增加一个图片文件转存的功能

web/admin/md_check.php

@@ -1,17 +1,34 @@
 <?php
-function decodeMarkdownEntities($markdown) {
-    // Decode HTML entities in code blocks
-    // $markdown = preg_replace_callback('/(```.*?```|`[^`]*`)/s', function ($matches) {
-    //     return htmlentities($matches[0], ENT_QUOTES, 'UTF-8');
-    // }, $markdown);
-    // Remove <br /> tags in code blocks
-    $markdown = preg_replace_callback('/(```.*?```|`[^`]*`)/s', function ($matches) {
-        return str_replace('<br />', '', $matches[0]);
+function downloadImage($url, $saveDir) {
+    // 获取图片内容
+    $imageContent = file_get_contents($url);
+    if ($imageContent === FALSE) {
+        return $url;
+    }
+
+    // 生成唯一的文件名
+    $imageName = uniqid() . basename($url);
+    $savePath = rtrim($saveDir, '/') . '/' . $imageName;
+
+    // 保存图片到本地
+    if (file_put_contents($savePath, $imageContent) === FALSE) {
+        return $url;
+    }
+
+    // 返回保存路径
+    return $savePath;
+}
+function MarkdownEntities($markdown) {
+    // 对markdown中的内容进行转义
+    $markdown = preg_replace_callback('/\$\$(.*?)\$\$/s', function ($matches) {
+        return str_replace(['<', '>'], ['\\lt', '\\gt'], $matches[0]);
     }, $markdown);
-    
-    // Decode HTML entities in inline math and display math
-    $markdown = preg_replace_callback('/(\$\$.*?\$\$|\$[^$]*\$)/s', function ($matches) {
-        return htmlentities($matches[0], ENT_QUOTES, 'UTF-8');
+    // 对图片内容存储到本机并替换
+    $saveDir = __DIR__ . "/../../upload/markdown";
+    $markdown = preg_replace_callback('/!\[.*?\]\((.*?)\)/', function ($matches) use ($saveDir) {
+        $imageUrl = $matches[1];
+        $savedPath = downloadImage($imageUrl, $saveDir);
+        return str_replace($imageUrl, $savedPath, $matches[0]);
     }, $markdown);
     return $markdown;
 }