Feat/flatten

__init__.py

@@ -9,6 +9,7 @@
 from .schedule.reschedule import reschedule
 from .schedule.postpone import postpone
 from .schedule.advance import advance
+from .schedule.flatten import flatten
 from .schedule.reset import clear_custom_data
 from .schedule.disperse_siblings import disperse_siblings
 from .schedule.easy_days import (
@@ -143,6 +144,9 @@ def reschedule_recent(did):
 menu_advance = build_action(advance, "Advance cards in all decks")
 add_action_to_gear(advance, "Advance cards")
 
+menu_flatten = build_action(flatten, "Flatten cards in all decks")
+add_action_to_gear(flatten, "Flatten cards")
+
 menu_reset = build_action(clear_custom_data, "Clear custom data in all cards")
 
 menu_disperse_siblings = build_action(disperse_siblings, "Disperse all siblings")
@@ -192,6 +196,7 @@ def sponsor(did=None):
 menu_for_helper.addAction(menu_reschedule_recent)
 menu_for_helper.addAction(menu_postpone)
 menu_for_helper.addAction(menu_advance)
+menu_for_helper.addAction(menu_flatten)
 menu_for_helper.addAction(menu_reset)
 menu_for_helper.addAction(menu_disperse_siblings)
 menu_for_helper.addSeparator()

schedule/flatten.py

@@ -0,0 +1,164 @@
+from collections import defaultdict
+from ..utils import *
+from anki.decks import DeckManager
+from anki.utils import ids2str
+
+
+def get_desired_flatten_limit_with_response(did):
+    inquire_text = "Enter the maximum number of reviews you want in the future.\n"
+    info_text = "This feature only affects the cards that have been scheduled by FSRS.\n"
+    warning_text = "This feature doesn't respect maximum interval settings.\n"
+    (s, r) = getText(inquire_text + info_text + warning_text, default="100")
+    if r:
+        return (RepresentsInt(s), r)
+    return (None, r)
+
+
+def flatten(did):
+    if not mw.col.get_config("fsrs"):
+        tooltip(FSRS_ENABLE_WARNING)
+        return
+
+    (desired_flatten_limit, resp) = get_desired_flatten_limit_with_response(did)
+    if desired_flatten_limit is None:
+        if resp:
+            showWarning("Please enter the number of cards you want to flatten.")
+        return
+    else:
+        if desired_flatten_limit <= 0:
+            showWarning("Please enter a positive integer.")
+            return
+
+    start_time = time.time()
+
+    def on_done(future):
+        finish_text = future.result()
+        mw.progress.finish()
+        tooltip(f"{finish_text} in {time.time() - start_time:.2f} seconds")
+        mw.reset()
+
+    fut = mw.taskman.run_in_background(
+        lambda: flatten_background(did, desired_flatten_limit), on_done
+    )
+    return fut
+
+
+def flatten_background(did, desired_flatten_limit):
+    DM = DeckManager(mw.col)
+    if did is not None:
+        did_list = ids2str(DM.deck_and_child_ids(did))
+
+    today = mw.col.sched.today
+    true_due = "CASE WHEN odid==0 THEN due ELSE odue END"
+
+    cards_exceed_future = mw.col.db.all(
+        f"""
+    WITH ranked_cards AS (
+        SELECT id,
+            true_due,
+            ivl,
+            ROW_NUMBER() OVER (
+                PARTITION BY true_due
+                ORDER BY ivl / cast({ today } - true_due + 0.001 as real)
+            ) AS rank
+        FROM (
+                SELECT id,
+                    {true_due} AS true_due,
+                    ivl
+                FROM cards
+                WHERE true_due >= { today }
+                AND queue = {QUEUE_TYPE_REV}
+                {"AND did IN %s" % did_list if did is not None else ""}
+            )
+    ),
+    overdue AS (
+        SELECT {true_due} AS true_due
+        FROM cards
+        WHERE true_due >= { today }
+        AND queue = {QUEUE_TYPE_REV}
+        {"AND did IN %s" % did_list if did is not None else ""}
+        GROUP BY true_due
+        HAVING COUNT(*) > { desired_flatten_limit }
+    )
+    SELECT id
+        , true_due
+        , ivl
+    FROM ranked_cards
+    WHERE true_due IN (
+            SELECT true_due
+            FROM overdue
+        )
+        AND rank > { desired_flatten_limit }
+    ORDER BY ivl / cast({ today } - true_due + 0.001 as real)
+        """
+    )
+    cards_backlog = mw.col.db.all(
+        f"""
+    SELECT id,
+        {true_due} AS true_due,
+        ivl
+    FROM cards
+    WHERE true_due < { today }
+    AND queue = {QUEUE_TYPE_REV}
+    {"AND did IN %s" % did_list if did is not None else ""}
+    ORDER BY ivl / cast({ today } - true_due + 0.001 as real)
+    """
+    )
+
+    cards_to_flatten = cards_exceed_future + cards_backlog
+
+    due_cnt_per_day = defaultdict(
+        int,
+        {
+            day: cnt
+            for day, cnt in mw.col.db.all(
+                f"""SELECT {true_due} AS true_due, count() 
+                        FROM cards 
+                        WHERE true_due >= { today }
+                        AND queue = {QUEUE_TYPE_REV}
+                        {"AND did IN %s" % did_list if did is not None else ""}
+                        GROUP BY {true_due}"""
+            )
+        },
+    )
+
+    undo_entry = mw.col.add_custom_undo_entry("flatten")
+    mw.progress.start()
+    cnt = 0
+    cancelled = False
+    total_cnt = len(cards_to_flatten)
+
+    for new_due in range(today, today + 36500):
+        if cancelled:
+            break
+        rest_cnt = len(cards_to_flatten) - cnt
+        if rest_cnt <= 0:
+            break
+        due_cnt = due_cnt_per_day[new_due]
+        if due_cnt > desired_flatten_limit:
+            continue
+        quota = desired_flatten_limit - due_cnt
+        start_index = cnt
+        end_index = cnt + min(quota, rest_cnt)
+        for cid, due, ivl in cards_to_flatten[start_index:end_index]:
+            card = mw.col.get_card(cid)
+            last_review = get_last_review_date(card)
+            new_ivl = new_due - last_review
+            card = update_card_due_ivl(card, new_ivl)
+            write_custom_data(card, "v", "flatten")
+            mw.col.update_card(card)
+            mw.col.merge_undo_entries(undo_entry)
+            cnt += 1
+            if cnt % 500 == 0:
+                mw.taskman.run_on_main(
+                    lambda: mw.progress.update(
+                        label=f"{cnt}/{total_cnt} cards flattened",
+                        value=cnt,
+                        max=total_cnt,
+                    )
+                )
+                if mw.progress.want_cancel():
+                    cancelled = True
+
+    finish_text = f"{cnt} cards flattened"
+    return finish_text