WIP merge cyclically dependent components into one big component

13 files changed, 0 insertions, 1060 deletions

diff --git a/src/audio/include/audio_converter.hpp b/src/audio/include/audio_converter.hpp
deleted file mode 100644
index 163c6836..00000000
--- a/src/audio/include/audio_converter.hpp
+++ /dev/null
@@ -1,73 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <stdint.h>
-#include <cstdint>
-#include <memory>
-
-#include "audio_events.hpp"
-#include "audio_sink.hpp"
-#include "audio_source.hpp"
-#include "codec.hpp"
-#include "resample.hpp"
-#include "sample.hpp"
-
-namespace audio {
-
-/*
- * Handle to a persistent task that converts samples between formats (sample
- * rate, channels, bits per sample), in order to put samples in the preferred
- * format of the current output device. The resulting samples are forwarded
- * to the output device's sink stream.
- */
-class SampleConverter {
- public:
-  SampleConverter();
-  ~SampleConverter();
-
-  auto SetOutput(std::shared_ptr<IAudioOutput>) -> void;
-
-  auto beginStream(std::shared_ptr<TrackInfo>) -> void;
-  auto continueStream(std::span<sample::Sample>) -> void;
-  auto endStream() -> void;
-
- private:
-  auto Main() -> void;
-
-  auto handleBeginStream(std::shared_ptr<TrackInfo>) -> void;
-  auto handleContinueStream(size_t samples_available) -> void;
-  auto handleEndStream() -> void;
-
-  auto handleSamples(std::span<sample::Sample>) -> size_t;
-
-  auto sendToSink(std::span<sample::Sample>) -> void;
-
-  struct Args {
-    std::shared_ptr<TrackInfo>* track;
-    size_t samples_available;
-    bool is_end_of_stream;
-  };
-  QueueHandle_t commands_;
-
-  std::unique_ptr<Resampler> resampler_;
-
-  StreamBufferHandle_t source_;
-  std::span<sample::Sample> input_buffer_;
-  std::span<std::byte> input_buffer_as_bytes_;
-
-  std::span<sample::Sample> resampled_buffer_;
-
-  std::shared_ptr<IAudioOutput> sink_;
-  IAudioOutput::Format source_format_;
-  IAudioOutput::Format target_format_;
-  size_t leftover_bytes_;
-
-  uint32_t samples_sunk_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/audio_decoder.hpp b/src/audio/include/audio_decoder.hpp
deleted file mode 100644
index 8e955f74..00000000
--- a/src/audio/include/audio_decoder.hpp
+++ /dev/null
@@ -1,56 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <cstdint>
-#include <memory>
-
-#include "audio_converter.hpp"
-#include "audio_events.hpp"
-#include "audio_sink.hpp"
-#include "audio_source.hpp"
-#include "codec.hpp"
-#include "track.hpp"
-#include "types.hpp"
-
-namespace audio {
-
-/*
- * Handle to a persistent task that takes bytes from the given source, decodes
- * them into sample::Sample (normalised to 16 bit signed PCM), and then
- * forwards the resulting stream to the given converter.
- */
-class Decoder {
- public:
-  static auto Start(std::shared_ptr<IAudioSource> source,
-                    std::shared_ptr<SampleConverter> converter) -> Decoder*;
-
-  auto Main() -> void;
-
-  Decoder(const Decoder&) = delete;
-  Decoder& operator=(const Decoder&) = delete;
-
- private:
-  Decoder(std::shared_ptr<IAudioSource> source,
-          std::shared_ptr<SampleConverter> converter);
-
-  auto BeginDecoding(std::shared_ptr<TaggedStream>) -> bool;
-  auto ContinueDecoding() -> bool;
-
-  std::shared_ptr<IAudioSource> source_;
-  std::shared_ptr<SampleConverter> converter_;
-
-  std::shared_ptr<codecs::IStream> stream_;
-  std::unique_ptr<codecs::ICodec> codec_;
-
-  std::optional<codecs::ICodec::OutputFormat> current_format_;
-  std::optional<IAudioOutput::Format> current_sink_format_;
-
-  std::span<sample::Sample> codec_buffer_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/audio_events.hpp b/src/audio/include/audio_events.hpp
deleted file mode 100644
index b8a0dba6..00000000
--- a/src/audio/include/audio_events.hpp
+++ /dev/null
@@ -1,155 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <stdint.h>
-#include <cstdint>
-#include <memory>
-#include <optional>
-#include <string>
-
-#include "audio_sink.hpp"
-#include "tinyfsm.hpp"
-
-#include "track.hpp"
-#include "types.hpp"
-
-namespace audio {
-
-/*
- * Struct encapsulating information about the decoder's current track.
