/* 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 SamplesWaitingForKey_h_
#define SamplesWaitingForKey_h_

#include <functional>

#include "MediaInfo.h"
#include "mozilla/MozPromise.h"
#include "mozilla/Mutex.h"
#include "mozilla/RefPtr.h"

namespace mozilla {

typedef nsTArray<uint8_t> CencKeyId;

class CDMProxy;
template <typename... Es>
class MediaEventProducer;
class MediaRawData;

// Encapsulates the task of waiting for the CDMProxy to have the necessary
// keys to decrypt a given sample.
class SamplesWaitingForKey {
 public:
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(SamplesWaitingForKey)

  typedef MozPromise<RefPtr<MediaRawData>, bool, /* IsExclusive = */ true>
      WaitForKeyPromise;

  SamplesWaitingForKey(
      CDMProxy* aProxy, TrackInfo::TrackType aType,
      const std::function<MediaEventProducer<TrackInfo::TrackType>*()>&
          aOnWaitingForKeyEvent);

  // Returns a promise that will be resolved if or when a key for decoding the
  // sample becomes usable.
  RefPtr<WaitForKeyPromise> WaitIfKeyNotUsable(MediaRawData* aSample);

  void NotifyUsable(const CencKeyId& aKeyId);

  void Flush();

  void BreakCycles();

 protected:
  ~SamplesWaitingForKey();

 private:
  Mutex mMutex MOZ_UNANNOTATED;
  RefPtr<CDMProxy> mProxy;
  struct SampleEntry {
    RefPtr<MediaRawData> mSample;
    MozPromiseHolder<WaitForKeyPromise> mPromise;
  };
  nsTArray<SampleEntry> mSamples;
  const TrackInfo::TrackType mType;
  const std::function<MediaEventProducer<TrackInfo::TrackType>*()>
      mOnWaitingForKeyEvent;
};

}  // namespace mozilla

#endif  //  SamplesWaitingForKey_h_