//
// Created by versustune on 12.06.20.
//

#include "FFT.h"

void FFT::pushNextSampleIntoFifo(float sample) noexcept {
    {
        if (fifoIndex == fftSize)    // [11]
        {
            if (!nextFFTBlockReady) // [12]
            {
                zeromem(fftData, sizeof(fftData));
                memcpy(fftData, fifo, sizeof(fifo));
                nextFFTBlockReady = true;
            }
            fifoIndex = 0;
        }

        fifo[fifoIndex++] = sample;  // [12]
    }
}

void FFT::drawNextFrameOfSpectrum() {
    window.multiplyWithWindowingTable(fftData, fftSize);      // [1]
    fft.performFrequencyOnlyForwardTransform(fftData); // [2]

    auto mindB = -80.0f;
    auto maxdB = 0.0f;
    for (int i = 0; i < scopeSize; ++i)
    {
        auto level = jmap(Decibels::gainToDecibels(fftData[i], mindB), mindB, maxdB, -1.0f, 1.0f);
        scopeData[i] = level;
    }
}