Mostly working pipeline, including proper EOF signalling

14 files changed, 177 insertions, 19 deletions

diff --git a/src/audio/audio_decoder.cpp b/src/audio/audio_decoder.cpp
index 27b9cca3..d90ca496 100644
--- a/src/audio/audio_decoder.cpp
+++ b/src/audio/audio_decoder.cpp
@@ -84,6 +84,16 @@ auto AudioDecoder::ProcessChunk(const cpp::span<std::byte>& chunk)
   return {};
 }
 
+auto AudioDecoder::ProcessEndOfStream() -> void {
+  has_samples_to_send_ = false;
+  needs_more_input_ = true;
+  current_codec_.reset();
+
+  SendOrBufferEvent(
+      std::unique_ptr<StreamEvent>(
+        StreamEvent::CreateEndOfStream(input_events_)));
+}
+
 auto AudioDecoder::Process() -> cpp::result<void, AudioProcessingError> {
   if (has_samples_to_send_) {
     ESP_LOGI(kTag, "sending samples");
@@ -132,7 +142,7 @@ auto AudioDecoder::Process() -> cpp::result<void, AudioProcessingError> {
     has_samples_to_send_ = true;
 
     if (needs_more_input_) {
-      chunk_reader_->HandleLeftovers(current_codec_->GetInputPosition());
+      chunk_reader_->HandleBytesUsed(current_codec_->GetInputPosition());
     }
   }
 
diff --git a/src/audio/audio_playback.cpp b/src/audio/audio_playback.cpp
index 4df598c5..504a2a4e 100644
--- a/src/audio/audio_playback.cpp
+++ b/src/audio/audio_playback.cpp
@@ -38,9 +38,9 @@ auto AudioPlayback::create(drivers::GpioExpander* expander,
   playback->ConnectElements(codec.get(), sink.get());
 
   // Launch!
-  playback->element_handles_.push_back(StartAudioTask("src", source));
-  playback->element_handles_.push_back(StartAudioTask("dec", codec));
-  playback->element_handles_.push_back(StartAudioTask("sink", sink));
+  playback->element_handles_.push_back(StartAudioTask("src", {}, source));
+  playback->element_handles_.push_back(StartAudioTask("dec", {}, codec));
+  playback->element_handles_.push_back(StartAudioTask("sink", 0, sink));
 
   playback->input_handle_ = source->InputEventQueue();
 
@@ -60,6 +60,8 @@ auto AudioPlayback::Play(const std::string& filename) -> void {
   info.path = filename;
   auto event = StreamEvent::CreateStreamInfo(input_handle_, info);
   xQueueSend(input_handle_, &event, portMAX_DELAY);
+  event = StreamEvent::CreateEndOfStream(input_handle_);
+  xQueueSend(input_handle_, &event, portMAX_DELAY);
 }
 
 auto AudioPlayback::ConnectElements(IAudioElement* src, IAudioElement* sink)
diff --git a/src/audio/audio_task.cpp b/src/audio/audio_task.cpp
index 47b115cc..078aa461 100644
--- a/src/audio/audio_task.cpp
+++ b/src/audio/audio_task.cpp
@@ -28,6 +28,7 @@ namespace audio {
 static const char* kTag = "task";
 
 auto StartAudioTask(const std::string& name,
+                    std::optional<BaseType_t> core_id,
                     std::shared_ptr<IAudioElement> element)
     -> std::unique_ptr<AudioElementHandle> {
   auto task_handle = std::make_unique<TaskHandle_t>();
@@ -36,8 +37,13 @@ auto StartAudioTask(const std::string& name,
   AudioTaskArgs* args = new AudioTaskArgs{.element = element};
 
   ESP_LOGI(kTag, "starting audio task %s", name.c_str());
-  xTaskCreate(&AudioTaskMain, name.c_str(), element->StackSizeBytes(), args,
-              kTaskPriorityAudio, task_handle.get());
+  if (core_id) {
+    xTaskCreatePinnedToCore(&AudioTaskMain, name.c_str(), element->StackSizeBytes(), args,
+                kTaskPriorityAudio, task_handle.get(), *core_id);
+  } else {
+    xTaskCreate(&AudioTaskMain, name.c_str(), element->StackSizeBytes(), args,
+                kTaskPriorityAudio, task_handle.get());
+  }
 
   return std::make_unique<AudioElementHandle>(std::move(task_handle), element);
 }
diff --git a/src/audio/chunk.cpp b/src/audio/chunk.cpp
index 61c0dc2b..01760a84 100644
--- a/src/audio/chunk.cpp
+++ b/src/audio/chunk.cpp
@@ -41,8 +41,11 @@ auto ChunkReader::HandleNewData(cpp::span<std::byte> data)
   return last_data_in_working_buffer_;
 }
 
