1 files changed, 65 insertions, 76 deletions

diff --git a/src/audio/audio_decoder.cpp b/src/audio/audio_decoder.cpp
index 9879b042..4b9826a9 100644
--- a/src/audio/audio_decoder.cpp
+++ b/src/audio/audio_decoder.cpp
@@ -2,13 +2,17 @@
 
 #include <string.h>
 
+#include <algorithm>
 #include <cstddef>
 #include <cstdint>
 #include <memory>
+#include <variant>
 
+#include "cbor/tinycbor/src/cborinternal_p.h"
 #include "freertos/FreeRTOS.h"
 
 #include "esp_heap_caps.h"
+#include "esp_log.h"
 #include "freertos/message_buffer.h"
 #include "freertos/portmacro.h"
 
@@ -21,128 +25,113 @@ namespace audio {
 
 static const char* kTag = "DEC";
 
-static const std::size_t kChunkSize = 1024;
-static const std::size_t kReadahead = 8;
-
 AudioDecoder::AudioDecoder()
     : IAudioElement(),
-      arena_(kChunkSize, kReadahead, MALLOC_CAP_SPIRAM),
-      stream_info_({}),
-      has_samples_to_send_(false),
-      needs_more_input_(true) {}
+      current_codec_(),
+      current_input_format_(),
+      current_output_format_(),
+      has_samples_to_send_(false) {}
 
 AudioDecoder::~AudioDecoder() {}
 
-auto AudioDecoder::HasUnprocessedInput() -> bool {
-  return !needs_more_input_ || has_samples_to_send_;
-}
-
-auto AudioDecoder::IsOverBuffered() -> bool {
-  return arena_.BlocksFree() == 0;
-}
-
-auto AudioDecoder::ProcessStreamInfo(const StreamInfo& info) -> void {
-  stream_info_ = info;
-
-  if (info.chunk_size) {
-    chunk_reader_.emplace(info.chunk_size.value());
-  } else {
-    ESP_LOGE(kTag, "no chunk size given");
-    return;
+auto AudioDecoder::ProcessStreamInfo(const StreamInfo& info) -> bool {
+  if (!std::holds_alternative<StreamInfo::Encoded>(info.format)) {
+    return false;
   }
+  ESP_LOGI(kTag, "got new stream");
+  const auto& encoded = std::get<StreamInfo::Encoded>(info.format);
 
   // Reuse the existing codec if we can. This will help with gapless playback,
   // since we can potentially just continue to decode as we were before,
   // without any setup overhead.
   if (current_codec_ != nullptr &&
-      current_codec_->CanHandleFile(info.path.value_or(""))) {
+      current_codec_->CanHandleType(encoded.type)) {
     current_codec_->ResetForNewStream();
-    return;
+    ESP_LOGI(kTag, "reusing existing decoder");
+    return true;
   }
 
-  auto result = codecs::CreateCodecForFile(info.path.value_or(""));
+  // TODO: use audio type from stream
+  auto result = codecs::CreateCodecForType(encoded.type);
   if (result.has_value()) {
+    ESP_LOGI(kTag, "creating new decoder");
     current_codec_ = std::move(result.value());
   } else {
     ESP_LOGE(kTag, "no codec for this file");
-    return;
+    return false;
   }
 
-  stream_info_ = info;
-  has_sent_stream_info_ = false;
+  return true;
 }
 
-auto AudioDecoder::ProcessChunk(const cpp::span<std::byte>& chunk) -> void {
-  if (current_codec_ == nullptr || !chunk_reader_) {
-    // Should never happen, but fail explicitly anyway.
-    ESP_LOGW(kTag, "received chunk without chunk size or codec");
+auto AudioDecoder::Process(const std::vector<InputStream>& inputs,
+                           OutputStream* output) -> void {
+  auto input = inputs.begin();
+  const StreamInfo& info = input->info();
+  if (std::holds_alternative<std::monostate>(info.format) ||
+      info.bytes_in_stream == 0) {
+    // TODO(jacqueline): should we clear the stream format?
+    // output->prepare({});
     return;
   }
 
