import threading
from datetime import UTC, datetime, timedelta
from uuid import UUID

from domain.sandbox import SandboxSession, SandboxStatus
from repository.sandbox_lock import ProcessLocalSandboxLifecycleLocker
from repository.sandbox_session import InMemorySandboxSessionRepository
from usecase.sandbox import CleanupExpiredSandboxes, CreateSandbox, CreateSandboxCommand

CHAT_ID = UUID('11111111-1111-1111-1111-111111111111')
NON_CANONICAL_CHAT_ID = '11111111111111111111111111111111'
EXPIRED_CHAT_ID = UUID('22222222-2222-2222-2222-222222222222')
BOUNDARY_CHAT_ID = UUID('33333333-3333-3333-3333-333333333333')
ACTIVE_CHAT_ID = UUID('44444444-4444-4444-4444-444444444444')
FAIL_CHAT_ID = UUID('55555555-5555-5555-5555-555555555555')
CLEAN_CHAT_ID = UUID('66666666-6666-6666-6666-666666666666')
SESSION_REUSED_ID = UUID('00000000-0000-0000-0000-000000000001')
SESSION_OLD_ID = UUID('00000000-0000-0000-0000-000000000002')
SESSION_NEW_ID = UUID('00000000-0000-0000-0000-000000000003')
SESSION_EXPIRED_ID = UUID('00000000-0000-0000-0000-000000000004')
SESSION_BOUNDARY_ID = UUID('00000000-0000-0000-0000-000000000005')
SESSION_ACTIVE_ID = UUID('00000000-0000-0000-0000-000000000006')
SESSION_FAIL_ID = UUID('00000000-0000-0000-0000-000000000007')
SESSION_CLEAN_ID = UUID('00000000-0000-0000-0000-000000000008')
SESSION_REPLACEMENT_ID = UUID('00000000-0000-0000-0000-000000000009')


class FakeClock:
    def __init__(self, now: datetime) -> None:
        self._now = now

    def now(self) -> datetime:
        return self._now


class FakeLogger:
    def __init__(self) -> None:
        self.messages: list[
            tuple[str, str, dict[str, str | int | float | bool] | None]
        ] = []

    def debug(self, message: str, attrs=None) -> None:
        self.messages.append(('debug', message, attrs))

    def info(self, message: str, attrs=None) -> None:
        self.messages.append(('info', message, attrs))

    def warning(self, message: str, attrs=None) -> None:
        self.messages.append(('warning', message, attrs))

    def error(self, message: str, attrs=None) -> None:
        self.messages.append(('error', message, attrs))


class FakeLockContext:
    def __enter__(self) -> None:
        return None

    def __exit__(self, exc_type, exc, traceback) -> None:
        return None


class FakeLocker:
    def __init__(self) -> None:
        self.chat_ids: list[UUID] = []

    def lock(self, chat_id: UUID) -> FakeLockContext:
        self.chat_ids.append(chat_id)
        return FakeLockContext()


class TrackingLockContext:
    def __init__(
        self,
        locker: 'TrackingLocker',
        chat_id: UUID,
        inner_context,
    ) -> None:
        self._locker = locker
        self._chat_id = chat_id
        self._inner_context = inner_context

    def __enter__(self) -> None:
        with self._locker._state_lock:
            self._locker.chat_ids.append(self._chat_id)
            self._locker._attempts += 1
            if self._locker._attempts == 2:
                self._locker.second_attempted.set()

        self._inner_context.__enter__()

    def __exit__(self, exc_type, exc, traceback) -> bool | None:
        return self._inner_context.__exit__(exc_type, exc, traceback)


class TrackingLocker:
    def __init__(self) -> None:
        self._locker = ProcessLocalSandboxLifecycleLocker()
        self._state_lock = threading.Lock()
        self._attempts = 0
        self.second_attempted = threading.Event()
        self.chat_ids: list[UUID] = []

