#include "SubOscillator.h"

namespace serum
{

void SubOscillator::noteOn (double freqHz, int octaveShift)
{
    // octaveShift: -2, -1 or 0 (from the subOct param).
    const double mult = (octaveShift == -2) ? 0.25 : (octaveShift == -1) ? 0.5 : 1.0;
    (void) freqHz;
    (void) mult;
    phase = 0.0;
}

void SubOscillator::processAdd (double freqHz, int shape, float level, float& out) noexcept
{
    if (level <= 0.0f || freqHz <= 0.0)
        return;

    // The octave shift is baked into freqHz by the voice; here we just phase-accumulate.
    const double inc = kTwoPi * freqHz / sr;
    phase += inc;
    phase -= std::floor (phase * (1.0 / kTwoPi)) * kTwoPi;

    float s = 0.0f;
    if (shape == (int) SubShape::Triangle)
    {
        const float p = (float) (phase * (1.0 / kTwoPi));
        s = 1.0f - 4.0f * std::abs (p - 0.5f);
    }
    else
    {
        s = (float) std::sin (phase);
    }

    out += s * level;
}

} // namespace serum