"""Lease-fenced persistence for the PARSE_DOCUMENT workflow."""

from __future__ import annotations

import hashlib
import json
import re
import uuid
from collections.abc import Callable, Mapping
from dataclasses import dataclass
from typing import Any, Protocol, cast

import psycopg
from psycopg import Connection
from psycopg.rows import dict_row

from app.core.config import Settings
from app.core.secrets import SecretFileError
from app.persistence.job_queue import BackgroundJob, JobLease, LeaseLostError
from app.services.document_ingestion import (
    CloudTextPolicy,
    IngestionArtifact,
    IngestionStatus,
)

type WorkflowRow = dict[str, Any]
type ConnectionFactory = Callable[[str, int], Connection[WorkflowRow]]

_DB_ID_NAMESPACE = uuid.UUID("07fb2c87-b4c9-5dd8-b965-fb5d8e53e350")
_HASH = re.compile(r"^[0-9a-f]{64}$")
_ERROR_CODE = re.compile(r"^[A-Z][A-Z0-9_]{0,127}$")
_NORMALIZATION_PROFILE_HASH = hashlib.sha256(b"document-ingestion-normalized-text-v1").hexdigest()


@dataclass(frozen=True, slots=True)
class DocumentSource:
    upload_id: uuid.UUID
    document_id: uuid.UUID
    knowledge_base_id: uuid.UUID
    access_scope_id: uuid.UUID
    filename: str
    mime_type: str
    storage_key: uuid.UUID
    byte_size: int
    raw_sha256: str


@dataclass(frozen=True, slots=True)
class PlannedPage:
    id: uuid.UUID
    ordinal: int
    page_number: int | None
    text: str
    text_sha256: str
    line_start: int
    line_end: int


@dataclass(frozen=True, slots=True)
class PlannedBlock:
    id: uuid.UUID
    page_id: uuid.UUID
    ordinal: int
    kind: str
    text: str
    text_sha256: str
    section_path: tuple[str, ...]
    anchor_id: str
    normalized_text_sha256: str
    char_start: int
    char_end: int
    line_start: int
    line_end: int
    page_start: int | None
    page_end: int | None


@dataclass(frozen=True, slots=True)
class PlannedChunk:
    id: uuid.UUID
    ordinal: int
    display_text: str
    cloud_text: str
    cloud_text_sha256: str
    embedding_prefix: str
    embedding_text: str
    embedding_text_sha256: str
    token_count: int
    page_start: int | None
    page_end: int | None
    section_path: tuple[str, ...]
    metadata: Mapping[str, object]


@dataclass(frozen=True, slots=True)
class ArtifactPlan:
    version_id: uuid.UUID
    parser_profile_hash: str
    normalization_profile_hash: str
    chunk_profile_hash: str
    cloud_policy_id: str
    outbound_manifest_sha256: str | None
    review_state: str
    version_status: str
    version_error_code: str | None
    expected_chunk_count: int
    document_status: str
    job_stage: str
    pages: tuple[PlannedPage, ...]
    blocks: tuple[PlannedBlock, ...]
    chunks: tuple[PlannedChunk, ...]


class InvalidDocumentJobError(RuntimeError):
    def __init__(self) -> None:
        super().__init__("document job contract is invalid")


class DocumentWorkflowPersistenceError(RuntimeError):
    def __init__(self) -> None:
        super().__init__("document workflow persistence unavailable")


class ArtifactConflictError(RuntimeError):
    def __init__(self) -> None:
        super().__init__("stored ingestion artifact conflicts with deterministic output")


class DocumentWorkflowRepository(Protocol):
    def load_source(self, job: BackgroundJob) -> DocumentSource: ...

    def record_terminal_parse_failure(
        self,
        *,
        lease: JobLease,
        source: DocumentSource,
        error_code: str,
    ) -> None: ...

    def persist_artifact(
        self,
        *,
        lease: JobLease,
        source: DocumentSource,
        artifact: IngestionArtifact,
        cloud_policy: CloudTextPolicy,
        embedding_model: str,
        embedding_dimension: int,
    ) -> ArtifactPlan: ...


