Fallback to raw LLM content when JSON parsing fails

backend/main.go

@@ -16,6 +16,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -733,11 +734,8 @@ func (c *LLMClient) FormatAndGrade(ctx context.Context, title, ocrText string) (
 
 	result := LLMResult{}
 	if err := decodeLLMResult(content, &result); err != nil {
-		fallback := strings.TrimSpace(content)
+		markdown, feedback, score := fallbackFromContent(content, ocrText)
-		if fallback == "" {
+		return markdown, feedback, score, nil
-			fallback = ocrText
-		}
-		return fallback, "LLM 返回无法解析为 JSON，已返回原始内容。", 0, nil
 	}
 
 	markdown := strings.TrimSpace(result.Markdown)
@@ -792,7 +790,8 @@ func (c *LLMClient) FormatAndGradeFromImages(ctx context.Context, title string,
 
 	result := LLMResult{}
 	if err := decodeLLMResult(content, &result); err != nil {
-		return "", "LLM 返回无法解析为 JSON。", 0, nil
+		markdown, feedback, score := fallbackFromContent(content, "未识别到有效内容。")
+		return markdown, feedback, score, nil
 	}
 
 	markdown := strings.TrimSpace(result.Markdown)
@@ -896,6 +895,35 @@ func decodeLLMResult(content string, out *LLMResult) error {
 	return nil
 }
 
+var scorePattern = regexp.MustCompile(`(?i)(?:评分|score)[:：]?\s*([0-9]{1,3})`)
+
+func parseScoreFromText(text string) int {
+	matches := scorePattern.FindStringSubmatch(text)
+	if len(matches) < 2 {
+		return 0
+	}
+	value, err := strconv.Atoi(matches[1])
+	if err != nil {
+		return 0
+	}
+	if value < 0 {
+		return 0
+	}
+	if value > 100 {
+		return 100
+	}
+	return value
+}
+
+func fallbackFromContent(content, defaultMarkdown string) (string, string, int) {
+	markdown := strings.TrimSpace(content)
+	if markdown == "" {
+		markdown = defaultMarkdown
+	}
+	score := parseScoreFromText(markdown)
+	return markdown, "", score
+}
+
 func ensureColumn(db *sql.DB, table, column, columnType string) error {
 	rows, err := db.Query(fmt.Sprintf("PRAGMA table_info(%s);", table))
 	if err != nil {