from django.db.models import Sum

from apps.product import models as product_models


class QuotaDistributionService:
    """
    Service layer to manage multiple quota distributions as one unified entity.
    Used for organization-based views and POS operations.
    """

    def __init__(self, quota, organization):
        self.quota = quota
        self.organization = organization
        self.distribution = product_models.QuotaDistribution.objects.filter(
            quota=quota,
            assigned_organization=organization,
            quota__is_closed=False,
            warehouse_entry__gt=0
        ).first()

        @property
        def total_weight(self):
            return self.distribution.aggregate(
                total=Sum('weight')
            )['total'] or 0

        pass