"""Test plumbing: import path + notebook content served from tagged cells.

Content and client data live in the notebook, never in ``.py`` — the cells
tagged ``topic-bank`` and ``engagement-data`` in
``notebooks/cx_discovery.ipynb``. The fixtures below read those cells with
nbformat and exec them, so pytest pins the exact content the deliverable
ships (no kernel needed — tagged cells are self-contained by contract).

The sys.path insert makes discoverylib importable even without the study
venv active (the normal setup is ``pip install -e ".[dev]"`` into the
study-local ``.venv/``).
"""

from __future__ import annotations

import pathlib
import sys
from typing import Any

import pytest

STUDY_ROOT = pathlib.Path(__file__).resolve().parent.parent
sys.path.insert(0, str(STUDY_ROOT))

NOTEBOOK = STUDY_ROOT / "notebooks" / "cx_discovery.ipynb"


def tagged_cell_ns(tag: str) -> dict[str, Any]:
    """Exec the single cell carrying ``tag`` and return its namespace."""
    import nbformat

    nb = nbformat.read(NOTEBOOK, as_version=4)
    cells = [c for c in nb.cells if tag in c.metadata.get("tags", [])]
    assert len(cells) == 1, (
        f"expected exactly one cell tagged {tag!r} in {NOTEBOOK.name}, "
        f"found {len(cells)}"
    )
    ns: dict[str, Any] = {}
    exec(compile(cells[0].source, f"{NOTEBOOK.name} [{tag}]", "exec"), ns)
    return ns


@pytest.fixture(scope="session")
def topic_bank() -> dict[str, Any]:
    """The executed namespace of the notebook's topic-bank cell."""
    return tagged_cell_ns("topic-bank")


@pytest.fixture(scope="session")
def topics(topic_bank: dict[str, Any]) -> tuple[Any, ...]:
    """The TOPICS tuple as the deliverable defines it."""
    return topic_bank["TOPICS"]  # type: ignore[no-any-return]


@pytest.fixture(scope="session")
def topic_by_key(topics: tuple[Any, ...]) -> dict[str, Any]:
    return {t.key: t for t in topics}


@pytest.fixture(scope="session")
def engagement() -> dict[str, Any]:
    """The ENGAGEMENT dict as the deliverable's engagement-data cell ships it."""
    return tagged_cell_ns("engagement-data")["ENGAGEMENT"]  # type: ignore[no-any-return]