"""SQLite-backed resilience tests for ``clean_document_task``.

The task must continue PostgreSQL cleanup when vector cleanup fails. Each test
starts from the production incident shape: the caller has already deleted the
``Document`` row while its segments and metadata bindings remain.
"""

import uuid
from datetime import UTC, datetime, timedelta
from unittest.mock import patch

import pytest
from sqlalchemy import select
from sqlalchemy.orm import Session

import tasks.clean_document_task as clean_document_task_module
from extensions.storage.storage_type import StorageType
from models.dataset import (
    Dataset,
    DatasetMetadataBinding,
    Document,
    DocumentSegment,
    SegmentAttachmentBinding,
)
from models.enums import CreatorUserRole, DataSourceType
from models.knowledge_fs import KnowledgeFSUpgradeFileLease, KnowledgeFSUpgradeJob
from models.model import UploadFile
from tasks.clean_document_task import clean_document_task
from tests.helpers.unit.model_factories import make_document

SQLITE_MODELS = (
    Dataset,
    Document,
    DocumentSegment,
    SegmentAttachmentBinding,
    UploadFile,
    DatasetMetadataBinding,
)

pytestmark = pytest.mark.parametrize("sqlite_session", [SQLITE_MODELS], indirect=True)


@pytest.fixture
def document_id() -> str:
    return str(uuid.uuid4())


@pytest.fixture
def dataset_id() -> str:
    return str(uuid.uuid4())


@pytest.fixture
def tenant_id() -> str:
    return str(uuid.uuid4())


@pytest.fixture
def bind_task_sessions(monkeypatch: pytest.MonkeyPatch, sqlite_session: Session) -> None:
    """Bind every short-lived task transaction to the isolated SQLite engine."""
    engine = sqlite_session.get_bind()
    monkeypatch.setattr(
        clean_document_task_module.session_factory,
        "create_session",
        lambda: Session(engine, expire_on_commit=False),
    )


@pytest.fixture
def mock_storage():
    with patch("tasks.clean_document_task.storage", autospec=True) as mock:
        mock.delete.return_value = None
        yield mock


@pytest.fixture
def mock_index_cleanup(tenant_id: str):
    """Keep task resilience tests independent of the external index backend."""
    with patch("tasks.clean_document_task.clean_document_indexes", return_value=tenant_id) as cleanup:
        yield cleanup


def _document(*, document_id: str, dataset_id: str, tenant_id: str, created_by: str) -> Document:
    return make_document(
        document_id=document_id,
        tenant_id=tenant_id,
        dataset_id=dataset_id,
        name=f"{document_id}.txt",
        created_by=created_by,
    )


def _segment(*, segment_id: str, document_id: str, dataset_id: str, tenant_id: str, created_by: str) -> DocumentSegment:
    segment = DocumentSegment(
        tenant_id=tenant_id,
        dataset_id=dataset_id,
        document_id=document_id,
        position=1,
        content="segment content",
        word_count=2,
        tokens=2,
        created_by=created_by,
        index_node_id=f"node-{segment_id}",
    )
    segment.id = segment_id
    return segment


def _persist_deleted_document_state(
    session: Session,
    *,
    document_id: str,
    dataset_id: str,
    tenant_id: str,
    target_segment_ids: list[str],
) -> tuple[str, str]:
    """Persist target children after deleting their document, plus scoped control rows."""
    created_by = str(uuid.uuid4())
    other_document_id = str(uuid.uuid4())
    survivor_segment_id = str(uuid.uuid4())
    dataset = Dataset(
        id=dataset_id,
        tenant_id=tenant_id,
        name="Cleanup dataset",
        data_source_type=DataSourceType.UPLOAD_FILE,
        created_by=created_by,
    )
    target_document = _document(
        document_id=document_id,
        dataset_id=dataset_id,
        tenant_id=tenant_id,
        created_by=created_by,
    )
    other_document = _document(
        document_id=other_document_id,
        dataset_id=dataset_id,
        tenant_id=tenant_id,
        created_by=created_by,
    )
    segments = [
        _segment(
            segment_id=segment_id,
            document_id=document_id,
            dataset_id=dataset_id,
            tenant_id=tenant_id,
            created_by=created_by,
        )
        for segment_id in target_segment_ids
    ]
    segments.append(
        _segment(
            segment_id=survivor_segment_id,
            document_id=other_document_id,
            dataset_id=dataset_id,
            tenant_id=tenant_id,
            created_by=created_by,
        )
    )
    metadata_bindings = [
        DatasetMetadataBinding(
            tenant_id=tenant_id,
            dataset_id=dataset_id,
            metadata_id=str(uuid.uuid4()),
            document_id=current_document_id,
            created_by=created_by,
        )
        for current_document_id in (document_id, other_document_id)
    ]

