6 files changed, 36 insertions, 9 deletions

diff --git a/src/audio/include/audio_events.hpp b/src/audio/include/audio_events.hpp
index 03584062..a79ca4ec 100644
--- a/src/audio/include/audio_events.hpp
+++ b/src/audio/include/audio_events.hpp
@@ -14,7 +14,6 @@
 #include "tinyfsm.hpp"
 
 #include "track.hpp"
-#include "track_queue.hpp"
 #include "types.hpp"
 
 namespace audio {
@@ -39,6 +38,13 @@ struct PlaybackStopped : tinyfsm::Event {};
 
 struct QueueUpdate : tinyfsm::Event {
   bool current_changed;
+
+  enum Reason {
+    kExplicitUpdate,
+    kRepeatingLastTrack,
+    kTrackFinished,
+  };
+  Reason reason;
 };
 
 struct PlayFile : tinyfsm::Event {
diff --git a/src/audio/include/audio_fsm.hpp b/src/audio/include/audio_fsm.hpp
index 29ec489a..2d335e74 100644
--- a/src/audio/include/audio_fsm.hpp
+++ b/src/audio/include/audio_fsm.hpp
@@ -52,7 +52,7 @@ class AudioState : public tinyfsm::Fsm<AudioState> {
   void react(const OutputModeChanged&);
 
   virtual void react(const system_fsm::BootComplete&) {}
-  virtual void react(const system_fsm::KeyLockChanged&) {};
+  virtual void react(const system_fsm::KeyLockChanged&){};
   virtual void react(const system_fsm::StorageMounted&) {}
   virtual void react(const system_fsm::BluetoothEvent&);
 
@@ -67,6 +67,7 @@ class AudioState : public tinyfsm::Fsm<AudioState> {
   virtual void react(const internal::AudioPipelineIdle&) {}
 
  protected:
+  auto clearDrainBuffer() -> void;
   auto playTrack(database::TrackId id) -> void;
   auto commitVolume() -> void;
 
@@ -79,6 +80,8 @@ class AudioState : public tinyfsm::Fsm<AudioState> {
   static std::shared_ptr<BluetoothAudioOutput> sBtOutput;
   static std::shared_ptr<IAudioOutput> sOutput;
 
+  static StreamBufferHandle_t sDrainBuffer;
+
   static std::optional<database::TrackId> sCurrentTrack;
 
   auto readyToPlay() -> bool;
@@ -91,7 +94,7 @@ class Uninitialised : public AudioState {
  public:
   void react(const system_fsm::BootComplete&) override;
 
-  void react(const system_fsm::BluetoothEvent&) override {};
+  void react(const system_fsm::BluetoothEvent&) override{};
 
   using AudioState::react;
 };
diff --git a/src/audio/include/audio_sink.hpp b/src/audio/include/audio_sink.hpp
index eba55eb5..85c23f5c 100644
--- a/src/audio/include/audio_sink.hpp
+++ b/src/audio/include/audio_sink.hpp
@@ -27,7 +27,8 @@ class IAudioOutput {
   StreamBufferHandle_t stream_;
 
  public:
-  IAudioOutput(StreamBufferHandle_t stream) : stream_(stream) {}
+  IAudioOutput(StreamBufferHandle_t stream)
+      : stream_(stream), mode_(Modes::kOff) {}
 
   virtual ~IAudioOutput() {}
 
@@ -41,7 +42,14 @@ class IAudioOutput {
    * Indicates whether this output is currently being sent samples. If this is
    * false, the output should place itself into a low power state.
    */
-  virtual auto SetMode(Modes) -> void = 0;
+  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;
 
@@ -67,6 +75,11 @@ class IAudioOutput {
   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/bt_audio_output.hpp b/src/audio/include/bt_audio_output.hpp
index f6d2200c..a61e718a 100644
--- a/src/audio/include/bt_audio_output.hpp
+++ b/src/audio/include/bt_audio_output.hpp
@@ -28,8 +28,6 @@ class BluetoothAudioOutput : public IAudioOutput {
                        tasks::WorkerPool&);
   ~BluetoothAudioOutput();
 
-  auto SetMode(Modes) -> void override;
-
   auto SetVolumeImbalance(int_fast8_t balance) -> void override;
 
   auto SetVolume(uint16_t) -> void override;
@@ -48,6 +46,9 @@ class BluetoothAudioOutput : public IAudioOutput {
   BluetoothAudioOutput(const BluetoothAudioOutput&) = delete;
   BluetoothAudioOutput& operator=(const BluetoothAudioOutput&) = delete;
 
+ protected:
+  auto changeMode(Modes) -> void override;
+
  private:
   drivers::Bluetooth& bluetooth_;
   tasks::WorkerPool& bg_worker_;
diff --git a/src/audio/include/i2s_audio_output.hpp b/src/audio/include/i2s_audio_output.hpp
index 7c297106..5f3fc3ff 100644
--- a/src/audio/include/i2s_audio_output.hpp
+++ b/src/audio/include/i2s_audio_output.hpp
@@ -23,8 +23,6 @@ class I2SAudioOutput : public IAudioOutput {
   I2SAudioOutput(StreamBufferHandle_t, drivers::IGpios& expander);
   ~I2SAudioOutput();
 
-  auto SetMode(Modes) -> void override;
-
   auto SetMaxVolume(uint16_t) -> void;
   auto SetVolumeDb(uint16_t) -> void;
 
@@ -46,6 +44,9 @@ class I2SAudioOutput : public IAudioOutput {
   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_;
diff --git a/src/audio/include/track_queue.hpp b/src/audio/include/track_queue.hpp
index e4fd7881..5b7c9448 100644
--- a/src/audio/include/track_queue.hpp
+++ b/src/audio/include/track_queue.hpp
@@ -12,6 +12,7 @@
 #include <shared_mutex>
 #include <vector>
 
+#include "audio_events.hpp"
 #include "cppbor_parse.h"
 #include "database.hpp"
 #include "tasks.hpp"
@@ -120,6 +121,8 @@ class TrackQueue {
   TrackQueue& operator=(const TrackQueue&) = delete;
 
  private:
+  auto next(QueueUpdate::Reason r) -> void;
+
   mutable std::shared_mutex mutex_;
 
   tasks::WorkerPool& bg_worker_;