- */
-struct TrackInfo {
-  /*
-   * Audio tags extracted from the file. May be absent for files without any
-   * parseable tags.
-   */
-  std::shared_ptr<database::TrackTags> tags;
-
-  /*
-   * URI that the current track was retrieved from. This is currently always a
-   * file path on the SD card.
-   */
-  std::string uri;
-
-  /*
-   * The length of this track in seconds. This is either retrieved from the
-   * track's tags, or sometimes computed. It may therefore sometimes be
-   * inaccurate or missing.
-   */
-  std::optional<uint32_t> duration;
-
-  /* The offset in seconds that this file's decoding started from. */
-  std::optional<uint32_t> start_offset;
-
-  /* The approximate bitrate of this track in its original encoded form. */
-  std::optional<uint32_t> bitrate_kbps;
-
-  /* The encoded format of the this track. */
-  codecs::StreamType encoding;
-
-  IAudioOutput::Format format;
-};
-
-/*
- * Event emitted by the audio FSM when the state of the audio pipeline has
- * changed. This is usually once per second while a track is playing, plus one
- * event each when a track starts or finishes.
- */
-struct PlaybackUpdate : tinyfsm::Event {
-  /*
-   * The track that is currently being decoded by the audio pipeline. May be
-   * absent if there is no current track.
-   */
-  std::shared_ptr<TrackInfo> current_track;
-
-  /*
-   * How long the current track has been playing for, in seconds. Will always
-   * be present if current_track is present.
-   */
-  std::optional<uint32_t> track_position;
-
-  /* Whether or not the current track is currently being output to a sink. */
-  bool paused;
-};
-
-/*
- * Sets a new track to be decoded by the audio pipeline, replacing any
- * currently playing track.
- */
-struct SetTrack : tinyfsm::Event {
-  std::variant<std::string, database::TrackId, std::monostate> new_track;
-  std::optional<uint32_t> seek_to_second;
-
-  enum Transition {
-    kHardCut,
-    kGapless,
-    // TODO: kCrossFade
-  };
-  Transition transition;
-};
-
-struct TogglePlayPause : tinyfsm::Event {
-  std::optional<bool> set_to;
-};
-
-struct QueueUpdate : tinyfsm::Event {
-  bool current_changed;
-
-  enum Reason {
-    kExplicitUpdate,
-    kRepeatingLastTrack,
-    kTrackFinished,
-    kDeserialised,
-  };
-  Reason reason;
-};
-
-struct StepUpVolume : tinyfsm::Event {};
-struct StepDownVolume : tinyfsm::Event {};
-struct SetVolume : tinyfsm::Event {
-  std::optional<uint_fast8_t> percent;
-  std::optional<int32_t> db;
-};
-struct SetVolumeBalance : tinyfsm::Event {
-  int left_bias;
-};
-
-struct VolumeChanged : tinyfsm::Event {
-  uint_fast8_t percent;
-  int db;
-};
-struct VolumeBalanceChanged : tinyfsm::Event {
-  int left_bias;
-};
-struct VolumeLimitChanged : tinyfsm::Event {
-  int new_limit_db;
-};
-
-struct SetVolumeLimit : tinyfsm::Event {
-  int limit_db;
-};
-
-struct OutputModeChanged : tinyfsm::Event {};
-
-namespace internal {
-
-struct StreamStarted : tinyfsm::Event {
-  std::shared_ptr<TrackInfo> track;
-  IAudioOutput::Format src_format;
-  IAudioOutput::Format dst_format;
-};
-
-struct StreamUpdate : tinyfsm::Event {
-  uint32_t samples_sunk;
-};
-
-struct StreamEnded : tinyfsm::Event {};
-
-}  // namespace internal
-
-}  // namespace audio
