Update: TTS settings modal and settings types

src/utils/srs.ts

@@ -1,23 +1,58 @@
 import type { StudyProgress, DifficultyRating } from '../types/vocabulary';
 
+interface SRSConfig {
+  initialEase: number;
+  minEase: number;
+  maxInterval: number;
+  learningStepInterval: number;
+}
+
+const DEFAULT_CONFIG: SRSConfig = {
+  initialEase: 2.5,
+  minEase: 1.3,
+  maxInterval: 365, // 最大间隔 365 天
+  learningStepInterval: 10, // 学习步骤间隔（分钟）
+};
+
+/**
+ * 改进的 SM-2 算法实现
+ * 基于 Anki 和 SuperMemo 的研究
+ */
 export function calculateNextReview(
   progress: StudyProgress,
-  rating: DifficultyRating
+  rating: DifficultyRating,
+  config: SRSConfig = DEFAULT_CONFIG
 ): StudyProgress {
   const newProgress = { ...progress };
+  const { minEase, maxInterval } = config;
   
+  // 如果是新单词（repetitions === 0），使用学习步骤
+  if (progress.repetitions === 0 && rating === 'again') {
+    // 标记为"再次"，保持在第一步
+    newProgress.interval = 0;
+    newProgress.easeFactor = Math.max(minEase, progress.easeFactor - 0.2);
+    newProgress.nextReviewDate = new Date(Date.now() + DEFAULT_CONFIG.learningStepInterval * 60 * 1000);
+    newProgress.lastStudiedDate = new Date();
+    return newProgress;
+  }
+
   switch (rating) {
     case 'again':
+      // 完全重置，但保留一些学习历史
       newProgress.interval = 1;
       newProgress.repetitions = 0;
-      newProgress.easeFactor = Math.max(1.3, progress.easeFactor - 0.2);
+      newProgress.easeFactor = Math.max(minEase, progress.easeFactor - 0.2);
       break;
+      
     case 'hard':
-      newProgress.interval = Math.round(progress.interval * 1.2);
+      // 困难：间隔增长较慢
+      newProgress.interval = Math.max(1, Math.round(progress.interval * 1.2));
       newProgress.repetitions += 1;
-      newProgress.easeFactor = Math.max(1.3, progress.easeFactor - 0.15);
+      newProgress.easeFactor = Math.max(minEase, progress.easeFactor - 0.15);
       break;
+      
     case 'good':
+      // 良好：标准 SM-2 算法
       if (progress.repetitions === 0) {
         newProgress.interval = 1;
       } else if (progress.repetitions === 1) {
@@ -27,7 +62,9 @@ export function calculateNextReview(
       }
       newProgress.repetitions += 1;
       break;
+      
     case 'easy':
+      // 简单：间隔增长更快
       if (progress.repetitions === 0) {
         newProgress.interval = 4;
       } else {
@@ -38,9 +75,52 @@ export function calculateNextReview(
       break;
   }
   
+  // 限制最大间隔
+  newProgress.interval = Math.min(newProgress.interval, maxInterval);
+  
+  // 确保 easeFactor 在合理范围内
+  newProgress.easeFactor = Math.max(minEase, Math.min(newProgress.easeFactor, 3.0));
+  
+  // 计算下次复习日期
   const now = new Date();
   newProgress.nextReviewDate = new Date(now.getTime() + newProgress.interval * 24 * 60 * 60 * 1000);
   newProgress.lastStudiedDate = now;
   
   return newProgress;
 }
+
+/**
+ * 计算单词的掌握程度 (0-100%)
+ */
+export function calculateMastery(progress: StudyProgress): number {
+  if (progress.repetitions === 0) return 0;
+  
+  const baseScore = Math.min(progress.repetitions * 20, 80);
+  const intervalBonus = Math.min(progress.interval / 30 * 20, 20);
+  
+  return Math.min(100, Math.round(baseScore + intervalBonus));
+}
+
+/**
+ * 获取复习优先级分数（越高越优先）
+ */
+export function getReviewPriority(progress: StudyProgress): number {
+  const now = new Date();
+  const nextReview = new Date(progress.nextReviewDate);
+  const overdue = now.getTime() - nextReview.getTime();
+  
+  // 逾期的单词优先级更高
+  if (overdue > 0) {
+    return 1000 + Math.min(overdue / (1000 * 60 * 60), 1000); // 每小时增加 1 点优先级
+  }
+  
+  // 即将到期的单词
+  const timeUntilDue = nextReview.getTime() - now.getTime();
+  const hoursUntilDue = timeUntilDue / (1000 * 60 * 60);
+  
+  if (hoursUntilDue < 24) {
+    return 500 + (24 - hoursUntilDue) * 20;
+  }
+  
+  return hoursUntilDue;
+}