quiz resetc

internal/repository/quiz_repo.go

@@ -341,6 +341,20 @@ func (r *QuizRepo) QuestionStats(ctx context.Context, quizID string) ([]model.Qu
 	return out, nil
 }
 
+// ResetAttempt deletes one person's attempt — its answers go with it — so the
+// quiz is pending for them again and they can take it afresh.
+func (r *QuizRepo) ResetAttempt(ctx context.Context, quizID, userID string) error {
+	tag, err := r.pg.Pool.Exec(ctx,
+		`DELETE FROM quiz_attempts WHERE quiz_id = $1 AND user_id = $2`, quizID, userID)
+	if err != nil {
+		return fmt.Errorf("reset attempt: %w", err)
+	}
+	if tag.RowsAffected() == 0 {
+		return ErrQuizNotStarted
+	}
+	return nil
+}
+
 // ── Taking a quiz ─────────────────────────────────────────────────────────
 
 // PublishedForPath returns the newest live quiz on a content page, or nil.