    def lock(self, chat_id: UUID) -> TrackingLockContext:
        return TrackingLockContext(self, chat_id, self._locker.lock(chat_id))


class BlockingCreateRuntime:
    def __init__(self) -> None:
        self.create_calls: list[dict[str, object]] = []
        self.stop_calls: list[str] = []
        self.create_started = threading.Event()
        self.allow_create = threading.Event()

    def create(
        self,
        *,
        session_id: UUID,
        chat_id: UUID,
        created_at: datetime,
        expires_at: datetime,
    ) -> SandboxSession:
        self.create_calls.append(
            {
                'session_id': session_id,
                'chat_id': chat_id,
                'created_at': created_at,
                'expires_at': expires_at,
            }
        )
        self.create_started.set()
        assert self.allow_create.wait(timeout=1)
        return SandboxSession(
            session_id=session_id,
            chat_id=chat_id,
            container_id=f'container-{session_id}',
            status=SandboxStatus.RUNNING,
            created_at=created_at,
            expires_at=expires_at,
        )

    def stop(self, container_id: str) -> None:
        self.stop_calls.append(container_id)


class StaleSnapshotRepository(InMemorySandboxSessionRepository):
    def __init__(self, snapshot: SandboxSession) -> None:
        super().__init__()
        self._snapshot = snapshot

    def list_expired(self, now: datetime) -> list[SandboxSession]:
        return [self._snapshot]


class FakeRuntime:
    def __init__(self) -> None:
        self.create_calls: list[dict[str, object]] = []
        self.stop_calls: list[str] = []

    def create(
        self,
        *,
        session_id: UUID,
        chat_id: UUID,
        created_at: datetime,
        expires_at: datetime,
    ) -> SandboxSession:
        self.create_calls.append(
            {
                'session_id': session_id,
                'chat_id': chat_id,
                'created_at': created_at,
                'expires_at': expires_at,
            }
        )
        return SandboxSession(
            session_id=session_id,
            chat_id=chat_id,
            container_id=f'container-{session_id}',
            status=SandboxStatus.RUNNING,
            created_at=created_at,
            expires_at=expires_at,
        )

    def stop(self, container_id: str) -> None:
        self.stop_calls.append(container_id)


class FailingStopRuntime(FakeRuntime):
    def __init__(self, failing_container_id: str) -> None:
        super().__init__()
        self._failing_container_id = failing_container_id

    def stop(self, container_id: str) -> None:
        self.stop_calls.append(container_id)
        if container_id == self._failing_container_id:
            raise RuntimeError('stop_failed')


def test_create_sandbox_reuses_active_session_when_not_expired() -> None:
    now = datetime(2026, 4, 2, 12, 0, tzinfo=UTC)
    session = SandboxSession(
        session_id=SESSION_REUSED_ID,
        chat_id=CHAT_ID,
        container_id='container-1',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=1),
        expires_at=now + timedelta(minutes=4),
    )
    repository = InMemorySandboxSessionRepository()
    repository.save(session)
    runtime = FakeRuntime()
    logger = FakeLogger()
    locker = FakeLocker()
    usecase = CreateSandbox(
        repository=repository,
        locker=locker,
        runtime=runtime,
        clock=FakeClock(now),
        logger=logger,
        ttl=timedelta(minutes=5),
    )

    result = usecase.execute(CreateSandboxCommand(chat_id=CHAT_ID))

    assert result == session
    assert runtime.create_calls == []
    assert runtime.stop_calls == []
    assert repository.get_active_by_chat_id(CHAT_ID) == session
    assert locker.chat_ids == [CHAT_ID]
    assert logger.messages == [
        (
            'info',
            'sandbox_reused',
            {
                'chat_id': str(CHAT_ID),
                'session_id': str(SESSION_REUSED_ID),
                'container_id': 'container-1',
            },
        )
    ]


