"""rebar_layout 테스트 (Rhino 없이 실행됩니다).

기준: docs/design_rules.md, 기존 프로젝트 rebar_pipeline/README.md §3
"""
import pytest

import rebar_layout as rl


# ---- 중심에서 바깥으로 배치 ----

def test_center_out_even_count_has_no_bar_on_center():
    assert rl.center_out_positions(4, 250) == [-375, -125, 125, 375]


def test_center_out_odd_count_has_bar_on_center():
    assert rl.center_out_positions(3, 250) == [-250, 0, 250]


def test_center_out_13_bars_goes_to_1500():
    # 2CYCLE: 0, ±250 ... ±1500
    pos = rl.center_out_positions(13, 250)
    assert len(pos) == 13
    assert pos[0] == -1500
    assert pos[-1] == 1500
    assert 0 in pos


def test_center_out_zero_bars_is_empty():
    assert rl.center_out_positions(0, 250) == []


def test_center_out_rejects_bad_input():
    with pytest.raises(ValueError):
        rl.center_out_positions(-1, 250)
    with pytest.raises(ValueError):
        rl.center_out_positions(5, 0)


# ---- 바깥 철근을 피복에 맞추는 배치 (1CYCLE) ----

def test_snapped_array_matches_1cycle_drawing():
    # 두부보 폭 3500, 피복 120, 14본, 간격 250
    pos = rl.snapped_array(14, 250, 3500, 120)
    assert len(pos) == 14
    assert pos[0] == -1630
    assert pos[1] == -1375
    assert pos[6] == -125
    assert pos[7] == 125
    assert pos[-2] == 1375
    assert pos[-1] == 1630


def test_snapped_array_is_symmetric_and_sorted():
    pos = rl.snapped_array(14, 250, 3500, 120)
    assert pos == sorted(pos)
    assert pos == [-p for p in reversed(pos)]


def test_snapped_array_outer_bars_sit_at_cover():
    pos = rl.snapped_array(14, 250, 3500, 120)
    assert max(pos) == 3500 / 2 - 120


def test_snapped_array_rejects_too_few_bars():
    with pytest.raises(ValueError):
        rl.snapped_array(1, 250, 3500, 120)


def test_snapped_array_rejects_when_inner_bars_pass_outer_bars():
    # 폭이 너무 좁아서 안쪽 철근이 바깥 철근을 넘어감
    with pytest.raises(ValueError):
        rl.snapped_array(14, 250, 2000, 120)


# ---- 수평 순간격 (KDS 24 14 21 4.5.3) ----

def test_min_horizontal_clear_h25_is_40mm():
    # max(1.5*25.4=38.1, 1.5*25=37.5, 40) = 40
    assert rl.min_horizontal_clear("H25", gmax=25) == pytest.approx(40.0)


def test_min_horizontal_clear_h29_uses_1_5db():
    assert rl.min_horizontal_clear("H29", gmax=25) == pytest.approx(1.5 * 28.6)


def test_min_horizontal_clear_large_aggregate_governs():
    assert rl.min_horizontal_clear("H25", gmax=40) == pytest.approx(60.0)


def test_clear_spacing_is_center_gap_minus_diameter():
    assert rl.clear_spacing(250, "H25") == pytest.approx(250 - 25.4)


def test_horizontal_spacing_ok_for_250_array():
    pos = rl.snapped_array(14, 250, 3500, 120)
    assert rl.horizontal_spacing_ok(pos, "H25", gmax=25)


def test_horizontal_spacing_fails_when_too_close():
    # 중심 간격 50 -> 순간격 24.6mm < 40mm
    assert not rl.horizontal_spacing_ok([0, 50], "H25", gmax=25)


# ---- 다단 연직 배치 ----

def test_min_vertical_clear_h25_is_db():
    # max(25, 25.4) = 25.4
    assert rl.min_vertical_clear("H25") == pytest.approx(25.4)


def test_min_vertical_clear_small_bar_uses_25mm():
    assert rl.min_vertical_clear("H16") == pytest.approx(25.0)


def test_vertical_pitch_100_ok_for_h25():
    assert rl.vertical_pitch_ok("H25", 100)


def test_vertical_pitch_40_fails_for_h25():
    # 순간격 14.6mm < 25.4mm
    assert not rl.vertical_pitch_ok("H25", 40)


def test_tier_elevations_go_down_from_top_cover():
    assert rl.tier_elevations(1000, 120, 2, 100) == [880, 780]


def test_tier_elevations_single_tier():
    assert rl.tier_elevations(1000, 120, 1, 100) == [880]


# ---- 수량, 중량 ----

def test_unit_weight_h25():
    assert rl.unit_weight("H25") == pytest.approx(3.98)


def test_unit_weight_unknown_bar_raises():
    with pytest.raises(ValueError):
        rl.unit_weight("H99")


def test_bar_weight_one_bar():
    # H25, 9.930m 1본 = 3.98 * 9.93
    assert rl.bar_weight("H25", 9930) == pytest.approx(3.98 * 9.93)


def test_array_summary_2cycle_main_bars():
    pos = rl.center_out_positions(13, 250)
    s = rl.array_summary("H25", 9930, pos)
    assert s["count"] == 13
    assert s["total_length_m"] == pytest.approx(13 * 9.93)
    assert s["weight_kg"] == pytest.approx(3.98 * 9.93 * 13)