implemented issue 1 - vanila version that works without user event data for playlist, clip position, clip index. To be updated as the data is updated

recommendation_engine.py

@@ -15,6 +15,7 @@ import ox
 from utils import run_async
 
 logger = logging.getLogger(__name__)
+verbose = True
 
 
 class Engine:
@@ -83,24 +84,94 @@ class Engine:
                     clips[inpoint['index']]['out'] = self.pandora.get(video_id, ['duration'])['duration']
         return clips
 
-### TASK 1 ###
-# Change this to (1) check if there's no grid event and if so: initialize, and 
-# (2) if not: add serendipity to the current grid mix using gridChange variables. 
-
     def get_videos(self, user):
+        channels = {k: v.get('value', 0) for k, v in self.state['channels'].items()}
+        sliders = {k: v.get('value', 0) for k, v in self.state['globalKeywords'].items()}
+        grid_change = {k: v.get('value', 0) for k, v in self.state['gridChange'].items()}
+
+        # check if there were grid events for all indexes.
+        grid_events = {}
+        (nc, np, ns) = (grid_change.get("nextClip"), grid_change.get("nextPlaylist"), grid_change.get("staySame"))
+        # this assumes np + nc + ns = total number of videos in the grid view (16). 
+        # Make sure sanity check exists in front-end (error if it does not add up to 16).
+        video_num = nc + np + ns 
+
+        for event in user.get('events', []):
+            if event.get('event') == "grid" and event.get('data').get('index') not in grid_events:
+                grid_events[event.get('data').get('index')] = event.get('data')
+            if len(grid_events) == video_num:
+                break
+        prev_grid_list = sorted([v for v in grid_events.values()], key=lambda k:k['index'])
+
+        # if there were no grid events for all, initialize all grids.
+        if len(prev_grid_list) < video_num: 
+            return self.get_recommendations(user)
+
+        else:
+            # Once the "index" is added to play event data, played index will be excluded from the random shuffle 
+            # and deterministically added to staySame pool.
+            # video_indx = [*range(playIndex)]+[*range(playIndex+1,video_num)]
+            video_indx = list(range(video_num))
+            random.shuffle(video_indx)
+            rec_list = []
+            # For now, randomly choose a clip in the same playlist instead of switching to the next clip. 
+            # This will be changed once the clip position is tracked in the user data.
+            for i in video_indx[:nc]:
+                if prev_grid_list[i].get('playlist') is None:
+                # add this to deal with the absence of "playlist" data in a grid event temporarily.
+                # If there's no playlist data recorded, add the nextClip pool to nextPlaylist pool for now.
+                    np += nc
+                    nc = 0
+                    break
+                else:
+                # if "playlist" data exists in grid event (it should be in the future)
+                    for playlist in playlists:    
+                        if playlist.get('name')== prev_grid_list[i].get('playlist'):
+                            rec_list.append((i, {
+                                'clips': playlist['clips'],
+                                'position': random.randrange(len(playlist['clips'])),
+                                'name': playlist['name'],
+                                'tags': playlist['tags'],
+                            }))
+
+            # randomly select playlists (excluding the playlists from the current grid once "playlist" is recorded for grid events)
+            # for nextPlaylist pool
+            vids_exclude = []
+            # vids_exclude = [e.get("playlist") for e in prev_grid_list]
+            video = self.get_recommendations(user, vids_exclude)
+            rec_list += [(i, video[i]) for i in video_indx[nc:nc+np]]
+
+            #staySame pool
+            rec_list += [(i,{}) for i in video_indx[nc+np:]]
+
+            rec_list = sorted(rec_list, key=lambda k:k[0])
+            return [e[1] for e in rec_list]
+
+
+# NOTE for future improvement: vids_exclude element unit could be clip or in/out time pairs, rather than playlist. 
+# The same playlist could be played in the grid view as long as these are differenct clips or separate times.
+    def get_recommendations(self, user, vids_exclude = []):
         channels = {k: v.get('value', 0) for k, v in self.state['channels'].items()}
         sliders = {k: v.get('value', 0) for k, v in self.state['globalKeywords'].items()}
         gridChange = {k: v.get('value', 0) for k, v in self.state['gridChange'].items()}
+
+        # Exclude playlists from the most recent grid 
+        playlists = self.playlists
+        if len(vids_exclude) > 0:
+            for playlist in playlists:
+                if playlist["name"] in vids_exclude:
+                    playlists.remove(playlist)
+
         # For each playlist, compute user keyword score
         user_keywords = user.get('keywords', {})
         score = {}
-        for playlist in self.playlists:
+        for playlist in playlists:
             score[playlist['name']] = random.random()
             for tag in [tag for tag in playlist['tags'] if tag in user_keywords]:
                 score[playlist['name']] += user_keywords[tag]
         # Select highest scoring playlists
         playlists = sorted(
-            self.playlists,
+            playlists,
             key=lambda playlist: -score[playlist['name']]
         )
         videos = playlists[:channels['userKeywords']]
@@ -143,11 +214,18 @@ class Engine:
         } for video in videos]
 
 
-### TASK 2 ### 
-# Change this to make sure the next playlist is not the current playlist 
-# AND not the playlists displayed in the current grid. Incorporate the change from Task 1.
     def get_next(self, user, position):
-        video = self.get_videos(user)[position]
+        grid_events = {}
+        video_num = 16 
+
+        for event in user.get('events', []):
+            if event.get('event') == "grid" and event.get('data').get('index') not in grid_events:
+                grid_events[event.get('data').get('index')] = event.get('data')
+            if len(grid_events) == video_num:
+                break
+        prev_grid_list = sorted([v for v in grid_events.values()], key=lambda k:k['index'])
+        vids_exclude = [e.get("playlist") for e in prev_grid_list]
+        video = self.get_recommendations(user, vids_exclude)[position]
         return video
 
     def update_state(self, data):