from app.scoring import SCORE_FNS


def test_linear_decay_values():
    fn = SCORE_FNS["linear_decay"]
    assert fn(True, 0, 60_000) == 1.0
    assert fn(True, 30_000, 60_000) == 0.75
    assert fn(True, 60_000, 60_000) == 0.5
    # Past the deadline the score floors at 0.5 (still correct, fully decayed).
    assert fn(True, 90_000, 60_000) == 0.5
    assert fn(False, 0, 60_000) == 0.0


def test_linear_decay_snaps_to_grid():
    """Every score is on the 0.05 grid (21 distinct values)."""
    fn = SCORE_FNS["linear_decay"]
    for elapsed in range(0, 60_001, 137):  # arbitrary irrational-ish step
        s = fn(True, elapsed, 60_000)
        # multiplied by 20, must be an integer
        assert abs(s * 20 - round(s * 20)) < 1e-9, (elapsed, s)


def test_flat_values():
    fn = SCORE_FNS["flat"]
    assert fn(True, 0, 60_000) == 1.0
    assert fn(True, 60_000, 60_000) == 1.0
    assert fn(True, 90_000, 60_000) == 1.0
    assert fn(False, 0, 60_000) == 0.0


def test_exponential_decay_values():
    fn = SCORE_FNS["exponential_decay"]
    assert fn(True, 0, 60_000) == 1.0
    # At deadline: 0.5 + 0.5 * e^-2 ≈ 0.5677 → snaps to 0.55
    assert fn(True, 60_000, 60_000) == 0.55
    assert fn(True, 90_000, 60_000) == fn(True, 60_000, 60_000)
    assert fn(False, 0, 60_000) == 0.0