track.h

/*
 * Copyright 2025 LiveKit
 *
 * 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.
 */
 
#pragma once
 
#include <cstdint>
#include <future>
#include <memory>
#include <optional>
#include <string>
#include <unordered_map>
#include <vector>
 
#include "livekit/ffi_handle.h"
#include "livekit/stats.h"
#include "livekit/visibility.h"
 
namespace livekit {
 
class LocalTrackPublication;
 
enum class TrackKind {
  KIND_UNKNOWN = 0,
  KIND_AUDIO = 1,
  KIND_VIDEO = 2,
};
 
enum class TrackSource {
  SOURCE_UNKNOWN = 0,
  SOURCE_CAMERA = 1,
  SOURCE_MICROPHONE = 2,
  SOURCE_SCREENSHARE = 3,
  SOURCE_SCREENSHARE_AUDIO = 4,
};
 
enum class StreamState {
  STATE_UNKNOWN = 0,
  STATE_ACTIVE = 1,
  STATE_PAUSED = 2,
};
 
enum class AudioTrackFeature {
  TF_STEREO = 0,
  TF_NO_DTX = 1,
  TF_AUTO_GAIN_CONTROL = 2,
  TF_ECHO_CANCELLATION = 3,
  TF_NOISE_SUPPRESSION = 4,
  TF_ENHANCED_NOISE_CANCELLATION = 5,
  TF_PRECONNECT_BUFFER = 6,
};
 
struct ParticipantTrackPermission {
  std::string participant_identity;
  std::optional<bool> allow_all;
  std::vector<std::string> allowed_track_sids;
};
 
class LIVEKIT_API Track {
public:
  virtual ~Track() = default;
 
  // Read-only properties
  const std::string& sid() const noexcept { return sid_; }
  const std::string& name() const noexcept { return name_; }
  TrackKind kind() const noexcept { return kind_; }
  StreamState streamState() const noexcept { return state_; }
  bool muted() const noexcept { return muted_; }
  bool remote() const noexcept { return remote_; }
 
  // Optional publication info
  std::optional<TrackSource> source() const noexcept { return source_; }
  std::optional<bool> simulcasted() const noexcept { return simulcasted_; }
  std::optional<uint32_t> width() const noexcept { return width_; }
  std::optional<uint32_t> height() const noexcept { return height_; }
  // std::string can actually throw, suppressing for now to maintain API
  // compatibility
  // NOLINTNEXTLINE(bugprone-exception-escape)
  std::optional<std::string> mimeType() const noexcept { return mime_type_; }
 
  // Handle access
  bool hasHandle() const noexcept { return handle_.valid(); }
  uintptr_t ffiHandleId() const noexcept { return handle_.get(); }
 
  // Async get stats
  std::future<std::vector<RtcStats>> getStats() const;
 
  virtual void setPublication(const std::shared_ptr<LocalTrackPublication>& publication) noexcept { (void)publication; }
 
  // Internal updates (called by Room)
  void setStreamState(StreamState s) noexcept { state_ = s; }
  void setMuted(bool m) noexcept { muted_ = m; }
  void setName(std::string n) noexcept { name_ = std::move(n); }
 
protected:
  Track(FfiHandle handle, std::string sid, std::string name, TrackKind kind, StreamState state, bool muted,
        bool remote);
 
  void setPublicationFields(std::optional<TrackSource> source, std::optional<bool> simulcasted,
                            std::optional<uint32_t> width, std::optional<uint32_t> height,
                            std::optional<std::string> mime_type);
 
private:
  FfiHandle handle_; // Owned
 
  std::string sid_;
  std::string name_;
  TrackKind kind_{TrackKind::KIND_UNKNOWN};
  StreamState state_{StreamState::STATE_UNKNOWN};
  bool muted_{false};
  bool remote_{false};
 
  std::optional<TrackSource> source_;
  std::optional<bool> simulcasted_;
  std::optional<uint32_t> width_;
  std::optional<uint32_t> height_;
  std::optional<std::string> mime_type_;
};
 
} // namespace livekit