From dcf9a1f5d5349a743f57460fe77f92d9f4631699 Mon Sep 17 00:00:00 2001
From: czh <2565523901@qq.com>
Date: Mon, 9 Mar 2026 19:05:45 +0800
Subject: [PATCH] feat: add input validation for scheduler options

Add validation for critical scheduler parameters:

- desired_retention must be between 0.0 and 1.0 (exclusive)
- maximum_interval must be a positive integer (>= 1)
- Provide clear error messages with actual values received

This prevents misconfiguration and provides early feedback
on invalid scheduler settings.
---
 lib/lulucat/fsrs_scheduler.ex | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/lib/lulucat/fsrs_scheduler.ex b/lib/lulucat/fsrs_scheduler.ex
index 2410a3d..bd034e8 100644
--- a/lib/lulucat/fsrs_scheduler.ex
+++ b/lib/lulucat/fsrs_scheduler.ex
@@ -81,6 +81,10 @@ defmodule Fsrs.Scheduler do
     validate_parameters!(parameters)
 
     desired_retention = Keyword.get(opts, :desired_retention, 0.9)
+    validate_desired_retention!(desired_retention)
+
+    maximum_interval = Keyword.get(opts, :maximum_interval, 36500)
+    validate_maximum_interval!(maximum_interval)
 
     # Convert learning_steps and relearning_steps from timedeltas to seconds
     # 将 learning_steps 和 relearning_steps 从时间增量转换为秒
@@ -855,4 +859,20 @@ defmodule Fsrs.Scheduler do
     raise ArgumentError,
           "invalid #{field_name} entry: #{inspect(step)}; expected seconds or {:seconds|:minutes, value}"
   end
+
+  # Validation helpers
+
+  defp validate_desired_retention!(value) do
+    unless is_number(value) and value > 0.0 and value < 1.0 do
+      raise ArgumentError,
+            "desired_retention must be between 0.0 and 1.0 (exclusive), got: #{inspect(value)}"
+    end
+  end
+
+  defp validate_maximum_interval!(value) do
+    unless is_integer(value) and value >= 1 do
+      raise ArgumentError,
+            "maximum_interval must be a positive integer (>= 1), got: #{inspect(value)}"
+    end
+  end
 end