    session.add_all([dataset, target_document, other_document, *segments, *metadata_bindings])
    session.commit()
    session.delete(target_document)
    session.commit()
    return other_document_id, survivor_segment_id


def _assert_relational_cleanup(
    session: Session,
    *,
    document_id: str,
    other_document_id: str,
    survivor_segment_id: str,
) -> None:
    session.expire_all()
    assert session.get(Document, document_id) is None
    remaining_segments = session.scalars(select(DocumentSegment)).all()
    assert [(segment.id, segment.document_id) for segment in remaining_segments] == [
        (survivor_segment_id, other_document_id)
    ]
    remaining_binding_document_ids = set(session.scalars(select(DatasetMetadataBinding.document_id)).all())
    assert remaining_binding_document_ids == {other_document_id}


class TestVectorCleanupResilience:
    """Vector/index failures must not abort relational cleanup."""

    def test_billing_failure_during_vector_cleanup_does_not_skip_pg_cleanup(
        self,
        document_id: str,
        dataset_id: str,
        tenant_id: str,
        sqlite_session: Session,
        bind_task_sessions: None,
        mock_storage,
        mock_index_cleanup,
    ) -> None:
        """A transient billing failure leaves only the unrelated document's rows."""
        other_document_id, survivor_segment_id = _persist_deleted_document_state(
            sqlite_session,
            document_id=document_id,
            dataset_id=dataset_id,
            tenant_id=tenant_id,
            target_segment_ids=["seg-1", "seg-2"],
        )
        mock_index_cleanup.side_effect = ValueError(
            "Unable to retrieve billing information. Please try again later or contact support."
        )

        # Act — must not raise out of the task even though clean() raises.
        with patch("tasks.clean_document_task.schedule_billing_vector_space_refresh") as schedule_refresh:
            clean_document_task(
                document_id=document_id,
                dataset_id=dataset_id,
                doc_form="paragraph",
                file_id=None,
            )

        mock_index_cleanup.assert_called_once()
        _assert_relational_cleanup(
            sqlite_session,
            document_id=document_id,
            other_document_id=other_document_id,
            survivor_segment_id=survivor_segment_id,
        )
        schedule_refresh.assert_not_called()


def test_active_upgrade_lease_keeps_the_legacy_source_file(
    document_id: str,
    dataset_id: str,
    tenant_id: str,
    sqlite_session: Session,
    bind_task_sessions: None,
    mock_storage,
    mock_index_cleanup,
) -> None:
    del bind_task_sessions, mock_index_cleanup
    _persist_deleted_document_state(
        sqlite_session,
        document_id=document_id,
        dataset_id=dataset_id,
        tenant_id=tenant_id,
        target_segment_ids=[],
    )
    account_id = str(uuid.uuid4())
    upload_file = UploadFile(
        tenant_id=tenant_id,
        storage_type=StorageType.LOCAL,
        key=f"upload_files/{tenant_id}/source.txt",
        name="source.txt",
        size=12,
        extension="txt",
        mime_type="text/plain",
        created_by_role=CreatorUserRole.ACCOUNT,
        created_by=account_id,
        created_at=datetime(2026, 8, 17, tzinfo=UTC),
        used=False,
    )
    now = datetime.now(UTC).replace(tzinfo=None)
    job = KnowledgeFSUpgradeJob(
        tenant_id=tenant_id,
        old_dataset_id=dataset_id,
        requested_by_account_id=account_id,
        owner_account_id=account_id,
        idempotency_key="cleanup-lease-test",
        snapshot_at=now,
        config_snapshot={},
        permission_snapshot={},
        app_binding_snapshot=[],
        tag_ids_snapshot=[],
    )
    sqlite_session.add_all([upload_file, job])
    sqlite_session.flush()
    lease = KnowledgeFSUpgradeFileLease(
        job_id=job.id,
        old_upload_file_id=upload_file.id,
        expires_at=now + timedelta(hours=1),
    )
    sqlite_session.add(lease)
    sqlite_session.commit()

