accounting/expenses/models.py

from django.db import models
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes.fields import GenericForeignKey
from dateutil.relativedelta import relativedelta


class AuthoringDatesModel(models.Model):
    created_at = models.DateTimeField(auto_now_add=True, null=True)
    modified_at = models.DateTimeField(auto_now=True)

    class Meta:
        abstract = True


class Source(AuthoringDatesModel):
    name = models.CharField(max_length=150)

    def __str__(self):
        return self.name


class OnlineSource(Source):
    url = models.URLField(max_length=200)


class PhysicalSource(Source):
    # TODO auto add coordinates by searching shop address
    latitude = models.FloatField()
    longitude = models.FloatField()


class Category(AuthoringDatesModel):
    name = models.CharField(max_length=150)
    type = models.CharField(
        max_length=20,
        choices=[
            ("Fixed", "Fixed expense"),
            ("Variable", "Variable expense"),
        ],
        default="Variable",
    )
    # Surcharge de la manière d'afficher un objet sensor
    def __str__(self):
        return self.name

    class Meta:
        # db_table = 'book' # Permet de personnaliser le nom de la table en BDD
        verbose_name = "Category"  # Le nom lisbile du modèle
        verbose_name_plural = "Categories"  # Le nom au pluriel du modèle
        ordering = ("name", "type")  # Le tri par défaut dans les listes


class MetaExpense(AuthoringDatesModel):
    category = models.ForeignKey(
        Category,
        related_name="%(app_label)s_%(class)s_related",
        on_delete=models.PROTECT,
    )
    source = models.ForeignKey(
        Source, related_name="%(app_label)s_%(class)s_related", on_delete=models.PROTECT
    )

    class Meta:
        abstract = True


class RawExpense(models.Model):
    name = models.CharField(max_length=150)
    date = models.DateField()
    amount = models.DecimalField(max_digits=10, decimal_places=2)


class LoneExpense(RawExpense, MetaExpense):
    def __str__(self):
        return self.name

    class Meta:
        # db_table = 'book' # Permet de personnaliser le nom de la table en BDD
        verbose_name = "LoneExpense"  # Le nom lisbile du modèle
        verbose_name_plural = "LoneExpenses"  # Le nom au pluriel du modèle
        ordering = ("name", "date", "amount")  # Le tri par défaut dans les listes


class Expense(models.Model):
    object_id = models.PositiveIntegerField()
    content_type = models.ForeignKey(
        ContentType,
        related_name="%(app_label)s_%(class)s_related",
        on_delete=models.CASCADE,
    )
    content_object = GenericForeignKey("content_type", "object_id")
    # Surcharge de la manière d'afficher un objet sensor
    def __str__(self):
        return self.content_object.name

    class Meta:
        # db_table = 'book' # Permet de personnaliser le nom de la table en BDD
        verbose_name = "Expense"  # Le nom lisbile du modèle
        verbose_name_plural = "Expenses"  # Le nom au pluriel du modèle
        """ ordering = ("name", "date", "amount")  # Le tri par défaut dans les listes """


class MultiplePaymentExepense(LoneExpense):
    payments = models.ManyToManyField(
        RawExpense, related_name="multiple_payment_expense"
    )
    number_of_payment = models.PositiveIntegerField()

    def set_payments(self, payment):
        payment.date = self.date
        payment.name = self.name + " 1st payment"

        payment.save()

        self.payments.add(payment)
        rest_to_pay = (self.amount - payment.amount) / (self.number_of_payment - 1)
        for i in range(1, self.number_of_payment):
            date = self.date + relativedelta(months=i)
            payment = RawExpense(
                name=f"{self.name} {i} payment", date=date, amount=rest_to_pay
            )
            payment.save()
            self.payments.add(payment)
        self.save()
        print(self.payments.count())

    def __str__(self):
        return self.name

    class Meta:
        # db_table = 'book' # Permet de personnaliser le nom de la table en BDD
        verbose_name = "MultiplePaymentExpense"  # Le nom lisbile du modèle
        verbose_name_plural = "MultiplePaymentExpenses"  # Le nom au pluriel du modèle
        ordering = ("name", "date", "amount")