LOAD_SOURCE_SQL = """
SELECT
  upload.id AS upload_id,
  upload.document_id,
  upload.knowledge_base_id,
  upload.access_scope_id,
  upload.original_filename,
  upload.declared_mime_type,
  upload.storage_key,
  upload.actual_size,
  upload.actual_sha256,
  document.filename AS document_filename,
  document.mime_type AS document_mime_type,
  document.raw_sha256 AS document_raw_sha256,
  document.storage_key AS document_storage_key
FROM rag.background_jobs AS job
JOIN rag.document_uploads AS upload
  ON upload.parse_job_id = job.id
JOIN rag.documents AS document
  ON document.id = upload.document_id
 AND document.knowledge_base_id = upload.knowledge_base_id
 AND document.access_scope_id = upload.access_scope_id
WHERE job.id = %s
  AND job.status = 'RUNNING'
  AND job.lease_owner = %s
  AND job.lease_token = %s
  AND job.lease_until >= now()
  AND job.job_type = 'PARSE_DOCUMENT'
  AND job.required_capability = 'document_parse'
  AND job.resource_type = 'document'
  AND job.resource_id = %s
  AND upload.id = %s
  AND upload.document_id = %s
  AND upload.status = 'COMPLETED'
  AND upload.actual_size = upload.expected_size
  AND upload.actual_sha256 = upload.expected_sha256
  AND upload.actual_sha256 = document.raw_sha256
  AND upload.storage_key::text = document.storage_key
  AND upload.original_filename = document.filename
  AND upload.declared_mime_type = document.mime_type
  AND document.deleted_at IS NULL
LIMIT 1
"""

FAIL_PARSE_SQL = """
WITH fenced AS (
  SELECT job.id AS job_id, document.id AS document_id
  FROM rag.background_jobs AS job
  JOIN rag.document_uploads AS upload ON upload.parse_job_id = job.id
  JOIN rag.documents AS document
    ON document.id = upload.document_id
   AND document.knowledge_base_id = upload.knowledge_base_id
   AND document.access_scope_id = upload.access_scope_id
  WHERE job.id = %s
    AND job.status = 'RUNNING'
    AND job.lease_owner = %s
    AND job.lease_token = %s
    AND job.lease_until >= now()
    AND job.job_type = 'PARSE_DOCUMENT'
    AND job.required_capability = 'document_parse'
    AND job.resource_type = 'document'
    AND job.resource_id = %s
    AND upload.id = %s
    AND upload.document_id = %s
    AND upload.knowledge_base_id = %s
    AND upload.access_scope_id = %s
    AND upload.actual_size = %s
    AND upload.actual_sha256 = %s
    AND upload.storage_key = %s
    AND upload.status = 'COMPLETED'
    AND document.raw_sha256 = %s
    AND document.storage_key = %s
    AND document.deleted_at IS NULL
  FOR UPDATE OF job, document
), updated_document AS (
  UPDATE rag.documents AS document
  SET status = 'FAILED', updated_at = now()
  FROM fenced
  WHERE document.id = fenced.document_id
  RETURNING document.id
)
UPDATE rag.background_jobs AS job
SET stage = 'PARSE_REJECTED',
    progress = 100,
    last_error_code = %s,
    last_error_message = 'Document parsing was rejected by a deterministic local policy.',
    updated_at = now()
FROM fenced
JOIN updated_document ON updated_document.id = fenced.document_id
WHERE job.id = fenced.job_id
RETURNING job.id
"""

INSERT_VERSION_SQL = """
INSERT INTO rag.document_versions (
  id,
  document_id,
  parser_profile_hash,
  ocr_profile_hash,
  normalization_profile_hash,
  chunk_profile_hash,
  cloud_policy_id,
  outbound_manifest_sha256,
  review_state,
  embedding_profile_hash,
  status,
  expected_chunk_count,
  error_code
) VALUES (%s, %s, %s, NULL, %s, %s, %s, %s, %s, NULL, %s, %s, %s)
ON CONFLICT DO NOTHING
"""

INSERT_PAGE_SQL = """
INSERT INTO rag.document_pages (
  id, document_version_id, ordinal, page_number, display_text, text_sha256,
  line_start, line_end
) VALUES (%s, %s, %s, %s, %s, %s, %s, %s)
ON CONFLICT DO NOTHING
"""

INSERT_BLOCK_SQL = """
INSERT INTO rag.document_blocks (
  id, document_version_id, page_id, ordinal, block_kind, display_text,
  text_sha256, section_path, anchor_id, normalized_text_sha256,
  char_start, char_end, line_start, line_end, page_start, page_end
) VALUES (%s, %s, %s, %s, %s, %s, %s, %s::jsonb, %s, %s, %s, %s, %s, %s, %s, %s)
ON CONFLICT DO NOTHING
"""

INSERT_MANIFEST_ITEM_SQL = """
INSERT INTO rag.outbound_manifest_items (
  document_version_id,
  ordinal,
  outbound_manifest_sha256,
  cloud_text_sha256,
  embedding_text_sha256
) VALUES (%s, %s, %s, %s, %s)
ON CONFLICT DO NOTHING
"""

