实现共享试卷考试记录查看功能

功能说明：
- 查看共享试卷的考试记录时，显示所有参与用户的成绩
- 按分数从高到低排序，方便查看排行
- 显示每个用户的头像、昵称和考试详情

实现细节：
1. 后端：修改 GetExamRecordList 接口
   - 指定试卷ID时自动识别共享关系
   - 查询原始试卷+所有分享副本的考试记录
   - 返回用户信息（username, nickname, avatar）
   - 按分数降序排序

2. 前端：更新考试记录展示
   - 显示用户头像和昵称
   - 保持原有的考试详情信息
   - 适配共享和非共享两种场景

修改文件：
- internal/handlers/exam_handler.go: 重构GetExamRecordList逻辑
- web/src/types/exam.ts: ExamRecord添加user字段
- web/src/pages/ExamManagement.tsx: 显示用户信息

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

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

internal/handlers/exam_handler.go

@@ -641,20 +641,73 @@ func GetExamRecordList(c *gin.Context) {
 	examIDStr := c.Query("exam_id")
 
 	db := database.GetDB()
-	query := db.Where("user_id = ?", userID)
 
-	// 如果指定了试卷ID,只查询该试卷的记录
+	// 如果指定了试卷ID，需要判断是否为共享试卷
 	if examIDStr != "" {
 		examID, err := strconv.ParseUint(examIDStr, 10, 32)
 		if err != nil {
 			c.JSON(http.StatusBadRequest, gin.H{"success": false, "message": "无效的试卷ID"})
 			return
 		}
-		query = query.Where("exam_id = ?", examID)
+
+		// 查询试卷信息
+		var exam models.Exam
+		if err := db.Where("id = ? AND user_id = ?", examID, userID).First(&exam).Error; err != nil {
+			c.JSON(http.StatusNotFound, gin.H{"success": false, "message": "试卷不存在或无权限"})
+			return
+		}
+
+		// 获取所有相关试卷ID（包括原始试卷和所有分享副本）
+		var relatedExamIDs []uint
+		relatedExamIDs = append(relatedExamIDs, uint(examID))
+
+		// 如果这是被分享的试卷，找到原始试卷
+		if exam.IsShared && exam.SharedByID != nil {
+			var originalExam models.Exam
+			if err := db.Where("user_id = ? AND question_ids = ? AND deleted_at IS NULL",
+				*exam.SharedByID, exam.QuestionIDs).First(&originalExam).Error; err == nil {
+				relatedExamIDs = append(relatedExamIDs, originalExam.ID)
+			}
+		}
+
+		// 查找所有基于该试卷的分享副本
+		var sharedExams []models.Exam
+		sharedByID := exam.UserID
+		if exam.IsShared && exam.SharedByID != nil {
+			sharedByID = *exam.SharedByID
+		}
+		if err := db.Where("shared_by_id = ? AND question_ids = ? AND deleted_at IS NULL",
+			sharedByID, exam.QuestionIDs).Find(&sharedExams).Error; err == nil {
+			for _, se := range sharedExams {
+				relatedExamIDs = append(relatedExamIDs, se.ID)
+			}
+		}
+
+		// 查询所有相关试卷的考试记录（包含用户信息）
+		var records []models.ExamRecord
+		if err := db.Where("exam_id IN ? AND status = ?", relatedExamIDs, "graded").
+			Preload("Exam").
+			Preload("User", func(db *gorm.DB) *gorm.DB {
+				return db.Select("id", "username", "nickname", "avatar")
+			}).
+			Order("score DESC, created_at DESC").
+			Find(&records).Error; err != nil {
+			log.Printf("查询考试记录失败: %v", err)
+			c.JSON(http.StatusInternalServerError, gin.H{"success": false, "message": "查询考试记录失败"})
+			return
+		}
+
+		c.JSON(http.StatusOK, gin.H{
+			"success": true,
+			"data":    records,
+		})
+		return
 	}
 
+	// 如果没有指定试卷ID，只返回当前用户的记录
 	var records []models.ExamRecord
-	if err := query.Preload("Exam").
+	if err := db.Where("user_id = ?", userID).
+		Preload("Exam").
 		Order("created_at DESC").
 		Find(&records).Error; err != nil {
 		log.Printf("查询考试记录失败: %v", err)

web/src/pages/ExamManagement.tsx

@@ -443,6 +443,14 @@ const ExamManagement: React.FC = () => {
                   style={{ marginBottom: 16 }}
                   size="small"
                 >
+                  {record.user && (
+                    <div style={{ marginBottom: 12, display: 'flex', alignItems: 'center', gap: 8 }}>
+                      <Avatar src={record.user.avatar} icon={<UserOutlined />} />
+                      <span style={{ fontWeight: 'bold' }}>
+                        {record.user.nickname || record.user.username}
+                      </span>
+                    </div>
+                  )}
                   <Descriptions column={1} size="small">
                     <Descriptions.Item label="状态">
                       {record.status === 'in_progress' && <Tag color="processing">进行中</Tag>}

web/src/types/exam.ts

@@ -61,6 +61,12 @@ export interface ExamRecord {
   status: 'in_progress' | 'submitted' | 'graded'
   is_passed: boolean
   exam?: ExamModel
+  user?: {  // 用户信息（共享试卷时返回）
+    id: number
+    username: string
+    nickname: string
+    avatar: string
+  }
   created_at: string
   updated_at: string
 }