def test_create_sandbox_replaces_expired_session_and_creates_new_one(
    monkeypatch,
) -> None:
    now = datetime(2026, 4, 2, 12, 0, tzinfo=UTC)
    expired_session = SandboxSession(
        session_id=SESSION_OLD_ID,
        chat_id=CHAT_ID,
        container_id='container-old',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=10),
        expires_at=now,
    )
    repository = InMemorySandboxSessionRepository()
    repository.save(expired_session)
    runtime = FakeRuntime()
    logger = FakeLogger()
    locker = FakeLocker()
    usecase = CreateSandbox(
        repository=repository,
        locker=locker,
        runtime=runtime,
        clock=FakeClock(now),
        logger=logger,
        ttl=timedelta(minutes=5),
    )
    monkeypatch.setattr('usecase.sandbox._new_session_id', lambda: SESSION_NEW_ID)

    result = usecase.execute(CreateSandboxCommand(chat_id=CHAT_ID))

    assert runtime.stop_calls == ['container-old']
    assert runtime.create_calls == [
        {
            'session_id': SESSION_NEW_ID,
            'chat_id': CHAT_ID,
            'created_at': now,
            'expires_at': now + timedelta(minutes=5),
        }
    ]
    assert result == SandboxSession(
        session_id=SESSION_NEW_ID,
        chat_id=CHAT_ID,
        container_id=f'container-{SESSION_NEW_ID}',
        status=SandboxStatus.RUNNING,
        created_at=now,
        expires_at=now + timedelta(minutes=5),
    )
    assert repository.get_active_by_chat_id(CHAT_ID) == result
    assert locker.chat_ids == [CHAT_ID]
    assert logger.messages == [
        (
            'info',
            'sandbox_replaced',
            {
                'chat_id': str(CHAT_ID),
                'session_id': str(SESSION_OLD_ID),
                'container_id': 'container-old',
            },
        ),
        (
            'info',
            'sandbox_created',
            {
                'chat_id': str(CHAT_ID),
                'session_id': str(SESSION_NEW_ID),
                'container_id': f'container-{SESSION_NEW_ID}',
            },
        ),
    ]


def test_create_sandbox_creates_new_session_when_none_exists() -> None:
    now = datetime(2026, 4, 2, 12, 0, tzinfo=UTC)
    repository = InMemorySandboxSessionRepository()
    runtime = FakeRuntime()
    logger = FakeLogger()
    locker = FakeLocker()
    usecase = CreateSandbox(
        repository=repository,
        locker=locker,
        runtime=runtime,
        clock=FakeClock(now),
        logger=logger,
        ttl=timedelta(minutes=5),
    )

    result = usecase.execute(CreateSandboxCommand(chat_id=UUID(NON_CANONICAL_CHAT_ID)))

    assert result.chat_id == CHAT_ID
    assert result.container_id == f'container-{result.session_id}'
    assert result.status is SandboxStatus.RUNNING
    assert result.created_at == now
    assert result.expires_at == now + timedelta(minutes=5)
    assert len(runtime.create_calls) == 1
    assert runtime.create_calls[0] == {
        'session_id': result.session_id,
        'chat_id': CHAT_ID,
        'created_at': now,
        'expires_at': now + timedelta(minutes=5),
    }
    assert runtime.stop_calls == []
    assert repository.get_active_by_chat_id(CHAT_ID) == result
    assert locker.chat_ids == [CHAT_ID]
    assert logger.messages == [
        (
            'info',
            'sandbox_created',
            {
                'chat_id': str(CHAT_ID),
                'session_id': str(result.session_id),
                'container_id': result.container_id,
            },
        )
    ]


def test_create_sandbox_serializes_duplicate_concurrent_create_for_chat_id(
    monkeypatch,
) -> None:
    now = datetime(2026, 4, 2, 12, 0, tzinfo=UTC)
    repository = InMemorySandboxSessionRepository()
    runtime = BlockingCreateRuntime()
    logger = FakeLogger()
    locker = TrackingLocker()
    usecase = CreateSandbox(
        repository=repository,
        locker=locker,
        runtime=runtime,
        clock=FakeClock(now),
        logger=logger,
        ttl=timedelta(minutes=5),
    )
    monkeypatch.setattr('usecase.sandbox._new_session_id', lambda: SESSION_NEW_ID)

