from datetime import datetime
from typing import Optional

from sqlalchemy import DateTime, ForeignKey, String, func
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.core.database import Base


class Conversation(Base):
    __tablename__ = "conversations"

    id: Mapped[str] = mapped_column(String(64), primary_key=True)
    product_id: Mapped[str] = mapped_column(ForeignKey("products.id"), nullable=False)
    character_id: Mapped[str] = mapped_column(ForeignKey("characters.id"), nullable=False)
    status: Mapped[str] = mapped_column(String(32), default="active")
    device_id: Mapped[Optional[str]] = mapped_column(String(128), nullable=True)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), server_default=func.now()
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), server_default=func.now(), onupdate=func.now()
    )

    product = relationship("Product", back_populates="conversations")
    character = relationship("Character", back_populates="conversations")
    messages = relationship(
        "ConversationMessage",
        back_populates="conversation",
        order_by="ConversationMessage.created_at",
        cascade="all, delete-orphan",
    )