"""S-expression emitter tests."""

from tools.epro2.kicad._sexpr_reader import parse
from tools.epro2.kicad.sexpr import Sym, to_sexpr


def test_round_trip_simple():
    src = [Sym("kicad_sch"), [Sym("version"), 20231120], [Sym("paper"), "A4"]]
    text = to_sexpr(src, pretty=False)
    parsed = parse(text)
    assert parsed[0] == "kicad_sch"
    assert parsed[1] == ["version", 20231120]
    assert parsed[2] == ["paper", "A4"]


def test_string_escaping():
    text = to_sexpr([Sym("title"), 'a "quote" + \\backslash'], pretty=False)
    parsed = parse(text)
    assert parsed[1] == 'a "quote" + \\backslash'


def test_string_escapes_newlines_and_tabs():
    """KiCad 8 rejects literal newlines/CR/tabs inside quoted strings, so the
    emitter must escape them. Round-trip restores the original characters."""
    src = "Battary\n3.7V 700mAH\twith\rtab"
    text = to_sexpr([Sym("text"), src], pretty=False)
    # Raw text must NOT contain literal newline / CR / tab inside quotes
    assert "\\n" in text
    assert "\\r" in text
    assert "\\t" in text
    quoted = text[text.index('"'):text.rindex('"') + 1]
    assert "\n" not in quoted
    assert "\r" not in quoted
    assert "\t" not in quoted
    # Round-trip restores the original (our reader handles these escapes)
    parsed = parse(text)
    assert parsed[1] == src


def test_float_formatting_strips_trailing_zeros():
    text = to_sexpr([Sym("x"), 1.500000], pretty=False)
    assert "1.5" in text
    assert "1.500000" not in text


def test_bool_renders_as_yes_no():
    text = to_sexpr([Sym("hide"), True, False], pretty=False)
    parsed = parse(text)
    assert parsed == ["hide", "yes", "no"]


def test_pretty_indent_keeps_round_trip():
    src = [Sym("kicad_sch"),
           [Sym("wire"), [Sym("pts"), [Sym("xy"), 1.0, 2.0], [Sym("xy"), 3.0, 4.0]]]]
    pretty = to_sexpr(src, pretty=True)
    flat = to_sexpr(src, pretty=False)
    assert parse(pretty) == parse(flat)


def test_nan_inf_rejected():
    import math
    try:
        to_sexpr([Sym("x"), float("nan")])
    except ValueError:
        pass
    else:
        raise AssertionError("expected ValueError on NaN")
    try:
        to_sexpr([Sym("x"), math.inf])
    except ValueError:
        return
    raise AssertionError("expected ValueError on Inf")