Add parent albums

gallery/models/album.py

@@ -1,5 +1,6 @@
 from datetime import datetime
 
+from django.core.exceptions import ValidationError
 from django.db import models
 from django.templatetags.static import static
 from django.urls import reverse
@@ -7,12 +8,11 @@ from django.utils.text import slugify
 
 from gallery.models.location import Location
 
-#from gallery.models.photo import Photo
-
 
 class Album(models.Model):
     name = models.CharField(max_length=150, unique=True, verbose_name="Album")
     slug = models.SlugField(max_length=150, unique=True, verbose_name="Slug")
+    parent = models.ForeignKey('self', on_delete=models.SET_NULL, blank=True, null=True, limit_choices_to={'parent__isnull': True}, related_name='children', verbose_name="Parent Album")
     location = models.ForeignKey(Location, blank=True, null=True, on_delete=models.SET_NULL, related_name='albums', verbose_name="Location")
     album_date = models.DateField(default=datetime.now, verbose_name="Album Date")
     cover = models.ForeignKey("Photo", blank=True, null=True, on_delete=models.SET_NULL, related_name='cover_to', verbose_name="Album cover")
@@ -30,6 +30,11 @@ class Album(models.Model):
         if random_cover:
             return random_cover.photo.url
         return static('img/placeholder.png')
+    
+    def clean(self):
+        super().clean()
+        if self.parent and self.parent == self:
+            raise ValidationError({'parent': "An album cannot be its own parent."})
 
     def save(self, *args, **kwargs):
         if not self.slug:
@@ -41,6 +46,7 @@ class Album(models.Model):
 
     class Meta:
         verbose_name_plural = "Albums"
+        ordering = ('album_date',)
 
     def __str__(self):
         return '{}'.format(self.name)