import uuid
from datetime import datetime

from sqlalchemy import DateTime, ForeignKey, Integer, UniqueConstraint, func
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import Mapped, mapped_column

from app.db.base_class import Base


class ImpInventory(Base):
    __tablename__ = "imp_inventory"
    __table_args__ = (UniqueConstraint("study_id", "site_id", "batch_id", name="uq_imp_inventory_site_batch"),)

    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    study_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("studies.id"), index=True, nullable=False)
    site_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("sites.id"), index=True, nullable=False)
    batch_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("imp_batches.id"), index=True, nullable=False)
    quantity_on_hand: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now())