/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MediaData_h
#define MediaData_h

#include "AudioConfig.h"
#include "AudioSampleFormat.h"
#include "EncoderConfig.h"
#include "ImageTypes.h"
#include "MediaResult.h"
#include "SharedBuffer.h"
#include "TimeUnits.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/DefineEnum.h"
#include "mozilla/EnumSet.h"
#include "mozilla/Maybe.h"
#include "mozilla/PodOperations.h"
#include "mozilla/RefPtr.h"
#include "mozilla/Result.h"
#include "mozilla/ResultVariant.h"
#include "mozilla/Span.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/UniquePtrExtensions.h"
#include "mozilla/gfx/Rect.h"
#include "nsString.h"
#include "nsTArray.h"

namespace mozilla {

namespace layers {
class BufferRecycleBin;
class Image;
class ImageContainer;
class KnowsCompositor;
}  // namespace layers

class MediaByteBuffer;
class TrackInfoSharedPtr;

// Backing storage for AlignedBuffer which allows both malloc'd and js_malloc'd
// data to be used.
class BufferStorage {
 public:
  explicit BufferStorage(void* aBuffer, bool aUseJsFree = false)
      : mBuffer(aBuffer), mUseJsFree(aUseJsFree) {}
  BufferStorage(const BufferStorage&) = delete;
  BufferStorage& operator=(const BufferStorage&) = delete;
  BufferStorage(BufferStorage&& aOther)
      : mBuffer(aOther.mBuffer), mUseJsFree(aOther.mUseJsFree) {
    aOther.mBuffer = nullptr;
  }
  BufferStorage& operator=(BufferStorage&& aOther) {
    if (&aOther == this) {
      return *this;
    }
    Deallocate();
    mBuffer = aOther.mBuffer;
    mUseJsFree = aOther.mUseJsFree;
    aOther.mBuffer = nullptr;
    return *this;
  }
  ~BufferStorage() { Deallocate(); }
  size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
    return aMallocSizeOf(mBuffer);
  }

 private:
  void Deallocate() {
    if (mUseJsFree) {
      js_free(mBuffer);
    } else {
      free(mBuffer);
    }
  }
  void* mBuffer;
  bool mUseJsFree;
};

// AlignedBuffer:
// Memory allocations are fallibles. Methods return a boolean indicating if
// memory allocations were successful. Return values should always be checked.
// AlignedBuffer::mData will be nullptr if no memory has been allocated or if
// an error occurred during construction.
// Existing data is only ever modified if new memory allocation has succeeded
// and preserved if not.
//
// The memory referenced by mData will always be Alignment bytes aligned and the
// underlying buffer will always have a size such that Alignment bytes blocks
// can be used to read the content, regardless of the mSize value. Buffer is
// zeroed on creation, elements are not individually constructed.
// An Alignment value of 0 means that the data isn't aligned.
//
// Type must be trivially copyable.
//
// AlignedBuffer can typically be used in place of UniquePtr<Type[]> however
// care must be taken as all memory allocations are fallible.
// Example:
// auto buffer = MakeUniqueFallible<float[]>(samples)
// becomes: AlignedFloatBuffer buffer(samples)
//
// auto buffer = MakeUnique<float[]>(samples)
// becomes:
// AlignedFloatBuffer buffer(samples);
// if (!buffer) { return NS_ERROR_OUT_OF_MEMORY; }
class InflatableShortBuffer;
template <typename Type, int Alignment = 32>
class AlignedBuffer {
 public:
  friend InflatableShortBuffer;
  AlignedBuffer()
      : mData(nullptr), mLength(0), mBuffer(nullptr), mCapacity(0) {}

  explicit AlignedBuffer(size_t aLength)
      : mData(nullptr), mLength(0), mBuffer(nullptr), mCapacity(0) {
    if (EnsureCapacity(aLength)) {
      mLength = aLength;
    }
  }

