Rework display of available cards in custom study

In v3, it's more informative to show the count of child decks separately,
since increasing the limit of the current deck does not increase the limits
of child decks. When we rework the decks list in the future, a tooltip
will hopefully provide an easier way for users to see where cards are
available, and where limits are being applied.

Closes #1868

ftl/core/custom-study.ftl

@@ -24,8 +24,11 @@ custom-study-select = Select
 custom-study-select-tags-to-exclude = Select tags to exclude:
 custom-study-selective-study = Selective Study
 custom-study-study-by-card-state-or-tag = Study by card state or tag
-custom-study-available-new-cards = Available new cards: { $count }
-custom-study-available-review-cards = Available review cards: { $count }
+custom-study-available-new-cards-2 = Available new cards: { $countString }
+custom-study-available-review-cards-2 = Available review cards: { $countString }
+custom-study-available-child-count = ({ $count } in subdecks)
 
 ## DEPRECATED - you do not need to translate these.
 
+custom-study-available-new-cards = Available new cards: { $count }
+custom-study-available-review-cards = Available review cards: { $count }

proto/anki/scheduler.proto

@@ -291,4 +291,7 @@ message CustomStudyDefaultsResponse {
   uint32 extend_review = 3;
   uint32 available_new = 4;
   uint32 available_review = 5;
+  // in v3, counts for children are provided separately
+  uint32 available_new_in_children = 6;
+  uint32 available_review_in_children = 7;
 }

qt/aqt/customstudy.py

@@ -1,6 +1,8 @@
 # Copyright: Ankitects Pty Ltd and contributors
 # License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
+from __future__ import annotations
+
 from typing import Tuple
 
 import aqt
@@ -75,6 +77,12 @@ class CustomStudy(QDialog):
         qconnect(f.radioPreview.clicked, lambda: self.onRadioChange(RADIO_PREVIEW))
         qconnect(f.radioCram.clicked, lambda: self.onRadioChange(RADIO_CRAM))
 
+    def count_with_children(self, parent: int, children: int) -> str:
+        if children:
+            return f"{parent} {tr.custom_study_available_child_count(children)}"
+        else:
+            return str(parent)
+
     def onRadioChange(self, idx: int) -> None:
         form = self.form
         min_spinner_value = 1
@@ -86,15 +94,21 @@ class CustomStudy(QDialog):
         ok = tr.custom_study_ok()
 
         if idx == RADIO_NEW:
-            title_text = tr.custom_study_available_new_cards(
-                count=self.defaults.available_new
+            title_text = tr.custom_study_available_new_cards_2(
+                count_string=self.count_with_children(
+                    self.defaults.available_new,
+                    self.defaults.available_new_in_children,
+                ),
             )
             text_before_spinner = tr.custom_study_increase_todays_new_card_limit_by()
             current_spinner_value = self.defaults.extend_new
             min_spinner_value = -DYN_MAX_SIZE
         elif idx == RADIO_REV:
-            title_text = tr.custom_study_available_review_cards(
-                count=self.defaults.available_review
+            title_text = tr.custom_study_available_review_cards_2(
+                count_string=self.count_with_children(
+                    self.defaults.available_review,
+                    self.defaults.available_review_in_children,
+                ),
             )
             text_before_spinner = tr.custom_study_increase_todays_review_limit_by()
             current_spinner_value = self.defaults.extend_review

qt/aqt/main.py

@@ -1,5 +1,6 @@
 # Copyright: Ankitects Pty Ltd and contributors
 # License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+
 from __future__ import annotations
 
 import enum

rslib/src/scheduler/filtered/custom_study.rs

@@ -34,8 +34,29 @@ impl Collection {
             .deck_tree(Some(TimestampSecs::now()))?
             .get_deck(deck_id)
             .ok_or(AnkiError::NotFound)?;
-        let available_new = subtree.sum(|node| node.new_uncapped);
-        let available_review = subtree.sum(|node| node.review_uncapped);
+        let v3 = self.get_config_bool(BoolKey::Sched2021);
+        let available_new_including_children = subtree.sum(|node| node.new_uncapped);
+        let available_review_including_children = subtree.sum(|node| node.review_uncapped);
+        let (
+            available_new,
+            available_new_in_children,
+            available_review,
+            available_review_in_children,
+        ) = if v3 {
+            (
+                subtree.new_uncapped,
+                available_new_including_children - subtree.new_uncapped,
+                subtree.review_uncapped,
+                available_review_including_children - subtree.review_uncapped,
+            )
+        } else {
+            (
+                available_new_including_children,
+                0,
+                available_review_including_children,
+                0,
+            )
+        };
         // tags
         let include_tags: HashSet<String> = self.get_config_default(
             DeckConfigKey::CustomStudyIncludeTags
@@ -67,6 +88,8 @@ impl Collection {
             extend_review,
             available_new,
             available_review,
+            available_new_in_children,
+            available_review_in_children,
         })
     }
 }