#include "Sine.hpp"

namespace muz
{
  /*explicit*/ Sine::Sine(AudioConf const& conf,
                          std::unique_ptr<Signal> freq,
                          std::unique_ptr<Signal> amplitude)
    : m_conf { conf }
    , m_freq { std::move(freq) }
    , m_amplitude { std::move(amplitude) }
  {
    for (size_t i=0; i<static_cast<size_t>(m_conf.channels()); i++)
      {
        m_phases.push_back(0.0f);
      }
  }

  /*virtual*/ Sine::~Sine()
  {
  }

  std::vector<float> Sine::next() /*override*/
  {
    assert(m_freq);
    assert(m_amplitude);

    std::vector<float> out;
    auto freqs = m_freq->next();
    auto amps = m_amplitude->next();

    if (freqs.size() != amps.size()
        || freqs.size() != m_phases.size())
      {
        throw signal_error {"cannot generate sine: channel number mismatch"};
      }

    for (size_t i=0; i<static_cast<size_t>(m_conf.channels()); i++)
      {
        float const value = amps[i] * std::sin(m_phases[i]);

        m_phases[i] += 2 * M_PI * freqs[i]
          / static_cast<float>(m_conf.samplerate());

        out.push_back(value);
      }

    return out;
  }
}