"""Unit tests for the board data model (layers, units, transform, nets, clearance)."""

from __future__ import annotations

from freeroute.board import (
    ClearanceMatrix,
    CoordinateTransform,
    Layer,
    LayerStructure,
    Nets,
    Unit,
)


def test_unit_scale_and_parse():
    assert Unit.from_string("um") is Unit.UM
    assert Unit.from_string("MM") is Unit.MM
    assert Unit.from_string("bogus") is None
    assert Unit.scale(1.0, Unit.MM, Unit.UM) == 1000.0
    assert Unit.scale(1.0, Unit.INCH, Unit.MIL) == 1000.0
    assert str(Unit.MIL) == "mil"


def test_layer_structure_lookup():
    ls = LayerStructure([Layer("F.Cu", True), Layer("In1", False), Layer("B.Cu", True)])
    assert len(ls) == 3
    assert ls.get_no("F.Cu") == 0
    assert ls.get_no("B.Cu") == 2
    assert ls.get_no("missing") == -1
    assert ls.signal_layer_count() == 2
    assert ls.get_signal_layer(1).name == "B.Cu"


def test_coordinate_transform_roundtrip():
    t = CoordinateTransform(10)
    assert t.dsn_to_board(5) == 50
    assert t.board_to_dsn(50) == 5
    p = t.dsn_to_board_point(100, -200)
    assert (p.x, p.y) == (1000, -2000)
    back = t.board_to_dsn_point(p)
    assert (back.x, back.y) == (100.0, -200.0)


def test_nets_add_and_lookup():
    nets = Nets()
    a = nets.add("GND")
    b = nets.add("VCC", subnet_number=1)
    assert a.net_number == 1
    assert b.net_number == 2
    assert nets.max_net_no() == 2
    assert nets.get("GND") is a
    assert nets.get_by_number(2) is b
    assert nets.get("missing") is None
    assert nets.names() == {"GND", "VCC"}
    assert len(nets) == 2


def test_clearance_matrix_default_and_classes():
    cm = ClearanceMatrix.default_instance(200)
    assert cm.get_class_count() == 2  # null + default
    assert cm.get_name(0) == "null"
    assert cm.get_name(1) == "default"
    assert cm.get_value(1, 1) == 200
    assert cm.get_value(0, 1) == 0  # null class has no clearance
    via = cm.append_class("via")
    assert cm.get_no("via") == via
    cm.set_value(1, via, 300)
    assert cm.get_value(via, 1) == 300  # symmetric
    assert cm.get_value(1, 1, add_safety_margin=True) == 216  # +16 margin