esp32i2s/include/NoteDetector.h

#pragma once

#include <Arduino.h>
#include <arduinoFFT.h>
#include <vector>
#include <deque>
#include "Config.h"

struct DetectedNote {
    float frequency;
    float magnitude;
    uint8_t noteNumber;  // MIDI note number for easy identification
    uint32_t startTime;  // When the note was first detected
    uint32_t lastSeenTime; // Last time this note was detected
};

class NoteDetector {
public:
    NoteDetector();
    void analyzeSamples(const int16_t* samples, size_t sampleCount);
    const std::vector<DetectedNote>& getDetectedNotes() const { return detectedNotes; }
    const double* getSpectrum() const { return vReal; }
    void beginCalibration();
    void endCalibration();
    bool isCalibrating() const { return calibrationMode; }
    
    // Threshold adjustment methods
    void adjustThreshold(float delta);
    float getCurrentThreshold() const { return dynamicThreshold; }

private:
    arduinoFFT FFT;
    double vReal[Config::FFT_SIZE];
    double vImag[Config::FFT_SIZE];
    std::vector<DetectedNote> detectedNotes;
    std::deque<float> peakMagnitudeHistory;  // For calibration
    
    bool calibrationMode;
    uint32_t calibrationStartTime;
    float dynamicThreshold;
    
    uint8_t freqToNoteNumber(float frequency) const;
    bool isNoteFrequency(float frequency) const;
    bool isHarmonic(float freq1, float freq2, float tolerance) const;
    void findPeaks();
    void updateNoteTimings();
    void calculateDynamicThreshold();
};