"""PLAN 472-6 6-A — [저장] · [확정] 한 본문 창구의 원자성.

합성 repository와 ``tmp_path`` storage만 사용해 중간 실패 rollback, 복구 실패 표시,
정상 commit, 같은 프로젝트 동시 저장 직렬화를 지킨다.
"""

from __future__ import annotations

import asyncio
import copy
import json
import sys
from dataclasses import dataclass
from pathlib import Path
from uuid import UUID

import pytest

HERE = Path(__file__).resolve().parent
ROOT = HERE.parents[1]
sys.path.insert(0, str(ROOT))

from B06_Section import B06_Section_Router_DesignSave as design  # noqa: E402
from B06_Section.B06_Section_Router_DesignSave_Route import StepFailed  # noqa: E402
from common_util import common_util_save_guard as guard  # noqa: E402

PROJECT = UUID("00000000-0000-0000-0000-000000000472")


def test_storage_되돌림은_바뀐_것만(tmp_path: Path) -> None:
    (tmp_path / "B06_Section" / "a").mkdir(parents=True)
    keep = tmp_path / "B06_Section" / "a" / "keep.json"
    edit = tmp_path / "B06_Section" / "edit.json"
    gone = tmp_path / "workflow.json"
    for path, text in ((keep, "k"), (edit, "e"), (gone, "w")):
        path.write_text(text, encoding="utf-8")
    outside = tmp_path / "B03_FileInput.txt"
    outside.write_text("o", encoding="utf-8")
    snap = guard.snapshot_storage(tmp_path, ("B06_Section", "workflow.json"))
    kept_stamp = keep.stat().st_mtime_ns
    edit.write_text("changed", encoding="utf-8")
    gone.unlink()
    (tmp_path / "B06_Section" / "new.json").write_text("n", encoding="utf-8")
    outside.write_text("o2", encoding="utf-8")
    assert snap.changed() == ["B06_Section/edit.json", "B06_Section/new.json", "workflow.json"]
    assert snap.restore() == 3
    assert edit.read_text(encoding="utf-8") == "e" and gone.read_text(encoding="utf-8") == "w"
    assert not (tmp_path / "B06_Section" / "new.json").exists()
    assert keep.stat().st_mtime_ns == kept_stamp and outside.read_text(encoding="utf-8") == "o2"
    snap.discard()
    assert not snap.copy_dir.exists()


class _Acquire:
    def __init__(self, connection: object) -> None:
        self.connection = connection

    async def __aenter__(self) -> object:
        return self.connection

    async def __aexit__(self, *_args) -> None:
        return None


class _Pool:
    def __init__(self, connection: object) -> None:
        self.connection = connection

    def acquire(self) -> _Acquire:
        return _Acquire(self.connection)


@dataclass
class FakeRepository:
    root: Path
    rows: dict[str, list[dict]]

    @property
    def state_file(self) -> Path:
        return self.root / "B06_Section" / "state.json"


@pytest.fixture
def repository(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> FakeRepository:
    repo = FakeRepository(tmp_path, {"routes": [{"id": 7, "value": "before"}]})
    repo.state_file.parent.mkdir(parents=True)
    repo.state_file.write_text('{"value":"before"}', encoding="utf-8")
    pool = _Pool(repo)

    async def stored_path(_connection, _project_id):
        return "synthetic"

    async def snapshot_rows(_connection, _project_id, surface=False):
        assert surface is False
        return copy.deepcopy(repo.rows)

    async def restore_rows(_connection, _project_id, saved):
        repo.rows = copy.deepcopy(saved)
        return ["routes"]

    monkeypatch.setattr(design, "get_db_pool", lambda: pool)
    monkeypatch.setattr(design, "get_project_storage_relative_path", stored_path)
    monkeypatch.setattr(design, "resolve_stored_project_path", lambda _stored: repo.root)
    monkeypatch.setattr(guard, "snapshot_rows", snapshot_rows)
    monkeypatch.setattr(guard, "restore_rows", restore_rows)
    guard._LOCKS.pop(str(PROJECT), None)
    return repo


def _request() -> design.DesignSaveRequest:
    return design.DesignSaveRequest(route_id=7)


def _body(response) -> dict:
    return json.loads(bytes(response.body).decode("utf-8"))


def test_중간_차례_실패면_repository_storage_그대로(
    repository: FakeRepository, monkeypatch: pytest.MonkeyPatch
) -> None:
    before_rows = copy.deepcopy(repository.rows)
    before_file = repository.state_file.read_bytes()

    async def broken(_project_id, _request, _session):
        repository.rows["routes"][0]["value"] = "half"
        repository.state_file.write_text('{"value":"half"}', encoding="utf-8")
        raise StepFailed("plusStations", "일부러 실패")

    monkeypatch.setattr(design, "_run_steps", broken)
    response = asyncio.run(design.save_design(PROJECT, _request(), None))
    body = _body(response)
    assert response.status_code == 409
    assert body["step"] == "plusStations" and body["restored"] is True
    assert "일부러 실패" in body["message"]
    assert repository.rows == before_rows and repository.state_file.read_bytes() == before_file


def test_정상_한_본문은_모든_차례를_commit(
    repository: FakeRepository, monkeypatch: pytest.MonkeyPatch
) -> None:
    async def complete(_project_id, _request, _session):
        repository.rows["routes"][0]["value"] = "after"
        repository.state_file.write_text('{"value":"after"}', encoding="utf-8")
        return {name: {"status": "success"} for name in ("settings", "plusStations", "cross")}

    monkeypatch.setattr(design, "_run_steps", complete)
    response = asyncio.run(design.save_design(PROJECT, _request(), None))
    body = _body(response)
    assert response.status_code == 200 and body["status"] == "success"
    assert set(body["steps"]) == {"settings", "plusStations", "cross"}
    assert repository.rows["routes"][0]["value"] == "after"
    assert json.loads(repository.state_file.read_text(encoding="utf-8"))["value"] == "after"


def test_되돌림마저_실패면_복구_확인_필요(
    repository: FakeRepository, monkeypatch: pytest.MonkeyPatch
) -> None:
    async def broken(_project_id, _request, _session):
        repository.state_file.write_text("broken", encoding="utf-8")
        raise StepFailed("settings", "설정 실패")

    def no_restore(self):
        raise OSError("디스크 잠김")

    monkeypatch.setattr(design, "_run_steps", broken)
    monkeypatch.setattr(guard.StorageSnapshot, "restore", no_restore)
    response = asyncio.run(design.save_design(PROJECT, _request(), None))
    body = _body(response)
    assert response.status_code == 500
    assert body["restored"] is False and body["step"] == "settings"
    assert "복구 확인 필요" in body["message"]


def test_같은_프로젝트_저장이_겹치면_뒤_요청이_기다림(
    repository: FakeRepository, monkeypatch: pytest.MonkeyPatch
) -> None:
    async def run() -> tuple[dict, dict]:
        entered = asyncio.Event()
        release = asyncio.Event()
        calls = 0

        async def steps(_project_id, _request, _session):
            nonlocal calls
            calls += 1
            if calls == 1:
                entered.set()
                await release.wait()
            return {}

        monkeypatch.setattr(design, "_run_steps", steps)
        first = asyncio.create_task(design.save_design(PROJECT, _request(), None))
        await entered.wait()
        second = asyncio.create_task(design.save_design(PROJECT, _request(), None))
        await asyncio.sleep(0)
        assert not second.done()
        release.set()
        return _body(await first), _body(await second)

    first, second = asyncio.run(run())
    assert first["status"] == second["status"] == "success"
    assert first["waited"] is False and second["waited"] is True