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

from app.db.base import Base
from app.models.document_line_item_version_item import DocumentLineItemVersionItem


class DocumentLineItemSetVersion(Base):
    __tablename__ = "document_line_item_set_versions"
    __table_args__ = (
        UniqueConstraint("document_id", "version_number", name="uq_document_line_item_set_versions_doc_ver"),
    )

    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)
    schema_type: Mapped[str | None] = mapped_column(String(50), 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="line_item_set_versions")
    items: Mapped[list["DocumentLineItemVersionItem"]] = relationship(
        back_populates="set_version",
        cascade="all, delete-orphan",
        order_by="DocumentLineItemVersionItem.line_number",
    )