import datetime
from sqlalchemy import String, Text, DateTime, Integer, ForeignKey, Boolean
from sqlalchemy.orm import Mapped, mapped_column, relationship
from app.database import Base


class Notification(Base):
    __tablename__ = "notifications"

    id: Mapped[int] = mapped_column(primary_key=True, index=True)
    user_id: Mapped[int] = mapped_column(ForeignKey("users.id", ondelete="CASCADE"), index=True)
    actor_id: Mapped[int | None] = mapped_column(ForeignKey("users.id"), nullable=True)
    notification_type: Mapped[str] = mapped_column(String(50))
    message: Mapped[str] = mapped_column(Text)
    link: Mapped[str | None] = mapped_column(String(500), nullable=True)
    is_read: Mapped[bool] = mapped_column(Boolean, default=False)
    created_at: Mapped[datetime.datetime] = mapped_column(DateTime, default=datetime.datetime.utcnow, index=True)

    user = relationship("User", back_populates="notifications", foreign_keys=[user_id])
    actor = relationship("User", foreign_keys=[actor_id])


class Follow(Base):
    __tablename__ = "follows"

    id: Mapped[int] = mapped_column(primary_key=True, index=True)
    follower_id: Mapped[int] = mapped_column(ForeignKey("users.id", ondelete="CASCADE"), index=True)
    target_type: Mapped[str] = mapped_column(String(50))
    target_id: Mapped[int] = mapped_column(Integer, index=True)
    created_at: Mapped[datetime.datetime] = mapped_column(DateTime, default=datetime.datetime.utcnow)

    follower = relationship("User")