Get basic audio playback going again

src/app_console/app_console.cpp

@@ -200,7 +200,7 @@ void RegisterDbDump() {
   esp_console_cmd_register(&cmd);
 }
 
-AppConsole::AppConsole(std::weak_ptr<database::Database> database)
+AppConsole::AppConsole(const std::weak_ptr<database::Database>& database)
     : database_(database) {
   sInstance = this;
 }
@@ -210,8 +210,8 @@ AppConsole::~AppConsole() {
 
 auto AppConsole::RegisterExtraComponents() -> void {
   RegisterListDir();
-  /*
   RegisterPlayFile();
+  /*
   RegisterToggle();
   RegisterVolume();
   RegisterAudioStatus();

src/app_console/include/app_console.hpp

@@ -15,10 +15,10 @@ namespace console {
 
 class AppConsole : public Console {
  public:
-  explicit AppConsole(std::weak_ptr<database::Database> database);
+  explicit AppConsole(const std::weak_ptr<database::Database>& database);
   virtual ~AppConsole();
 
-  std::weak_ptr<database::Database> database_;
+  const std::weak_ptr<database::Database>& database_;
 
  protected:
   virtual auto RegisterExtraComponents() -> void;

src/audio/audio_decoder.cpp

@@ -14,7 +14,6 @@
 #include <memory>
 #include <variant>
 
-#include "cbor/tinycbor/src/cborinternal_p.h"
 #include "freertos/FreeRTOS.h"
 
 #include "esp_heap_caps.h"
@@ -36,7 +35,8 @@ AudioDecoder::AudioDecoder()
       current_codec_(),
       current_input_format_(),
       current_output_format_(),
-      has_samples_to_send_(false) {}
+      has_samples_to_send_(false),
+      has_input_remaining_(false) {}
 
 AudioDecoder::~AudioDecoder() {}
 
@@ -70,6 +70,10 @@ auto AudioDecoder::ProcessStreamInfo(const StreamInfo& info) -> bool {
   return true;
 }
 
+auto AudioDecoder::NeedsToProcess() const -> bool {
+  return has_samples_to_send_ || has_input_remaining_;
+}
+
 auto AudioDecoder::Process(const std::vector<InputStream>& inputs,
                            OutputStream* output) -> void {
   auto input = inputs.begin();
@@ -124,7 +128,8 @@ auto AudioDecoder::Process(const std::vector<InputStream>& inputs,
       return;
     }
 
-    if (res.value()) {
+    has_input_remaining_ = !res.value();
+    if (!has_input_remaining_) {
       // We're out of useable data in this buffer. Finish immediately; there's
       // nothing to send.
       input->mark_incomplete();

src/audio/audio_fsm.cpp

@@ -29,12 +29,7 @@ auto AudioState::Init(drivers::GpioExpander* gpio_expander,
   sGpioExpander = gpio_expander;
   sDac = dac;
   sDatabase = database;
-}
-
-namespace states {
 
-void Uninitialised::react(const system_fsm::BootComplete&) {
-  transit<Standby>([&]() {
   sFileSource.reset(new FatfsAudioInput());
   sI2SOutput.reset(new I2SAudioOutput(sGpioExpander, sDac));
 
@@ -48,7 +43,12 @@ void Uninitialised::react(const system_fsm::BootComplete&) {
   pipeline->AddInput(sFileSource.get());
 
   task::StartPipeline(pipeline, sI2SOutput.get());
-  });
+}
+
+namespace states {
+
+void Uninitialised::react(const system_fsm::BootComplete&) {
+  transit<Standby>();
 }
 
 void Standby::react(const PlayFile& ev) {

src/audio/audio_task.cpp

@@ -43,20 +43,64 @@ namespace task {
 
 static const char* kTag = "task";
 
+// The default amount of time to wait between pipeline iterations for a single
+// song.
+static constexpr uint_fast16_t kDefaultDelayTicks = pdMS_TO_TICKS(5);
+static constexpr uint_fast16_t kMaxDelayTicks = pdMS_TO_TICKS(10);
+static constexpr uint_fast16_t kMinDelayTicks = pdMS_TO_TICKS(1);
+
 void AudioTaskMain(std::unique_ptr<Pipeline> pipeline, IAudioSink* sink) {
+  // The stream format for bytes currently in the sink buffer.
   std::optional<StreamInfo::Format> output_format;
-  uint_fast16_t delay_ticks = pdMS_TO_TICKS(5);
 