  AlignedBuffer(const Type* aData, size_t aLength) : AlignedBuffer(aLength) {
    if (!mData) {
      return;
    }
    PodCopy(mData, aData, aLength);
  }

  // Construct AlignedBuffer, taking ownership of data
  AlignedBuffer(Type* aBuffer, size_t aOffset, size_t aLength, bool aUseJsFree)
      : mData(aBuffer + aOffset),
        mLength(aLength),
        mBuffer(aBuffer, aUseJsFree),
        mCapacity(aLength) {
    const uintptr_t alignmask = AlignmentOffset();
    if ((reinterpret_cast<uintptr_t>(mData) & alignmask) != 0) {
      // Create copy of data to ensure correct alignment
      *this = AlignedBuffer(mData, mLength);
    }
  }

  AlignedBuffer(const AlignedBuffer& aOther)
      : AlignedBuffer(aOther.Data(), aOther.Length()) {}

  AlignedBuffer(AlignedBuffer&& aOther) noexcept
      : mData(aOther.mData),
        mLength(aOther.mLength),
        mBuffer(std::move(aOther.mBuffer)),
        mCapacity(aOther.mCapacity) {
    aOther.mData = nullptr;
    aOther.mLength = 0;
    aOther.mCapacity = 0;
  }

  AlignedBuffer& operator=(AlignedBuffer&& aOther) noexcept {
    if (&aOther == this) {
      return *this;
    }
    mData = aOther.mData;
    mLength = aOther.mLength;
    mBuffer = std::move(aOther.mBuffer);
    mCapacity = aOther.mCapacity;
    aOther.mData = nullptr;
    aOther.mLength = 0;
    aOther.mCapacity = 0;
    return *this;
  }

  Type* Data() const { return mData; }
  size_t Length() const { return mLength; }
  size_t Size() const { return mLength * sizeof(Type); }
  Type& operator[](size_t aIndex) {
    MOZ_ASSERT(aIndex < mLength);
    return mData[aIndex];
  }
  const Type& operator[](size_t aIndex) const {
    MOZ_ASSERT(aIndex < mLength);
    return mData[aIndex];
  }
  // Set length of buffer, allocating memory as required.
  // If memory is allocated, additional buffer area is filled with 0.
  [[nodiscard]] bool SetLength(size_t aLength) {
    if (aLength > mLength && !EnsureCapacity(aLength)) {
      return false;
    }
    mLength = aLength;
    return true;
  }
  // Add aData at the beginning of buffer.
  bool Prepend(const Type* aData, size_t aLength) {
    if (!EnsureCapacity(aLength + mLength)) {
      return false;
    }

    // Shift the data to the right by aLength to leave room for the new data.
    PodMove(mData + aLength, mData, mLength);
    PodCopy(mData, aData, aLength);

    mLength += aLength;
    return true;
  }
  // Add aData at the end of buffer.
  bool Append(const Type* aData, size_t aLength) {
    if (!EnsureCapacity(aLength + mLength)) {
      return false;
    }

    PodCopy(mData + mLength, aData, aLength);

    mLength += aLength;
    return true;
  }
  // Replace current content with aData.
  bool Replace(const Type* aData, size_t aLength) {
    // If aLength is smaller than our current length, we leave the buffer as is,
    // only adjusting the reported length.
    if (!EnsureCapacity(aLength)) {
      return false;
    }

    PodCopy(mData, aData, aLength);
    mLength = aLength;
    return true;
  }
  // Clear the memory buffer. Will set target mData and mLength to 0.
  void Clear() {
    mLength = 0;
    mData = nullptr;
  }

  // Methods for reporting memory.
  size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
    return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
  }
  // AlignedBuffer is typically allocated on the stack. As such, you likely
  // want to use SizeOfExcludingThis
  size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
    return mBuffer.SizeOfExcludingThis(aMallocSizeOf);
  }
  size_t ComputedSizeOfExcludingThis() const { return mCapacity; }

  // For backward compatibility with UniquePtr<Type[]>
  Type* get() const { return mData; }
  explicit operator bool() const { return mData != nullptr; }

