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


class ExchangeRateService:
    @staticmethod
    def get_exchange_rate_by_date(db: Session, date: int):
        return (
            db.query(models.ExchangeRate)
            .filter(models.ExchangeRate.date == date)
            .first()
        )

    @staticmethod
    def create_exchange_rate(
        db: Session, exchange_rate_data: dto.ExchangeRateCreateDTO
    ):
        new_exchange_rate = models.ExchangeRate(**exchange_rate_data.dict())
        db.add(new_exchange_rate)
        db.commit()
        db.refresh(new_exchange_rate)
        return new_exchange_rate

    @staticmethod
    def delete_exchange_rate(db: Session, date: int):
        exchange_rate = ExchangeRateService.get_exchange_rate_by_date(db, date)
        if exchange_rate:
            db.delete(exchange_rate)
            db.commit()
        return exchange_rate