#pragma once
#include <Figments.h>
#include <ArduinoJson.h>
#include "../Config.h"

class BPM : public InputSource, ConfigTaskMixin {
public:
  BPM() : InputSource("BPM") {}
  void handleEvent(const InputEvent& evt) override {
      if (evt.intent == InputEvent::BeatDetect) {
        m_nextBpm = millis();
        m_timings.insert(millis());
        Log.trace("bpm: %d timings", m_timings.size());
        if (m_timings.size() >= 5) {
          updateBPM();
        }
      }
      ConfigTaskMixin::handleEvent(evt);
  }

  void loop() {
      InputSource::loop();
      ConfigTaskMixin::loop();
  }

  void handleConfigChange(const Configuration& cfg) override {
    double requestedBPM = cfg.get("bpm.idle", msToBPM(m_msPerBeat));
    m_msPerBeat = 60000.0 / (double)requestedBPM;
    Log.notice("bpm: idle BPM set to %d (requested %d)", (int)msToBPM(m_msPerBeat), (int)requestedBPM);
  }

  InputEvent read() override {
    if (m_msPerBeat > 0) {
      uint16_t now = millis();
      if (now >= m_nextBpm) {
        m_nextBpm += m_msPerBeat;
        return InputEvent{InputEvent::Beat, msToBPM(m_msPerBeat)};
      }
      if (now >= m_nextLearn && m_nextLearn != 0) {
        m_timings.clear();
        m_nextLearn = 0;
      }
    }
    return InputEvent{};
  }

private:
  uint16_t m_msPerBeat = 60000;
  uint16_t m_nextBpm = 0;
  uint16_t m_nextLearn = 0;
  Ringbuf<uint16_t, 7> m_timings;

  constexpr uint16_t msToBPM(float msPerBeat) const {
      if (msPerBeat == 0) {
          return 0;
      }
      return 60000.0 / msPerBeat;
  }

  void updateBPM() {
    uint16_t avgDelta = 0;
    for(uint8_t i = 0; i < m_timings.size() - 1; i++) {
      uint16_t delta = m_timings.peek(i+1) - m_timings.peek(i);
      Log.trace("bpm: Timing %d Delta %d", m_timings.peek(i), delta);
      avgDelta += delta;
    }
    m_msPerBeat = avgDelta / 4;
    m_nextLearn = m_msPerBeat * 5 + millis();
    Log.notice("bpm: BPM is now %d", msToBPM(m_msPerBeat));
    uint16_t trash;
    m_timings.take(trash);
  }
};