AudioRecorder.hpp

#pragma once
#include <ossia/audio/drwav_write_handle.hpp>
#include <ossia/network/value/detail/value_conversion_impl.hpp>
 
#include <QDateTime>
 
#include <AvndProcesses/AddressTools.hpp>
#include <halp/audio.hpp>
#include <halp/callback.hpp>
 
namespace avnd_tools
{
struct AudioRecorder
{
  halp_meta(name, "Audio recorder")
  halp_meta(author, "ossia team")
  halp_meta(category, "Audio/Recording")
  halp_meta(description, "Records audio to a file")
  halp_meta(c_name, "avnd_audio_recorder")
  halp_meta(uuid, "4463dddc-6acf-4106-a680-fed67d8030da")
 
  using audio_buffer = boost::container::vector<double>;
 
  // Threaded worker
  struct recorder_thread
  {
    ossia::drwav_write_handle f;
    std::string filename;
    std::string actual_filename;
    int channels = 0;
    int rate = 0;
    bool must_record = false;
 
    bool reopen()
    {
      if(must_record)
      {
        // Open the file with the correct substitutions
        auto fname = QByteArray::fromStdString(this->filename);
        fname.replace("%t", QDateTime::currentDateTimeUtc().toString().toUtf8());
        actual_filename = fname.toStdString();
        f.open(actual_filename, channels, rate, 16);
        return false;
      }
      else
      {
        bool must_reply = false;
        if(f.is_open() && f.written_frames() > 0)
        {
          must_reply = true;
        }
        f.close();
        return must_reply;
      }
    }
 
    void write(int frames, audio_buffer& data)
    {
      int these_channels = data.size() / frames;
      if(these_channels != channels)
      {
        channels = these_channels;
        reopen();
      }
 
      if(!f.is_open())
        return;
 
      // Put addresses to the first sample of each channel in an array,
      // e.g. arr[0] points to the first channel, arr[1] to the second, etc.
      const double** arr = (const double**)alloca(channels * sizeof(double*));
      for(int c = 0; c < channels; ++c)
        arr[c] = data.data() + c * frames;
 
      // Write the data
      f.write_pcm_frames(frames, arr);
    }
  };
  std::shared_ptr<recorder_thread> impl = std::make_shared<recorder_thread>();
 
  struct reset_message
  {
    std::string path;
    int rate{};
    bool must_record{};
    bool operator()(recorder_thread& self)
    {
      using namespace std;
      swap(self.filename, path);
      self.rate = rate;
      self.must_record = must_record;
      return self.reopen();
    }
  };
 
  struct process_message
  {
    int frames{};
    audio_buffer data;
    bool operator()(recorder_thread& self)
    {
      self.write(frames, data);
      return false;
    }
  };
  using worker_message = ossia::variant<reset_message, process_message>;
 
  struct
  {
    std::function<void(std::shared_ptr<recorder_thread>, worker_message)> request;
    static std::function<void(AudioRecorder&)>
    work(std::shared_ptr<recorder_thread> t, worker_message&& mess)
    {
      bool reply = ossia::visit(
          [&]<typename M>(M&& msg) { return std::forward<M>(msg)(*t); },
          std::move(mess));
      if(reply)
      {
        return [filename = t->actual_filename](AudioRecorder& self) mutable {
          using namespace std;
          swap(self.filename_to_output, filename);
        };
      }
      else
      {
        return {};
      }
    }
  } worker;
 
  // Object definition
  struct
  {
    halp::dynamic_audio_bus<"Audio", double> audio;
    struct : halp::lineedit<"File pattern", "">
    {
      void update(AudioRecorder& self) { self.update(); }
    } filename;
 
    struct : halp::toggle<"Record">
    {
      void update(AudioRecorder& self)
      {
        if(prev != value)
        {
          prev = value;
          self.update();
        }
      }
      bool prev{false};
    } record;
  } inputs;
 
  struct
  {
    halp::callback<"Filename", std::string> finished;
  } outputs;
 
  int current_rate = 0;
  void prepare(halp::setup s) { current_rate = s.rate; }
 
  void update()
  {
    worker.request(impl, reset_message{inputs.filename, current_rate, inputs.record});
  }
 
  void operator()(int frames)
  {
    if(!std::exchange(started, true))
      update();
 
    data.resize(inputs.audio.channels * frames, boost::container::default_init);
    for(int c = 0; c < inputs.audio.channels; c++)
    {
      double* src = inputs.audio.samples[c];
      double* ptr = data.data() + c * frames;
      for(int i = 0; i < frames; i++)
        ptr[i] = src[i];
    }
 
    worker.request(impl, process_message{frames, std::move(data)});
 
    if(!filename_to_output.empty())
    {
      outputs.finished(filename_to_output);
      filename_to_output.clear();
    }
  }
 
  bool started{};
  std::optional<int64_t> first_message_sent_pos;
  std::optional<int64_t> last_message_sent_pos;
 
  audio_buffer data;
  std::string filename_to_output;
};
 
}