import uuid
from datetime import datetime

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

from app.db.base_class import Base


class WorkflowNode(Base):
    __tablename__ = "workflow_nodes"
    __table_args__ = (UniqueConstraint("template_id", "node_order", name="uq_workflow_nodes_order"),)

    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    template_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("workflow_templates.id"), nullable=False)
    node_order: Mapped[int] = mapped_column(Integer, nullable=False)
    role: Mapped[str] = mapped_column(String(50), nullable=False)
    name: Mapped[str | None] = mapped_column(String(100), nullable=True)
    is_required: Mapped[bool] = mapped_column(Boolean, nullable=False, server_default="true")
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())

    template = relationship("WorkflowTemplate", back_populates="nodes")