"""Packaging invariants — version/solver single-sourcing and dependency hygiene.

Pure static checks over the repository files. No imports of :mod:`otko`,
Qt or the solver stack, so this test runs anywhere (including Windows 3.12).
"""

from __future__ import annotations

import re
from pathlib import Path

try:  # Python 3.11+
    import tomllib
except ModuleNotFoundError:  # pragma: no cover - Python 3.10 backport
    import tomli as tomllib

REPO_ROOT = Path(__file__).resolve().parents[2]
SRC_ROOT = REPO_ROOT / "src" / "otko"
PYPROJECT = REPO_ROOT / "pyproject.toml"

_VERSION_RE = re.compile(r"^__version__\s*=", re.MULTILINE)


def _pyproject() -> dict:
    with PYPROJECT.open("rb") as handle:
        return tomllib.load(handle)


def _src_files() -> list[Path]:
    return sorted(SRC_ROOT.rglob("*.py"))


def _dep_name(requirement: str) -> str:
    """Return the lowercased distribution name from a PEP 508 requirement."""
    match = re.match(r"^\s*([A-Za-z0-9][A-Za-z0-9._-]*)", requirement)
    return match.group(1).lower().replace("_", "-") if match else ""


def test_console_script_entrypoint() -> None:
    assert _pyproject()["project"]["scripts"]["otko"] == "otko.__main__:main"


def test_project_version_is_dynamic() -> None:
    project = _pyproject()["project"]
    assert "version" not in project
    assert project["dynamic"] == ["version"]


def test_single_version_assignment() -> None:
    hits = [path for path in _src_files() if _VERSION_RE.search(path.read_text(encoding="utf-8"))]
    assert len(hits) == 1, f"expected exactly one __version__ assignment, got {hits}"
    assert hits[0] == SRC_ROOT / "_const.py"


def test_solver_version_literal_only_in_const() -> None:
    hits = [path for path in _src_files() if "3.8.0.0" in path.read_text(encoding="utf-8")]
    assert hits == [SRC_ROOT / "_const.py"], f"unexpected 3.8.0.0 occurrences: {hits}"


def test_ruff_line_length_and_ignore() -> None:
    ruff = _pyproject()["tool"]["ruff"]
    assert ruff["line-length"] == 100
    assert "E501" in ruff["lint"]["ignore"]


def test_no_phantom_scipy_pandas_dependencies() -> None:
    project = _pyproject()["project"]
    groups = [project.get("dependencies", [])]
    groups.extend(project.get("optional-dependencies", {}).values())
    declared = {_dep_name(req) for group in groups for req in group}
    assert "scipy" not in declared
    assert "pandas" not in declared