-  std::vector<Pipeline*> elements = pipeline->GetIterationOrder();
+  // How long to wait between pipeline iterations. This is reset for each song,
+  // and readjusted on the fly to maintain a reasonable amount playback buffer.
+  // Buffering too much will mean we process samples inefficiently, wasting CPU
+  // time, whilst buffering too little will affect the quality of the output.
+  uint_fast16_t delay_ticks = kDefaultDelayTicks;
+
+  std::vector<Pipeline*> all_elements = pipeline->GetIterationOrder();
 
   events::EventQueue& event_queue = events::EventQueue::GetInstance();
   while (1) {
-    event_queue.ServiceAudio(delay_ticks);
+    // First, see if we actually have any pipeline work to do in this iteration.
+    bool has_work = false;
+    // We always have work to do if there's still bytes to be sunk.
+    has_work = all_elements.back()->OutStream().info->bytes_in_stream > 0;
+    if (!has_work) {
+      for (Pipeline* p : all_elements) {
+        has_work = p->OutputElement()->NeedsToProcess();
+        if (has_work) {
+          break;
+        }
+      }
+    }
 
-    for (int i = 0; i < elements.size(); i++) {
+    // See if there's any new events.
+    event_queue.ServiceAudio(has_work ? delay_ticks : portMAX_DELAY);
+
+    if (!has_work) {
+      // See if we've been given work by this event.
+      for (Pipeline* p : all_elements) {
+        has_work = p->OutputElement()->NeedsToProcess();
+        if (has_work) {
+          delay_ticks = kDefaultDelayTicks;
+          break;
+        }
+      }
+      if (!has_work) {
+        continue;
+      }
+    }
+
+    // We have work to do! Allow each element in the pipeline to process one
+    // chunk. We iterate from input nodes first, so this should result in
+    // samples in the output buffer.
+
+    for (int i = 0; i < all_elements.size(); i++) {
       std::vector<RawStream> raw_in_streams;
-      elements.at(i)->InStreams(&raw_in_streams);
-      RawStream raw_out_stream = elements.at(i)->OutStream();
+      all_elements.at(i)->InStreams(&raw_in_streams);
+      RawStream raw_out_stream = all_elements.at(i)->OutStream();
 
       // Crop the input and output streams to the ranges that are safe to
       // touch. For the input streams, this is the region that contains
@@ -67,14 +111,14 @@ void AudioTaskMain(std::unique_ptr<Pipeline> pipeline, IAudioSink* sink) {
                     [&](RawStream& s) { in_streams.emplace_back(&s); });
       OutputStream out_stream(&raw_out_stream);
 
-      elements.at(i)->OutputElement()->Process(in_streams, &out_stream);
+      all_elements.at(i)->OutputElement()->Process(in_streams, &out_stream);
     }
 
-    RawStream raw_sink_stream = elements.front()->OutStream();
+    RawStream raw_sink_stream = all_elements.back()->OutStream();
     InputStream sink_stream(&raw_sink_stream);
 
     if (sink_stream.info().bytes_in_stream == 0) {
-      vTaskDelay(pdMS_TO_TICKS(100));
+      // No new bytes to sink, so skip sinking completely.
       continue;
     }
 
@@ -86,24 +130,36 @@ void AudioTaskMain(std::unique_ptr<Pipeline> pipeline, IAudioSink* sink) {
         ESP_LOGI(kTag, "reconfiguring dac");
         output_format = sink_stream.info().format;
         sink->Configure(*output_format);
+      } else {
+        continue;
       }
     }
 