  // Size in bytes of extra space allocated for padding.
  static size_t AlignmentPaddingSize() { return AlignmentOffset() * 2; }

  void PopFront(size_t aCount) {
    MOZ_DIAGNOSTIC_ASSERT(mLength >= aCount, "Popping too many elements.");
    PodMove(mData, mData + aCount, mLength - aCount);
    mLength -= aCount;
  }

  void PopBack(size_t aCount) {
    MOZ_DIAGNOSTIC_ASSERT(mLength >= aCount, "Popping too many elements.");
    mLength -= aCount;
  }

 private:
  static size_t AlignmentOffset() { return Alignment ? Alignment - 1 : 0; }

  // Ensure that the backend buffer can hold aLength data. Will update mData.
  // Will enforce that the start of allocated data is always Alignment bytes
  // aligned and that it has sufficient end padding to allow for Alignment bytes
  // block read as required by some data decoders.
  // Returns false if memory couldn't be allocated.
  bool EnsureCapacity(size_t aLength) {
    if (!aLength) {
      // No need to allocate a buffer yet.
      return true;
    }
    const CheckedInt<size_t> sizeNeeded =
        CheckedInt<size_t>(aLength) * sizeof(Type) + AlignmentPaddingSize();

    if (!sizeNeeded.isValid() || sizeNeeded.value() >= INT32_MAX) {
      // overflow or over an acceptable size.
      return false;
    }
    if (mData && mCapacity >= sizeNeeded.value()) {
      return true;
    }
    auto newBuffer = MakeUniqueFallible<uint8_t[]>(sizeNeeded.value());
    if (!newBuffer) {
      return false;
    }

    // Find alignment address.
    const uintptr_t alignmask = AlignmentOffset();
    Type* newData = reinterpret_cast<Type*>(
        (reinterpret_cast<uintptr_t>(newBuffer.get()) + alignmask) &
        ~alignmask);
    MOZ_ASSERT(uintptr_t(newData) % (AlignmentOffset() + 1) == 0);

    MOZ_ASSERT(!mLength || mData);

    PodZero(newData + mLength, aLength - mLength);
    if (mLength) {
      PodCopy(newData, mData, mLength);
    }

    mBuffer = BufferStorage(newBuffer.release());
    mCapacity = sizeNeeded.value();
    mData = newData;

    return true;
  }
  Type* mData;
  size_t mLength{};  // number of elements
  BufferStorage mBuffer;
  size_t mCapacity{};  // in bytes
};

using AlignedByteBuffer = AlignedBuffer<uint8_t>;
using AlignedFloatBuffer = AlignedBuffer<float>;
using AlignedShortBuffer = AlignedBuffer<int16_t>;
using AlignedAudioBuffer = AlignedBuffer<AudioDataValue>;

// A buffer in which int16_t audio can be written to, and then converted to
// float32 audio without reallocating.
// This class is useful when an API hands out int16_t audio but the samples
// need to be immediately converted to f32.
class InflatableShortBuffer {
 public:
  explicit InflatableShortBuffer(size_t aElementCount)
      : mBuffer(aElementCount * 2) {}
  AlignedFloatBuffer Inflate() {
    // Convert the data from int16_t to f32 in place, in the same buffer.
    // The reason this works is because the buffer has in fact twice the
    // capacity, and the loop goes backward.
    float* output = reinterpret_cast<float*>(mBuffer.mData);
    for (size_t i = Length(); i--;) {
      output[i] = ConvertAudioSample<float>(mBuffer.mData[i]);
    }
    AlignedFloatBuffer rv;
    rv.mBuffer = std::move(mBuffer.mBuffer);
    rv.mCapacity = mBuffer.mCapacity;
    rv.mLength = Length();
    rv.mData = output;
    return rv;
  }
  size_t Length() const { return mBuffer.mLength / 2; }
  int16_t* get() const { return mBuffer.get(); }
  explicit operator bool() const { return mBuffer.mData != nullptr; }

 protected:
  AlignedShortBuffer mBuffer;
};

