keep is_free up to date

core/bookloader.py

@@ -474,6 +474,8 @@ def merge_works(w1, w2, user=None):
         w1.description = w2.description
     if w2.featured and not w1.featured:
         w1.featured = w2.featured
+    if w2.is_free and not w1.is_free:
+        w1.is_free = True
     w1.save()
     for wishlist in models.Wishlist.objects.filter(works__in=[w2]):
         w2source = wishlist.work_source(w2)

core/models.py

@@ -26,7 +26,7 @@ from django.core.urlresolvers import reverse
 from django.core.files.base import ContentFile
 from django.db import models
 from django.db.models import F, Q, get_model
-from django.db.models.signals import post_save
+from django.db.models.signals import post_save, pre_delete
 from django.utils.translation import ugettext_lazy as _
 
 '''
@@ -1862,6 +1862,21 @@ class Ebook(models.Model):
         self.active=True
         self.save()
 
+def set_free_flag(sender, instance, created,  **kwargs):
+    if created:
+        if not instance.edition.work.is_free:
+            instance.edition.work.is_free = True
+            instance.edition.work.save()
+
+post_save.connect(set_free_flag,sender=Ebook)
+
+def reset_free_flag(sender, instance, **kwargs):
+    if instance.edition.work.ebooks().count()==1:
+        instance.edition.work.is_free = False
+        instance.edition.work.save()
+
+pre_delete.connect(reset_free_flag,sender=Ebook)
+
 class Wishlist(models.Model):
     created = models.DateTimeField(auto_now_add=True)
     user = models.OneToOneField(User, related_name='wishlist')

core/tests.py

@@ -183,6 +183,9 @@ class BookLoaderTests(TestCase):
         e2 = Edition(work=w2)
         e2.save()
         
+        eb1 = Ebook(edition = e2)
+        eb1.save()
+        
         e2a = Edition(work=w2)
         e2a.save()
         
@@ -192,7 +195,10 @@ class BookLoaderTests(TestCase):
         self.assertTrue(e1.work)
         self.assertTrue(e2.work)
         self.assertEqual(models.Work.objects.count(), 2)
- 
+        
+        self.assertTrue(w2.is_free)
+        self.assertFalse(w1.is_free)
+        
         w1_id = w1.id
         w2_id = w2.id
         
@@ -206,6 +212,8 @@ class BookLoaderTests(TestCase):
         self.assertEqual(models.WasWork.objects.count(),1)
         self.assertEqual(w1.subjects.count(),2)
        
+        self.assertTrue(w1.is_free)
+
         # getting proper view?
         anon_client = Client()
         r = anon_client.get("/work/%s/" % w1_id)
@@ -788,6 +796,11 @@ class DownloadPageTest(TestCase):
         response = anon_client.get("/work/%s/download/" % w.id, follow=True)
         self.assertContains(response, "/download_ebook/%s/"% eb1.id, count=10) 
         self.assertContains(response, "/download_ebook/%s/"% eb2.id, count=5)
+        self.assertTrue(eb1.edition.work.is_free)
+        eb1.delete()
+        self.assertTrue(eb2.edition.work.is_free)
+        eb2.delete()
+        self.assertFalse(eb2.edition.work.is_free)
 
 
 class LocaldatetimeTest(TestCase):