from app.services.math_structure_scanner import (
    MathStructureKind,
    scan_math_structures,
)


def test_scanner_preserves_composite_assign_set_as_single_match() -> None:
    text = "S = {3} et x = 3 et 3 noyés dans le texte, aussi {3} ici"

    matches = scan_math_structures(text)

    assert [item.kind for item in matches] == [
        MathStructureKind.ASSIGN_SET,
        MathStructureKind.ASSIGN_NUM,
        MathStructureKind.BARE_NUMBER,
        MathStructureKind.SET_LITERAL,
    ]

    assert matches[0].text == "S = {3}"
    assert matches[0].normalized_text == "S={3}"
    assert matches[0].children == {
        "target": "S",
        "value": "{3}",
        "elements": ["3"],
    }
    assert matches[0].ambiguous is False

    assert matches[1].text == "x = 3"
    assert matches[1].children == {
        "target": "x",
        "value": "3",
    }
    assert matches[1].ambiguous is False

    assert matches[2].text == "3"
    assert matches[2].ambiguous is True

    assert matches[3].text == "{3}"
    assert matches[3].children == {"elements": ["3"]}
    assert matches[3].ambiguous is False


def test_scanner_handles_negative_and_multi_value_sets() -> None:
    text = "Après calcul, on obtient S={-2, 4}."

    matches = scan_math_structures(text)

    assert len(matches) == 1
    assert matches[0].kind == MathStructureKind.ASSIGN_SET
    assert matches[0].text == "S={-2, 4}"
    assert matches[0].normalized_text == "S={-2,4}"
    assert matches[0].children == {
        "target": "S",
        "value": "{-2,4}",
        "elements": ["-2", "4"],
    }
    assert matches[0].ambiguous is False


def test_scanner_handles_embedded_variable_assignment() -> None:
    text = "La solution finale est x=-2."

    matches = scan_math_structures(text)

    assert len(matches) == 1
    assert matches[0].kind == MathStructureKind.ASSIGN_NUM
    assert matches[0].text == "x=-2"
    assert matches[0].children == {
        "target": "x",
        "value": "-2",
    }
    assert matches[0].ambiguous is False


def test_scanner_marks_bare_number_as_ambiguous() -> None:
    text = "Donc 3 est la solution."

    matches = scan_math_structures(text)

    assert len(matches) == 1
    assert matches[0].kind == MathStructureKind.BARE_NUMBER
    assert matches[0].text == "3"
    assert matches[0].children == {}
    assert matches[0].ambiguous is True