[scrobbles] Add total time to tag views

vrobbler/apps/scrobbles/views.py

@@ -14,7 +14,7 @@ from django.contrib import messages
 from django.contrib.auth import get_user_model
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.core.paginator import EmptyPage, PageNotAnInteger, Paginator
-from django.db.models import Count, Max, Q
+from django.db.models import Count, Max, Q, Sum
 from django.db.models.query import QuerySet
 from rest_framework.authentication import TokenAuthentication
 from rest_framework.authtoken.models import Token
@@ -367,6 +367,7 @@ class ScrobbleListView(LoginRequiredMixin, ListView):
         else:
             tag_list = []
         self.tag_list = tag_list
+        self._full_queryset = qs
         return qs
 
     def _compute_overlap_groups(self, scrobbles):
@@ -433,6 +434,13 @@ class ScrobbleListView(LoginRequiredMixin, ListView):
         ctx["tag_list"] = getattr(self, "tag_list", [])
         scrobbles = list(ctx.get("object_list", []))
         ctx["overlap_map"] = self._compute_overlap_groups(scrobbles)
+        full_qs = getattr(self, "_full_queryset", None)
+        if full_qs is not None and getattr(self, "tag_list", []):
+            total = (
+                full_qs.aggregate(total=Sum("playback_position_seconds"))["total"]
+                or 0
+            )
+            ctx["total_time_seconds"] = total
         return ctx