Reorganize emu folder, update S-SMP system infra

src/app/emu/audio/apu.cc

@@ -0,0 +1,125 @@
+#include "app/emu/audio/apu.h"
+
+#include <cstdint>
+#include <functional>
+#include <iostream>
+#include <vector>
+
+#include "app/emu/audio/dsp.h"
+#include "app/emu/audio/spc700.h"
+#include "app/emu/clock.h"
+#include "app/emu/mem.h"
+
+namespace yaze {
+namespace app {
+namespace emu {
+
+void APU::Init() {
+  // Set the clock frequency
+  clock_.SetFrequency(kApuClockSpeed);
+
+  // Initialize Digital Signal Processor Callbacks
+  dsp_.SetSampleFetcher([this](uint16_t address) -> uint8_t {
+    return this->FetchSampleFromRam(address);
+  });
+
+  dsp_.SetSamplePusher(
+      [this](int16_t sample) { this->PushToAudioBuffer(sample); });
+
+  // Initialize registers
+  // ...
+}
+
+void APU::Reset() {
+  // Reset the clock
+  clock_.ResetAccumulatedTime();
+
+  // Reset the SPC700
+  // ...
+}
+
+void APU::Update() {
+  auto cycles_to_run = clock_.GetCycleCount();
+
+  for (auto i = 0; i < cycles_to_run; ++i) {
+    // Update the APU
+    // ...
+
+    // Update the SPC700
+    // ...
+  }
+}
+
+void APU::ProcessSamples() {
+  // Fetch sample data from AudioRam
+  // Iterate over all voices
+  for (uint8_t voice_num = 0; voice_num < 8; voice_num++) {
+    // Fetch the sample data for the current voice from AudioRam
+    uint8_t sample = FetchSampleForVoice(voice_num);
+
+    // Process the sample through DSP
+    int16_t processed_sample = dsp_.ProcessSample(voice_num, sample);
+
+    // Add the processed sample to the audio buffer
+    audioSamples_.push_back(processed_sample);
+  }
+}
+
+uint8_t APU::FetchSampleForVoice(uint8_t voice_num) {
+  // Define how you determine the address based on the voice_num
+  uint16_t address = CalculateAddressForVoice(voice_num);
+  return aram_.read(address);
+}
+
+uint16_t APU::CalculateAddressForVoice(uint8_t voice_num) {
+  // Placeholder logic to calculate the address in the AudioRam
+  // based on the voice number.
+  return voice_num;  // Assuming each voice has a fixed size
+}
+
+int16_t APU::GetNextSample() {
+  // This method fetches the next sample. If there's no sample available, it can
+  // return 0 or the last sample.
+  if (!audioSamples_.empty()) {
+    int16_t sample = audioSamples_.front();
+    audioSamples_.erase(audioSamples_.begin());
+    return sample;
+  }
+  return 0;  // or return the last sample
+}
+
+uint8_t APU::ReadRegister(uint16_t address) {
+  // ...
+}
+
+void APU::WriteRegister(uint16_t address, uint8_t value) {
+  // ...
+}
+
+const std::vector<int16_t>& APU::GetAudioSamples() const {
+  // ...
+}
+
+void APU::UpdateChannelSettings() {
+  // ...
+}
+
+int16_t APU::GenerateSample(int channel) {
+  // ...
+}
+
+void APU::ApplyEnvelope(int channel) {
+  // ...
+}
+
+uint8_t APU::ReadDSPMemory(uint16_t address) {
+  // ...
+}
+
+void APU::WriteDSPMemory(uint16_t address, uint8_t value) {
+  // ...
+}
+
+}  // namespace emu
+}  // namespace app
+}  // namespace yaze