from sqlalchemy import Boolean, ForeignKey, String, Text, Index
from sqlalchemy.orm import Mapped, mapped_column

from app.models.base import Base, TimestampMixin


class Notification(Base, TimestampMixin):
    __tablename__ = "notifications"

    id: Mapped[str] = mapped_column(String(32), primary_key=True)
    user_id: Mapped[str | None] = mapped_column(
        String(32), ForeignKey("users.id", ondelete="CASCADE"), nullable=True, index=True
    )
    title: Mapped[str] = mapped_column(String(128))
    content: Mapped[str] = mapped_column(Text)
    type: Mapped[str] = mapped_column(String(32), default="system")
    is_read: Mapped[bool] = mapped_column(Boolean, default=False)
    related_id: Mapped[str | None] = mapped_column(String(64), nullable=True)

    __table_args__ = (
        Index('idx_notif_user_isread_created', 'user_id', 'is_read', 'created_at'),
    )