 * result + clearBlocks;
        return result;
      }
    }
  
    /** Defines the part of the sample data to which a call to {@link #sampleData} corresponds. */
    @Documented
    @Retention(RetentionPolicy.SOURCE)
    @Target(TYPE_USE)
    @IntDef({SAMPLE_DATA_PART_MAIN, SAMPLE_DATA_PART_ENCRYPTION, SAMPLE_DATA_PART_SUPPLEMENTAL})
    @interface SampleDataPart {}
  
    /** Main media sample data. */
    int SAMPLE_DATA_PART_MAIN = 0;
    /**
     * Sample encryption data.
     *
     * <p>The format for encryption information is:
     *
     * <ul>
     *   <li>(1 byte) {@code encryption_signal_byte}: Most significant bit signals whether the
     *       encryption data contains subsample encryption data. The remaining bits contain {@code
     *       initialization_vector_size}.
     *   <li>({@code initialization_vector_size} bytes) Initialization vector.
     *   <li>If subsample encryption data is present, as per {@code encryption_signal_byte}, the
     *       encryption data also contains:
     *       <ul>
     *         <li>(2 bytes) {@code subsample_encryption_data_length}.
     *         <li>({@code subsample_encryption_data_length * 6} bytes) Subsample encryption data
     *             (repeated {@code subsample_encryption_data_length} times:
     *             <ul>
     *               <li>(2 bytes) Size of a clear section in sample.
     *               <li>(4 bytes) Size of an encryption section in sample.
     *             </ul>
     *       </ul>
     * </ul>
     */
    int SAMPLE_DATA_PART_ENCRYPTION = 1;
    /**
     * Sample supplemental data.
     *
     * <p>If a sample contains supplemental data, the format of the entire sample data will be:
     *
     * <ul>
     *   <li>If the sample has the {@link C#BUFFER_FLAG_ENCRYPTED} flag set, all encryption
     *       information.
     *   <li>(4 bytes) {@code sample_data_size}: The size of the actual sample data, not including
     *       supplemental data or encryption information.
     *   <li>({@code sample_data_size} bytes): The media sample data.
     *   <li>(remaining bytes) The supplemental data.
     * </ul>
     */
    int SAMPLE_DATA_PART_SUPPLEMENTAL = 2;
  
    /**
     * Called when the {@link Format} of the track has been extracted from the stream.
     *
     * @param format The extracted {@link Format}.
     */
    void format(Format format);
  
    /**
     * Equivalent to {@link #sampleData(DataReader, int, boolean, int) sampleData(input, length,
     * allowEndOfInput, SAMPLE_DATA_PART_MAIN)}.
     */
    default int sampleData(DataReader input, int length, boolean allowEndOfInput) throws IOException {
      return sampleData(input, length, allowEndOfInput, SAMPLE_DATA_PART_MAIN);
    }
  
    /**
     * Equivalent to {@link #sampleData(ParsableByteArray, int, int)} sampleData(data, length,
     * SAMPLE_DATA_PART_MAIN)}.
     */
    default void sampleData(ParsableByteArray data, int length) {
      sampleData(data, length, SAMPLE_DATA_PART_MAIN);
    }
  
    /**
     * Called to write sample data to the output.
     *
     * @param input A {@link DataReader} from which to read the sample data.
     * @param length The maximum length to read from the input.
     * @param allowEndOfInput True if encountering the end of the input having read no data is
     *     allowed, and should result in {@link C#RESULT_END_OF_INPUT} being returned. False if it
     *     should be considered an error, causing an {@link EOFException} to be thrown.
     * @param sampleDataPart The part of the sample data to which this call corresponds.
     * @return The number of bytes appended.
     * @throws IOException If an error occurred reading from the input.
     */
    int sampleData(
        DataReader input, int length, boolean allowEndOfInput, @SampleDataPart int sampleDataPart)
        throws IOException;
  
    /**
     * Called to write sample data to the output.
     *
     * @param data A {@link ParsableByteArray} from which to read the sample data.
     * @param length The number of bytes to read, starting from {@code data.getPosition()}.
     * @param sampleDataPart The part of the sample data to which this call corresponds.
     */
    void sampleData(ParsableByteArray data, int length, @SampleDataPart int sampleDataPart);
  
    /**
     * Called when metadata associated with a sample has been extracted from the stream.
     *
     * <p>The corresponding sample data will have already been passed to the output via calls to
     * {@link #sampleData(DataReader, int, boolean)} or {@link #sampleData(ParsableByteArray, int)}.
     *
     * @param timeUs The media timestamp associated with the sample, in microseconds.
     * @param flags Flags associated with the sample. See {@code C.BUFFER_FLAG_*}.
     * @param size The size of the sample data, in bytes.
     * @param offset The number of bytes that have been passed to {@link #sampleData(DataReader, int,
     *     boolean)} or {@link #sampleData(ParsableByteArray, int)} since the last byte belonging to
     *     the sample whose metadata is being passed.
     * @param cryptoData The encryption data required to decrypt the sample. May be null.
     */
    void sampleMetadata(
        long timeUs, @C.BufferFlags int flags, int size, int offset, @Nullable CryptoData cryptoData);
  }
  