metronome.h

// SPDX-FileCopyrightText: © 2019-2021, 2024-2026 Alexandros Theodotou <alex@zrythm.org>
// SPDX-License-Identifier: LicenseRef-ZrythmLicense
 
#pragma once
 
#include "dsp/audio_sample_processor.h"
#include "dsp/tempo_map.h"
 
#include <QtQmlIntegration/qqmlintegration.h>
 
#include <juce_audio_basics/juce_audio_basics.h>
 
namespace zrythm::dsp
{
class Metronome : public QObject, public AudioSampleProcessor
{
  Q_OBJECT
  Q_PROPERTY (float volume READ volume WRITE setVolume NOTIFY volumeChanged)
  Q_PROPERTY (bool enabled READ enabled WRITE setEnabled NOTIFY enabledChanged)
  QML_ELEMENT
  QML_UNCREATABLE ("")
 
public:
  Metronome (
    ProcessorBaseDependencies dependencies,
    juce::AudioSampleBuffer   emphasis_sample,
    juce::AudioSampleBuffer   normal_sample,
    bool                      initially_enabled = true,
    float                     initial_volume = 1.f,
    QObject *                 parent = nullptr);
 
  // ============================================================================
  // QML Interface
  // ============================================================================
 
  float volume () const { return volume_.load (); }
  void  setVolume (float volume)
  {
    if (utils::values_equal_for_qproperty_type (volume_.load (), volume))
      return;
 
    volume_.store (volume);
    Q_EMIT volumeChanged (volume);
  }
  Q_SIGNAL void volumeChanged (float volume);
 
  bool enabled () const { return enabled_.load (); }
  void setEnabled (bool enabled)
  {
    if (utils::values_equal_for_qproperty_type (enabled_.load (), enabled))
      return;
 
    enabled_.store (enabled);
    Q_EMIT enabledChanged (enabled);
  }
  Q_SIGNAL void enabledChanged (bool enabled);
 
  // ============================================================================
 
  void custom_process_block (
    dsp::graph::EngineProcessTimeInfo time_nfo,
    const dsp::ITransport            &transport,
    const dsp::TempoMap              &tempo_map) noexcept override;
 
  void custom_prepare_for_processing (
    const graph::GraphNode * node,
    units::sample_rate_t     sample_rate,
    units::sample_u32_t      max_block_length) override;
 
private:
  void find_and_queue_metronome_samples (
    const dsp::TempoMap &tempo_map,
    units::sample_t      start_pos,
    units::sample_t      end_pos,
    units::sample_t      loffset);

  void queue_metronome_countin (
    const dsp::graph::EngineProcessTimeInfo &time_nfo,
    const dsp::ITransport                   &transport,
    const dsp::TempoMap                     &tempo_map);

  void queue_metronome (
    bool                 emphasis,
    units::sample_t      offset,
    std::source_location loc = std::source_location::current ());
 
private:
  juce::AudioSampleBuffer emphasis_sample_buffer_;

  juce::AudioSampleBuffer normal_sample_buffer_;

  std::atomic<float> volume_;
 
  std::atomic_bool enabled_;
};
 
} // namespace zrythm::dsp