INSERT_CHUNK_SQL = """
INSERT INTO rag.chunks (
  id,
  knowledge_base_id,
  document_id,
  document_version_id,
  access_scope_id,
  ordinal,
  display_text,
  cloud_text,
  cloud_text_sha256,
  embedding_prefix,
  embedding_text,
  embedding_text_sha256,
  embedded_text_sha256,
  embedding_profile_hash,
  outbound_manifest_sha256,
  token_count,
  page_start,
  page_end,
  section_path,
  metadata,
  embedding_model,
  embedding_dimension,
  embedding,
  approval_status,
  index_status,
  searchable
) VALUES (
  %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s,
  NULL, NULL, %s, %s, %s, %s, %s::jsonb, %s::jsonb, %s, %s, NULL,
  'LOCAL_PARSED_PENDING_CLOUD_REVIEW', 'PENDING', false
)
ON CONFLICT DO NOTHING
"""

SELECT_VERSION_SQL = """
SELECT
  id, document_id, parser_profile_hash, normalization_profile_hash,
  chunk_profile_hash, cloud_policy_id, outbound_manifest_sha256,
  expected_chunk_count
FROM rag.document_versions
WHERE id = %s AND document_id = %s
"""

SELECT_PAGES_SQL = """
SELECT id, ordinal, page_number, display_text, text_sha256, line_start, line_end
FROM rag.document_pages
WHERE document_version_id = %s
ORDER BY ordinal
"""

SELECT_BLOCKS_SQL = """
SELECT
  id, page_id, ordinal, block_kind, display_text, text_sha256, section_path,
  anchor_id, normalized_text_sha256, char_start, char_end, line_start, line_end,
  page_start, page_end
FROM rag.document_blocks
WHERE document_version_id = %s
ORDER BY ordinal
"""

SELECT_MANIFEST_ITEMS_SQL = """
SELECT ordinal, outbound_manifest_sha256, cloud_text_sha256, embedding_text_sha256
FROM rag.outbound_manifest_items
WHERE document_version_id = %s
ORDER BY ordinal
"""

SELECT_CHUNKS_SQL = """
SELECT
  id, ordinal, display_text, cloud_text, cloud_text_sha256, embedding_prefix,
  embedding_text, embedding_text_sha256, token_count, page_start, page_end,
  section_path, metadata
FROM rag.chunks
WHERE document_version_id = %s AND deleted_at IS NULL
ORDER BY ordinal
"""

UPDATE_DOCUMENT_SQL = """
UPDATE rag.documents
SET status = CASE WHEN active_version_id IS NULL THEN %s ELSE status END,
    updated_at = now()
WHERE id = %s
  AND knowledge_base_id = %s
  AND access_scope_id = %s
  AND raw_sha256 = %s
  AND storage_key = %s
  AND deleted_at IS NULL
RETURNING id
"""

FINALIZE_JOB_SQL = """
UPDATE rag.background_jobs AS job
SET stage = %s,
    progress = 100,
    last_error_code = NULL,
    last_error_message = NULL,
    updated_at = now()
WHERE job.id = %s
  AND job.status = 'RUNNING'
  AND job.lease_owner = %s
  AND job.lease_token = %s
  AND job.lease_until >= now()
  AND job.job_type = 'PARSE_DOCUMENT'
  AND job.required_capability = 'document_parse'
  AND job.resource_type = 'document'
  AND job.resource_id = %s
  AND EXISTS (
    SELECT 1
    FROM rag.document_uploads AS upload
    JOIN rag.documents AS document
      ON document.id = upload.document_id
     AND document.knowledge_base_id = upload.knowledge_base_id
     AND document.access_scope_id = upload.access_scope_id
    WHERE upload.parse_job_id = job.id
      AND upload.id = %s
      AND upload.document_id = %s
      AND upload.knowledge_base_id = %s
      AND upload.access_scope_id = %s
      AND upload.actual_size = %s
      AND upload.actual_sha256 = %s
      AND upload.storage_key = %s
      AND upload.status = 'COMPLETED'
      AND document.raw_sha256 = %s
      AND document.storage_key = %s
      AND document.deleted_at IS NULL
  )
RETURNING job.id
"""


class PostgresDocumentWorkflowRepository:
    def __init__(
        self,
        settings: Settings,
        *,
        connect_timeout: int = 5,
        connection_factory: ConnectionFactory | None = None,
    ) -> None:
        self._settings = settings
        self._connect_timeout = connect_timeout
        self._connection_factory = connection_factory or _default_connection_factory

    def _dsn(self) -> str:
        return (
            self._settings.database_url()
            .set(drivername="postgresql")
            .render_as_string(hide_password=False)
        )

