from sqlalchemy.orm import Session
from . import models, dto

"""
Service layer for FractionRuleOctave.
"""

class FractionRuleOctaveService:
    @staticmethod
    def get_fraction_by_permission_line(db: Session, permission: str, line: int, fraction: str):
        return db.query(models.FractionRuleOctave).filter(
            models.FractionRuleOctave.permission == permission,
            models.FractionRuleOctave.line == line,
            models.FractionRuleOctave.fraction == fraction
        ).first()

    @staticmethod
    def create_frac(db: Session, frac_data: dto.FractionRuleOctaveCreateDTO):
        new_frac = models.FractionRuleOctave(**frac_data.model_dump())
        db.add(new_frac)
        db.commit()
        db.refresh(new_frac)
        return new_frac

    @staticmethod
    def delete_fraction(db: Session, permission: str, line: int, fraction: str):
        frac = FractionRuleOctaveService.get_fraction_by_permission_line(db, permission, line, fraction)
        if frac:
            db.delete(frac)
            db.commit()
        return frac