-auto ChunkReader::HandleLeftovers(std::size_t bytes_used) -> void {
-  leftover_bytes_ = last_data_in_working_buffer_.size() - bytes_used;
+auto ChunkReader::HandleBytesUsed(std::size_t bytes_used) -> void {
+  HandleBytesLeftOver(last_data_in_working_buffer_.size() - bytes_used);
+}
+auto ChunkReader::HandleBytesLeftOver(std::size_t bytes_left) -> void {
+  leftover_bytes_ = bytes_left;
 
   // Ensure that we don't have more than a chunk of leftever bytes. This is
   // bad, because we probably won't have enough data to store the next chunk.
@@ -55,4 +58,8 @@ auto ChunkReader::HandleLeftovers(std::size_t bytes_used) -> void {
   }
 }
 
+auto ChunkReader::GetLeftovers() -> cpp::span<std::byte> {
+  return working_buffer_.first(leftover_bytes_);
+}
+
 }  // namespace audio
diff --git a/src/audio/fatfs_audio_input.cpp b/src/audio/fatfs_audio_input.cpp
index 08f39347..8990bf4f 100644
--- a/src/audio/fatfs_audio_input.cpp
+++ b/src/audio/fatfs_audio_input.cpp
@@ -69,6 +69,16 @@ auto FatfsAudioInput::ProcessChunk(const cpp::span<std::byte>& chunk)
   return cpp::fail(UNSUPPORTED_STREAM);
 }
 
+auto FatfsAudioInput::ProcessEndOfStream() -> void {
+  if (is_file_open_) {
+      f_close(&current_file_);
+      is_file_open_ = false;
+      SendOrBufferEvent(
+          std::unique_ptr<StreamEvent>(
+            StreamEvent::CreateEndOfStream(input_events_)));
+  }
+}
+
 auto FatfsAudioInput::Process() -> cpp::result<void, AudioProcessingError> {
   if (is_file_open_) {
     auto dest_event = std::unique_ptr<StreamEvent>(
diff --git a/src/audio/i2s_audio_output.cpp b/src/audio/i2s_audio_output.cpp
index b00e31d3..3bed15b5 100644
--- a/src/audio/i2s_audio_output.cpp
+++ b/src/audio/i2s_audio_output.cpp
@@ -7,6 +7,7 @@
 
 #include "audio_element.hpp"
 #include "dac.hpp"
+#include "freertos/projdefs.h"
 #include "gpio_expander.hpp"
 #include "result.hpp"
 
@@ -15,6 +16,8 @@ static const char* kTag = "I2SOUT";
 
 namespace audio {
 
+static const std::size_t kDmaQueueLength = 8;
+
 auto I2SAudioOutput::create(drivers::GpioExpander* expander)
     -> cpp::result<std::shared_ptr<I2SAudioOutput>, Error> {
   // First, we need to perform initial configuration of the DAC chip.
@@ -38,12 +41,26 @@ I2SAudioOutput::I2SAudioOutput(drivers::GpioExpander* expander,
     : expander_(expander),
       dac_(std::move(dac)),
       volume_(255),
-      is_soft_muted_(false) {}
+      is_soft_muted_(false),
+      chunk_reader_(),
+      latest_chunk_(),
+      dma_size_(),
+      dma_queue_(nullptr) {}
 
 I2SAudioOutput::~I2SAudioOutput() {
+  if (dma_queue_ != nullptr) {
+    ClearDmaQueue();
+  }
   // TODO: power down the DAC.
 }
 
+auto I2SAudioOutput::HasUnprocessedInput() -> bool {
+  if (dma_queue_ == nullptr || !dma_size_) {
+    return false;
+  }
+  return latest_chunk_.size() >= *dma_size_;
+}
+
 auto I2SAudioOutput::ProcessStreamInfo(const StreamInfo& info)
     -> cpp::result<void, AudioProcessingError> {
   // TODO(jacqueline): probs do something with the channel hey
@@ -53,6 +70,12 @@ auto I2SAudioOutput::ProcessStreamInfo(const StreamInfo& info)
     return cpp::fail(UNSUPPORTED_STREAM);
   }
 
