"""Unit: TTL cache daftar lesson — menyegarkan diri tanpa restart.

Produksi gunicorn multi-worker: `invalidate_lesson_caches()` hanya membersihkan
cache di worker yang menangani publish. Worker lain harus menyegarkan diri
sendiri setelah TTL, agar perubahan home.md/sub-home.md tidak "nyangkut"
sampai proses di-restart.
"""

import os
import time

import pytest

from services import lesson_service

pytestmark = pytest.mark.unit


def _write_home(tmp_path, slugs, bump=0.0):
    """Tulis home.md + file lesson untuk daftar slug. `bump` menggeser mtime
    agar perubahan file selalu terdeteksi (mtime presisi sub-detik)."""
    lines = ["# Home", "", "---Available_Lessons---"]
    for slug in slugs:
        (tmp_path / f"{slug}.md").write_text(f"# {slug}\nisi", encoding="utf-8")
        lines.append(f"- [{slug}]({slug}.md)")
    home = tmp_path / "home.md"
    home.write_text("\n".join(lines) + "\n", encoding="utf-8")
    if bump:
        stamp = time.time() + bump
        os.utime(home, (stamp, stamp))


def _filenames():
    return [lesson["filename"] for lesson in lesson_service.get_lessons()]


def test_list_cache_refreshes_after_ttl(tmp_path, monkeypatch):
    _write_home(tmp_path, ["alpha"])
    monkeypatch.setattr("services.lesson_service.CONTENT_DIR", str(tmp_path))
    lesson_service.invalidate_lesson_caches()

    assert _filenames() == ["alpha.md"]

    # home.md berubah, tetapi masih di dalam TTL → cache lama tetap dipakai.
    _write_home(tmp_path, ["alpha", "beta"], bump=1)
    assert _filenames() == ["alpha.md"]

    # TTL habis → worker mem-parse ulang tanpa invalidasi eksplisit.
    monkeypatch.setattr("services.lesson_service._LESSON_LIST_CACHE_TTL_SECONDS", 0.0)
    assert _filenames() == ["alpha.md", "beta.md"]


def test_explicit_cache_clear_still_works(tmp_path, monkeypatch):
    _write_home(tmp_path, ["alpha"])
    monkeypatch.setattr("services.lesson_service.CONTENT_DIR", str(tmp_path))
    lesson_service.invalidate_lesson_caches()

    assert _filenames() == ["alpha.md"]

    # In-process publish boleh membersihkan cache lebih awal dari TTL.
    _write_home(tmp_path, ["alpha", "beta"], bump=1)
    lesson_service.invalidate_lesson_caches()
    assert _filenames() == ["alpha.md", "beta.md"]


# ── Signature evaluasi (deteksi perubahan saat publish) ─────────────

_EXERCISE = "# L\n\n---INITIAL_CODE---\n```c\nint main(){}\n```\n"
_MCQ = "\n---QUIZ_MCQ---\n### Q?\n- [x] A\n- [] B\n---END_QUIZ_MCQ---\n"
_WEIGHTED = "\n---QUIZ_WEIGHTED---\n### Q?\n- [10] A\n- [ ] B\n---END_QUIZ_WEIGHTED---\n"


def test_evaluation_signature_detects_quiz_type_change():
    base = lesson_service.get_evaluation_signature(_EXERCISE)
    assert base == {
        "has_exercise": True,
        "has_quiz": False,
        "quiz_kinds": [],
        "quiz_total": 0,
    }

    with_mcq = lesson_service.get_evaluation_signature(_EXERCISE + _MCQ)
    assert with_mcq["has_quiz"] is True
    assert with_mcq["quiz_kinds"] == ["mcq"]
    assert with_mcq["quiz_total"] == 1

    with_weighted = lesson_service.get_evaluation_signature(_EXERCISE + _WEIGHTED)
    assert with_weighted["quiz_kinds"] == ["weighted"]
    assert with_weighted["quiz_total"] == 100

    # MCQ → weighted harus terdeteksi sebagai perubahan.
    assert with_mcq != with_weighted


def test_evaluation_signature_invalid_quiz_raises():
    with pytest.raises(ValueError):
        lesson_service.get_evaluation_signature(
            "# L\n\n---QUIZ_MCQ---\n### Q?\n- [x] A\n- [x] B\n---END_QUIZ_MCQ---\n"
        )