"""Keep registered use-case coverage present before any marker deselection."""

import pytest

from tests.usecases.registry import load_cases, validate_coverage


@pytest.fixture(scope="session")
def django_db_modify_db_settings(
    tmp_path_factory, django_db_modify_db_settings_parallel_suffix,
):
    """Give browser request threads separate connections to an isolated database.

    Django's in-memory live-server path shares one SQLite connection between
    request threads. Parallel private-image reads race its debug-query cursor.
    A per-run/worker temporary file preserves transactions and permits the same
    concurrent browser traffic as the app's PostgreSQL deployment.
    """
    from django.conf import settings

    directory = tmp_path_factory.mktemp("csoc-test-db")
    settings.DATABASES["default"].setdefault("TEST", {})["NAME"] = str(
        directory / "test.sqlite3"
    )


def pytest_addoption(parser):
    parser.addoption("--verify-usecases", action="store_true",
                     help="Fail if established use cases lose registered test coverage")


@pytest.hookimpl(tryfirst=True)
def pytest_collection_modifyitems(config, items):
    if not config.getoption("--verify-usecases"):
        return
    collected = {}
    for item in items:
        collected[item.nodeid] = {
            "usecases": {m.args[0] for m in item.iter_markers("usecase") if m.args},
            "browser": item.get_closest_marker("browser") is not None,
            "disabled": any(item.get_closest_marker(m) for m in ("skip", "skipif", "xfail")),
        }
    try:
        validate_coverage(load_cases(), collected)
    except (KeyError, ValueError, TypeError, OSError) as exc:
        raise pytest.UsageError(f"Use-case regression contract failed: {exc}") from exc