nummi/nummi/main/models.py

import datetime
import pathlib
import uuid

from django.conf import settings
from django.core.validators import FileExtensionValidator
from django.db import models, transaction
from django.forms import ModelForm
from django.urls import reverse
from django.utils.translation import gettext as _


class UserModel(models.Model):
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        verbose_name=_("User"),
        editable=False,
    )

    class Meta:
        abstract = True


class CustomModel(UserModel):
    @property
    def adding(self):
        return self._state.adding

    class Meta:
        abstract = True


class Account(CustomModel):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    name = models.CharField(max_length=64, default=_("Account"), verbose_name=_("Name"))
    icon = models.CharField(
        max_length=64, default="building-columns", verbose_name=_("Icon")
    )

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse("account", kwargs={"pk": self.pk})

    def get_delete_url(self):
        return reverse("del_account", kwargs={"pk": self.pk})

    @property
    def transactions(self):
        return Transaction.objects.filter(account=self)

    @property
    def snapshots(self):
        return Snapshot.objects.filter(account=self)

    class Meta:
        ordering = ["name"]
        verbose_name = _("Account")
        verbose_name_plural = _("Accounts")


class AccountModel(CustomModel):
    account = models.ForeignKey(
        Account,
        on_delete=models.CASCADE,
        verbose_name=_("Account"),
    )

    class Meta:
        abstract = True


class Category(CustomModel):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    name = models.CharField(
        max_length=64, default=_("Category"), verbose_name=_("Name")
    )
    icon = models.CharField(max_length=64, default="folder", verbose_name=_("Icon"))
    budget = models.BooleanField(default=True, verbose_name=_("Budget"))

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse("category", kwargs={"pk": self.pk})

    def get_delete_url(self):
        return reverse("del_category", kwargs={"pk": self.pk})

    @property
    def transactions(self):
        return Transaction.objects.filter(category=self)

    class Meta:
        ordering = ["name"]
        verbose_name = _("Category")
        verbose_name_plural = _("Categories")


def snapshot_path(instance, filename):
    return pathlib.Path("snapshots", str(instance.id)).with_suffix(".pdf")


class Snapshot(AccountModel):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    date = models.DateField(default=datetime.date.today, verbose_name=_("End date"))
    start_date = models.DateField(
        default=datetime.date.today, verbose_name=_("Start date")
    )
    value = models.DecimalField(
        max_digits=12, decimal_places=2, default=0, verbose_name=_("End value")
    )
    start_value = models.DecimalField(
        max_digits=12, decimal_places=2, default=0, verbose_name=_("Start value")
    )
    diff = models.DecimalField(
        max_digits=12,
        decimal_places=2,
        default=0,
        verbose_name=_("Difference"),
        editable=False,
    )
    sum = models.DecimalField(
        max_digits=12,
        decimal_places=2,
        default=0,
        verbose_name=_("Transaction difference"),
        editable=False,
    )
    file = models.FileField(
        upload_to=snapshot_path,
        validators=[FileExtensionValidator(["pdf"])],
        verbose_name=_("File"),
        max_length=256,
        blank=True,
        default="",
    )

    def __str__(self):
        return _("%(date)s statement") % {"date": self.date}

    def save(self, *args, **kwargs):
        if Snapshot.objects.filter(id=self.id).exists():
            _prever = Snapshot.objects.get(id=self.id)
            if _prever.file and _prever.file != self.file:
                pathlib.Path(_prever.file.path).unlink(missing_ok=True)

        with transaction.atomic():
            for trans in self.transaction_set.all():
                trans.save()

        self.diff = self.value - self.start_value
        super().save(*args, **kwargs)

    def update_sum(self):
        self.sum = self.transaction_set.aggregate(sum=models.Sum("value")).get("sum", 0)
        super().save()

    def delete(self, *args, only_super=False, **kwargs):
        if self.file:
            self.file.delete()

    def get_absolute_url(self):
        return reverse("snapshot", kwargs={"pk": self.pk})

    def get_delete_url(self):
        return reverse("del_snapshot", kwargs={"pk": self.pk})

    class Meta:
        ordering = ["-date"]
        verbose_name = _("Statement")
        verbose_name_plural = _("Statements")