// Container that holds media samples.
class MediaData {
 public:
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaData)

  MOZ_DEFINE_ENUM_CLASS_WITH_BASE_AND_TOSTRING_AT_CLASS_SCOPE(
      Type, uint8_t, (AUDIO_DATA, VIDEO_DATA, RAW_DATA, NULL_DATA));

  MediaData(Type aType, int64_t aOffset, const media::TimeUnit& aTimestamp,
            const media::TimeUnit& aDuration)
      : mType(aType),
        mOffset(aOffset),
        mTime(aTimestamp),
        mTimecode(aTimestamp),
        mDuration(aDuration),
        mKeyframe(false) {}

  // Type of contained data.
  const Type mType;

  // Approximate byte offset where this data was demuxed from its media.
  int64_t mOffset;

  // Start time of sample.
  media::TimeUnit mTime;

  // Codec specific internal time code. For Ogg based codecs this is the
  // granulepos.
  media::TimeUnit mTimecode;

  // Duration of sample, in microseconds.
  media::TimeUnit mDuration;

  bool mKeyframe;

  media::TimeUnit GetEndTime() const { return mTime + mDuration; }

  media::TimeUnit GetEndTimecode() const { return mTimecode + mDuration; }

  bool HasValidTime() const {
    return mTime.IsValid() && mTimecode.IsValid() && mDuration.IsValid() &&
           GetEndTime().IsValid() && GetEndTimecode().IsValid();
  }

  template <typename ReturnType>
  const ReturnType* As() const {
    MOZ_RELEASE_ASSERT(this->mType == ReturnType::sType);
    return static_cast<const ReturnType*>(this);
  }

  template <typename ReturnType>
  ReturnType* As() {
    MOZ_RELEASE_ASSERT(this->mType == ReturnType::sType);
    return static_cast<ReturnType*>(this);
  }

 protected:
  explicit MediaData(Type aType) : mType(aType), mOffset(0), mKeyframe(false) {}

  virtual ~MediaData() = default;
};

// NullData is for decoder generating a sample which doesn't need to be
// rendered.
class NullData : public MediaData {
 public:
  NullData(int64_t aOffset, const media::TimeUnit& aTime,
           const media::TimeUnit& aDuration)
      : MediaData(Type::NULL_DATA, aOffset, aTime, aDuration) {}

  static const Type sType = Type::NULL_DATA;
};

// Holds chunk a decoded interleaved audio frames.
class AudioData : public MediaData {
 public:
  AudioData(int64_t aOffset, const media::TimeUnit& aTime,
            AlignedAudioBuffer&& aData, uint32_t aChannels, uint32_t aRate,
            uint32_t aChannelMap = AudioConfig::ChannelLayout::UNKNOWN_MAP);

  static const Type sType = Type::AUDIO_DATA;
  static const char* sTypeName;

  nsCString ToString() const;

  // Access the buffer as a Span.
  Span<AudioDataValue> Data() const;

  // Amount of frames for contained data.
  uint32_t Frames() const { return mFrames; }

  // Trim the audio buffer such that its apparent content fits within the aTrim
  // interval. The actual data isn't removed from the buffer and a followup call
  // to SetTrimWindow could restore the content. mDuration, mTime and mFrames
  // will be adjusted accordingly.
  // Warning: rounding may occurs, in which case the new start time of the audio
  // sample may still be lesser than aTrim.mStart.
  bool SetTrimWindow(const media::TimeInterval& aTrim);

  // Get the internal audio buffer to be moved. After this call the original
  // AudioData will be emptied and can't be used again.
  AlignedAudioBuffer MoveableData();

  size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;

  // If mAudioBuffer is null, creates it from mAudioData.
  void EnsureAudioBuffer();

  // Return true if the adjusted time is valid. Caller should handle error when
  // the result is invalid.
  bool AdjustForStartTime(const media::TimeUnit& aStartTime);