    def load_source(self, job: BackgroundJob) -> DocumentSource:
        upload_id, document_id = _validate_job_contract(job)
        parameters = (
            job.id,
            job.lease.worker_id,
            job.lease.lease_token,
            document_id,
            upload_id,
            document_id,
        )
        try:
            with self._connection_factory(self._dsn(), self._connect_timeout) as connection:
                with connection.transaction():
                    row = connection.execute(LOAD_SOURCE_SQL, parameters).fetchone()
        except (OSError, SecretFileError, psycopg.Error):
            raise DocumentWorkflowPersistenceError from None
        if row is None:
            raise LeaseLostError("document source fence is no longer valid")
        source = _source_from_row(row)
        if source.upload_id != upload_id or source.document_id != document_id:
            raise ArtifactConflictError
        return source

    def record_terminal_parse_failure(
        self,
        *,
        lease: JobLease,
        source: DocumentSource,
        error_code: str,
    ) -> None:
        if _ERROR_CODE.fullmatch(error_code) is None:
            raise ValueError("error_code must be a stable uppercase identifier")
        parameters = _fence_parameters(lease, source) + (error_code,)
        try:
            with self._connection_factory(self._dsn(), self._connect_timeout) as connection:
                with connection.transaction():
                    row = connection.execute(FAIL_PARSE_SQL, parameters).fetchone()
                    if row is None:
                        raise LeaseLostError("document failure fence is no longer valid")
        except (OSError, SecretFileError, psycopg.Error):
            raise DocumentWorkflowPersistenceError from None

    def persist_artifact(
        self,
        *,
        lease: JobLease,
        source: DocumentSource,
        artifact: IngestionArtifact,
        cloud_policy: CloudTextPolicy,
        embedding_model: str,
        embedding_dimension: int,
    ) -> ArtifactPlan:
        plan = plan_artifact(
            source,
            artifact,
            cloud_policy=cloud_policy,
        )
        if not embedding_model.strip() or embedding_dimension != 1024:
            raise ArtifactConflictError
        try:
            with self._connection_factory(self._dsn(), self._connect_timeout) as connection:
                with connection.transaction():
                    self._insert_plan(
                        connection,
                        source,
                        plan,
                        embedding_model=embedding_model,
                        embedding_dimension=embedding_dimension,
                    )
                    self._verify_plan(connection, source, plan)
                    document = connection.execute(
                        UPDATE_DOCUMENT_SQL,
                        (
                            plan.document_status,
                            source.document_id,
                            source.knowledge_base_id,
                            source.access_scope_id,
                            source.raw_sha256,
                            str(source.storage_key),
                        ),
                    ).fetchone()
                    if document is None:
                        raise ArtifactConflictError
                    finalized = connection.execute(
                        FINALIZE_JOB_SQL,
                        (plan.job_stage, *_fence_parameters(lease, source)),
                    ).fetchone()
                    if finalized is None:
                        raise LeaseLostError("document artifact fence is no longer valid")
        except (OSError, SecretFileError, psycopg.Error):
            raise DocumentWorkflowPersistenceError from None
        return plan

    @staticmethod
    def _insert_plan(
        connection: Connection[WorkflowRow],
        source: DocumentSource,
        plan: ArtifactPlan,
        *,
        embedding_model: str,
        embedding_dimension: int,
    ) -> None:
        connection.execute(
            INSERT_VERSION_SQL,
            (
                plan.version_id,
                source.document_id,
                plan.parser_profile_hash,
                plan.normalization_profile_hash,
                plan.chunk_profile_hash,
                plan.cloud_policy_id,
                plan.outbound_manifest_sha256,
                plan.review_state,
                plan.version_status,
                plan.expected_chunk_count,
                plan.version_error_code,
            ),
        )
        with connection.cursor() as cursor:
            pages = [
                (
                    page.id,
                    plan.version_id,
                    page.ordinal,
                    page.page_number,
                    page.text,
                    page.text_sha256,
                    page.line_start,
                    page.line_end,
                )
                for page in plan.pages
            ]
            if pages:
                cursor.executemany(INSERT_PAGE_SQL, pages)
            blocks = [
                (
                    block.id,
                    plan.version_id,
                    block.page_id,
                    block.ordinal,
                    block.kind,
                    block.text,
                    block.text_sha256,
                    _json(block.section_path),
                    block.anchor_id,
                    block.normalized_text_sha256,
                    block.char_start,
                    block.char_end,
                    block.line_start,
                    block.line_end,
                    block.page_start,
                    block.page_end,
                )
                for block in plan.blocks
            ]
            if blocks:
                cursor.executemany(INSERT_BLOCK_SQL, blocks)
            if plan.outbound_manifest_sha256 is not None and plan.chunks:
                cursor.executemany(
                    INSERT_MANIFEST_ITEM_SQL,
                    [
                        (
                            plan.version_id,
                            chunk.ordinal,
                            plan.outbound_manifest_sha256,
                            chunk.cloud_text_sha256,
                            chunk.embedding_text_sha256,
                        )
                        for chunk in plan.chunks
                    ],
                )
            chunks = [
                (
                    chunk.id,
                    source.knowledge_base_id,
                    source.document_id,
                    plan.version_id,
                    source.access_scope_id,
                    chunk.ordinal,
                    chunk.display_text,
                    chunk.cloud_text,
                    chunk.cloud_text_sha256,
                    chunk.embedding_prefix,
                    chunk.embedding_text,
                    chunk.embedding_text_sha256,
                    plan.outbound_manifest_sha256,
                    chunk.token_count,
                    chunk.page_start,
                    chunk.page_end,
                    _json(chunk.section_path),
                    _json(chunk.metadata),
                    embedding_model,
                    embedding_dimension,
                )
                for chunk in plan.chunks
            ]
            if chunks:
                cursor.executemany(INSERT_CHUNK_SQL, chunks)