+  if (!info.chunk_size) {
+    ESP_LOGE(kTag, "audio stream missing chunk size");
+    return cpp::fail(UNSUPPORTED_STREAM);
+  }
+  chunk_reader_.emplace(*info.chunk_size);
+
   ESP_LOGI(kTag, "incoming audio stream: %u bpp @ %u Hz", *info.bits_per_sample,
            *info.sample_rate);
 
@@ -85,23 +108,78 @@ auto I2SAudioOutput::ProcessStreamInfo(const StreamInfo& info)
       return cpp::fail(UNSUPPORTED_STREAM);
   }
 
-  dac_->Reconfigure(bps, sample_rate);
+  QueueHandle_t new_dma_queue =
+      xQueueCreate(kDmaQueueLength, sizeof(std::byte*));
+
+  dma_size_ = dac_->Reconfigure(bps, sample_rate, new_dma_queue);
+
+  if (dma_queue_ != nullptr) {
+    ClearDmaQueue();
+  }
+  dma_queue_ = new_dma_queue;
 
   return {};
 }
 
 auto I2SAudioOutput::ProcessChunk(const cpp::span<std::byte>& chunk)
     -> cpp::result<std::size_t, AudioProcessingError> {
-  ESP_LOGI(kTag, "playing samples");
-  SetSoftMute(false);
-  // TODO(jacqueline): write smaller parts with a small delay so that we can
-  // be responsive to pause and seek commands.
-  dac_->WriteData(chunk, portMAX_DELAY);
+  ESP_LOGI(kTag, "received new samples");
+  latest_chunk_ = chunk_reader_->HandleNewData(chunk);
   return 0;
 }
 
+auto I2SAudioOutput::ProcessEndOfStream() -> void {
+  if (chunk_reader_ && dma_size_) {
+    auto leftovers = chunk_reader_->GetLeftovers();
+    if (leftovers.size() > 0 && leftovers.size() < *dma_size_) {
+      std::byte* dest = static_cast<std::byte*>(malloc(*dma_size_));
+      cpp::span dest_span(dest, *dma_size_);
+
+      std::copy(leftovers.begin(), leftovers.end(), dest_span.begin());
+      std::fill(dest_span.begin() + leftovers.size(), dest_span.end(), static_cast<std::byte>(0));
+
+      xQueueSend(dma_queue_, &dest, portMAX_DELAY);
+    }
+  }
+
+  SendOrBufferEvent(
+      std::unique_ptr<StreamEvent>(
+        StreamEvent::CreateEndOfStream(input_events_)));
+
+  chunk_reader_.reset();
+  dma_size_.reset();
+}
+
 auto I2SAudioOutput::Process() -> cpp::result<void, AudioProcessingError> {
-  // TODO(jacqueline): Play the stream in smaller sections
+  std::size_t spaces_available = uxQueueSpacesAvailable(dma_queue_);
+  if (spaces_available == 0) {
+    // TODO: think about this more. can this just be the output event queue?
+    vTaskDelay(pdMS_TO_TICKS(100));
+    return {};
+  }
+
+  // Fill the queue as much as possible, since we need to be able to stream
+  // FAST.
+  while (latest_chunk_.size() >= *dma_size_ && spaces_available > 0) {
+    // TODO: small memory arena for this?
+    std::byte* dest = static_cast<std::byte*>(malloc(*dma_size_));
+    cpp::span dest_span(dest, *dma_size_);
+    cpp::span src_span = latest_chunk_.first(*dma_size_);
+    std::copy(src_span.begin(), src_span.end(), dest_span.begin());
+    if (!xQueueSend(dma_queue_, &dest, 0)) {
+      // TODO: calculate how often we expect this to happen.
+      free(dest);
+      break;
+    }
+    latest_chunk_ = latest_chunk_.subspan(*dma_size_);
+    ESP_LOGI(kTag, "wrote dma buffer of size %u", *dma_size_);
+  }
+  if (latest_chunk_.size() < *dma_size_) {
+    // TODO: if this is the end of the stream, then we should be sending this
+    // with zero padding. hmm. i guess we need an explicit EOF event?
+    chunk_reader_->HandleBytesLeftOver(latest_chunk_.size());
+    ESP_LOGI(kTag, "not enough samples for dma buffer");
+  }
   return {};
 }
 