diff --git a/src/audio/include/audio_fsm.hpp b/src/audio/include/audio_fsm.hpp
deleted file mode 100644
index 60afb321..00000000
--- a/src/audio/include/audio_fsm.hpp
+++ /dev/null
@@ -1,129 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <stdint.h>
-#include <deque>
-#include <memory>
-#include <vector>
-
-#include "audio_sink.hpp"
-#include "service_locator.hpp"
-#include "tinyfsm.hpp"
-
-#include "audio_decoder.hpp"
-#include "audio_events.hpp"
-#include "bt_audio_output.hpp"
-#include "database.hpp"
-#include "display.hpp"
-#include "fatfs_audio_input.hpp"
-#include "gpios.hpp"
-#include "i2s_audio_output.hpp"
-#include "i2s_dac.hpp"
-#include "storage.hpp"
-#include "system_events.hpp"
-#include "tag_parser.hpp"
-#include "track.hpp"
-#include "track_queue.hpp"
-
-namespace audio {
-
-class AudioState : public tinyfsm::Fsm<AudioState> {
- public:
-  virtual ~AudioState() {}
-
-  virtual void entry() {}
-  virtual void exit() {}
-
-  /* Fallback event handler. Does nothing. */
-  void react(const tinyfsm::Event& ev) {}
-
-  void react(const QueueUpdate&);
-  void react(const SetTrack&);
-  void react(const TogglePlayPause&);
-
-  void react(const internal::StreamStarted&);
-  void react(const internal::StreamUpdate&);
-  void react(const internal::StreamEnded&);
-
-  void react(const StepUpVolume&);
-  void react(const StepDownVolume&);
-  virtual void react(const system_fsm::HasPhonesChanged&);
-
-  void react(const SetVolume&);
-  void react(const SetVolumeLimit&);
-  void react(const SetVolumeBalance&);
-
-  void react(const OutputModeChanged&);
-
-  virtual void react(const system_fsm::BootComplete&) {}
-  virtual void react(const system_fsm::KeyLockChanged&){};
-  virtual void react(const system_fsm::StorageMounted&) {}
-  virtual void react(const system_fsm::BluetoothEvent&);
-
- protected:
-  auto clearDrainBuffer() -> void;
-  auto awaitEmptyDrainBuffer() -> void;
-
-  auto playTrack(database::TrackId id) -> void;
-  auto commitVolume() -> void;
-
-  static std::shared_ptr<system_fsm::ServiceLocator> sServices;
-
-  static std::shared_ptr<FatfsAudioInput> sFileSource;
-  static std::unique_ptr<Decoder> sDecoder;
-  static std::shared_ptr<SampleConverter> sSampleConverter;
-  static std::shared_ptr<I2SAudioOutput> sI2SOutput;
-  static std::shared_ptr<BluetoothAudioOutput> sBtOutput;
-  static std::shared_ptr<IAudioOutput> sOutput;
-
-  static StreamBufferHandle_t sDrainBuffer;
-
-  static std::shared_ptr<TrackInfo> sCurrentTrack;
-  static uint64_t sCurrentSamples;
-  static std::optional<IAudioOutput::Format> sDrainFormat;
-  static bool sCurrentTrackIsFromQueue;
-
-  static std::shared_ptr<TrackInfo> sNextTrack;
-  static uint64_t sNextTrackCueSamples;
-  static bool sNextTrackIsFromQueue;
-
-  static bool sIsResampling;
-  static bool sIsPaused;
-
-  auto currentPositionSeconds() -> std::optional<uint32_t>;
-};
-
-namespace states {
-
-class Uninitialised : public AudioState {
- public:
-  void react(const system_fsm::BootComplete&) override;
-  void react(const system_fsm::BluetoothEvent&) override{};
-
-  using AudioState::react;
-};
-
-class Standby : public AudioState {
- public:
-  void react(const system_fsm::KeyLockChanged&) override;
