fix: 修复文档转换与预览链路中的图片、文件名和错误处理问题

app/Models/Document.php

@@ -7,6 +7,7 @@ use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Support\Facades\Storage;
+use Illuminate\Support\Str;
 use Laravel\Scout\Searchable;
 
 class Document extends Model
@@ -114,4 +115,33 @@ class Document extends Model
     {
         return !empty($this->markdown_path) && $this->conversion_status === 'completed';
     }
+
+    /**
+     * 获取用于展示和下载的文件名
+     * 对历史上误保存为随机存储名的记录回退到“标题.扩展名”
+     */
+    public function getDisplayFileNameAttribute(): string
+    {
+        $fileName = trim((string) $this->file_name);
+
+        if ($fileName !== '' && ! $this->looksLikeGeneratedStorageName($fileName)) {
+            return $fileName;
+        }
+
+        $extension = pathinfo($fileName ?: $this->file_path, PATHINFO_EXTENSION);
+        $title = trim((string) $this->title);
+        $title = preg_replace('/[<>:"\/\\\\|?*\x00-\x1F]+/u', '-', $title) ?? '';
+        $title = trim($title, " .-\t\n\r\0\x0B");
+        $title = $title !== '' ? $title : 'document';
+
+        return $extension !== '' ? "{$title}.{$extension}" : $title;
+    }
+
+    protected function looksLikeGeneratedStorageName(string $fileName): bool
+    {
+        $baseName = pathinfo($fileName, PATHINFO_FILENAME);
+
+        return Str::isUuid($baseName)
+            || (bool) preg_match('/^[0-9A-HJKMNP-TV-Z]{26}$/i', $baseName);
+    }
 }