[trends] Fix concurrent reading trend

PROJECT.org

@@ -88,7 +88,7 @@ fetching and simple saving.
 *** Metadata sources
 **** Scraper
 
-* Backlog [1/21] :vrobbler:project:personal:
+* Backlog [2/22] :vrobbler:project:personal:
 ** TODO [#C] Create small utility to clean up tracks scrobbled with wonky playback times :bug:music:scrobbles:
 :PROPERTIES:
 :ID:       702462cf-d54b-48c6-8a7c-78b8de751deb
@@ -590,6 +590,10 @@ We should rename `email_scrobble_board_game` to reflect the fact that it's just
 a helper method to create board game scrobbles given a json blob. It's
 independent of the email flow it was originally creatdd for
 
+** DONE [#A] Concurrent reading trend does not consolidate on single book :trends:reading:
+:PROPERTIES:
+:ID:       fe220f55-7e0d-2a17-2477-a5aa7c4a1f2c
+:END:
 ** DONE [#B] Trends dont seem to look very far back :trends:
 :PROPERTIES:
 :ID:       ffcfba3f-5a93-9ee0-9680-666e6eccd684

vrobbler/apps/trends/trends/concurrent.py

@@ -216,43 +216,57 @@ def compute_concurrent_reading(user, period="all_time"):
     anchor_to_paired = _find_concurrent(anchor_scrobbles, paired_scrobbles)
     paired_by_pk = {s.pk: s for s in paired_scrobbles}
 
-    books = []
+    books_by_uuid = {}
 
     for anchor in anchor_scrobbles:
         paired_pks = anchor_to_paired.get(anchor.pk, [])
         if not paired_pks:
             continue
 
-        tracks_by_name = defaultdict(int)
-        track_details = {}
+        book = anchor.book
+        book_uuid = str(book.uuid) if book and book.uuid else ""
+        book_key = book_uuid or str(book) if book else "Unknown"
+
+        if book_key not in books_by_uuid:
+            books_by_uuid[book_key] = {
+                "book_title": str(book) if book else "Unknown",
+                "book_uuid": book_uuid,
+                "total_sessions": 0,
+                "tracks_by_name": defaultdict(int),
+                "track_details": {},
+            }
+
+        books_by_uuid[book_key]["total_sessions"] += len(paired_pks)
+
         for p_pk in paired_pks:
             ps = paired_by_pk[p_pk]
             track = ps.track
             if track is None:
                 continue
             name = str(track)
-            tracks_by_name[name] += 1
-            if name not in track_details:
-                track_details[name] = {
+            books_by_uuid[book_key]["tracks_by_name"][name] += 1
+            if name not in books_by_uuid[book_key]["track_details"]:
+                books_by_uuid[book_key]["track_details"][name] = {
                     "track_name": name,
                     "track_uuid": str(track.uuid) if track.uuid else "",
                     "artist_name": str(track.artist) if track.artist else "",
                 }
 
-        book = anchor.book
+    books = []
+    for bd in books_by_uuid.values():
         books.append(
             {
-                "book_title": str(book) if book else "Unknown",
-                "book_uuid": str(book.uuid) if book and book.uuid else "",
-                "total_sessions": len(paired_pks),
+                "book_title": bd["book_title"],
+                "book_uuid": bd["book_uuid"],
+                "total_sessions": bd["total_sessions"],
                 "tracks": sorted(
                     [
-                        {**track_details[name], "count": count}
-                        for name, count in tracks_by_name.items()
+                        {**bd["track_details"][name], "count": count}
+                        for name, count in bd["tracks_by_name"].items()
                     ],
                     key=lambda x: x["count"],
                     reverse=True,
-                )[:20],
+                )[:5],
             }
         )