    clean_document_task(
        document_id=document_id,
        dataset_id=dataset_id,
        doc_form="paragraph",
        file_id=upload_file.id,
    )

    sqlite_session.expire_all()
    assert sqlite_session.get(UploadFile, upload_file.id) is not None
    persisted_lease = sqlite_session.get(KnowledgeFSUpgradeFileLease, lease.id)
    assert persisted_lease is not None
    assert persisted_lease.cleanup_requested_at is not None
    mock_storage.delete.assert_not_called()


class TestVectorCleanupSuccessPaths:
    def test_vector_cleanup_success_path_remains_unaffected(
        self,
        document_id: str,
        dataset_id: str,
        tenant_id: str,
        sqlite_session: Session,
        bind_task_sessions: None,
        mock_storage,
        mock_index_cleanup,
    ) -> None:
        """The happy path calls the index boundary and completes scoped cleanup."""
        other_document_id, survivor_segment_id = _persist_deleted_document_state(
            sqlite_session,
            document_id=document_id,
            dataset_id=dataset_id,
            tenant_id=tenant_id,
            target_segment_ids=["seg-1"],
        )

        with patch("tasks.clean_document_task.schedule_billing_vector_space_refresh") as schedule_refresh:
            clean_document_task(
                document_id=document_id,
                dataset_id=dataset_id,
                doc_form="paragraph",
                file_id=None,
            )

        mock_index_cleanup.assert_called_once()
        _, kwargs = mock_index_cleanup.call_args
        new_session = kwargs.pop("new_session")
        with new_session() as cleanup_session:
            assert cleanup_session.get_bind() is sqlite_session.get_bind()
        assert kwargs == {
            "dataset_id": dataset_id,
            "document_ids": [document_id],
            "doc_form": "paragraph",
        }
        _assert_relational_cleanup(
            sqlite_session,
            document_id=document_id,
            other_document_id=other_document_id,
            survivor_segment_id=survivor_segment_id,
        )
        schedule_refresh.assert_called_once_with(tenant_id)

    def test_no_index_state_does_not_refresh_billing(
        self,
        document_id: str,
        dataset_id: str,
        tenant_id: str,
        sqlite_session: Session,
        bind_task_sessions: None,
        mock_storage,
        mock_index_cleanup,
    ) -> None:
        """Cleanup checks for orphan summaries even when no segments remain."""
        mock_index_cleanup.return_value = None
        other_document_id, survivor_segment_id = _persist_deleted_document_state(
            sqlite_session,
            document_id=document_id,
            dataset_id=dataset_id,
            tenant_id=tenant_id,
            target_segment_ids=[],
        )

        with patch("tasks.clean_document_task.schedule_billing_vector_space_refresh") as schedule_refresh:
            clean_document_task(
                document_id=document_id,
                dataset_id=dataset_id,
                doc_form="paragraph",
                file_id=None,
            )

        mock_index_cleanup.assert_called_once()
        _assert_relational_cleanup(
            sqlite_session,
            document_id=document_id,
            other_document_id=other_document_id,
            survivor_segment_id=survivor_segment_id,
        )
        schedule_refresh.assert_not_called()