     // We've reconfigured the sink, or it was already configured correctly.
     // Send through some data.
-    if (output_format == sink_stream.info().format &&
-        !std::holds_alternative<std::monostate>(*output_format)) {
-      std::size_t sent =
+    std::size_t bytes_sunk =
         xStreamBufferSend(sink->buffer(), sink_stream.data().data(),
                           sink_stream.data().size_bytes(), 0);
-      if (sent > 0) {
-        ESP_LOGI(
-            kTag, "sunk %u bytes out of %u (%d %%)", sent,
-            sink_stream.info().bytes_in_stream,
-            (int)(((float)sent / (float)sink_stream.info().bytes_in_stream) *
-                  100));
-      }
-      sink_stream.consume(sent);
+
+    // Adjust how long we wait for the next iteration if we're getting too far
+    // ahead or behind.
+    float sunk_percent = static_cast<float>(bytes_sunk) /
+                         static_cast<float>(sink_stream.info().bytes_in_stream);
+
+    if (sunk_percent > 0.66f) {
+      // We're sinking a lot of the output buffer per iteration, so we need to
+      // be running faster.
+      delay_ticks--;
+    } else if (sunk_percent < 0.33f) {
+      // We're not sinking much of the output buffer per iteration, so we can
+      // slow down to save some cycles.
+      delay_ticks++;
+    }
+    delay_ticks = std::clamp(delay_ticks, kMinDelayTicks, kMaxDelayTicks);
+
+    // Finally, actually mark the bytes we sunk as consumed.
+    if (bytes_sunk > 0) {
+      sink_stream.consume(bytes_sunk);
     }
   }
 }

src/audio/fatfs_audio_input.cpp

@@ -51,6 +51,10 @@ auto FatfsAudioInput::OpenFile(const std::string& path) -> bool {
   return true;
 }
 
+auto FatfsAudioInput::NeedsToProcess() const -> bool {
+  return is_file_open_;
+}
+
 auto FatfsAudioInput::Process(const std::vector<InputStream>& inputs,
                               OutputStream* output) -> void {
   if (!is_file_open_) {

src/audio/include/audio_decoder.hpp

@@ -30,6 +30,8 @@ class AudioDecoder : public IAudioElement {
   AudioDecoder();
   ~AudioDecoder();
 
+  auto NeedsToProcess() const -> bool override;
+
   auto Process(const std::vector<InputStream>& inputs, OutputStream* output)
       -> void override;
 
@@ -41,6 +43,7 @@ class AudioDecoder : public IAudioElement {
   std::optional<StreamInfo::Format> current_input_format_;
   std::optional<StreamInfo::Format> current_output_format_;
   bool has_samples_to_send_;
+  bool has_input_remaining_;
 
   auto ProcessStreamInfo(const StreamInfo& info) -> bool;
 };

src/audio/include/audio_element.hpp

@@ -10,6 +10,7 @@
 #include <cstdint>
 #include <deque>
 #include <memory>
+#include <vector>
 
 #include "freertos/FreeRTOS.h"
 
@@ -46,6 +47,8 @@ class IAudioElement {
   IAudioElement() {}
   virtual ~IAudioElement() {}
 
+  virtual auto NeedsToProcess() const -> bool = 0;
+
   virtual auto Process(const std::vector<InputStream>& inputs,
                        OutputStream* output) -> void = 0;
 };

src/audio/include/fatfs_audio_input.hpp

@@ -33,6 +33,8 @@ class FatfsAudioInput : public IAudioElement {
 
   auto OpenFile(const std::string& path) -> bool;
 
+  auto NeedsToProcess() const -> bool override;
+
   auto Process(const std::vector<InputStream>& inputs, OutputStream* output)
       -> void override;
 

src/audio/pipeline.cpp

@@ -5,6 +5,7 @@
  */
 
 #include "pipeline.hpp"
+#include <algorithm>
 #include <memory>
 #include "stream_info.hpp"
 
@@ -53,6 +54,7 @@ auto Pipeline::GetIterationOrder() -> std::vector<Pipeline*> {
     }
   }
 
+  std::reverse(found.begin(), found.end());
   return found;
 }
 

src/drivers/display.cpp

@@ -106,14 +106,12 @@ auto Display::Create(GpioExpander* expander,
   };
   ledc_timer_config(&led_config);
 
-  ledc_channel_config_t led_channel {
-      .gpio_num = kDisplayLedEn,
+  ledc_channel_config_t led_channel{.gpio_num = kDisplayLedEn,
                                     .speed_mode = LEDC_LOW_SPEED_MODE,
                                     .channel = LEDC_CHANNEL_0,
                                     .timer_sel = LEDC_TIMER_0,
                                     .duty = 4095,
-      .hpoint = 0
-  };
+                                    .hpoint = 0};
   ledc_channel_config(&led_channel);
 
