//
// This confidential and proprietary software may be used only as
// authorised by a licensing agreement from ARM Limited
// (C) COPYRIGHT 2020-2024 ARM Limited
// ALL RIGHTS RESERVED
// The entire notice above must be reproduced on all authorised
// copies and copies may only be made to the extent permitted
// by a licensing agreement from ARM Limited.

ERROR_IF(!power_of_two(H));
ERROR_IF(!power_of_two(W));

float sign_val = 1.0;

if (inverse) {
    sign_val = -1.0;
}

for_each(0 <= n < N, 0 <= oy < H, 0 <= ox < W) {
    in_out_t sum_real = 0.0;
    in_out_t sum_imag = 0.0;
    for_each(0 <= iy < H, 0 <= ix < W) {
        in_out_t val_real = tensor_read<in_out_t>(input_real, [N,H,W], [n,iy,ix]);
        in_out_t val_imag = tensor_read<in_out_t>(input_imag, [N,H,W], [n,iy,ix]);
        int32_t ay = (static_cast<size_t>(iy) * static_cast<size_t>(oy)) % static_cast<int32_t>(H);
        int32_t ax = (static_cast<size_t>(ix) * static_cast<size_t>(ox)) % static_cast<int32_t>(W);
        in_out_t a = sign_val * 2 * pi() * (static_cast<in_out_t>(ay) / H + static_cast<in_out_t>(ax) / W);
        sum_real +=  val_real * cos(a) + val_imag * sin(a);
        sum_imag += -val_real * sin(a) + val_imag * cos(a);
    }
    tensor_write<in_out_t>(output_real, [N,H,W], [n,oy,ox], sum_real);
    tensor_write<in_out_t>(output_imag, [N,H,W], [n,oy,ox], sum_imag);
}