-  void react(const system_fsm::StorageMounted&) override;
-
-  using AudioState::react;
-};
-
-class Playback : public AudioState {
- public:
-  void entry() override;
-  void exit() override;
-
-  using AudioState::react;
-};
-
-}  // namespace states
-
-}  // namespace audio
diff --git a/src/audio/include/audio_sink.hpp b/src/audio/include/audio_sink.hpp
deleted file mode 100644
index f31d0d75..00000000
--- a/src/audio/include/audio_sink.hpp
+++ /dev/null
@@ -1,87 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <stdint.h>
-#include <cstdint>
-
-#include "esp_heap_caps.h"
-#include "freertos/FreeRTOS.h"
-
-namespace audio {
-
-/*
- * Interface for classes that use PCM samples to create noises for the user.
- *
- * These classes do not generally have any specific task for their work, and
- * simply help to mediate working out the correct PCM format, and then sending
- * those samples to the appropriate hardware driver.
- */
-class IAudioOutput {
- private:
-  StreamBufferHandle_t stream_;
-
- public:
-  IAudioOutput(StreamBufferHandle_t stream)
-      : stream_(stream), mode_(Modes::kOff) {}
-
-  virtual ~IAudioOutput() {}
-
-  enum class Modes {
-    kOff,
-    kOnPaused,
-    kOnPlaying,
-  };
-
-  /*
-   * Indicates whether this output is currently being sent samples. If this is
-   * false, the output should place itself into a low power state.
-   */
-  auto mode(Modes m) -> void {
-    if (mode_ == m) {
-      return;
-    }
-    changeMode(m);
-    mode_ = m;
-  }
-  auto mode() -> Modes { return mode_; }
-
-  virtual auto SetVolumeImbalance(int_fast8_t balance) -> void = 0;
-
-  virtual auto SetVolume(uint16_t) -> void = 0;
-
-  virtual auto GetVolume() -> uint16_t = 0;
-
-  virtual auto GetVolumePct() -> uint_fast8_t = 0;
-  virtual auto GetVolumeDb() -> int_fast16_t = 0;
-
-  virtual auto SetVolumePct(uint_fast8_t) -> bool = 0;
-  virtual auto SetVolumeDb(int_fast16_t) -> bool = 0;
-
-  virtual auto AdjustVolumeUp() -> bool = 0;
-  virtual auto AdjustVolumeDown() -> bool = 0;
-
-  struct Format {
-    uint32_t sample_rate;
-    uint_fast8_t num_channels;
-    uint_fast8_t bits_per_sample;
-
-    bool operator==(const Format&) const = default;
-  };
-
-  virtual auto PrepareFormat(const Format&) -> Format = 0;
-  virtual auto Configure(const Format& format) -> void = 0;
-
-  auto stream() -> StreamBufferHandle_t { return stream_; }
-
- protected:
-  Modes mode_;
-
-  virtual auto changeMode(Modes new_mode) -> void = 0;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/audio_source.hpp b/src/audio/include/audio_source.hpp
deleted file mode 100644
index f6a34300..00000000
--- a/src/audio/include/audio_source.hpp
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <memory>
-#include "codec.hpp"
-#include "track.hpp"
-#include "types.hpp"
-
-namespace audio {
-
-class TaggedStream : public codecs::IStream {
- public:
-  TaggedStream(std::shared_ptr<database::TrackTags>,
-               std::unique_ptr<codecs::IStream> wrapped,
-               std::string path,
-               uint32_t offset = 0
-              );
-
-  auto tags() -> std::shared_ptr<database::TrackTags>;
-
-  auto Read(std::span<std::byte> dest) -> ssize_t override;
-
-  auto CanSeek() -> bool override;
-
