添加每日一练排行榜功能

- 修复 daily_exam_service.go 中的类型转换错误
- 在首页添加每日一练排行榜组件
- 显示今日每日一练的考试成绩和用时排行
- 当今日尚未生成每日一练时显示友好提示

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

internal/services/daily_exam_service.go

@@ -75,7 +75,7 @@ func (s *DailyExamService) GenerateDailyExam() error {
 	}
 
 	exam := models.Exam{
-		UserID:      firstUser.ID, // 使用第一个用户作为创建者
+		UserID:      uint(firstUser.ID), // 使用第一个用户作为创建者
 		Title:       title,
 		TotalScore:  int(totalScore),
 		Duration:    60,
@@ -92,7 +92,7 @@ func (s *DailyExamService) GenerateDailyExam() error {
 	log.Printf("成功创建每日一练试卷: ID=%d, Title=%s", exam.ID, exam.Title)
 
 	// 6. 分享给所有用户
-	if err := s.shareToAllUsers(exam.ID, firstUser.ID); err != nil {
+	if err := s.shareToAllUsers(exam.ID, uint(firstUser.ID)); err != nil {
 		log.Printf("分享试卷失败: %v", err)
 		// 不返回错误，因为试卷已创建成功
 	}

web/src/pages/Home.tsx

@@ -24,6 +24,7 @@ import {
   CrownOutlined,
 } from '@ant-design/icons'
 import * as questionApi from '../api/question'
+import * as examApi from '../api/exam'
 import { fetchWithAuth } from '../utils/request'
 import type { Statistics } from '../types/question'
 import styles from './Home.module.less'
@@ -110,6 +111,23 @@ const Home: React.FC = () => {
   const [rankingType, setRankingType] = useState<'daily' | 'total'>('daily') // 排行榜类型：每日或总榜
   const [sliderPosition, setSliderPosition] = useState<'left' | 'right'>('left') // 滑块位置
 
+  // 每日一练排行榜状态
+  const [dailyExamRanking, setDailyExamRanking] = useState<{
+    exam_id?: number
+    exam_title?: string
+    rankings: Array<{
+      user_id: number
+      username: string
+      nickname: string
+      avatar: string
+      score: number
+      time_spent: number
+      rank: number
+    }>
+    total: number
+  }>({ rankings: [], total: 0 })
+  const [dailyExamLoading, setDailyExamLoading] = useState(false)
+
   // 答题设置状态
   const [autoNext, setAutoNext] = useState(() => {
     const saved = localStorage.getItem('autoNextEnabled')
@@ -183,6 +201,23 @@ const Home: React.FC = () => {
     setSliderPosition(type === 'daily' ? 'left' : 'right')
   }
 
+  // 加载每日一练排行榜
+  const loadDailyExamRanking = async () => {
+    setDailyExamLoading(true)
+    try {
+      const res = await examApi.getDailyExamRanking()
+      if (res.success && res.data) {
+        setDailyExamRanking(res.data)
+      }
+    } catch (error) {
+      console.error('加载每日一练排行榜失败:', error)
+      // 如果失败，设置为空数据（可能是今日尚未生成）
+      setDailyExamRanking({ rankings: [], total: 0 })
+    } finally {
+      setDailyExamLoading(false)
+    }
+  }
+
   // 加载用户信息
   useEffect(() => {
     const token = localStorage.getItem('token')
@@ -206,6 +241,7 @@ const Home: React.FC = () => {
   useEffect(() => {
     loadStatistics()
     loadCurrentRanking()
+    loadDailyExamRanking()
   }, [rankingType])
 
   // 动态加载聊天插件（仅在首页加载）
@@ -823,6 +859,88 @@ const Home: React.FC = () => {
         )}
       </div>
 
+      {/* 每日一练排行榜 */}
+      <div className={styles.rankingSection}>
+        <Title level={4} className={styles.sectionTitle}>
+          <CrownOutlined style={{ color: '#fa8c16' }} /> 每日一练排行榜
+        </Title>
+        {dailyExamLoading ? (
+          <Card className={styles.rankingCard} loading={true} />
+        ) : dailyExamRanking.rankings.length === 0 ? (
+          <Card className={styles.rankingCard}>
+            <div style={{ textAlign: 'center', padding: '40px 20px', color: '#8c8c8c' }}>
+              <CrownOutlined style={{ fontSize: 48, marginBottom: 16, opacity: 0.3, color: '#fa8c16' }} />
+              <div>今日每日一练尚未生成</div>
+              <div style={{ fontSize: 13, marginTop: 8 }}>请等待系统每天凌晨1点自动生成</div>
+            </div>
+          </Card>
+        ) : (
+          <Card className={styles.rankingCard}>
+            {dailyExamRanking.exam_title && (
+              <div style={{
+                padding: '12px 16px',
+                background: 'linear-gradient(135deg, #fff7e6 0%, #ffe7ba 100%)',
+                borderRadius: '8px',
+                marginBottom: '16px',
+                display: 'flex',
+                alignItems: 'center',
+                gap: '8px'
+              }}>
+                <FileTextOutlined style={{ color: '#fa8c16', fontSize: 16 }} />
+                <Text strong style={{ color: '#fa8c16' }}>{dailyExamRanking.exam_title}</Text>
+              </div>
+            )}
+            <div className={styles.rankingList}>
+              {dailyExamRanking.rankings.map((user, index) => (
+                <div key={user.user_id} className={styles.rankingItem}>
+                  <div className={styles.rankingLeft}>
+                    {index < 3 ? (
+                      <div className={`${styles.rankBadge} ${styles[`rank${index + 1}`]}`}>
+                        {index === 0 && <CrownOutlined />}
+                        {index === 1 && <CrownOutlined />}
+                        {index === 2 && <CrownOutlined />}
+                      </div>
+                    ) : (
+                      <div className={styles.rankNumber}>{index + 1}</div>
+                    )}
+                    <Avatar
+                      src={user.avatar || undefined}
+                      size={40}
+                      icon={<UserOutlined />}
+                      className={styles.rankAvatar}
+                    />
+                    <div className={styles.rankUserInfo}>
+                      <div className={styles.rankNickname}>{user.nickname}</div>
+                      <div className={styles.rankUsername}>@{user.username}</div>
+                    </div>
+                  </div>
+                  <div className={styles.rankingRight}>
+                    <div className={styles.rankStat}>
+                      <div className={styles.rankStatValue} style={{
+                        color: user.score >= 80 ? '#52c41a' : user.score >= 60 ? '#faad14' : '#ff4d4f',
+                        fontSize: 18,
+                        fontWeight: 'bold'
+                      }}>
+                        {user.score}
+                      </div>
+                      <div className={styles.rankStatLabel}>得分</div>
+                    </div>
+                    <div className={styles.rankDivider}></div>
+                    <div className={styles.rankStat}>
+                      <div className={styles.rankStatValue}>
+                        {Math.floor(user.time_spent / 60)}'
+                        {user.time_spent % 60 < 10 ? '0' : ''}{user.time_spent % 60}"
+                      </div>
+                      <div className={styles.rankStatLabel}>用时</div>
+                    </div>
+                  </div>
+                </div>
+              ))}
+            </div>
+          </Card>
+        )}
+      </div>
+
       {/* 用户类型补充模态框 */}
       <Modal
         title="请选择您的身份类型"