from __future__ import annotations

from datetime import UTC, datetime
from typing import Any

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

from app.models.base import BaseModel, ID_TYPE, TimestampMixin


class ShareLink(BaseModel, TimestampMixin):
    __tablename__ = "share_links"
    __table_args__ = (
        UniqueConstraint("token", name="uk_share_links_token"),
        Index("idx_share_links_expires_at", "expires_at"),
        Index("idx_share_links_revoked_at", "revoked_at"),
        Index("idx_share_links_created_by", "created_by"),
        Index("idx_share_links_updated_at", "updated_at"),
    )

    id: Mapped[int] = mapped_column(ID_TYPE, primary_key=True)
    token: Mapped[str] = mapped_column(String(64), nullable=False)
    label: Mapped[str | None] = mapped_column(String(128), nullable=True)
    expires_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)
    revoked_at: Mapped[datetime | None] = mapped_column(DateTime, nullable=True)
    created_by: Mapped[int | None] = mapped_column(
        ID_TYPE,
        ForeignKey("accounts.id", ondelete="SET NULL"),
        nullable=True,
    )

    creator: Mapped[Any] = relationship(
        "Account",
        foreign_keys=[created_by],
        back_populates="created_share_links",
    )

    @property
    def is_revoked(self) -> bool:
        return self.revoked_at is not None

    def is_expired(self, *, now: datetime | None = None) -> bool:
        current = now or datetime.now(UTC).replace(tzinfo=None)
        return self.expires_at <= current

    def is_active(self, *, now: datetime | None = None) -> bool:
        return not self.is_revoked and not self.is_expired(now=now)