@@ -124,4 +202,17 @@ auto I2SAudioOutput::SetSoftMute(bool enabled) -> void {
   }
 }
 
+auto I2SAudioOutput::ClearDmaQueue() -> void {
+  // Ensure we don't leak any memory from events leftover in the queue.
+  while (uxQueueSpacesAvailable(dma_queue_) < kDmaQueueLength) {
+    std::byte* data = nullptr;
+    if (xQueueReceive(input_events_, &data, 0)) {
+      free(data);
+    } else {
+      break;
+    }
+  }
+  vQueueDelete(dma_queue_);
+}
+
 }  // namespace audio
diff --git a/src/audio/include/audio_decoder.hpp b/src/audio/include/audio_decoder.hpp
index d0f7469b..aa83825f 100644
--- a/src/audio/include/audio_decoder.hpp
+++ b/src/audio/include/audio_decoder.hpp
@@ -37,6 +37,7 @@ class AudioDecoder : public IAudioElement {
       -> cpp::result<void, AudioProcessingError> override;
   auto ProcessChunk(const cpp::span<std::byte>& chunk)
       -> cpp::result<std::size_t, AudioProcessingError> override;
+  auto ProcessEndOfStream() -> void override;
   auto Process() -> cpp::result<void, AudioProcessingError> override;
 
   AudioDecoder(const AudioDecoder&) = delete;
diff --git a/src/audio/include/audio_element.hpp b/src/audio/include/audio_element.hpp
index c6453d4d..0c80524c 100644
--- a/src/audio/include/audio_element.hpp
+++ b/src/audio/include/audio_element.hpp
@@ -105,6 +105,8 @@ class IAudioElement {
   virtual auto ProcessChunk(const cpp::span<std::byte>& chunk)
       -> cpp::result<std::size_t, AudioProcessingError> = 0;
 
+  virtual auto ProcessEndOfStream() -> void = 0;
+
   /*
    * Called when there has been no data received over the input buffer for some
    * time. This could be used to synthesize output, or to save memory by
diff --git a/src/audio/include/audio_task.hpp b/src/audio/include/audio_task.hpp
index 9a76ea7e..399ad679 100644
--- a/src/audio/include/audio_task.hpp
+++ b/src/audio/include/audio_task.hpp
@@ -1,9 +1,12 @@
 #pragma once
 
 #include <memory>
+#include <string>
+#include <optional>
 
 #include "audio_element.hpp"
 #include "audio_element_handle.hpp"
+#include "freertos/portmacro.h"
 
 namespace audio {
 
@@ -12,6 +15,7 @@ struct AudioTaskArgs {
 };
 
 auto StartAudioTask(const std::string& name,
+                    std::optional<BaseType_t> core_id,
                     std::shared_ptr<IAudioElement> element)
     -> std::unique_ptr<AudioElementHandle>;
 
diff --git a/src/audio/include/chunk.hpp b/src/audio/include/chunk.hpp
index 0ece1ed6..31e1f969 100644
--- a/src/audio/include/chunk.hpp
+++ b/src/audio/include/chunk.hpp
@@ -27,7 +27,8 @@ class ChunkReader {
   explicit ChunkReader(std::size_t chunk_size);
   ~ChunkReader();
 
-  auto HandleLeftovers(std::size_t bytes_used) -> void;
+  auto HandleBytesLeftOver(std::size_t bytes_left) -> void;
+  auto HandleBytesUsed(std::size_t bytes_used) -> void;
 
   /*
    * Reads chunks of data from the given input stream, and invokes the given
@@ -43,6 +44,8 @@ class ChunkReader {
    */
   auto HandleNewData(cpp::span<std::byte> data) -> cpp::span<std::byte>;
 
+  auto GetLeftovers() -> cpp::span<std::byte>;
+
   ChunkReader(const ChunkReader&) = delete;
   ChunkReader& operator=(const ChunkReader&) = delete;
 
diff --git a/src/audio/include/fatfs_audio_input.hpp b/src/audio/include/fatfs_audio_input.hpp
index 5625d941..883441c2 100644
--- a/src/audio/include/fatfs_audio_input.hpp
+++ b/src/audio/include/fatfs_audio_input.hpp
@@ -28,6 +28,7 @@ class FatfsAudioInput : public IAudioElement {
       -> cpp::result<void, AudioProcessingError> override;
   auto ProcessChunk(const cpp::span<std::byte>& chunk)
       -> cpp::result<std::size_t, AudioProcessingError> override;
+  auto ProcessEndOfStream() -> void override;
   auto Process() -> cpp::result<void, AudioProcessingError> override;
 
