Rename the main audio tasks to be more sensible

1 files changed, 73 insertions, 0 deletions

diff --git a/src/audio/include/audio_decoder.hpp b/src/audio/include/audio_decoder.hpp
new file mode 100644
index 00000000..1759f6e4
--- /dev/null
+++ b/src/audio/include/audio_decoder.hpp
@@ -0,0 +1,73 @@
+/*
+ * 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_sink.hpp"
+#include "audio_source.hpp"
+#include "codec.hpp"
+#include "track.hpp"
+#include "types.hpp"
+
+namespace audio {
+
+/*
+ * Sample-based timer for the current elapsed playback time.
+ */
+class Timer {
+ public:
+  Timer(const codecs::ICodec::OutputFormat& format);
+
+  auto AddSamples(std::size_t) -> void;
+
+ private:
+  uint32_t current_seconds_;
+  uint32_t current_sample_in_second_;
+  uint32_t samples_per_second_;
+
+  uint32_t total_duration_seconds_;
+};
+
+/*
+ * 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<codecs::IStream>) -> 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::unique_ptr<Timer> timer_;
+
+  std::optional<codecs::ICodec::OutputFormat> current_format_;
+  std::optional<IAudioOutput::Format> current_sink_format_;
+
+  cpp::span<sample::Sample> codec_buffer_;
+};
+
+}  // namespace audio