move reschedCards() to backend

proto/backend.proto

@@ -105,6 +105,7 @@ service BackendService {
     rpc BuryOrSuspendCards (BuryOrSuspendCardsIn) returns (Empty);
     rpc EmptyFilteredDeck (DeckID) returns (Empty);
     rpc RebuildFilteredDeck (DeckID) returns (UInt32);
+    rpc ScheduleCardsAsReviews (ScheduleCardsAsReviewsIn) returns (Empty);
 
     // stats
 
@@ -1056,3 +1057,9 @@ message BuryOrSuspendCardsIn {
     repeated int64 card_ids = 1;
     Mode mode = 2;
 }
+
+message ScheduleCardsAsReviewsIn {
+    repeated int64 card_ids = 1;
+    uint32 min_interval = 2;
+    uint32 max_interval = 3;
+}

pylib/anki/schedv2.py

@@ -1419,29 +1419,9 @@ and (queue={QUEUE_TYPE_NEW} or (queue={QUEUE_TYPE_REV} and due<=?))""",
 
     def reschedCards(self, ids: List[int], imin: int, imax: int) -> None:
         "Put cards in review queue with a new interval in days (min, max)."
-        d = []
-        t = self.today
-        mod = intTime()
-        for id in ids:
-            r = random.randint(imin, imax)
-            d.append(
-                (
-                    max(1, r),
-                    r + t,
-                    self.col.usn(),
-                    mod,
-                    STARTING_FACTOR,
-                    id,
+        self.col.backend.schedule_cards_as_reviews(
+            card_ids=ids, min_interval=imin, max_interval=imax
         )
-            )
-        self.remFromDyn(ids)
-        self.col.db.executemany(
-            f"""
-update cards set type={CARD_TYPE_REV},queue={QUEUE_TYPE_REV},ivl=?,due=?,odue=0,
-usn=?,mod=?,factor=? where id=?""",
-            d,
-        )
-        self.col.log(ids)
 
     def resetCards(self, ids: List[int]) -> None:
         "Completely reset cards for export."

rslib/src/backend/mod.rs

@@ -547,6 +547,18 @@ impl BackendService for Backend {
         self.with_col(|col| col.rebuild_filtered_deck(input.did.into()).map(Into::into))
     }
 
+    fn schedule_cards_as_reviews(
+        &mut self,
+        input: pb::ScheduleCardsAsReviewsIn,
+    ) -> BackendResult<Empty> {
+        let cids: Vec<_> = input.card_ids.into_iter().map(CardID).collect();
+        let (min, max) = (input.min_interval, input.max_interval);
+        self.with_col(|col| {
+            col.reschedule_cards_as_reviews(&cids, min, max)
+                .map(Into::into)
+        })
+    }
+
     // statistics
     //-----------------------------------------------
 

rslib/src/card.rs

@@ -137,7 +137,18 @@ impl Card {
         }
     }
 
-    pub(crate) fn remove_from_filtered_deck(&mut self, sched: SchedulerVersion) {
+    /// Restores to the original deck and clears original_due.
+    /// This does not update the queue or type, so should only be used as
+    /// part of an operation that adjusts those separately.
+    pub(crate) fn remove_from_filtered_deck_before_reschedule(&mut self) {
+        if self.original_deck_id.0 != 0 {
+            self.deck_id = self.original_deck_id;
+            self.original_deck_id.0 = 0;
+            self.original_due = 0;
+        }
+    }
+
+    pub(crate) fn remove_from_filtered_deck_restoring_queue(&mut self, sched: SchedulerVersion) {
         if self.original_deck_id.0 == 0 {
             // not in a filtered deck
             return;

rslib/src/decks/filtered.rs

@@ -66,7 +66,7 @@ impl Collection {
         for cid in cids {
             if let Some(mut card) = self.storage.get_card(*cid)? {
                 let original = card.clone();
-                card.remove_from_filtered_deck(sched);
+                card.remove_from_filtered_deck_restoring_queue(sched);
                 self.update_card(&mut card, &original, usn)?;
             }
         }

rslib/src/sched/bury_and_suspend.rs

@@ -126,7 +126,7 @@ impl Collection {
             };
             if card.queue != desired_queue {
                 if sched == SchedulerVersion::V1 {
-                    card.remove_from_filtered_deck(sched);
+                    card.remove_from_filtered_deck_restoring_queue(sched);
                     card.remove_from_learning();
                 }
                 card.queue = desired_queue;

rslib/src/sched/mod.rs

@@ -8,6 +8,7 @@ use crate::{
 pub mod bury_and_suspend;
 pub(crate) mod congrats;
 pub mod cutoff;
+mod reviews;
 pub mod timespan;
 
 use chrono::FixedOffset;

rslib/src/sched/reviews.rs

@@ -0,0 +1,50 @@
+// Copyright: Ankitects Pty Ltd and contributors
+// License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+
+use crate::{
+    card::{Card, CardID, CardQueue, CardType},
+    collection::Collection,
+    deckconf::INITIAL_EASE_FACTOR,
+    err::Result,
+};
+use rand::distributions::{Distribution, Uniform};
+
+impl Card {
+    fn schedule_as_review(&mut self, interval: u32, today: u32) {
+        self.remove_from_filtered_deck_before_reschedule();
+        self.interval = interval.max(1);
+        self.due = (today + interval) as i32;
+        self.ctype = CardType::Review;
+        self.queue = CardQueue::Review;
+        if self.ease_factor == 0 {
+            // unlike the old Python code, we leave the ease factor alone
+            // if it's already set
+            self.ease_factor = INITIAL_EASE_FACTOR;
+        }
+    }
+}
+
+impl Collection {
+    pub fn reschedule_cards_as_reviews(
+        &mut self,
+        cids: &[CardID],
+        min_days: u32,
+        max_days: u32,
+    ) -> Result<()> {
+        let usn = self.usn()?;
+        let today = self.timing_today()?.days_elapsed;
+        let mut rng = rand::thread_rng();
+        let distribution = Uniform::from(min_days..=max_days);
+        self.transact(None, |col| {
+            col.set_search_table_to_card_ids(cids)?;
+            for mut card in col.storage.all_searched_cards()? {
+                let original = card.clone();
+                let interval = distribution.sample(&mut rng);
+                card.schedule_as_review(interval, today);
+                col.update_card(&mut card, &original, usn)?;
+            }
+            col.clear_searched_cards()?;
+            Ok(())
+        })
+    }
+}