    @staticmethod
    def _verify_plan(
        connection: Connection[WorkflowRow],
        source: DocumentSource,
        plan: ArtifactPlan,
    ) -> None:
        version = connection.execute(
            SELECT_VERSION_SQL, (plan.version_id, source.document_id)
        ).fetchone()
        expected_version = (
            plan.version_id,
            source.document_id,
            plan.parser_profile_hash,
            plan.normalization_profile_hash,
            plan.chunk_profile_hash,
            plan.cloud_policy_id,
            plan.outbound_manifest_sha256,
            plan.expected_chunk_count,
        )
        if version is None or _version_tuple(version) != expected_version:
            raise ArtifactConflictError
        pages = list(connection.execute(SELECT_PAGES_SQL, (plan.version_id,)).fetchall())
        blocks = list(connection.execute(SELECT_BLOCKS_SQL, (plan.version_id,)).fetchall())
        manifests = list(
            connection.execute(SELECT_MANIFEST_ITEMS_SQL, (plan.version_id,)).fetchall()
        )
        chunks = list(connection.execute(SELECT_CHUNKS_SQL, (plan.version_id,)).fetchall())
        if tuple(_page_tuple(row) for row in pages) != tuple(
            _planned_page_tuple(value) for value in plan.pages
        ):
            raise ArtifactConflictError
        if tuple(_block_tuple(row) for row in blocks) != tuple(
            _planned_block_tuple(value) for value in plan.blocks
        ):
            raise ArtifactConflictError
        expected_manifests = (
            tuple(
                (
                    chunk.ordinal,
                    plan.outbound_manifest_sha256,
                    chunk.cloud_text_sha256,
                    chunk.embedding_text_sha256,
                )
                for chunk in plan.chunks
            )
            if plan.outbound_manifest_sha256 is not None
            else ()
        )
        if tuple(_manifest_tuple(row) for row in manifests) != expected_manifests:
            raise ArtifactConflictError
        if tuple(_chunk_tuple(row) for row in chunks) != tuple(
            _planned_chunk_tuple(value) for value in plan.chunks
        ):
            raise ArtifactConflictError


def plan_artifact(
    source: DocumentSource,
    artifact: IngestionArtifact,
    *,
    cloud_policy: CloudTextPolicy,
) -> ArtifactPlan:
    if artifact.raw_sha256 != source.raw_sha256:
        raise ArtifactConflictError
    try:
        source_version_id = uuid.UUID(artifact.document_version_id)
    except ValueError:
        raise ArtifactConflictError from None
    version_id = _namespaced_id(
        "version",
        source.knowledge_base_id,
        source.document_id,
        source_version_id,
    )
    if artifact.status is IngestionStatus.OCR_REQUIRED:
        if artifact.pages or artifact.blocks or artifact.chunks or artifact.manifest is not None:
            raise ArtifactConflictError
        error_code = artifact.limitations[0] if artifact.limitations else "OCR_REQUIRED"
        if _ERROR_CODE.fullmatch(error_code) is None:
            raise ArtifactConflictError
        return ArtifactPlan(
            version_id=version_id,
            parser_profile_hash=_checked_hash(artifact.parser_profile_hash),
            normalization_profile_hash=_NORMALIZATION_PROFILE_HASH,
            chunk_profile_hash=_checked_hash(artifact.chunk_profile_hash),
            cloud_policy_id=cloud_policy.policy_id,
            outbound_manifest_sha256=None,
            review_state="QUARANTINED_LOCAL_REVIEW",
            version_status="PENDING",
            version_error_code=error_code,
            expected_chunk_count=0,
            document_status="LOCAL_OCR_REQUIRED",
            job_stage="OCR_REQUIRED",
            pages=(),
            blocks=(),
            chunks=(),
        )
    if (
        artifact.status is not IngestionStatus.READY_FOR_LOCAL_REVIEW
        or artifact.manifest is None
        or artifact.normalized_text_sha256 is None
        or not artifact.pages
        or not artifact.blocks
        or not artifact.chunks
        or artifact.manifest.cloud_policy_id != cloud_policy.policy_id
        or artifact.manifest.raw_sha256 != source.raw_sha256
        or artifact.manifest.normalized_text_sha256 != artifact.normalized_text_sha256
    ):
        raise ArtifactConflictError

