import torch
from safetensors.torch import load_file

def load_model(path='model.safetensors'):
    return load_file(path)

def tristate4(e, d3, d2, d1, d0, weights):
    """4-bit tristate buffer. E=1 passes data, E=0 outputs zeros."""
    inp = torch.tensor([float(e), float(d3), float(d2), float(d1), float(d0)])

    y0 = int((inp @ weights['y0.weight'].T + weights['y0.bias'] >= 0).item())
    y1 = int((inp @ weights['y1.weight'].T + weights['y1.bias'] >= 0).item())
    y2 = int((inp @ weights['y2.weight'].T + weights['y2.bias'] >= 0).item())
    y3 = int((inp @ weights['y3.weight'].T + weights['y3.bias'] >= 0).item())

    return y3, y2, y1, y0

if __name__ == '__main__':
    w = load_model()
    print('4-bit Tristate Buffer:')
    for e in [0, 1]:
        for d in [5, 10]:
            d3, d2, d1, d0 = (d >> 3) & 1, (d >> 2) & 1, (d >> 1) & 1, d & 1
            y3, y2, y1, y0 = tristate4(e, d3, d2, d1, d0, w)
            print(f'  E={e}, D={d3}{d2}{d1}{d0} -> {y3}{y2}{y1}{y0}')