From dc8a687b3317e657c87dc4357f582a89c4a064f3 Mon Sep 17 00:00:00 2001
From: Luc Mcgrady <lucmcgrady@gmail.com>
Date: Sun, 13 Jul 2025 09:53:03 +0100
Subject: [PATCH] backend part

---
 proto/anki/scheduler.proto            |  6 ++++++
 rslib/src/scheduler/fsrs/simulator.rs | 26 ++++++++++++++++++++++++++
 rslib/src/scheduler/service/mod.rs    |  8 ++++++++
 3 files changed, 40 insertions(+)

diff --git a/proto/anki/scheduler.proto b/proto/anki/scheduler.proto
index 1294b4543..56ad389ee 100644
--- a/proto/anki/scheduler.proto
+++ b/proto/anki/scheduler.proto
@@ -55,6 +55,8 @@ service SchedulerService {
       returns (ComputeOptimalRetentionResponse);
   rpc SimulateFsrsReview(SimulateFsrsReviewRequest)
       returns (SimulateFsrsReviewResponse);
+  rpc SimulateFsrsWorkload(SimulateFsrsReviewRequest)
+      returns (SimulateFsrsWorkloadResponse);
   rpc EvaluateParams(EvaluateParamsRequest) returns (EvaluateParamsResponse);
   rpc EvaluateParamsLegacy(EvaluateParamsLegacyRequest)
       returns (EvaluateParamsResponse);
@@ -414,6 +416,10 @@ message SimulateFsrsReviewResponse {
   repeated float daily_time_cost = 4;
 }
 
+message SimulateFsrsWorkloadResponse {
+  map<uint32, float> dr_workload = 1;
+}
+
 message ComputeOptimalRetentionResponse {
   float optimal_retention = 1;
 }
diff --git a/rslib/src/scheduler/fsrs/simulator.rs b/rslib/src/scheduler/fsrs/simulator.rs
index e032ecaf3..99ca42989 100644
--- a/rslib/src/scheduler/fsrs/simulator.rs
+++ b/rslib/src/scheduler/fsrs/simulator.rs
@@ -1,3 +1,4 @@
+use std::collections::HashMap;
 // Copyright: Ankitects Pty Ltd and contributors
 // License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 use std::sync::Arc;
@@ -6,6 +7,7 @@ use anki_proto::deck_config::deck_config::config::ReviewCardOrder;
 use anki_proto::deck_config::deck_config::config::ReviewCardOrder::*;
 use anki_proto::scheduler::SimulateFsrsReviewRequest;
 use anki_proto::scheduler::SimulateFsrsReviewResponse;
+use anki_proto::scheduler::SimulateFsrsWorkloadResponse;
 use fsrs::simulate;
 use fsrs::PostSchedulingFn;
 use fsrs::ReviewPriorityFn;
@@ -267,6 +269,30 @@ impl Collection {
             daily_time_cost: result.cost_per_day,
         })
     }
+
+    pub fn simulate_workload(
+        &mut self,
+        req: SimulateFsrsReviewRequest,
+    ) -> Result<SimulateFsrsWorkloadResponse> {
+        let (config, cards) = self.simulate_request_to_config(&req)?;
+        let dr_workload = (70u32..=99u32)
+            .map(|dr| {
+                let result = simulate(
+                    &config,
+                    &req.params,
+                    dr as f32 / 100.,
+                    None,
+                    Some(cards.clone()),
+                )?;
+                Ok((
+                    dr,
+                    result.memorized_cnt_per_day.last().unwrap_or(&0.)
+                        / result.cost_per_day.iter().sum::<f32>(),
+                ))
+            })
+            .collect::<Result<HashMap<_, _>>>()?;
+        Ok(SimulateFsrsWorkloadResponse { dr_workload })
+    }
 }
 
 impl Card {
diff --git a/rslib/src/scheduler/service/mod.rs b/rslib/src/scheduler/service/mod.rs
index 43d694e4f..9f42a79f7 100644
--- a/rslib/src/scheduler/service/mod.rs
+++ b/rslib/src/scheduler/service/mod.rs
@@ -16,6 +16,7 @@ use anki_proto::scheduler::FuzzDeltaResponse;
 use anki_proto::scheduler::GetOptimalRetentionParametersResponse;
 use anki_proto::scheduler::SimulateFsrsReviewRequest;
 use anki_proto::scheduler::SimulateFsrsReviewResponse;
+use anki_proto::scheduler::SimulateFsrsWorkloadResponse;
 use fsrs::ComputeParametersInput;
 use fsrs::FSRSItem;
 use fsrs::FSRSReview;
@@ -283,6 +284,13 @@ impl crate::services::SchedulerService for Collection {
         self.simulate_review(input)
     }
 
+    fn simulate_fsrs_workload(
+        &mut self,
+        input: SimulateFsrsReviewRequest,
+    ) -> Result<SimulateFsrsWorkloadResponse> {
+        self.simulate_workload(input)
+    }
+
     fn compute_optimal_retention(
         &mut self,
         input: SimulateFsrsReviewRequest,