"""Unit tests for ``replace_single_quotes``.

This is the cleanest function to test: pure, recursive, no I/O. It escapes
single quotes (``'`` -> ``''``) for the Neo4j import, recursing through
dicts and lists and leaving non-strings untouched.
"""

import pytest
from hypothesis import given, strategies as st

import import_fhir_to_nx_diGraph as pipeline


def test_single_quote_in_string_is_doubled():
    assert pipeline.replace_single_quotes("O'Brien") == "O''Brien"


def test_string_without_quotes_unchanged():
    assert pipeline.replace_single_quotes("Mueller") == "Mueller"


def test_empty_string_unchanged():
    assert pipeline.replace_single_quotes("") == ""


@pytest.mark.parametrize("value", [0, 1, 3.14, None, True, False])
def test_non_string_scalars_unchanged(value):
    assert pipeline.replace_single_quotes(value) is value


def test_nested_dict_recurses():
    data = {"name": "O'Hara", "nested": {"note": "it's fine"}}
    assert pipeline.replace_single_quotes(data) == {
        "name": "O''Hara",
        "nested": {"note": "it''s fine"},
    }


def test_list_recurses():
    assert pipeline.replace_single_quotes(["a'b", 2, "c"]) == ["a''b", 2, "c"]


def test_dict_keys_are_not_escaped():
    # Only values are recursed into; keys are left as-is.
    result = pipeline.replace_single_quotes({"it's": "fine"})
    assert list(result.keys()) == ["it's"]
    assert result["it's"] == "fine"


# --- Property-based checks -------------------------------------------------

@given(st.text())
def test_every_quote_is_doubled(text):
    # The function is intentionally NOT idempotent: each pass doubles the
    # quote count. This pins that contract so a future "fix" is a conscious
    # choice rather than a silent behaviour change.
    result = pipeline.replace_single_quotes(text)
    assert result.count("'") == 2 * text.count("'")


@given(st.lists(st.one_of(st.integers(), st.text())))
def test_list_length_preserved(items):
    assert len(pipeline.replace_single_quotes(items)) == len(items)