  // This method is used to adjust the original start time, which would change
  //  `mTime` and `mOriginalTime` together, and should only be used for data
  // which hasn't been trimmed before.
  void SetOriginalStartTime(const media::TimeUnit& aStartTime);

  const uint32_t mChannels;
  // The AudioConfig::ChannelLayout map. Channels are ordered as per SMPTE
  // definition. A value of UNKNOWN_MAP indicates unknown layout.
  // ChannelMap is an unsigned bitmap compatible with Windows' WAVE and FFmpeg
  // channel map.
  const AudioConfig::ChannelLayout::ChannelMap mChannelMap;
  const uint32_t mRate;

  // At least one of mAudioBuffer/mAudioData must be non-null.
  // mChannels channels, each with mFrames frames
  RefPtr<SharedBuffer> mAudioBuffer;

 protected:
  ~AudioData() = default;

 private:
  friend class ArrayOfRemoteAudioData;
  AudioDataValue* GetAdjustedData() const;
  media::TimeUnit mOriginalTime;
  // mFrames frames, each with mChannels values
  AlignedAudioBuffer mAudioData;
  Maybe<media::TimeInterval> mTrimWindow;
  // Amount of frames for contained data.
  uint32_t mFrames;
  size_t mDataOffset = 0;
};

namespace layers {
class TextureClient;
class PlanarYCbCrImage;
}  // namespace layers

class VideoInfo;

// Holds a decoded video frame, in YCbCr format. These are queued in the reader.
class VideoData : public MediaData {
 public:
  using IntRect = gfx::IntRect;
  using IntSize = gfx::IntSize;
  using ColorDepth = gfx::ColorDepth;
  using ColorRange = gfx::ColorRange;
  using YUVColorSpace = gfx::YUVColorSpace;
  using ColorSpace2 = gfx::ColorSpace2;
  using ChromaSubsampling = gfx::ChromaSubsampling;
  using ImageContainer = layers::ImageContainer;
  using Image = layers::Image;
  using PlanarYCbCrImage = layers::PlanarYCbCrImage;

  static const Type sType = Type::VIDEO_DATA;
  static const char* sTypeName;

  // YCbCr data obtained from decoding the video. The index's are:
  //   0 = Y
  //   1 = Cb
  //   2 = Cr
  struct YCbCrBuffer {
    struct Plane {
      uint8_t* mData;
      uint32_t mWidth;
      uint32_t mHeight;
      uint32_t mStride;
      uint32_t mSkip;
    };

    Plane mPlanes[3]{};
    YUVColorSpace mYUVColorSpace = YUVColorSpace::Identity;
    ColorSpace2 mColorPrimaries = ColorSpace2::UNKNOWN;
    ColorDepth mColorDepth = ColorDepth::COLOR_8;
    ColorRange mColorRange = ColorRange::LIMITED;
    ChromaSubsampling mChromaSubsampling = ChromaSubsampling::FULL;
  };

  // Extends YCbCrBuffer to support 8-bit per channel conversion with
  // recyclable plane data.
  class QuantizableBuffer final : public YCbCrBuffer {
   public:
    MediaResult To8BitPerChannel(layers::BufferRecycleBin* aRecycleBin);
    ~QuantizableBuffer();

   private:
    void AllocateRecyclableData(uint32_t aLength);

    RefPtr<layers::BufferRecycleBin> mRecycleBin;
    UniquePtr<uint8_t[]> m8bpcPlanes;
    uint32_t mAllocatedLength;
  };

  // Constructs a VideoData object. If aImage is nullptr, creates a new Image
  // holding a copy of the YCbCr data passed in aBuffer. If aImage is not
  // nullptr, it's stored as the underlying video image and aBuffer is assumed
  // to point to memory within aImage so no copy is made. aTimecode is a codec
  // specific number representing the timestamp of the frame of video data.
  // Returns nsnull if an error occurs. This may indicate that memory couldn't
  // be allocated to create the VideoData object, or it may indicate some
  // problem with the input data (e.g. negative stride).