-  auto SeekTo(int64_t destination, SeekFrom from) -> void override;
-
-  auto CurrentPosition() -> int64_t override;
-
-  auto Size() -> std::optional<int64_t> override;
-
-  auto Offset() -> uint32_t;
-
-  auto Filepath() -> std::string;
-
-  auto SetPreambleFinished() -> void override;
-
- private:
-  std::shared_ptr<database::TrackTags> tags_;
-  std::unique_ptr<codecs::IStream> wrapped_;
-  std::string filepath_;
-  int32_t offset_;
-};
-
-class IAudioSource {
- public:
-  virtual ~IAudioSource() {}
-
-  virtual auto HasNewStream() -> bool = 0;
-  virtual auto NextStream() -> std::shared_ptr<TaggedStream> = 0;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/bt_audio_output.hpp b/src/audio/include/bt_audio_output.hpp
deleted file mode 100644
index cc3b2462..00000000
--- a/src/audio/include/bt_audio_output.hpp
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <stdint.h>
-#include <cstdint>
-#include <memory>
-#include <vector>
-
-#include "result.hpp"
-
-#include "audio_sink.hpp"
-#include "bluetooth.hpp"
-#include "gpios.hpp"
-#include "i2s_dac.hpp"
-#include "tasks.hpp"
-
-namespace audio {
-
-class BluetoothAudioOutput : public IAudioOutput {
- public:
-  BluetoothAudioOutput(StreamBufferHandle_t,
-                       drivers::Bluetooth& bt,
-                       tasks::WorkerPool&);
-  ~BluetoothAudioOutput();
-
-  auto SetVolumeImbalance(int_fast8_t balance) -> void override;
-
-  auto SetVolume(uint16_t) -> void override;
-
-  auto GetVolume() -> uint16_t override;
-
-  auto GetVolumePct() -> uint_fast8_t override;
-  auto SetVolumePct(uint_fast8_t val) -> bool override;
-  auto GetVolumeDb() -> int_fast16_t override;
-  auto SetVolumeDb(int_fast16_t) -> bool override;
-
-  auto AdjustVolumeUp() -> bool override;
-  auto AdjustVolumeDown() -> bool override;
-
-  auto PrepareFormat(const Format&) -> Format override;
-  auto Configure(const Format& format) -> void override;
-
-  BluetoothAudioOutput(const BluetoothAudioOutput&) = delete;
-  BluetoothAudioOutput& operator=(const BluetoothAudioOutput&) = delete;
-
- protected:
-  auto changeMode(Modes) -> void override;
-
- private:
-  drivers::Bluetooth& bluetooth_;
-  tasks::WorkerPool& bg_worker_;
-
-  uint16_t volume_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/fatfs_audio_input.hpp b/src/audio/include/fatfs_audio_input.hpp
deleted file mode 100644
index 10b7433e..00000000
--- a/src/audio/include/fatfs_audio_input.hpp
+++ /dev/null
@@ -1,66 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <cstddef>
-#include <cstdint>
-#include <future>
-#include <memory>
-#include <string>
-
-#include "ff.h"
-#include "freertos/portmacro.h"
-
-#include "audio_source.hpp"
-#include "codec.hpp"
-#include "future_fetcher.hpp"
-#include "tag_parser.hpp"
-#include "tasks.hpp"
-#include "types.hpp"
-
-namespace audio {
-
-/*
- * Audio source that fetches data from a FatFs (or exfat i guess) filesystem.
- *
- * All public methods are safe to call from any task.
- */
-class FatfsAudioInput : public IAudioSource {
- public:
-  explicit FatfsAudioInput(database::ITagParser&, tasks::WorkerPool&);
-  ~FatfsAudioInput();
-
-  /*
-   * Immediately cease reading any current source, and begin reading from the
-   * given file path.
