"""A lesson's name is one claim on one line (#4797).

`what` is the title every listing and menu prints. Written as the incident
instead of the claim, it turned a menu line into 1,416 characters with the
claim somewhere in the middle. Two halves are pinned: the doors refuse a new
one, and the menu shows one line for a name stored before they did.
"""
from __future__ import annotations

import inspect
from types import SimpleNamespace
from unittest.mock import AsyncMock, patch

import pytest

from scribe.mcp._context import _user_id_ctx
from scribe.mcp.tools.lessons import create_lesson, update_lesson
from scribe.services import lessons as lessons_svc
from scribe.services.lessons import WHAT_MAX_CHARS, claim_line, require_claim

TRIGGER = "an existing call is about to double as a liveness signal"
CLAIM = ("A check-in piggybacked on an existing call inherits every backoff "
         "that call is ever given")
STORY = (
    "The operator reported their agent showing offline while it ran. "
    + "The lease poll backed off to 900s while the roster called 300s stopped. " * 6
).strip()


# ── The bound ──────────────────────────────────────────────────────────────

def test_a_one_line_claim_passes():
    require_claim(CLAIM)
    require_claim("x" * WHAT_MAX_CHARS)


@pytest.mark.parametrize("what", [
    "x" * (WHAT_MAX_CHARS + 1),
    "A claim.\n\nAnd then the story of how it was learned.",
], ids=["over the bound", "several lines"])
def test_a_story_in_the_name_is_refused_with_where_it_goes(what):
    with pytest.raises(ValueError) as err:
        require_claim(what)
    message = str(err.value)
    assert "Nothing was written" in message
    assert "insight" in message, "the refusal must say where the story belongs"


# ── The doors ──────────────────────────────────────────────────────────────

@pytest.mark.asyncio
async def test_the_mcp_create_refuses_before_writing():
    _user_id_ctx.set(7)
    created = AsyncMock()
    with patch.object(lessons_svc, "create_lesson", created):
        with pytest.raises(ValueError):
            await create_lesson(what=STORY, when_to_apply=TRIGGER)
    created.assert_not_called()


@pytest.mark.asyncio
async def test_the_mcp_update_refuses_a_new_long_name():
    _user_id_ctx.set(7)
    updated = AsyncMock()
    with patch.object(lessons_svc, "update_lesson", updated):
        with pytest.raises(ValueError):
            await update_lesson(lesson_id=1, what=STORY)
    updated.assert_not_called()


@pytest.mark.asyncio
async def test_a_lesson_stored_with_a_long_name_can_still_be_edited():
    """Only a NEW name is checked. Refusing every edit of a lesson stored
    before the bound would also refuse the edit that repairs it."""
    _user_id_ctx.set(7)
    note = SimpleNamespace(
        id=1, title=STORY, body="b", tags=[], project_id=None,
        note_type="lesson", data={"what": STORY}, arose_from_id=None,
        created_at=None, updated_at=None,
    )
    updated = AsyncMock(return_value=note)
    with patch.object(lessons_svc, "update_lesson", updated), \
         patch("scribe.mcp.tools.lessons.systems_tools.attach_systems", AsyncMock()), \
         patch("scribe.mcp.tools.lessons.lesson_rules_svc.attach_lesson_rules", AsyncMock()):
        await update_lesson(lesson_id=1, when_to_apply=TRIGGER)
    assert updated.await_args.kwargs["what"] is None


@pytest.mark.parametrize("handler", ["create_lesson_route", "update_lesson_route"])
def test_the_rest_door_refuses_too(handler):
    """The web form writes lessons as well, and a bound one door enforces is
    a bound the other door walks around."""
    from scribe.routes import lessons as routes

    src = inspect.getsource(getattr(routes, handler))
    write = "lessons_svc." + handler.removesuffix("_route") + "("
    assert "require_claim(" in src
    assert src.index("require_claim(") < src.index(write), \
        "the check runs after the write it exists to prevent"


# ── The display ────────────────────────────────────────────────────────────

def test_a_short_name_is_shown_as_it_is():
    assert claim_line(CLAIM) == CLAIM


def test_a_stored_story_shows_as_its_first_sentence_marked_cut():
    line = claim_line(STORY)
    assert line == "The operator reported their agent showing offline while it ran. …"
    assert "\n" not in line


def test_a_first_sentence_past_the_bound_is_cut_at_a_word():
    line = claim_line("word " * 100)
    assert line.endswith(" …")
    assert len(line) <= WHAT_MAX_CHARS + 2


def test_the_menu_names_a_long_lesson_in_one_line():
    from scribe.services.plugin_context import _menu_name

    name = _menu_name(STORY, "lesson", {"what": STORY, "when_to_apply": TRIGGER}, "")
    assert name.endswith(" …")
    assert len(name) <= WHAT_MAX_CHARS + 2