init project tests

app/costs/models.py

@@ -3,36 +3,121 @@ from uuid import uuid4
 from django.db import models
 from django.conf import settings
 from django.utils.translation import gettext_lazy as _
+from django.core.validators import MinValueValidator, ValidationError
+from decimal import Decimal
 
-from bird.models import FallenBird
+from bird.models import Bird
+
+
+CHOICE_CATEGORY = [
+    ("medical", _("Medizinisch")),
+    ("food", _("Nahrung")),
+    ("equipment", _("Ausrüstung")),
+    ("transport", _("Transport")),
+    ("other", _("Sonstiges")),
+]
 
 
 class Costs(models.Model):
     id = models.UUIDField(primary_key=True, default=uuid4, editable=False)
+    
+    # Main relationship - could be to Bird or FallenBird
+    bird = models.ForeignKey(
+        Bird,
+        on_delete=models.SET_NULL,
+        blank=True,
+        null=True,
+        verbose_name=_("Vogel"),
+        related_name='costs'
+    )
     id_bird = models.ForeignKey(
-        FallenBird,
+        "bird.FallenBird",
         on_delete=models.SET_NULL,
         blank=True,
         null=True,
         verbose_name=_("Patient"),
+        related_name='costs'
     )
+    
+    # Cost details
+    description = models.CharField(
+        max_length=512,
+        default="",
+        verbose_name=_("Beschreibung")
+    )
+    amount = models.DecimalField(
+        max_digits=10,
+        decimal_places=2,
+        validators=[MinValueValidator(Decimal('0.00'))],
+        default=Decimal('0.00'),
+        verbose_name=_("Betrag")
+    )
+    cost_date = models.DateField(
+        null=True,
+        blank=True,
+        verbose_name=_("Kostendatum")
+    )
+    category = models.CharField(
+        max_length=20,
+        choices=CHOICE_CATEGORY,
+        default="other",
+        verbose_name=_("Kategorie")
+    )
+    
+    # Additional fields expected by tests
+    invoice_number = models.CharField(
+        max_length=100,
+        blank=True,
+        null=True,
+        verbose_name=_("Rechnungsnummer")
+    )
+    vendor = models.CharField(
+        max_length=256,
+        blank=True,
+        null=True,
+        verbose_name=_("Anbieter")
+    )
+    notes = models.TextField(
+        blank=True,
+        null=True,
+        verbose_name=_("Notizen")
+    )
+    
+    # Legacy field for backwards compatibility
     costs = models.DecimalField(
         max_digits=5,
         decimal_places=2,
         default="0.00",
-        verbose_name=_("Betrag"))
+        verbose_name=_("Betrag (legacy)"))
     created = models.DateField(
+        auto_now_add=True,
         verbose_name=_("Gebucht am"))
     comment = models.CharField(
         max_length=512,
         blank=True,
         null=True,
         verbose_name=_("Bemerkungen"))
+    
     user = models.ForeignKey(
         settings.AUTH_USER_MODEL,
         on_delete=models.CASCADE,
         verbose_name=_("Benutzer"))
+    created_by = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='costs_created',
+        null=True,
+        blank=True,
+        verbose_name=_("Erstellt von"))
 
     class Meta:
         verbose_name = _("Kosten")
         verbose_name_plural = _("Kosten")
+        
+    def clean(self):
+        """Validate that amount is not negative."""
+        if self.amount and self.amount < 0:
+            raise ValidationError(_("Betrag kann nicht negativ sein."))
+
+    def __str__(self):
+        return f"{self.description} - €{self.amount}"