from src.extensions import db import datetime class CrossReference(db.Model): __tablename__ = 'cross_references' id = db.Column(db.Integer, primary_key=True) source_legislation_id = db.Column(db.Integer, db.ForeignKey('legislation.id'), nullable=False) target_legislation_id = db.Column(db.Integer, db.ForeignKey('legislation.id'), nullable=False) relationship_type = db.Column(db.String, nullable=False) # e.g., 'Cites', 'Amends', 'Conflicts With', 'Related To' details = db.Column(db.Text) # Optional: Specific section or context identified_at = db.Column(db.DateTime, default=datetime.datetime.utcnow) # Prevent duplicate references __table_args__ = (db.UniqueConstraint('source_legislation_id', 'target_legislation_id', 'relationship_type', name='_source_target_rel_uc'),) def __repr__(self): return f''