class Transaction(CustomModel):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    name = models.CharField(
        max_length=256, default=_("Transaction"), verbose_name=_("Name")
    )
    description = models.TextField(null=True, blank=True, verbose_name=_("Description"))
    value = models.DecimalField(
        max_digits=12, decimal_places=2, default=0, verbose_name=_("Value")
    )
    date = models.DateField(default=datetime.date.today, verbose_name=_("Date"))
    real_date = models.DateField(blank=True, null=True, verbose_name=_("Real date"))
    trader = models.CharField(
        max_length=128, blank=True, null=True, verbose_name=_("Trader")
    )
    payment = models.CharField(
        max_length=128, blank=True, null=True, verbose_name=_("Payment")
    )
    category = models.ForeignKey(
        Category,
        on_delete=models.SET_NULL,
        blank=True,
        null=True,
        verbose_name=_("Category"),
    )
    snapshot = models.ForeignKey(
        Snapshot,
        on_delete=models.CASCADE,
        verbose_name=_("Statement"),
    )
    account = models.ForeignKey(
        Account,
        on_delete=models.CASCADE,
        verbose_name=_("Account"),
        editable=False,
    )

    def save(self, *args, **kwargs):
        self.account = self.snapshot.account
        super().save(*args, **kwargs)
        self.snapshot.update_sum()

    def __str__(self):
        return f"{self.date} – {self.name}"

    def get_absolute_url(self):
        return reverse("transaction", kwargs={"pk": self.pk})

    def get_delete_url(self):
        return reverse("del_transaction", kwargs={"pk": self.pk})

    @property
    def invoices(self):
        return Invoice.objects.filter(transaction=self)

    @property
    def has_invoice(self):
        return self.invoices.count() > 0

    class Meta:
        ordering = ["-date"]
        verbose_name = _("Transaction")
        verbose_name_plural = _("Transactions")


def invoice_path(instance, filename):
    return pathlib.Path("invoices", str(instance.id)).with_suffix(".pdf")


class Invoice(CustomModel):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    name = models.CharField(
        max_length=256, default=_("Invoice"), verbose_name=_("Name")
    )
    file = models.FileField(
        upload_to=invoice_path,
        validators=[FileExtensionValidator(["pdf"])],
        verbose_name=_("File"),
        max_length=128,
    )
    transaction = models.ForeignKey(
        Transaction, on_delete=models.CASCADE, editable=False
    )

    def __str__(self):
        if hasattr(self, "transaction"):
            return f"{self.name} – {self.transaction.name}"
        return self.name

    def delete(self, *args, **kwargs):
        self.file.delete()
        super().delete(*args, **kwargs)

    def get_absolute_url(self):
        return reverse(
            "invoice", kwargs={"transaction_pk": self.transaction.pk, "pk": self.pk}
        )

    def get_delete_url(self):
        return reverse(
            "del_invoice", kwargs={"transaction_pk": self.transaction.pk, "pk": self.pk}
        )

    class Meta:
        verbose_name = _("Invoice")
        verbose_name_plural = _("Invoices")


class NummiForm(ModelForm):
    template_name = "main/form/base.html"

    def __init__(self, *args, **kwargs):
        kwargs.pop("user", None)
        super().__init__(*args, **kwargs)


class AccountForm(NummiForm):
    class Meta:
        model = Account
        fields = "__all__"


class CategoryForm(NummiForm):
    class Meta:
        model = Category
        fields = "__all__"


class TransactionForm(NummiForm):
    class Meta:
        model = Transaction
        fields = "__all__"

    def __init__(self, *args, **kwargs):
        _user = kwargs.pop("user")
        super().__init__(*args, **kwargs)
        self.fields["category"].queryset = Category.objects.filter(user=_user)
        self.fields["snapshot"].queryset = Snapshot.objects.filter(user=_user)


class InvoiceForm(NummiForm):
    prefix = "invoice"

    class Meta:
        model = Invoice
        fields = "__all__"


class SnapshotForm(NummiForm):
    class Meta:
        model = Snapshot
        fields = "__all__"

    def __init__(self, *args, **kwargs):
        _user = kwargs.pop("user")
        super().__init__(*args, **kwargs)
        self.fields["account"].queryset = Account.objects.filter(user=_user)