"""Stage B1 PR 2 — executor persists across ``close()`` → ``open()``.

Replacement regression test for the deleted
``test_runtime_lifecycle.test_close_nulls_rpc_executor``. Before Stage B1 PR 2
of the post-refactoring plan, lifecycle close logic nulled out the client-owned
executor so a follow-up :meth:`open` would rebuild it against the new
``httpx.AsyncClient``.

PR 2 deleted both that null line and the lazy factory itself — the
executor is bound exactly once by the composition root
(:func:`notebooklm._runtime.init.compose_client_internals`) via
:class:`notebooklm._client_composed.ClientComposed`, and the same instance
survives any ``close()`` → ``open()`` cycle. This is safe because the executor's
transport collaborator (:class:`Kernel`) rebuilds its
``httpx.AsyncClient`` lazily on each :meth:`Kernel.open`, so a stale
executor reference continues to drive RPCs against a fresh transport.

This module pins three load-bearing invariants:

1. The :class:`RpcExecutor` instance is identity-equal before and after
   a full ``close()`` → ``open()`` cycle.
2. The reused executor can still execute an RPC after the cycle (it is
   not bound to a stale transport reference).
3. ``NotebookLMClient._rpc_executor`` is the same client-owned executor stored
   on ``ClientComposed``.
"""

from __future__ import annotations

from typing import Any

import pytest

from notebooklm.auth import AuthTokens
from notebooklm.rpc import RPCMethod
from tests._helpers.client_factory import build_client_shell_for_tests


def _make_auth() -> AuthTokens:
    return AuthTokens(
        cookies={"SID": "x", "__Secure-1PSIDTS": "y"},
        csrf_token="csrf",
        session_id="sid",
    )


@pytest.mark.asyncio
async def test_executor_identity_survives_close_then_open() -> None:
    """``open()`` → ``close()`` → ``open()`` preserves the executor instance.

    Pins the Stage B1 PR 2 contract: the composition root binds the
    executor exactly once and :meth:`ClientLifecycle.close` no longer
    nulls ``host._rpc_executor``. The same :class:`RpcExecutor`
    reference drives RPCs across the lifecycle cycle — feature
    adapters that captured the executor at construction time
    (``ChatAPI`` / ``SourcesAPI`` / etc.) do not need to re-grab it.
    """
    core = build_client_shell_for_tests(_make_auth())
    initial_executor = core._rpc_executor
    assert initial_executor is not None, "composition root must bind the executor"

    await core.__aenter__()
    try:
        assert core._rpc_executor is initial_executor, (
            "open() must not rebind the executor — it persists from composition"
        )
    finally:
        await core.close()

    # Stage B1 PR 2 dropped the close-time null on _rpc_executor; the
    # binding survives close().
    assert core._rpc_executor is initial_executor, (
        "close() must not null the executor — Stage B1 PR 2 dropped that step"
    )

    await core.__aenter__()
    try:
        assert core._rpc_executor is initial_executor, (
            "second open() also leaves the executor alone — same instance "
            "throughout the close()→open() cycle"
        )
    finally:
        await core.close()


@pytest.mark.asyncio
async def test_rpc_call_succeeds_after_close_then_open_with_same_executor() -> None:
    """A reused executor still executes RPCs after a full lifecycle cycle.

    Production callers reach the executor as ``client._rpc_executor``;
    if Stage B1 PR 2 had accidentally re-nulled the slot inside
    :meth:`ClientLifecycle.close`, the second dispatch after the cycle
    would raise ``AttributeError``. This test exercises the call path end-to-end
    through a stubbed executor to confirm the binding survives.
    """
    core = build_client_shell_for_tests(_make_auth())
    executor = core._rpc_executor
    assert executor is not None

    # Stub ``rpc_call`` on the executor with a plain async function
    # rather than ``unittest.mock.AsyncMock`` — ADR-0007 forbids
    # ``Mock`` / ``AsyncMock`` attribute assignment as a test seam, so
    # we use a captured-state ``async def`` to record the dispatch.
    # This is the same pattern as ``_fixtures/fake_core.py``: an
    # ordinary callable substituted for a method, no mock library
    # involved.
    sentinel: dict[str, Any] = {"call_count": 0}

    async def fake_rpc_call(*_args: Any, **_kwargs: Any) -> str:
        sentinel["call_count"] += 1
        return "ok"

    executor.rpc_call = fake_rpc_call  # type: ignore[method-assign,assignment]

    # Drive a full lifecycle cycle.
    await core.__aenter__()
    result1 = await core._rpc_executor.rpc_call(RPCMethod.LIST_NOTEBOOKS, [])
    await core.close()

    # Critical re-open + rpc_call — the deleted close-time null would
    # have left ``_rpc_executor`` at ``None`` here, raising from the
    # fail-fast guard.
    await core.__aenter__()
    try:
        result2 = await core._rpc_executor.rpc_call(RPCMethod.LIST_NOTEBOOKS, [])
    finally:
        await core.close()

    assert result1 == "ok"
    assert result2 == "ok"
    assert sentinel["call_count"] == 2
    # The executor reference never moved — both calls dispatched
    # through the same fake.
    assert core._rpc_executor is executor


def test_session_rpc_executor_forwards_to_client_composed() -> None:
    """``NotebookLMClient._rpc_executor`` reads through ``ClientComposed``."""
    core = build_client_shell_for_tests(_make_auth())

    assert core._rpc_executor is core._composed.executor