from datetime import datetime, timezone
from typing import Any, Optional

from sqlalchemy import JSON, DateTime, String, Text
from sqlalchemy.orm import Mapped, mapped_column

from app.db import Base


class Message(Base):
    __tablename__ = "messages"

    id: Mapped[str] = mapped_column(String(64), primary_key=True)
    tenant_id: Mapped[str] = mapped_column(String(64), nullable=False, index=True)
    conversation_id: Mapped[str] = mapped_column(String(64), nullable=False, index=True)
    user_id: Mapped[Optional[str]] = mapped_column(String(64), nullable=True)
    role: Mapped[str] = mapped_column(String(20), nullable=False)
    content: Mapped[str] = mapped_column(Text, nullable=False)
    sources_json: Mapped[Optional[list[dict[str, Any]]]] = mapped_column(JSON, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=lambda: datetime.now(timezone.utc), index=True)