from __future__ import annotations
from datetime import datetime, timezone
from sqlalchemy import DateTime, Enum, ForeignKey, Integer, String
from sqlalchemy.orm import Mapped, mapped_column
from .base import Base
from .users import UserRole


class UserInvite(Base):
    """An emailed invitation to make a local account (milestone 496). The link
    carries a one-time key; only its sha256 is stored, as for API tokens. The
    admin chose the role and how many days the link works; the invitee
    chooses their own username, email and password."""
    __tablename__ = "user_invites"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    key_hash: Mapped[str] = mapped_column(String(64), unique=True, nullable=False)
    # Where the invite was sent; the invitee may sign up with another address.
    email: Mapped[str] = mapped_column(String(255), nullable=False)
    role: Mapped[UserRole] = mapped_column(Enum(UserRole), nullable=False, default=UserRole.viewer)
    days: Mapped[int] = mapped_column(Integer, nullable=False, default=7)
    invited_by: Mapped[str | None] = mapped_column(
        String(36), ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, default=lambda: datetime.now(timezone.utc))
    # When the current key was sent; a resend replaces the key and restarts the clock.
    sent_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, default=lambda: datetime.now(timezone.utc))
    expires_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)
    used_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
    used_by: Mapped[str | None] = mapped_column(
        String(36), ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    revoked_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)