refactor: move logic for finding the fallback show

program/services.py

@@ -700,6 +700,17 @@ def generate_conflicts(timeslots: list[TimeSlot]) -> Conflicts:
     return conflicts
 
 
+def get_fallback_show(raise_exceptions: bool = False):
+    radio_settings: RadioSettings | None = RadioSettings.objects.first()
+    fallback_show = radio_settings.fallback_show if radio_settings is not None else None
+    if raise_exceptions and fallback_show is None:
+        raise ConfigurationError(
+            "Radio settings must define a fallback show if include_virtual is True.",
+            code="no-fallback-show-defined",
+        )
+    return fallback_show
+
+
 def generate_program_entries(
     queryset: QuerySet[TimeSlot],
     *,
@@ -743,13 +754,9 @@ def generate_program_entries(
         yield from (create_timeslot_entry(timeslot) for timeslot in queryset)
         return
 
-    radio_settings: RadioSettings | None = RadioSettings.objects.first()
-    fallback_show = radio_settings.fallback_show if radio_settings is not None else None
-    if fallback_show is None:
-        raise ConfigurationError(
-            "Radio settings must define a fallback show if include_virtual is True.",
-            code="no-fallback-show-defined",
-        )
+    # Program entries that are not based on scheduled timeslots are generated using the fallback
+    # show. We can only create these program entries if a fallback show has been specified.
+    fallback_show = get_fallback_show(raise_exceptions=True)
 
     entry_start = start
     timeslot: TimeSlot