    page_number_ids: dict[int | None, uuid.UUID] = {}
    pages: list[PlannedPage] = []
    for page in artifact.pages:
        page_id = _namespaced_id("page", source.knowledge_base_id, version_id, page.page_id)
        if page.page_number in page_number_ids:
            raise ArtifactConflictError
        page_number_ids[page.page_number] = page_id
        pages.append(
            PlannedPage(
                id=page_id,
                ordinal=page.ordinal,
                page_number=page.page_number,
                text=page.text,
                text_sha256=_checked_hash(page.text_sha256),
                line_start=page.line_start,
                line_end=page.line_end,
            )
        )

    block_ids: dict[str, uuid.UUID] = {}
    blocks: list[PlannedBlock] = []
    for block in artifact.blocks:
        block_id = _namespaced_id("block", source.knowledge_base_id, version_id, block.block_id)
        block_ids[block.block_id] = block_id
        block_page_id = page_number_ids.get(block.anchor.page_start)
        if block_page_id is None:
            raise ArtifactConflictError
        blocks.append(
            PlannedBlock(
                id=block_id,
                page_id=block_page_id,
                ordinal=block.ordinal,
                kind=block.kind.value,
                text=block.text,
                text_sha256=_checked_hash(block.text_sha256),
                section_path=block.section_path,
                anchor_id=_checked_hash(block.anchor.anchor_id),
                normalized_text_sha256=_checked_hash(block.anchor.normalized_text_sha256),
                char_start=block.anchor.char_start,
                char_end=block.anchor.char_end,
                line_start=block.anchor.line_start,
                line_end=block.anchor.line_end,
                page_start=block.anchor.page_start,
                page_end=block.anchor.page_end,
            )
        )

    chunks: list[PlannedChunk] = []
    for chunk in artifact.chunks:
        try:
            remapped_blocks = tuple(str(block_ids[value]) for value in chunk.anchor.block_ids)
        except KeyError:
            raise ArtifactConflictError from None
        chunk_id = _namespaced_id("chunk", source.knowledge_base_id, version_id, chunk.chunk_id)
        chunks.append(
            PlannedChunk(
                id=chunk_id,
                ordinal=chunk.ordinal,
                display_text=chunk.display_text,
                cloud_text=chunk.cloud_text,
                cloud_text_sha256=_checked_hash(chunk.cloud_text_sha256),
                embedding_prefix=chunk.embedding_prefix,
                embedding_text=chunk.embedding_text,
                embedding_text_sha256=_checked_hash(chunk.embedding_text_sha256),
                token_count=chunk.token_count,
                page_start=chunk.anchor.page_start,
                page_end=chunk.anchor.page_end,
                section_path=chunk.section_path,
                metadata={
                    "source_anchor": {
                        "anchor_id": _checked_hash(chunk.anchor.anchor_id),
                        "normalized_text_sha256": _checked_hash(
                            chunk.anchor.normalized_text_sha256
                        ),
                        "char_start": chunk.anchor.char_start,
                        "char_end": chunk.anchor.char_end,
                        "line_start": chunk.anchor.line_start,
                        "line_end": chunk.anchor.line_end,
                        "page_start": chunk.anchor.page_start,
                        "page_end": chunk.anchor.page_end,
                        "block_ids": remapped_blocks,
                    },
                    "ingestion_profile": "document-ingestion-v1",
                },
            )
        )
    if [item.ordinal for item in artifact.manifest.items] != [chunk.ordinal for chunk in chunks]:
        raise ArtifactConflictError
    for item, source_chunk, planned_chunk in zip(
        artifact.manifest.items, artifact.chunks, chunks, strict=True
    ):
        if (
            item.chunk_id != source_chunk.chunk_id
            or item.anchor_id != source_chunk.anchor.anchor_id
            or item.cloud_text_sha256 != planned_chunk.cloud_text_sha256
            or item.embedding_text_sha256 != planned_chunk.embedding_text_sha256
        ):
            raise ArtifactConflictError
    return ArtifactPlan(
        version_id=version_id,
        parser_profile_hash=_checked_hash(artifact.parser_profile_hash),
        normalization_profile_hash=_NORMALIZATION_PROFILE_HASH,
        chunk_profile_hash=_checked_hash(artifact.chunk_profile_hash),
        cloud_policy_id=cloud_policy.policy_id,
        outbound_manifest_sha256=_checked_hash(artifact.manifest.manifest_sha256),
        review_state="LOCAL_PARSED_PENDING_CLOUD_REVIEW",
        version_status="PROCESSING",
        version_error_code=None,
        expected_chunk_count=len(chunks),
        document_status="LOCAL_PARSED_PENDING_CLOUD_REVIEW",
        job_stage="LOCAL_PARSED_PENDING_CLOUD_REVIEW",
        pages=tuple(pages),
        blocks=tuple(blocks),
        chunks=tuple(chunks),
    )


