M2: 主题系统（sablog经典+modern简约）+ 前台全部页面 + 老 URL 301 兼容 + markdown 双份导入

2026-08-11 17:58:29 +08:00
parent f16bb75538
commit 6214976a88
66 changed files with 2763 additions and 10 deletions
@@ -0,0 +1,101 @@
+<?php
+
+namespace App\Blog\Services;
+
+use App\Models\Post;
+use League\CommonMark\Environment\Environment;
+use League\CommonMark\Extension\CommonMark\CommonMarkCoreExtension;
+use League\CommonMark\Extension\GithubFlavoredMarkdownExtension;
+use League\CommonMark\MarkdownConverter;
+
+class PostContentRenderer
+{
+    private MarkdownConverter $converter;
+
+    public function __construct()
+    {
+        $environment = new Environment([
+            'html_input' => 'allow',
+            'allow_unsafe_links' => true,
+            'max_nesting_level' => 100,
+        ]);
+        $environment->addExtension(new CommonMarkCoreExtension);
+        $environment->addExtension(new GithubFlavoredMarkdownExtension);
+
+        $this->converter = new MarkdownConverter($environment);
+    }
+
+    /**
+     * 将文章内容按格式渲染为 HTML。
+     * markdown -> HTML；html 原样返回。两种格式都会解析附件令牌。
+     */
+    public function render(Post $post): string
+    {
+        $content = $post->content_format === 'markdown'
+            ? $this->toHtml($post->content)
+            : $post->content;
+
+        return $this->renderShortcodes($content, $post);
+    }
+
+    public function toHtml(string $markdown): string
+    {
+        return $this->converter->convert($markdown)->getContent();
+    }
+
+    /**
+     * 解析附件引用。
+     *
+     * 兼容两种写法：
+     *  - 老 sablog HTML 内容： [attach=xx] / [img=xx]
+     *  - markdown 转换导入：  {{attach:xx}} / {{img:xx}}（[] 是 markdown 保留字符，转换时改为令牌）
+     *
+     * xx 是 sablog attachmentid；找不到时回退到按出现顺序的第 N 个附件。
+     */
+    public function renderShortcodes(string $html, Post $post): string
+    {
+        $pattern = '/\[(attach|img)=(\d+)\]|\{\{(attach|img):(\d+)\}\}/';
+
+        if (! preg_match_all($pattern, $html, $matches, PREG_SET_ORDER)) {
+            return $html;
+        }
+
+        $mediaItems = $post->getMedia('attachments');
+        $byLegacyId = $mediaItems->keyBy(fn ($m) => (int) $m->getCustomProperty('legacy_attachmentid'));
+        $ordered = $mediaItems->values();
+
+        foreach ($matches as $match) {
+            $full = $match[0];
+            $type = $match[1] !== '' ? $match[1] : $match[3];
+            $id = (int) ($match[2] !== '' ? $match[2] : $match[4]);
+
+            $media = $byLegacyId->get($id);
+
+            if (! $media) {
+                // 兼容按索引引用的旧写法：第 $id 个附件（从 1 开始）
+                $media = $ordered->get($id - 1);
+            }
+
+            if (! $media) {
+                continue;
+            }
+
+            $replacement = $type === 'img'
+                ? sprintf('<img src="%s" alt="%s" loading="lazy" />', $media->getUrl(), e($media->name))
+                : sprintf('<a href="%s">%s</a>', $media->getUrl(), e($media->file_name));
+
+            $html = str_replace($full, $replacement, $html);
+        }
+
+        return $html;
+    }
+
+    /**
+     * 把老 sablog HTML 里的 [attach=xx]/[img=xx] 换成 markdown 安全令牌，
+     * 供 HTML -> markdown 转换前调用。
+     */
+    public function toMarkdownSafeTokens(string $html): string
+    {
+        return preg_replace('/\[(attach|img)=(\d+)\]/', '{{$1:$2}}', $html);
+    }
+}