"""
Explicit share: one user granted access to one set whose visibility
is 'shared'.

Created by: Jess Rogerson (yelling commands at Claude.AI)
"""

from datetime import datetime

from app import db


class SetShare(db.Model):
    """A set shared with a specific user."""

    __tablename__ = 'set_shares'
    __table_args__ = (
        db.UniqueConstraint('set_id', 'user_id', name='uq_set_share'),
    )

    id = db.Column(db.Integer, primary_key=True)
    set_id = db.Column(db.Integer, db.ForeignKey('sets.id', ondelete='CASCADE'),
                       nullable=False, index=True)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id', ondelete='CASCADE'),
                        nullable=False, index=True)
    created_at = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)

    user = db.relationship('User', lazy='joined')

    def __repr__(self):
        return f'<SetShare set={self.set_id} user={self.user_id}>'