   FatfsAudioInput(const FatfsAudioInput&) = delete;
diff --git a/src/audio/include/i2s_audio_output.hpp b/src/audio/include/i2s_audio_output.hpp
index 02ac7a16..b4fd4c59 100644
--- a/src/audio/include/i2s_audio_output.hpp
+++ b/src/audio/include/i2s_audio_output.hpp
@@ -4,6 +4,7 @@
 #include <memory>
 
 #include "audio_element.hpp"
+#include "chunk.hpp"
 #include "result.hpp"
 
 #include "dac.hpp"
@@ -21,13 +22,13 @@ class I2SAudioOutput : public IAudioElement {
                  std::unique_ptr<drivers::AudioDac> dac);
   ~I2SAudioOutput();
 
-  // TODO.
-  auto HasUnprocessedInput() -> bool override { return false; }
+  auto HasUnprocessedInput() -> bool override;
 
   auto ProcessStreamInfo(const StreamInfo& info)
       -> cpp::result<void, AudioProcessingError> override;
   auto ProcessChunk(const cpp::span<std::byte>& chunk)
       -> cpp::result<std::size_t, AudioProcessingError> override;
+  auto ProcessEndOfStream() -> void override;
   auto Process() -> cpp::result<void, AudioProcessingError> override;
 
   I2SAudioOutput(const I2SAudioOutput&) = delete;
@@ -37,11 +38,18 @@ class I2SAudioOutput : public IAudioElement {
   auto SetVolume(uint8_t volume) -> void;
   auto SetSoftMute(bool enabled) -> void;
 
+  auto ClearDmaQueue() -> void;
+
   drivers::GpioExpander* expander_;
   std::unique_ptr<drivers::AudioDac> dac_;
 
   uint8_t volume_;
   bool is_soft_muted_;
+
+  std::optional<ChunkReader> chunk_reader_;
+  cpp::span<std::byte> latest_chunk_;
+  std::optional<std::size_t> dma_size_;
+  QueueHandle_t dma_queue_;
 };
 
 }  // namespace audio
diff --git a/src/audio/include/stream_event.hpp b/src/audio/include/stream_event.hpp
index 4f441fa5..e84c8388 100644
--- a/src/audio/include/stream_event.hpp
+++ b/src/audio/include/stream_event.hpp
@@ -16,6 +16,7 @@ struct StreamEvent {
   static auto CreateChunkData(QueueHandle_t source, std::size_t chunk_size)
       -> StreamEvent*;
   static auto CreateChunkNotification(QueueHandle_t source) -> StreamEvent*;
+  static auto CreateEndOfStream(QueueHandle_t source) -> StreamEvent*;
 
   StreamEvent();
   ~StreamEvent();
@@ -28,6 +29,7 @@ struct StreamEvent {
     STREAM_INFO,
     CHUNK_DATA,
     CHUNK_NOTIFICATION,
+    END_OF_STREAM,
   } tag;
 
   union {
diff --git a/src/audio/stream_event.cpp b/src/audio/stream_event.cpp
index e3228680..6efebbca 100644
--- a/src/audio/stream_event.cpp
+++ b/src/audio/stream_event.cpp
@@ -37,6 +37,13 @@ auto StreamEvent::CreateChunkNotification(QueueHandle_t source)
   return event;
 }
 
+auto StreamEvent::CreateEndOfStream(QueueHandle_t source) -> StreamEvent* {
+  auto event = new StreamEvent;
+  event->tag = StreamEvent::END_OF_STREAM;
+  event->source = source;
+  return event;
+}
+
 StreamEvent::StreamEvent() : tag(StreamEvent::UNINITIALISED) {}
 
 StreamEvent::~StreamEvent() {
@@ -51,6 +58,8 @@ StreamEvent::~StreamEvent() {
       break;
     case CHUNK_NOTIFICATION:
       break;
+    case END_OF_STREAM:
+      break;
   }
 }
 
@@ -70,6 +79,8 @@ StreamEvent::StreamEvent(StreamEvent&& other) {
       break;
     case CHUNK_NOTIFICATION:
       break;
+    case END_OF_STREAM:
+      break;
   }
   other.tag = StreamEvent::UNINITIALISED;
 }