  static bool UseUseNV12ForSoftwareDecodedVideoIfPossible(
      layers::KnowsCompositor* aAllocator);

  // Creates a new VideoData containing a deep copy of aBuffer. May use
  // aContainer to allocate an Image to hold the copied data.
  static Result<already_AddRefed<VideoData>, MediaResult> CreateAndCopyData(
      const VideoInfo& aInfo, ImageContainer* aContainer, int64_t aOffset,
      const media::TimeUnit& aTime, const media::TimeUnit& aDuration,
      const YCbCrBuffer& aBuffer, bool aKeyframe,
      const media::TimeUnit& aTimecode, const IntRect& aPicture,
      layers::KnowsCompositor* aAllocator);

  static Result<already_AddRefed<VideoData>, MediaResult> CreateAndCopyData(
      const VideoInfo& aInfo, ImageContainer* aContainer, int64_t aOffset,
      const media::TimeUnit& aTime, const media::TimeUnit& aDuration,
      const YCbCrBuffer& aBuffer, const YCbCrBuffer::Plane& aAlphaPlane,
      bool aKeyframe, const media::TimeUnit& aTimecode,
      const IntRect& aPicture);

  static already_AddRefed<VideoData> CreateFromImage(
      const IntSize& aDisplay, int64_t aOffset, const media::TimeUnit& aTime,
      const media::TimeUnit& aDuration, const RefPtr<Image>& aImage,
      bool aKeyframe, const media::TimeUnit& aTimecode);

  // Initialize PlanarYCbCrImage. Only When aCopyData is true,
  // video data is copied to PlanarYCbCrImage.
  static MediaResult SetVideoDataToImage(PlanarYCbCrImage* aVideoImage,
                                         const VideoInfo& aInfo,
                                         const YCbCrBuffer& aBuffer,
                                         const IntRect& aPicture,
                                         bool aCopyData);

  size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;

  // Dimensions at which to display the video frame. The picture region
  // will be scaled to this size. This is should be the picture region's
  // dimensions scaled with respect to its aspect ratio.
  const IntSize mDisplay;

  // This frame's image.
  RefPtr<Image> mImage;

  ColorDepth GetColorDepth() const;

  uint32_t mFrameID;

  VideoData(int64_t aOffset, const media::TimeUnit& aTime,
            const media::TimeUnit& aDuration, bool aKeyframe,
            const media::TimeUnit& aTimecode, IntSize aDisplay,
            uint32_t aFrameID);

  nsCString ToString() const;

  void MarkSentToCompositor() { mSentToCompositor = true; }
  bool IsSentToCompositor() { return mSentToCompositor; }

  void UpdateDuration(const media::TimeUnit& aDuration);
  void UpdateTimestamp(const media::TimeUnit& aTimestamp);

  // Return true if the adjusted time is valid. Caller should handle error when
  // the result is invalid.
  bool AdjustForStartTime(const media::TimeUnit& aStartTime);

  void SetNextKeyFrameTime(const media::TimeUnit& aTime) {
    mNextKeyFrameTime = aTime;
  }

  const media::TimeUnit& NextKeyFrameTime() const { return mNextKeyFrameTime; }

 protected:
  ~VideoData();

  bool mSentToCompositor;
  media::TimeUnit mNextKeyFrameTime;
};

