fix: use pdf previews for documents

app/Http/Controllers/DocumentController.php

@@ -3,27 +3,25 @@
 namespace App\Http\Controllers;
 
 use App\Models\Document;
+use App\Services\DocumentPdfPreviewService;
 use App\Services\DocumentService;
-use App\Services\MarkdownRenderService;
-use Illuminate\Http\Request;
 use Illuminate\Support\Facades\Gate;
-use Illuminate\Support\Facades\Storage;
 
 class DocumentController extends Controller
 {
     protected DocumentService $documentService;
-    protected MarkdownRenderService $markdownRenderService;
+    protected DocumentPdfPreviewService $pdfPreviewService;
 
     public function __construct(
         DocumentService $documentService,
-        MarkdownRenderService $markdownRenderService
+        DocumentPdfPreviewService $pdfPreviewService
     ) {
         $this->documentService = $documentService;
-        $this->markdownRenderService = $markdownRenderService;
+        $this->pdfPreviewService = $pdfPreviewService;
     }
 
     /**
-     * 预览文档的 Markdown 内容（支持图片显示）
+     * 预览文档的 PDF 内容
      * 需求：11.1, 11.3, 11.4
      * 
      * @param Document $document
@@ -31,42 +29,37 @@ class DocumentController extends Controller
      */
     public function preview(Document $document)
     {
-        // 验证用户权限（使用 DocumentPolicy）
-        // 需求：11.3
         if (!Gate::allows('view', $document)) {
             abort(403, '您没有权限预览此文档');
         }
 
-        // 检查文档是否已完成转换
-        if ($document->conversion_status !== 'completed') {
-            return view('documents.preview', [
-                'document' => $document,
-                'markdownHtml' => null,
-            ]);
+        return view('documents.preview', [
+            'document' => $document,
+            'canPreviewPdf' => $this->pdfPreviewService->canPreview($document),
+            'previewPdfUrl' => $this->pdfPreviewService->previewUrl($document),
+        ]);
+    }
+
+    public function previewPdf(Document $document)
+    {
+        if (! Gate::allows('view', $document)) {
+            abort(403, '您没有权限预览此文档');
         }
 
-        $markdownHtml = null;
-
         try {
-            // 使用 DocumentPreviewService 的 Markdown 预览方法
-            // 这会修复图片路径并渲染 Markdown
-            // 需求：11.1
-            $previewService = app(\App\Services\DocumentPreviewService::class);
-            $markdownHtml = $previewService->convertMarkdownToHtml($document);
-        } catch (\Exception $e) {
-            // 记录错误但不中断流程
-            \Log::error('Markdown 预览失败', [
+            $path = $this->pdfPreviewService->getPreviewPath($document);
+        } catch (\Throwable $e) {
+            \Log::error('PDF 预览生成失败', [
                 'document_id' => $document->id,
                 'error' => $e->getMessage(),
             ]);
+
+            abort(500, 'PDF 预览生成失败：' . $e->getMessage());
         }
 
-        // 处理内容为空的情况
-        // 需求：11.4
-        // 返回渲染后的 HTML 视图
-        return view('documents.preview', [
-            'document' => $document,
-            'markdownHtml' => $markdownHtml,
+        return response()->file($path, [
+            'Content-Type' => 'application/pdf',
+            'Content-Disposition' => 'inline; filename="document-' . $document->getKey() . '.pdf"',
         ]);
     }