-  ESP_LOGI(kTag, "received new chunk (size %u)", chunk.size());
-  current_codec_->SetInput(chunk_reader_->HandleNewData(chunk));
-  needs_more_input_ = false;
-}
+  if (!current_input_format_ || *current_input_format_ != info.format) {
+    // The input stream has changed! Immediately throw everything away and
+    // start from scratch.
+    current_input_format_ = info.format;
+    has_samples_to_send_ = false;
 
-auto AudioDecoder::ProcessEndOfStream() -> void {
-  has_samples_to_send_ = false;
-  needs_more_input_ = true;
-  current_codec_.reset();
+    ProcessStreamInfo(info);
+  }
 
-  SendOrBufferEvent(std::unique_ptr<StreamEvent>(
-      StreamEvent::CreateEndOfStream(input_events_)));
-}
+  current_codec_->SetInput(input->data());
 
-auto AudioDecoder::Process() -> void {
-  if (has_samples_to_send_) {
-    // Writing samples is relatively quick (it's just a bunch of memcopy's), so
-    // do them all at once.
-    while (has_samples_to_send_ && !IsOverBuffered()) {
-      if (!has_sent_stream_info_) {
-        has_sent_stream_info_ = true;
+  while (true) {
+    if (has_samples_to_send_) {
+      if (!current_output_format_) {
         auto format = current_codec_->GetOutputFormat();
-        stream_info_->bits_per_sample = format.bits_per_sample;
-        stream_info_->sample_rate = format.sample_rate_hz;
-        stream_info_->channels = format.num_channels;
-        stream_info_->chunk_size = kChunkSize;
-
-        auto event =
-            StreamEvent::CreateStreamInfo(input_events_, *stream_info_);
-        SendOrBufferEvent(std::unique_ptr<StreamEvent>(event));
+        current_output_format_ = StreamInfo::Pcm{
+            .channels = format.num_channels,
+            .bits_per_sample = format.bits_per_sample,
+            .sample_rate = format.sample_rate_hz,
+        };
       }
 
-      auto block = arena_.Acquire();
-      if (!block) {
-        return;
+      if (!output->prepare(*current_output_format_)) {
+        break;
       }
 
-      auto write_res =
-          current_codec_->WriteOutputSamples({block->start, block->size});
-      block->used_size = write_res.first;
+      auto write_res = current_codec_->WriteOutputSamples(output->data());
+      output->add(write_res.first);
       has_samples_to_send_ = !write_res.second;
 
-      auto chunk = std::unique_ptr<StreamEvent>(
-          StreamEvent::CreateArenaChunk(input_events_, *block));
-      if (!SendOrBufferEvent(std::move(chunk))) {
-        return;
+      if (has_samples_to_send_) {
+        // We weren't able to fit all the generated samples into the output
+        // buffer. Stop trying; we'll finish up during the next pass.
+        break;
       }
     }
-    // We will process the next frame during the next call to this method.
-  }
 
-  if (!needs_more_input_) {
     auto res = current_codec_->ProcessNextFrame();
     if (res.has_error()) {
       // TODO(jacqueline): Handle errors.
       return;
     }
-    needs_more_input_ = res.value();
-    has_samples_to_send_ = true;
 
-    if (needs_more_input_) {
-      chunk_reader_->HandleBytesUsed(current_codec_->GetInputPosition());
+    if (res.value()) {
+      // We're out of useable data in this buffer. Finish immediately; there's
+      // nothing to send.
+      input->mark_incomplete();
+      break;
+    } else {
+      has_samples_to_send_ = true;
     }
   }
+
+  std::size_t pos = current_codec_->GetInputPosition();
+  if (pos > 0) {
+    input->consume(pos - 1);
+  }
 }
 
 }  // namespace audio