-   */
-  auto SetPath(std::optional<std::string>) -> void;
-  auto SetPath(const std::string&,uint32_t offset = 0) -> void;
-  auto SetPath() -> void;
-
-  auto HasNewStream() -> bool override;
-  auto NextStream() -> std::shared_ptr<TaggedStream> override;
-
-  FatfsAudioInput(const FatfsAudioInput&) = delete;
-  FatfsAudioInput& operator=(const FatfsAudioInput&) = delete;
-
- private:
-  auto OpenFile(const std::string& path,uint32_t offset) -> bool;
-
-  auto ContainerToStreamType(database::Container)
-      -> std::optional<codecs::StreamType>;
-
-  database::ITagParser& tag_parser_;
-  tasks::WorkerPool& bg_worker_;
-
-  std::mutex new_stream_mutex_;
-  std::shared_ptr<TaggedStream> new_stream_;
-
-  std::atomic<bool> has_new_stream_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/fatfs_source.hpp b/src/audio/include/fatfs_source.hpp
deleted file mode 100644
index ce9b4db8..00000000
--- a/src/audio/include/fatfs_source.hpp
+++ /dev/null
@@ -1,46 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <cstddef>
-#include <cstdint>
-#include <memory>
-
-#include "codec.hpp"
-#include "ff.h"
-
-#include "audio_source.hpp"
-
-namespace audio {
-
-/*
- * Handles coordination with a persistent background task to asynchronously
- * read files from disk into a StreamBuffer.
- */
-class FatfsSource : public codecs::IStream {
- public:
-  FatfsSource(codecs::StreamType, std::unique_ptr<FIL> file);
-  ~FatfsSource();
-
-  auto Read(std::span<std::byte> dest) -> ssize_t override;
-
-  auto CanSeek() -> bool override;
-
-  auto SeekTo(int64_t destination, SeekFrom from) -> void override;
-
-  auto CurrentPosition() -> int64_t override;
-
-  auto Size() -> std::optional<int64_t> override;
-
-  FatfsSource(const FatfsSource&) = delete;
-  FatfsSource& operator=(const FatfsSource&) = delete;
-
- private:
-  std::unique_ptr<FIL> file_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/i2s_audio_output.hpp b/src/audio/include/i2s_audio_output.hpp
deleted file mode 100644
index 7954257a..00000000
--- a/src/audio/include/i2s_audio_output.hpp
+++ /dev/null
@@ -1,63 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <stdint.h>
-#include <cstdint>
-#include <memory>
-#include <vector>
-
-#include "audio_sink.hpp"
-#include "gpios.hpp"
-#include "i2s_dac.hpp"
-#include "result.hpp"
-
-namespace audio {
-
-class I2SAudioOutput : public IAudioOutput {
- public:
-  I2SAudioOutput(StreamBufferHandle_t, drivers::IGpios& expander);
-  ~I2SAudioOutput();
-
-  auto SetMaxVolume(uint16_t) -> void;
-  auto SetVolumeDb(uint16_t) -> void;
-
-  auto SetVolumeImbalance(int_fast8_t balance) -> void override;
-
-  auto SetVolume(uint16_t) -> void override;
-
-  auto GetVolume() -> uint16_t override;
-
-  auto GetVolumePct() -> uint_fast8_t override;
-  auto SetVolumePct(uint_fast8_t val) -> bool override;
-  auto GetVolumeDb() -> int_fast16_t override;
-  auto SetVolumeDb(int_fast16_t) -> bool override;
-
-  auto AdjustVolumeUp() -> bool override;
-  auto AdjustVolumeDown() -> bool override;
-
-  auto PrepareFormat(const Format&) -> Format override;
-  auto Configure(const Format& format) -> void override;
-
-  I2SAudioOutput(const I2SAudioOutput&) = delete;
-  I2SAudioOutput& operator=(const I2SAudioOutput&) = delete;
-
- protected:
-  auto changeMode(Modes) -> void override;
-
- private:
-  drivers::IGpios& expander_;
-  std::unique_ptr<drivers::I2SDac> dac_;
-
-  Modes current_mode_;
-  std::optional<Format> current_config_;
-  int_fast8_t left_difference_;
-  uint16_t current_volume_;
-  uint16_t max_volume_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/readahead_source.hpp b/src/audio/include/readahead_source.hpp
deleted file mode 100644
index 74a30e1b..00000000
--- a/src/audio/include/readahead_source.hpp
+++ /dev/null
@@ -1,60 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <cstddef>
-#include <cstdint>
-#include <memory>
-
-#include "freertos/FreeRTOS.h"
-
-#include "ff.h"
-#include "freertos/stream_buffer.h"
-
-#include "audio_source.hpp"
-#include "codec.hpp"
-#include "tasks.hpp"
-
-namespace audio {
-
-/*
- * Wraps another stream, proactively buffering large chunks of it into memory
- * at a time.