def _validate_job_contract(job: BackgroundJob) -> tuple[uuid.UUID, uuid.UUID]:
    if (
        job.lease.job_id != job.id
        or not job.lease.worker_id.strip()
        or job.job_type != "PARSE_DOCUMENT"
        or job.required_capability != "document_parse"
        or job.resource_type != "document"
        or set(job.payload) != {"upload_id", "document_id"}
    ):
        raise InvalidDocumentJobError
    try:
        upload_id = uuid.UUID(cast(str, job.payload["upload_id"]))
        document_id = uuid.UUID(cast(str, job.payload["document_id"]))
    except (ValueError, TypeError, KeyError):
        raise InvalidDocumentJobError from None
    if document_id != job.resource_id:
        raise InvalidDocumentJobError
    return upload_id, document_id


def _source_from_row(row: Mapping[str, object]) -> DocumentSource:
    source = DocumentSource(
        upload_id=_uuid(row, "upload_id"),
        document_id=_uuid(row, "document_id"),
        knowledge_base_id=_uuid(row, "knowledge_base_id"),
        access_scope_id=_uuid(row, "access_scope_id"),
        filename=_text(row, "original_filename"),
        mime_type=_text(row, "declared_mime_type"),
        storage_key=_uuid(row, "storage_key"),
        byte_size=_integer(row, "actual_size"),
        raw_sha256=_checked_hash(_text(row, "actual_sha256")),
    )
    if (
        _text(row, "document_filename") != source.filename
        or _text(row, "document_mime_type") != source.mime_type
        or _checked_hash(_text(row, "document_raw_sha256")) != source.raw_sha256
        or _text(row, "document_storage_key") != str(source.storage_key)
    ):
        raise ArtifactConflictError
    return source


def _fence_parameters(lease: JobLease, source: DocumentSource) -> tuple[object, ...]:
    return (
        lease.job_id,
        lease.worker_id,
        lease.lease_token,
        source.document_id,
        source.upload_id,
        source.document_id,
        source.knowledge_base_id,
        source.access_scope_id,
        source.byte_size,
        source.raw_sha256,
        source.storage_key,
        source.raw_sha256,
        str(source.storage_key),
    )


def _namespaced_id(kind: str, *parts: object) -> uuid.UUID:
    return uuid.uuid5(_DB_ID_NAMESPACE, "\x1f".join((kind, *(str(value) for value in parts))))


def _checked_hash(value: str) -> str:
    if _HASH.fullmatch(value) is None:
        raise ArtifactConflictError
    return value


def _json(value: object) -> str:
    return json.dumps(value, ensure_ascii=False, sort_keys=True, separators=(",", ":"))


def _default_connection_factory(dsn: str, timeout: int) -> Connection[WorkflowRow]:
    return psycopg.connect(
        dsn,
        connect_timeout=timeout,
        row_factory=dict_row,
        application_name="geological-rag-document-workflow",
    )


def _version_tuple(row: Mapping[str, object]) -> tuple[object, ...]:
    return (
        _uuid(row, "id"),
        _uuid(row, "document_id"),
        _checked_hash(_text(row, "parser_profile_hash")),
        _checked_hash(_text(row, "normalization_profile_hash")),
        _checked_hash(_text(row, "chunk_profile_hash")),
        _text(row, "cloud_policy_id"),
        _optional_hash(row, "outbound_manifest_sha256"),
        _integer(row, "expected_chunk_count"),
    )


