"""Chat message model for tenant AI agent conversations."""
import uuid
from datetime import datetime

from sqlalchemy import String, DateTime, Text, ForeignKey, Integer
from sqlalchemy.orm import Mapped, mapped_column
from sqlalchemy.dialects.postgresql import UUID

from app.database import Base


class ChatMessage(Base):
    __tablename__ = "chat_messages"

    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    tenant_id: Mapped[uuid.UUID | None] = mapped_column(
        UUID(as_uuid=True), ForeignKey("tenants.id", ondelete="CASCADE"), nullable=True, index=True
    )
    user_id: Mapped[uuid.UUID | None] = mapped_column(
        UUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True
    )
    session_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), nullable=False, index=True)
    role: Mapped[str] = mapped_column(String(20), nullable=False)  # "user", "assistant", "system"
    content: Mapped[str] = mapped_column(Text, nullable=False)
    context_type: Mapped[str | None] = mapped_column(String(50), nullable=True)  # "order", "product", "general"
    context_id: Mapped[uuid.UUID | None] = mapped_column(UUID(as_uuid=True), nullable=True)
    token_count: Mapped[int | None] = mapped_column(Integer, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, nullable=False)