- */
-class ReadaheadSource : public codecs::IStream {
- public:
-  ReadaheadSource(tasks::WorkerPool&, std::unique_ptr<codecs::IStream>);
-  ~ReadaheadSource();
-
-  auto Read(std::span<std::byte> dest) -> ssize_t override;
-
-  auto CanSeek() -> bool override;
-
-  auto SeekTo(int64_t destination, SeekFrom from) -> void override;
-
-  auto CurrentPosition() -> int64_t override;
-
-  auto Size() -> std::optional<int64_t> override;
-
-  auto SetPreambleFinished() -> void override;
-
-  ReadaheadSource(const ReadaheadSource&) = delete;
-  ReadaheadSource& operator=(const ReadaheadSource&) = delete;
-
- private:
-  auto BeginReadahead() -> void;
-
-  tasks::WorkerPool& worker_;
-  std::unique_ptr<codecs::IStream> wrapped_;
-
-  bool readahead_enabled_;
-  std::atomic<bool> is_refilling_;
-  StreamBufferHandle_t buffer_;
-  int64_t tell_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/resample.hpp b/src/audio/include/resample.hpp
deleted file mode 100644
index 4d48d47f..00000000
--- a/src/audio/include/resample.hpp
+++ /dev/null
@@ -1,37 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <cstdint>
-#include <span>
-#include <vector>
-
-#include "speex/speex_resampler.h"
-
-#include "sample.hpp"
-
-namespace audio {
-
-class Resampler {
- public:
-  Resampler(uint32_t source_sample_rate,
-            uint32_t target_sample_rate,
-            uint8_t num_channels);
-
-  ~Resampler();
-
-  auto Process(std::span<sample::Sample> input,
-               std::span<sample::Sample> output,
-               bool end_of_data) -> std::pair<size_t, size_t>;
-
- private:
-  int err_;
-  SpeexResamplerState* resampler_;
-  uint8_t num_channels_;
-};
-
-}  // namespace audio
diff --git a/src/audio/include/track_queue.hpp b/src/audio/include/track_queue.hpp
deleted file mode 100644
index 5b7c9448..00000000
--- a/src/audio/include/track_queue.hpp
+++ /dev/null
@@ -1,170 +0,0 @@
-/*
- * Copyright 2023 jacqueline <me@jacqueline.id.au>
- *
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-#pragma once
-
-#include <list>
-#include <memory>
-#include <mutex>
-#include <shared_mutex>
-#include <vector>
-
-#include "audio_events.hpp"
-#include "cppbor_parse.h"
-#include "database.hpp"
-#include "tasks.hpp"
-#include "track.hpp"
-
-namespace audio {
-
-/*
- * Utility that uses a Miller shuffle to yield well-distributed random indexes
- * from within a range.
- */
-class RandomIterator {
- public:
-  RandomIterator();
-  RandomIterator(size_t size);
-
-  auto current() const -> size_t;
-
-  auto next() -> void;
-  auto prev() -> void;
-
-  // Note resizing has the side-effect of restarting iteration.
