expephalon/core/models/invoices.py

from django.db.models import Model, ForeignKey, CASCADE, PositiveIntegerField, TextField, BooleanField, DateField, SET_NULL, PROTECT

from core.fields.base import LongCharField
from core.fields.numbers import CostField
from core.models.profiles import ClientProfile
from core.models.local import Currency
from core.models.brands import Brand

class Invoice(Model):
    client = ForeignKey(ClientProfile, on_delete=PROTECT)
    brand = ForeignKey(Brand, on_delete=PROTECT)
    number = LongCharField()
    created = DateField()
    due = DateField()
    payment_method = LongCharField()
    currency = ForeignKey(Currency, on_delete=PROTECT)

class InvoiceItem(Model):
    from core.models.services import Service
    from core.models.billable import Billable

    invoice = ForeignKey(Invoice, on_delete=CASCADE)
    sort = PositiveIntegerField()
    name = LongCharField()
    description = TextField(blank=True, null=True)
    price = CostField()
    discount = CostField()
    taxable = BooleanField()
    service = ForeignKey(Service, on_delete=SET_NULL, null=True)
    billable = ForeignKey(Billable, on_delete=SET_NULL, null=True)