Implement Popularimeter beetbox#23

mediafile.py

@@ -1222,6 +1222,8 @@ def _none_value(self):
             return False
         elif self.out_type == six.text_type:
             return u''
+        elif self.out_type == dict:
+            return {}
 
 
 class ListMediaField(MediaField):
@@ -1414,6 +1416,34 @@ def __delete__(self, mediafile):
         delattr(mediafile, 'images')
 
 
+class PopmMediaField(MediaField):
+    """ Access Popularimeter as dictionary."""
+
+
+class MP3PopmStorageStyle(StorageStyle):
+    formats = ['MP3']
+
+    def get(self, mutagen_file):
+        """Returns POPM dictionary: {EMAIL: {'rating': RATING, 'count': COUNT}}
+        """
+        return {
+            popm.email: {'rating': popm.rating, 'count': popm.count}
+            for popm in mutagen_file.tags.getall('POPM')
+        }
+
+    def set(self, mutagen_file, value):
+        """Set POPM. 'count' will be set to 0 by default."""
+        popm_list = [
+            mutagen.id3.POPM(
+                email=email,
+                rating=value[email]['rating'],
+                count=value[email].get('count', 0)
+            )
+            for email in value.keys()
+        ]
+        mutagen_file.tags.setall('POPM', popm_list)
+
+
 class QNumberField(MediaField):
     """Access integer-represented Q number fields.
 
@@ -1849,6 +1879,10 @@ def update(self, dict):
         StorageStyle('MUSICBRAINZ_ALBUMCOMMENT'),
         ASFStorageStyle('MusicBrainz/Album Comment'),
     )
+    popm = PopmMediaField(
+        MP3PopmStorageStyle(key='POPM', as_type=list),
+        out_type=dict
+    )
 
     # Release date.
     date = DateField(

test/test_mediafile.py

@@ -755,6 +755,37 @@ def test_unknown_apic_type(self):
         mediafile = self._mediafile_fixture('image_unknown_type')
         self.assertEqual(mediafile.images[0].type, ImageType.other)
 
+    def test_write_single_popm(self):
+        mediafile = self._mediafile_fixture('empty')
+        test_email = '[email protected]'
+        mediafile.popm = {
+            test_email: {'rating': 1, 'count': 1}
+        }
+        mediafile.save()
+        self.assertEqual(mediafile.popm, {
+            test_email: {'rating': 1, 'count': 1}
+        })
+
+    def test_write_popm_without_count(self):
+        mediafile = self._mediafile_fixture('empty')
+        test_email = '[email protected]'
+        mediafile.popm = {test_email: {'rating': 1}}
+        mediafile.save()
+        self.assertEqual(mediafile.popm, {
+            test_email: {'rating': 1, 'count': 0}
+        })
+
+    def test_write_multiple_popm(self):
+        mediafile = self._mediafile_fixture('full')
+        mediafile.popm = {'[email protected]': {'rating': 1, 'count': 1},
+                          '[email protected]': {'rating': 2, 'count': 2}}
+        mediafile.save()
+
+        self.assertEqual(mediafile.popm, {
+            '[email protected]': {'rating': 1, 'count': 1},
+            '[email protected]': {'rating': 2, 'count': 2},
+        })
+
 
 class MP4Test(ReadWriteTestBase, PartialTestMixin,
               ImageStructureTestMixin, unittest.TestCase):
@@ -975,7 +1006,7 @@ def test_properties_from_readable_fields(self):
 
     def test_known_fields(self):
         fields = list(ReadWriteTestBase.tag_fields)
-        fields.extend(('encoder', 'images', 'genres', 'albumtype'))
+        fields.extend(('encoder', 'images', 'genres', 'albumtype', 'popm'))
         assertCountEqual(self, MediaFile.fields(), fields)
 
     def test_fields_in_readable_fields(self):