/**
 ******************************************************************************
 * Xenia : Xbox 360 Emulator Research Project                                 *
 ******************************************************************************
 * Copyright 2021 Ben Vanik. All rights reserved.                             *
 * Released under the BSD license - see LICENSE in the root for more details. *
 ******************************************************************************
 */

#ifndef XENIA_APU_CONVERSION_H_
#define XENIA_APU_CONVERSION_H_

#include <cstdint>

#include "xenia/base/byte_order.h"

namespace xe {
namespace apu {
namespace conversion {

inline void sequential_6_BE_to_interleaved_6_LE(float* output,
                                                const float* input,
                                                size_t ch_sample_count) {
  for (size_t sample = 0; sample < ch_sample_count; sample++) {
    for (size_t channel = 0; channel < 6; channel++) {
      output[sample * 6 + channel] =
          xe::byte_swap(input[channel * ch_sample_count + sample]);
    }
  }
}
inline void sequential_6_BE_to_interleaved_2_LE(float* output,
                                                const float* input,
                                                size_t ch_sample_count) {
  // Default 5.1 channel mapping is fl, fr, fc, lf, bl, br
  // https://docs.microsoft.com/en-us/windows/win32/xaudio2/xaudio2-default-channel-mapping
  for (size_t sample = 0; sample < ch_sample_count; sample++) {
    // put center on left and right, discard low frequency
    float fl = xe::byte_swap(input[0 * ch_sample_count + sample]);
    float fr = xe::byte_swap(input[1 * ch_sample_count + sample]);
    float fc = xe::byte_swap(input[2 * ch_sample_count + sample]);
    float br = xe::byte_swap(input[4 * ch_sample_count + sample]);
    float bl = xe::byte_swap(input[5 * ch_sample_count + sample]);
    float center_halved = fc * 0.5f;
    output[sample * 2] = (fl + bl + center_halved) * (1.0f / 2.5f);
    output[sample * 2 + 1] = (fr + br + center_halved) * (1.0f / 2.5f);
  }
}

}  // namespace conversion
}  // namespace apu
}  // namespace xe

#endif