-  auto resize(size_t) -> void;
-  auto replay(bool) -> void;
-
-  auto seed() -> size_t& { return seed_; }
-  auto pos() -> size_t& { return pos_; }
-  auto size() -> size_t& { return size_; }
-
- private:
-  size_t seed_;
-  size_t pos_;
-  size_t size_;
-  bool replay_;
-};
-
-/*
- * Owns and manages a complete view of the playback queue. Includes the
- * currently playing track, a truncated list of previously played tracks, and
- * all future tracks that have been queued.
- *
- * In order to not use all of our memory, this class deals strictly with track
- * ids. Consumers that need more data than this should fetch it from the
- * database.
- *
- * Instances of this class are broadly safe to use from multiple tasks; each
- * method represents an atomic operation. No guarantees are made about
- * consistency between calls however.
- */
-class TrackQueue {
- public:
-  TrackQueue(tasks::WorkerPool& bg_worker);
-
-  /* Returns the currently playing track. */
-  auto current() const -> std::optional<database::TrackId>;
-
-  /* Returns, in order, tracks that have been queued to be played next. */
-  auto peekNext(std::size_t limit) const -> std::vector<database::TrackId>;
-
-  /*
-   * Returns the tracks in the queue that have already been played, ordered
-   * most recently played first.
-   */
-  auto peekPrevious(std::size_t limit) const -> std::vector<database::TrackId>;
-
-  auto currentPosition() const -> size_t;
-  auto totalSize() const -> size_t;
-
-  using Item = std::variant<database::TrackId, database::TrackIterator>;
-  auto insert(Item, size_t index = 0) -> void;
-  auto append(Item i) -> void;
-
-  /*
-   * Advances to the next track in the queue, placing the current track at the
-   * front of the 'played' queue.
-   */
-  auto next() -> void;
-  auto previous() -> void;
-
-  /*
-   * Called when the current track finishes
-   */
-  auto finish() -> void;
-
-  auto skipTo(database::TrackId) -> void;
-
-  /*
-   * Removes all tracks from all queues, and stops any currently playing track.
-   */
-  auto clear() -> void;
-
-  auto random(bool) -> void;
-  auto random() const -> bool;
-
-  auto repeat(bool) -> void;
-  auto repeat() const -> bool;
-
-  auto replay(bool) -> void;
-  auto replay() const -> bool;
-
-  auto serialise() -> std::string;
-  auto deserialise(const std::string&) -> void;
-
-  // Cannot be copied or moved.
-  TrackQueue(const TrackQueue&) = delete;
-  TrackQueue& operator=(const TrackQueue&) = delete;
-
- private:
-  auto next(QueueUpdate::Reason r) -> void;
-
-  mutable std::shared_mutex mutex_;
-
-  tasks::WorkerPool& bg_worker_;
-
-  size_t pos_;
-  std::pmr::vector<database::TrackId> tracks_;
-
-  std::optional<RandomIterator> shuffle_;
-  bool repeat_;
-  bool replay_;
-
-  class QueueParseClient : public cppbor::ParseClient {
-   public:
-    QueueParseClient(TrackQueue& queue);
-
-    ParseClient* item(std::unique_ptr<cppbor::Item>& item,
-                      const uint8_t* hdrBegin,
-                      const uint8_t* valueBegin,
-                      const uint8_t* end) override;
-
-    ParseClient* itemEnd(std::unique_ptr<cppbor::Item>& item,
-                         const uint8_t* hdrBegin,
-                         const uint8_t* valueBegin,
-                         const uint8_t* end) override;
-
-    void error(const uint8_t* position,
-               const std::string& errorMessage) override {}
-
-   private:
-    TrackQueue& queue_;
-
-    enum class State {
-      kInit,
-      kRoot,
-      kMetadata,
-      kShuffle,
-      kTracks,
-      kFinished,
-    };
-    State state_;
-    size_t i_;
-  };
-};
-
-}  // namespace audio