"""Tests for :class:`app.services.pages.PageService`.

Uses the session-scoped seeded ``db_engine`` fixture.
"""

from __future__ import annotations

from sqlalchemy import Engine

from app.models.entities import Page
from app.services.pages import PageService


def test_get_by_slug_returns_seeded_about_page(db_engine: Engine) -> None:
    """The seeded About page loads as a :class:`Page` dataclass."""
    service = PageService(db_engine)
    page = service.get_by_slug("about")

    assert page is not None
    assert isinstance(page, Page)
    assert page.slug == "about"
    assert page.title == "About the Farm"
    # The sanitized HTML must contain a <p> since the seed Markdown
    # has multiple paragraphs; this also proves the Markdown pipeline
    # ran at seed time.
    assert "<p>" in page.body_html_cached
    assert page.published is True


def test_get_by_slug_returns_none_for_unknown_slug(db_engine: Engine) -> None:
    """Unknown slugs return ``None`` rather than raising."""
    service = PageService(db_engine)
    assert service.get_by_slug("does-not-exist") is None


def test_get_by_slug_is_cached(db_engine: Engine) -> None:
    """The TTL cache wraps page lookups keyed by slug."""
    service = PageService(db_engine)
    first = service.get_by_slug("about")
    second = service.get_by_slug("about")
    assert first is second


def test_invalidate_all_forces_reload(db_engine: Engine) -> None:
    """After :meth:`invalidate_all` the next call re-hits the DB."""
    service = PageService(db_engine)
    first = service.get_by_slug("about")
    service.invalidate_all()
    second = service.get_by_slug("about")
    assert first is not second
    # Same slug, same row — content equal, identity different.
    assert first is not None and second is not None
    assert first.slug == second.slug == "about"