    results: list[SandboxSession | None] = [None, None]
    errors: list[Exception] = []

    def run_create(index: int) -> None:
        try:
            results[index] = usecase.execute(CreateSandboxCommand(chat_id=CHAT_ID))
        except Exception as exc:
            errors.append(exc)

    first_thread = threading.Thread(target=run_create, args=(0,))
    second_thread = threading.Thread(target=run_create, args=(1,))

    first_thread.start()
    assert runtime.create_started.wait(timeout=1)

    second_thread.start()
    assert locker.second_attempted.wait(timeout=1)
    assert len(runtime.create_calls) == 1

    runtime.allow_create.set()

    first_thread.join(timeout=1)
    second_thread.join(timeout=1)

    assert errors == []
    assert results[0] == results[1]
    assert results[0] == SandboxSession(
        session_id=SESSION_NEW_ID,
        chat_id=CHAT_ID,
        container_id=f'container-{SESSION_NEW_ID}',
        status=SandboxStatus.RUNNING,
        created_at=now,
        expires_at=now + timedelta(minutes=5),
    )
    assert len(runtime.create_calls) == 1
    assert runtime.stop_calls == []
    assert repository.get_active_by_chat_id(CHAT_ID) == results[0]
    assert locker.chat_ids == [CHAT_ID, CHAT_ID]
    assert logger.messages == [
        (
            'info',
            'sandbox_created',
            {
                'chat_id': str(CHAT_ID),
                'session_id': str(SESSION_NEW_ID),
                'container_id': f'container-{SESSION_NEW_ID}',
            },
        ),
        (
            'info',
            'sandbox_reused',
            {
                'chat_id': str(CHAT_ID),
                'session_id': str(SESSION_NEW_ID),
                'container_id': f'container-{SESSION_NEW_ID}',
            },
        ),
    ]


def test_cleanup_expired_sandboxes_stops_and_deletes_only_expired_sessions() -> None:
    now = datetime(2026, 4, 2, 12, 0, tzinfo=UTC)
    expired_session = SandboxSession(
        session_id=SESSION_EXPIRED_ID,
        chat_id=EXPIRED_CHAT_ID,
        container_id='container-expired',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=10),
        expires_at=now - timedelta(seconds=1),
    )
    boundary_session = SandboxSession(
        session_id=SESSION_BOUNDARY_ID,
        chat_id=BOUNDARY_CHAT_ID,
        container_id='container-boundary',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=5),
        expires_at=now,
    )
    active_session = SandboxSession(
        session_id=SESSION_ACTIVE_ID,
        chat_id=ACTIVE_CHAT_ID,
        container_id='container-active',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=1),
        expires_at=now + timedelta(minutes=5),
    )
    repository = InMemorySandboxSessionRepository()
    repository.save(expired_session)
    repository.save(boundary_session)
    repository.save(active_session)
    runtime = FakeRuntime()
    logger = FakeLogger()
    locker = FakeLocker()
    usecase = CleanupExpiredSandboxes(
        repository=repository,
        locker=locker,
        runtime=runtime,
        clock=FakeClock(now),
        logger=logger,
    )

    result = usecase.execute()

