From b73f3b5bb80f1c7b4792f7ebcdee2687a8655868 Mon Sep 17 00:00:00 2001
From: Josh Washburne <recursive.green@gmail.com>
Date: Sat, 11 Apr 2020 18:43:05 -0400
Subject: [PATCH] Ability to disable/enable replay variance.

---
 .../core/dynamic_preferences_registry.py      |  9 +++++++
 savepointradio/radio/models.py                | 26 +++++++++++--------
 2 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/savepointradio/core/dynamic_preferences_registry.py b/savepointradio/core/dynamic_preferences_registry.py
index 8577209..f329abf 100644
--- a/savepointradio/core/dynamic_preferences_registry.py
+++ b/savepointradio/core/dynamic_preferences_registry.py
@@ -96,6 +96,15 @@ class ReplayRatio(FloatPreference):
             raise ValidationError('Must be between 0.0 and 1.0, inclusive.')
 
 
+@global_preferences_registry.register
+class VarianceEnabled(BooleanPreference):
+    section = replay
+    name = 'variance_enabled'
+    help_text = 'Enable variance to replay time based on user ratings.'
+    default = False
+    required = False
+
+
 @global_preferences_registry.register
 class MinRatingsForVariance(IntegerPreference):
     section = replay
diff --git a/savepointradio/radio/models.py b/savepointradio/radio/models.py
index 63d7f9b..267963a 100644
--- a/savepointradio/radio/models.py
+++ b/savepointradio/radio/models.py
@@ -246,6 +246,20 @@ class Song(Disableable, Publishable, Timestampable, models.Model):
         return None
     average_rating = property(_average_rating)
 
+    def get_adjusted_ratio(self):
+        '''
+        Return a change to the replay ratio based on various factors.
+        '''
+        if radio_settings['replay__variance_enabled']:
+            min_ratings = radio_settings['replay__min_ratings_for_variance']
+            if self.rating_set.count() >= min_ratings:
+                ratio = radio_settings['replay__rating_variance_ratio']
+
+                # -((average - 1)/(highest_rating - 1)) * ratio
+                base = -((self._average_rating() - 1) / 4) * ratio
+                return float(base + (ratio * 0.5))
+        return float(0.0)
+
     def get_time_until_requestable(self):
         '''
         Length of time before a song can be requested again.
@@ -267,17 +281,7 @@ class Song(Disableable, Publishable, Timestampable, models.Model):
 
         if self._is_song() and self._is_available():
             if last:
-                # Check if we have enough ratings to change ratio
-                min_rate = radio_settings['replay__min_ratings_for_variance']
-                if self.rating_set.count() >= min_rate:
-                    ratio = radio_settings['replay__rating_variance_ratio']
-
-                    # -((average - 1)/(highest_rating - 1)) * ratio
-                    base = -((self._average_rating() - 1) / 4) * ratio
-                    adjusted_ratio = float(base + (ratio * 0.5))
-                else:
-                    adjusted_ratio = float(0.0)
-
+                adjusted_ratio = self.get_adjusted_ratio()
                 return last + Song.music.wait_total(adjusted_ratio)
             return timezone.now()
         return None