fix(editor): add footnote url markdown preprocessor to avoid link node parsing (#11888)

Closes: [BS-3282](https://linear.app/affine-design/issue/BS-3282/预处理-footnote-definition-中的-url-避免-markdown-link-node-parsing)

blocksuite/affine/blocks/bookmark/src/adapters/extension.ts

@@ -1,13 +1,13 @@
 import type { ExtensionType } from '@blocksuite/store';
 
 import { BookmarkBlockHtmlAdapterExtension } from './html.js';
-import { BookmarkBlockMarkdownAdapterExtension } from './markdown.js';
+import { BookmarkBlockMarkdownAdapterExtensions } from './markdown/index.js';
 import { BookmarkBlockNotionHtmlAdapterExtension } from './notion-html.js';
 import { BookmarkBlockPlainTextAdapterExtension } from './plain-text.js';
 
 export const BookmarkBlockAdapterExtensions: ExtensionType[] = [
   BookmarkBlockHtmlAdapterExtension,
-  BookmarkBlockMarkdownAdapterExtension,
+  BookmarkBlockMarkdownAdapterExtensions,
   BookmarkBlockNotionHtmlAdapterExtension,
   BookmarkBlockPlainTextAdapterExtension,
-];
+].flat();

blocksuite/affine/blocks/bookmark/src/adapters/index.ts

@@ -1,4 +1,4 @@
 export * from './html.js';
-export * from './markdown.js';
+export * from './markdown/index.js';
 export * from './notion-html.js';
 export * from './plain-text.js';

blocksuite/affine/blocks/bookmark/src/adapters/markdown/index.ts

@@ -0,0 +1,12 @@
+import type { ExtensionType } from '@blocksuite/store';
+
+import { BookmarkBlockMarkdownAdapterExtension } from './markdown.js';
+import { BookmarkBlockMarkdownPreprocessorExtension } from './preprocessor.js';
+
+export * from './markdown.js';
+export * from './preprocessor.js';
+
+export const BookmarkBlockMarkdownAdapterExtensions: ExtensionType[] = [
+  BookmarkBlockMarkdownPreprocessorExtension,
+  BookmarkBlockMarkdownAdapterExtension,
+];

blocksuite/affine/blocks/bookmark/src/adapters/markdown/preprocessor.ts

@@ -0,0 +1,67 @@
+import {
+  type MarkdownAdapterPreprocessor,
+  MarkdownPreprocessorExtension,
+} from '@blocksuite/affine-shared/adapters';
+
+// Check if a URL is already encoded with encodeURIComponent
+function isEncoded(uri: string): boolean {
+  try {
+    // If decoding produces a different result than the original,
+    // then the URI contains encoded characters
+    return uri !== decodeURIComponent(uri);
+  } catch {
+    // If decoding fails, the URI contains invalid percent-encoding
+    return true;
+  }
+}
+
+// Format footnote definition with consistent spacing
+function formatFootnoteDefinition(reference: string, data: object): string {
+  return `[^${reference}]: ${JSON.stringify(data)}`;
+}
+
+/**
+ * Preprocessor for footnote url
+ * We should encode url in footnote definition to avoid markdown link parsing
+ *
+ * Example of footnote definition:
+ * [^ref]: {"type":"url","url":"https://example.com"}
+ */
+export function footnoteUrlPreprocessor(content: string): string {
+  // Match footnote definitions with any reference (not just numbers)
+  // Format: [^reference]: {json_content}
+  return content.replace(
+    /\[\^([^\]]+)\]:\s*({[\s\S]*?})/g,
+    (match, reference, jsonContent) => {
+      try {
+        const footnoteData = JSON.parse(jsonContent.trim());
+        // If footnoteData is not an object or doesn't have url, return original content
+        // If the url is already encoded, return original content
+        if (
+          typeof footnoteData !== 'object' ||
+          !footnoteData.url ||
+          isEncoded(footnoteData.url)
+        ) {
+          return match;
+        }
+
+        return formatFootnoteDefinition(reference, {
+          ...footnoteData,
+          url: encodeURIComponent(footnoteData.url),
+        });
+      } catch {
+        // Keep original content if JSON parsing fails
+        return match;
+      }
+    }
+  );
+}
+
+const bookmarkBlockPreprocessor: MarkdownAdapterPreprocessor = {
+  name: 'bookmark-block',
+  levels: ['block', 'slice', 'doc'],
+  preprocess: footnoteUrlPreprocessor,
+};
+
+export const BookmarkBlockMarkdownPreprocessorExtension =
+  MarkdownPreprocessorExtension(bookmarkBlockPreprocessor);