from datetime import datetime
from sqlalchemy import String, DateTime, ForeignKey, Text, Integer, BigInteger
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.db.base import Base


class DocumentVersion(Base):
    __tablename__ = "document_versions"

    id: Mapped[int] = mapped_column(primary_key=True, index=True)
    document_id: Mapped[int] = mapped_column(
        ForeignKey("documents.id"), nullable=False, index=True
    )

    version_number: Mapped[int] = mapped_column(Integer, nullable=False)
    version_type: Mapped[str] = mapped_column(
        String(50), nullable=False
    )  # original, corrected_pdf

    file_path: Mapped[str] = mapped_column(Text, nullable=False)
    sha256: Mapped[str | None] = mapped_column(String(64), nullable=True)
    file_size_bytes: Mapped[int | None] = mapped_column(BigInteger, nullable=True)

    created_by: Mapped[str | None] = mapped_column(String(100), nullable=True)
    notes: Mapped[str | None] = mapped_column(Text, nullable=True)

    created_at: Mapped[datetime] = mapped_column(
        DateTime, default=datetime.utcnow, nullable=False
    )

    document: Mapped["Document"] = relationship(back_populates="versions")