#include "EQ.h"

namespace serum
{

void EQUnit::prepare (double sampleRate, int)
{
    sr = sampleRate;
    lowL.setSampleRate (sr);  lowR.setSampleRate (sr);
    midL.setSampleRate (sr);  midR.setSampleRate (sr);
    highL.setSampleRate (sr); highR.setSampleRate (sr);
    reset();
}

void EQUnit::reset()
{
    lowL.clear(); lowR.clear(); midL.clear(); midR.clear(); highL.clear(); highR.clear();
}

void EQUnit::process (float* l, float* r, int numSamples, const float p[4])
{
    const double lowGain  = (p[0] - 0.5f) * 2.0f * 15.0;
    const double midGain  = (p[1] - 0.5f) * 2.0f * 12.0;
    const double highGain = (p[2] - 0.5f) * 2.0f * 15.0;
    const double midFreq  = 200.0 + p[3] * 4800.0;

    lowL.setLowShelf (200.0, lowGain);    lowR.setLowShelf (200.0, lowGain);
    midL.setPeak (midFreq, midGain, 0.8); midR.setPeak (midFreq, midGain, 0.8);
    highL.setHighShelf (4000.0, highGain); highR.setHighShelf (4000.0, highGain);

    for (int i = 0; i < numSamples; ++i)
    {
        const float xL = l[i], xR = r[i];
        l[i] = highL.process (midL.process (lowL.process (xL)));
        r[i] = highR.process (midR.process (lowR.process (xR)));
    }
}

} // namespace serum