   // Next, init the SPI device
@@ -270,13 +268,13 @@ void Display::OnLvglFlush(lv_disp_drv_t* disp_drv,
 
   data[0] = SPI_SWAP_DATA_TX(area_copy.x1, 16);
   data[1] = SPI_SWAP_DATA_TX(area_copy.x2, 16);
-    SendCommandWithData(displays::ST77XX_CASET,
-                        reinterpret_cast<uint8_t*>(data), 4);
+  SendCommandWithData(displays::ST77XX_CASET, reinterpret_cast<uint8_t*>(data),
+                      4);
 
   data[0] = SPI_SWAP_DATA_TX(area_copy.y1, 16);
   data[1] = SPI_SWAP_DATA_TX(area_copy.y2, 16);
-    SendCommandWithData(displays::ST77XX_RASET,
-                        reinterpret_cast<uint8_t*>(data), 4);
+  SendCommandWithData(displays::ST77XX_RASET, reinterpret_cast<uint8_t*>(data),
+                      4);
 
   // Now send the pixels for this region.
   uint32_t size = lv_area_get_width(area) * lv_area_get_height(area);

src/drivers/include/relative_wheel.hpp

@@ -20,7 +20,9 @@ namespace drivers {
 
 class RelativeWheel {
  public:
-  static auto Create(TouchWheel *touch) -> RelativeWheel* { return new RelativeWheel(touch); }
+  static auto Create(TouchWheel* touch) -> RelativeWheel* {
+    return new RelativeWheel(touch);
+  }
 
   explicit RelativeWheel(TouchWheel* touch);
 

src/drivers/relative_wheel.cpp

@@ -74,5 +74,4 @@ auto RelativeWheel::ticks() -> std::int_fast16_t {
   return t;
 }
 
-
 }  // namespace drivers

src/system_fsm/running.cpp

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: GPL-3.0-only
  */
 
+#include "freertos/projdefs.h"
 #include "result.hpp"
 
 #include "audio_fsm.hpp"
@@ -24,6 +25,7 @@ static const char kTag[] = "RUN";
  */
 void Running::entry() {
   ESP_LOGI(kTag, "mounting sd card");
+  vTaskDelay(pdMS_TO_TICKS(250));
   auto storage_res = drivers::SdStorage::Create(sGpioExpander.get());
   if (storage_res.has_error()) {
     events::Dispatch<StorageError, SystemState, audio::AudioState, ui::UiState>(
@@ -31,6 +33,7 @@ void Running::entry() {
     return;
   }
   sStorage.reset(storage_res.value());
+  vTaskDelay(pdMS_TO_TICKS(250));
 
   ESP_LOGI(kTag, "opening database");
   auto database_res = database::Database::Open();

src/ui/ui_fsm.cpp

@@ -28,12 +28,14 @@ auto UiState::Init(drivers::GpioExpander* gpio_expander,
   sGpioExpander = gpio_expander;
   sTouchWheel = touchwheel;
   sDisplay = display;
+
+  StartLvgl(sTouchWheel, sDisplay);
 }
 
 namespace states {
 
 void PreBoot::react(const system_fsm::DisplayReady& ev) {
-  transit<Splash>([&]() { StartLvgl(sTouchWheel, sDisplay); });
+  transit<Splash>();
 }
 
 void Splash::entry() {

src/ui/wheel_encoder.cpp

@@ -10,11 +10,14 @@
 namespace ui {
 
 void encoder_read(lv_indev_drv_t* drv, lv_indev_data_t* data) {
-  TouchWheelEncoder *instance = reinterpret_cast<TouchWheelEncoder*>(drv->user_data);
+  TouchWheelEncoder* instance =
+      reinterpret_cast<TouchWheelEncoder*>(drv->user_data);
   instance->Read(data);
 }
 
-  TouchWheelEncoder::TouchWheelEncoder(std::weak_ptr<drivers::RelativeWheel> wheel) : wheel_(wheel) {
+TouchWheelEncoder::TouchWheelEncoder(
+    std::weak_ptr<drivers::RelativeWheel> wheel)
+    : wheel_(wheel) {
   lv_indev_drv_init(&driver_);
   driver_.type = LV_INDEV_TYPE_ENCODER;
   driver_.read_cb = encoder_read;
@@ -32,7 +35,8 @@ auto TouchWheelEncoder::Read(lv_indev_data_t *data) -> void {
   }
 
   lock->Update();
-  data->state = lock->is_pressed() ? LV_INDEV_STATE_PRESSED : LV_INDEV_STATE_RELEASED;
+  data->state =
+      lock->is_pressed() ? LV_INDEV_STATE_PRESSED : LV_INDEV_STATE_RELEASED;
   data->enc_diff = lock->ticks();
 }