from sqlalchemy import JSON, Column, DateTime, ForeignKey, Integer, String, UniqueConstraint
from sqlalchemy.sql import func

from app.db.session import Base


class PlaygroundSession(Base):
    __tablename__ = "playground_sessions"
    __table_args__ = (
        UniqueConstraint("user_id", "session_key", name="uq_playground_sessions_user_session_key"),
    )

    id = Column(Integer, primary_key=True, autoincrement=True)
    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
    session_key = Column(String(100), nullable=False, default="default")
    title = Column(String(200), nullable=False, default="Playground 会话")
    state = Column(JSON, nullable=False, default={})
    created_at = Column(DateTime(timezone=True), server_default=func.now(), nullable=False)
    updated_at = Column(
        DateTime(timezone=True),
        server_default=func.now(),
        onupdate=func.now(),
        nullable=False,
    )

    def __repr__(self):
        return f"<PlaygroundSession user_id={self.user_id} session_key={self.session_key}>"