def _planned_page_tuple(value: PlannedPage) -> tuple[object, ...]:
    return (
        value.id,
        value.ordinal,
        value.page_number,
        value.text,
        value.text_sha256,
        value.line_start,
        value.line_end,
    )


def _page_tuple(row: Mapping[str, object]) -> tuple[object, ...]:
    return (
        _uuid(row, "id"),
        _integer(row, "ordinal"),
        _optional_integer(row, "page_number"),
        _text(row, "display_text"),
        _checked_hash(_text(row, "text_sha256")),
        _integer(row, "line_start"),
        _integer(row, "line_end"),
    )


def _planned_block_tuple(value: PlannedBlock) -> tuple[object, ...]:
    return (
        value.id,
        value.page_id,
        value.ordinal,
        value.kind,
        value.text,
        value.text_sha256,
        value.section_path,
        value.anchor_id,
        value.normalized_text_sha256,
        value.char_start,
        value.char_end,
        value.line_start,
        value.line_end,
        value.page_start,
        value.page_end,
    )


def _block_tuple(row: Mapping[str, object]) -> tuple[object, ...]:
    return (
        _uuid(row, "id"),
        _uuid(row, "page_id"),
        _integer(row, "ordinal"),
        _text(row, "block_kind"),
        _text(row, "display_text"),
        _checked_hash(_text(row, "text_sha256")),
        _string_tuple(row, "section_path"),
        _checked_hash(_text(row, "anchor_id")),
        _checked_hash(_text(row, "normalized_text_sha256")),
        _integer(row, "char_start"),
        _integer(row, "char_end"),
        _integer(row, "line_start"),
        _integer(row, "line_end"),
        _optional_integer(row, "page_start"),
        _optional_integer(row, "page_end"),
    )


def _manifest_tuple(row: Mapping[str, object]) -> tuple[object, ...]:
    return (
        _integer(row, "ordinal"),
        _checked_hash(_text(row, "outbound_manifest_sha256")),
        _checked_hash(_text(row, "cloud_text_sha256")),
        _checked_hash(_text(row, "embedding_text_sha256")),
    )


def _planned_chunk_tuple(value: PlannedChunk) -> tuple[object, ...]:
    return (
        value.id,
        value.ordinal,
        value.display_text,
        value.cloud_text,
        value.cloud_text_sha256,
        value.embedding_prefix,
        value.embedding_text,
        value.embedding_text_sha256,
        value.token_count,
        value.page_start,
        value.page_end,
        value.section_path,
        _canonical_json(value.metadata),
    )


def _chunk_tuple(row: Mapping[str, object]) -> tuple[object, ...]:
    metadata = row.get("metadata")
    if not isinstance(metadata, dict):
        raise ArtifactConflictError
    return (
        _uuid(row, "id"),
        _integer(row, "ordinal"),
        _text(row, "display_text"),
        _text(row, "cloud_text"),
        _checked_hash(_text(row, "cloud_text_sha256")),
        _text(row, "embedding_prefix"),
        _text(row, "embedding_text"),
        _checked_hash(_text(row, "embedding_text_sha256")),
        _integer(row, "token_count"),
        _optional_integer(row, "page_start"),
        _optional_integer(row, "page_end"),
        _string_tuple(row, "section_path"),
        metadata,
    )


def _canonical_json(value: object) -> object:
    """Match PostgreSQL jsonb's array representation for tuple-backed plans."""

    return json.loads(_json(value))


def _uuid(row: Mapping[str, object], name: str) -> uuid.UUID:
    value = row.get(name)
    if isinstance(value, uuid.UUID):
        return value
    if isinstance(value, str):
        try:
            return uuid.UUID(value)
        except ValueError:
            pass
    raise ArtifactConflictError


def _text(row: Mapping[str, object], name: str) -> str:
    value = row.get(name)
    if not isinstance(value, str) or not value.strip():
        raise ArtifactConflictError
    return value


def _integer(row: Mapping[str, object], name: str) -> int:
    value = row.get(name)
    if isinstance(value, bool) or not isinstance(value, int):
        raise ArtifactConflictError
    return value


def _optional_integer(row: Mapping[str, object], name: str) -> int | None:
    return None if row.get(name) is None else _integer(row, name)


def _optional_hash(row: Mapping[str, object], name: str) -> str | None:
    return None if row.get(name) is None else _checked_hash(_text(row, name))


def _string_tuple(row: Mapping[str, object], name: str) -> tuple[str, ...]:
    value = row.get(name)
    if not isinstance(value, list) or not all(isinstance(item, str) for item in value):
        raise ArtifactConflictError
    return tuple(value)