// See https://w3c.github.io/encrypted-media/#scheme-cenc
MOZ_DEFINE_ENUM_CLASS_WITH_BASE_AND_TOSTRING(CryptoScheme, uint8_t,
                                             (None, Cenc, Cbcs, Cbcs_1_9));
using CryptoSchemeSet = EnumSet<CryptoScheme, uint8_t>;

nsCString CryptoSchemeSetToString(const CryptoSchemeSet& aSchemes);
CryptoScheme StringToCryptoScheme(const nsAString& aString);

class CryptoTrack {
 public:
  CryptoTrack()
      : mCryptoScheme(CryptoScheme::None),
        mIVSize(0),
        mCryptByteBlock(0),
        mSkipByteBlock(0) {}
  CryptoScheme mCryptoScheme;
  int32_t mIVSize;
  CopyableTArray<uint8_t> mKeyId;
  uint8_t mCryptByteBlock;
  uint8_t mSkipByteBlock;
  CopyableTArray<uint8_t> mConstantIV;

  bool IsEncrypted() const { return mCryptoScheme != CryptoScheme::None; }
};

class CryptoSample : public CryptoTrack {
 public:
  // The num clear bytes in each subsample. The nth element in the array is the
  // number of clear bytes at the start of the nth subsample.
  // Clear sizes are stored as uint16_t in containers per ISO/IEC
  // 23001-7, but we store them as uint32_t for 2 reasons
  // - The Widevine CDM accepts clear sizes as uint32_t.
  // - When converting samples to Annex B we modify the clear sizes and
  //   clear sizes near UINT16_MAX can overflow if stored in a uint16_t.
  CopyableTArray<uint32_t> mPlainSizes;
  // The num encrypted bytes in each subsample. The nth element in the array is
  // the number of encrypted bytes at the start of the nth subsample.
  CopyableTArray<uint32_t> mEncryptedSizes;
  CopyableTArray<uint8_t> mIV;
  CopyableTArray<CopyableTArray<uint8_t>> mInitDatas;
  nsString mInitDataType;
};

// MediaRawData is a MediaData container used to store demuxed, still compressed
// samples.
// Use MediaRawData::CreateWriter() to obtain a MediaRawDataWriter object that
// provides methods to modify and manipulate the data.
// Memory allocations are fallible. Methods return a boolean indicating if
// memory allocations were successful. Return values should always be checked.
// MediaRawData::mData will be nullptr if no memory has been allocated or if
// an error occurred during construction.
// Existing data is only ever modified if new memory allocation has succeeded
// and preserved if not.
//
// The memory referenced by mData will always be 32 bytes aligned and the
// underlying buffer will always have a size such that 32 bytes blocks can be
// used to read the content, regardless of the mSize value. Buffer is zeroed
// on creation.
//
// Typical usage: create new MediaRawData; create the associated
// MediaRawDataWriter, call SetSize() to allocate memory, write to mData,
// up to mSize bytes.

class MediaRawData;

class MediaRawDataWriter {
 public:
  // Pointer to data or null if not-yet allocated
  uint8_t* Data();
  // Writeable size of buffer.
  size_t Size();
  // Writeable reference to MediaRawData::mCryptoInternal
  CryptoSample& mCrypto;

  // Data manipulation methods. mData and mSize may be updated accordingly.

  // Set size of buffer, allocating memory as required.
  // If memory is allocated, additional buffer area is filled with 0.
  [[nodiscard]] bool SetSize(size_t aSize);
  // Add aData at the beginning of buffer.
  [[nodiscard]] bool Prepend(const uint8_t* aData, size_t aSize);
  [[nodiscard]] bool Append(const uint8_t* aData, size_t aSize);
  // Replace current content with aData.
  [[nodiscard]] bool Replace(const uint8_t* aData, size_t aSize);
  // Clear the memory buffer. Will set target mData and mSize to 0.
  void Clear();
  // Remove aSize bytes from the front of the sample.
  void PopFront(size_t aSize);

 private:
  friend class MediaRawData;
  explicit MediaRawDataWriter(MediaRawData* aMediaRawData);
  [[nodiscard]] bool EnsureSize(size_t aSize);
  MediaRawData* mTarget;
};

class MediaRawData final : public MediaData {
 public:
  MediaRawData();
  MediaRawData(const uint8_t* aData, size_t aSize);
  MediaRawData(const uint8_t* aData, size_t aSize, const uint8_t* aAlphaData,
               size_t aAlphaSize);
  explicit MediaRawData(AlignedByteBuffer&& aData);
  MediaRawData(AlignedByteBuffer&& aData, AlignedByteBuffer&& aAlphaData);

