"""知识库分块向量模型。"""

from __future__ import annotations

from typing import Any, Optional

from sqlalchemy import BigInteger, ForeignKey, Integer, Text, VARCHAR
from sqlalchemy.orm import Mapped, mapped_column

from .base import Base
from .types import JSONB, Vector


class KnowledgeBaseChunk(Base):
    __tablename__ = "knowledge_base_chunks"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    doc_id: Mapped[Optional[int]] = mapped_column(
        Integer,
        ForeignKey("knowledge_base_docs.id", ondelete="CASCADE"),
        nullable=True,
        index=True,
    )
    source_type: Mapped[str] = mapped_column(VARCHAR(32), nullable=False, default="doc", index=True)
    project_id: Mapped[Optional[int]] = mapped_column(BigInteger, nullable=True, index=True)
    content: Mapped[str] = mapped_column(Text, nullable=False)
    embedding: Mapped[Optional[Any]] = mapped_column(Vector(768), nullable=True)
    chunk_index: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    chunk_metadata: Mapped[Optional[Any]] = mapped_column("metadata", JSONB, nullable=True)