import pytest

from rag.calculators import body_surface_area_m2


def test_bsa_matches_book_worked_example():
    # Dược thư Phụ lục 1: "165 cm và 60 kg sẽ có diện tích 1,66 m²".
    assert round(body_surface_area_m2(60, 165), 2) == 1.66


def test_bsa_matches_book_table_cells():
    # Independent cells read from the BSA table (printed 1499): ground truth.
    assert round(body_surface_area_m2(10, 90), 2) == 0.50
    assert round(body_surface_area_m2(70, 170), 2) == 1.81


def test_bsa_rejects_nonpositive_inputs():
    with pytest.raises(ValueError):
        body_surface_area_m2(0, 165)
    with pytest.raises(ValueError):
        body_surface_area_m2(60, -1)