from nebulaforge.qdiff import create_qdiff, apply_qdiff, manifest_proofs


def test_qdiff_create_and_apply_identity():
    base = [0.0, 1.0, 2.0, -1.0]
    new = [0.0, 1.0, 2.0, -1.0]
    bundle = create_qdiff(base, new)
    out = apply_qdiff(base, bundle)
    # exact equality for identical arrays
    assert out == new


def test_qdiff_quantized_residuals_and_topk():
    base = [0.0, 0.0, 0.0, 0.0]
    new = [0.0, 10.0, -5.0, 2.0]
    # keep only top-2 residuals
    bundle = create_qdiff(base, new, top_k=2, chunk_size=8)
    out = apply_qdiff(base, bundle)
    # Reconstructed values should be close to original for top-k kept; others may be zero
    # Check that at least two elements match closely
    matches = sum(1 for a, b in zip(out, new) if abs(a - b) < 1e-2)
    assert matches >= 2


def test_manifest_hashes():
    base = [0.0] * 16
    new = [i * 0.1 for i in range(16)]
    bundle = create_qdiff(base, new, chunk_size=7)
    proofs = manifest_proofs(bundle)
    # every manifest entry should have a corresponding proof equal to the key
    for k, v in proofs.items():
        assert k == v