  MediaRawData(const MediaRawData&) = delete;

  // Pointer to data or null if not-yet allocated
  const uint8_t* Data() const { return mBuffer.Data(); }
  // Pointer to alpha data or null if not-yet allocated
  const uint8_t* AlphaData() const { return mAlphaBuffer.Data(); }
  // Size of buffer.
  size_t Size() const { return mBuffer.Length(); }
  size_t AlphaSize() const { return mAlphaBuffer.Length(); }
  size_t ComputedSizeOfIncludingThis() const {
    return sizeof(*this) + mBuffer.ComputedSizeOfExcludingThis() +
           mAlphaBuffer.ComputedSizeOfExcludingThis();
  }
  // Access the buffer as a Span.
  operator Span<const uint8_t>() const { return Span{Data(), Size()}; }

  const CryptoSample& mCrypto;
  RefPtr<MediaByteBuffer> mExtraData;

  // Used by the Vorbis decoder and Ogg demuxer.
  // Indicates that this is the last packet of the stream.
  bool mEOS = false;

  RefPtr<TrackInfoSharedPtr> mTrackInfo;

  // Used to indicate the id of the temporal scalability layer.
  Maybe<uint8_t> mTemporalLayerId;

  // May contain the original start time and duration of the frames.
  // mOriginalPresentationWindow.mStart would always be less or equal to mTime
  // and mOriginalPresentationWindow.mEnd equal or greater to mTime + mDuration.
  // This is used when the sample should get cropped so that its content will
  // actually start on mTime and go for mDuration. If this interval is set, then
  // the decoder should crop the content accordingly.
  Maybe<media::TimeInterval> mOriginalPresentationWindow;

  // If it's true, the `mCrypto` should be copied into the remote data as well.
  // Currently this is only used for the media engine DRM playback.
  bool mShouldCopyCryptoToRemoteRawData = false;

  // Config used to encode this packet.
  UniquePtr<const EncoderConfig> mConfig;

  // It's only used when the remote decoder reconstructs the media raw data.
  CryptoSample& GetWritableCrypto() { return mCryptoInternal; }

  // Return a deep copy or nullptr if out of memory.
  already_AddRefed<MediaRawData> Clone() const;
  // Create a MediaRawDataWriter for this MediaRawData. The writer is not
  // thread-safe.
  UniquePtr<MediaRawDataWriter> CreateWriter();
  size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;

 protected:
  ~MediaRawData();

 private:
  friend class MediaRawDataWriter;
  friend class ArrayOfRemoteMediaRawData;
  AlignedByteBuffer mBuffer;
  AlignedByteBuffer mAlphaBuffer;
  CryptoSample mCryptoInternal;
};

// MediaByteBuffer is a ref counted infallible TArray.
class MediaByteBuffer : public nsTArray<uint8_t> {
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaByteBuffer);
  MediaByteBuffer() = default;
  explicit MediaByteBuffer(size_t aCapacity) : nsTArray<uint8_t>(aCapacity) {}

 private:
  ~MediaByteBuffer() = default;
};

// MediaAlignedByteBuffer is a ref counted AlignedByteBuffer whose memory
// allocations are fallible.
class MediaAlignedByteBuffer final : public AlignedByteBuffer {
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaAlignedByteBuffer);
  MediaAlignedByteBuffer() = default;
  MediaAlignedByteBuffer(const uint8_t* aData, size_t aLength)
      : AlignedByteBuffer(aData, aLength) {}
  MediaAlignedByteBuffer(uint8_t* aData, size_t aOffset, size_t aLength,
                         bool aUseJsFree)
      : AlignedByteBuffer(aData, aOffset, aLength, aUseJsFree) {}

 private:
  ~MediaAlignedByteBuffer() = default;
};

}  // namespace mozilla

#endif  // MediaData_h