    assert result == [expired_session, boundary_session]
    assert runtime.stop_calls == ['container-expired', 'container-boundary']
    assert repository.get_active_by_chat_id(EXPIRED_CHAT_ID) is None
    assert repository.get_active_by_chat_id(BOUNDARY_CHAT_ID) is None
    assert repository.get_active_by_chat_id(ACTIVE_CHAT_ID) == active_session
    assert locker.chat_ids == [EXPIRED_CHAT_ID, BOUNDARY_CHAT_ID]
    assert logger.messages == [
        (
            'info',
            'sandbox_cleaned',
            {
                'chat_id': str(EXPIRED_CHAT_ID),
                'session_id': str(SESSION_EXPIRED_ID),
                'container_id': 'container-expired',
            },
        ),
        (
            'info',
            'sandbox_cleaned',
            {
                'chat_id': str(BOUNDARY_CHAT_ID),
                'session_id': str(SESSION_BOUNDARY_ID),
                'container_id': 'container-boundary',
            },
        ),
    ]


def test_cleanup_expired_sandboxes_skips_replaced_session_from_stale_snapshot() -> None:
    now = datetime(2026, 4, 2, 12, 0, tzinfo=UTC)
    expired_snapshot = SandboxSession(
        session_id=SESSION_EXPIRED_ID,
        chat_id=CHAT_ID,
        container_id='container-expired',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=10),
        expires_at=now - timedelta(seconds=1),
    )
    replacement_session = SandboxSession(
        session_id=SESSION_REPLACEMENT_ID,
        chat_id=CHAT_ID,
        container_id='container-new',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(seconds=30),
        expires_at=now + timedelta(minutes=5),
    )
    repository = StaleSnapshotRepository(expired_snapshot)
    repository.save(replacement_session)
    runtime = FakeRuntime()
    logger = FakeLogger()
    locker = FakeLocker()
    usecase = CleanupExpiredSandboxes(
        repository=repository,
        locker=locker,
        runtime=runtime,
        clock=FakeClock(now),
        logger=logger,
    )

    result = usecase.execute()

    assert result == []
    assert runtime.stop_calls == []
    assert repository.get_active_by_chat_id(CHAT_ID) == replacement_session
    assert locker.chat_ids == [CHAT_ID]
    assert logger.messages == []


def test_cleanup_expired_sandboxes_continues_after_stop_failure() -> None:
    now = datetime(2026, 4, 2, 12, 0, tzinfo=UTC)
    failing_session = SandboxSession(
        session_id=SESSION_FAIL_ID,
        chat_id=FAIL_CHAT_ID,
        container_id='container-fail',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=10),
        expires_at=now - timedelta(minutes=1),
    )
    cleaned_session = SandboxSession(
        session_id=SESSION_CLEAN_ID,
        chat_id=CLEAN_CHAT_ID,
        container_id='container-clean',
        status=SandboxStatus.RUNNING,
        created_at=now - timedelta(minutes=9),
        expires_at=now - timedelta(seconds=1),
    )
    repository = InMemorySandboxSessionRepository()
    repository.save(failing_session)
    repository.save(cleaned_session)
    runtime = FailingStopRuntime('container-fail')
    logger = FakeLogger()
    locker = FakeLocker()
    usecase = CleanupExpiredSandboxes(
        repository=repository,
        locker=locker,
        runtime=runtime,
        clock=FakeClock(now),
        logger=logger,
    )

    result = usecase.execute()

    assert result == [cleaned_session]
    assert runtime.stop_calls == ['container-fail', 'container-clean']
    assert repository.get_active_by_chat_id(FAIL_CHAT_ID) == failing_session
    assert repository.get_active_by_chat_id(CLEAN_CHAT_ID) is None
    assert locker.chat_ids == [FAIL_CHAT_ID, CLEAN_CHAT_ID]
    assert logger.messages == [
        (
            'error',
            'sandbox_clean_failed',
            {
                'chat_id': str(FAIL_CHAT_ID),
                'session_id': str(SESSION_FAIL_ID),
                'container_id': 'container-fail',
                'error': 'RuntimeError',
            },
        ),
        (
            'info',
            'sandbox_cleaned',
            {
                'chat_id': str(CLEAN_CHAT_ID),
                'session_id': str(SESSION_CLEAN_ID),
                'container_id': 'container-clean',
            },
        ),
    ]