From 9f4c3ed35ac44c9edfe1d7b37c038cffb58d89c5 Mon Sep 17 00:00:00 2001
From: Elian Doran <contact@eliandoran.me>
Date: Fri, 17 Apr 2026 07:49:38 +0300
Subject: [PATCH] feat(markdown): basic support hash-based wikilinks

---
 .../type_widgets/code/Markdown.spec.ts        |  6 +++++
 .../widgets/type_widgets/code/Markdown.tsx    |  5 +++-
 packages/commons/src/lib/markdown_renderer.ts | 23 +++++++++++++++++--
 3 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/apps/client/src/widgets/type_widgets/code/Markdown.spec.ts b/apps/client/src/widgets/type_widgets/code/Markdown.spec.ts
index aeb1aa1f41..61cf206417 100644
--- a/apps/client/src/widgets/type_widgets/code/Markdown.spec.ts
+++ b/apps/client/src/widgets/type_widgets/code/Markdown.spec.ts
@@ -79,4 +79,10 @@ describe("renderWithSourceLines", () => {
         const html = renderWithSourceLines("Energy: $e=mc^2$.");
         expect(html).toContain('<span class="math-tex">');
     });
+
+    it("renders [[wikilinks]] with hash-router hrefs so the preview navigates correctly", () => {
+        const html = renderWithSourceLines("See [[abc123]] for details.");
+        expect(html).toContain('class="reference-link"');
+        expect(html).toContain('href="#root/abc123"');
+    });
 });
diff --git a/apps/client/src/widgets/type_widgets/code/Markdown.tsx b/apps/client/src/widgets/type_widgets/code/Markdown.tsx
index 66c9fa0c90..ace105e7a5 100644
--- a/apps/client/src/widgets/type_widgets/code/Markdown.tsx
+++ b/apps/client/src/widgets/type_widgets/code/Markdown.tsx
@@ -149,7 +149,10 @@ export function renderWithSourceLines(src: string): string {
         if (!NON_RENDERED_TOKENS.has(token.type)) lines.push(startLine);
     }
 
-    const html = renderToHtml(src, "", { sanitize: (h) => DOMPurify.sanitize(h) });
+    const html = renderToHtml(src, "", {
+        sanitize: (h) => DOMPurify.sanitize(h),
+        wikiLink: { formatHref: (id) => `#root/${id}` }
+    });
     if (!html) return "";
 
     const container = document.createElement("div");
diff --git a/packages/commons/src/lib/markdown_renderer.ts b/packages/commons/src/lib/markdown_renderer.ts
index 865880e190..453c39d420 100644
--- a/packages/commons/src/lib/markdown_renderer.ts
+++ b/packages/commons/src/lib/markdown_renderer.ts
@@ -1,7 +1,14 @@
 import { Marked, Renderer, type Tokens } from "marked";
 
 import { getMimeTypeFromMarkdownName, MIME_TYPE_AUTO, normalizeMimeTypeForCKEditor } from "./mime_type.js";
-import { transclusionExtension, wikiLinkExtension } from "./marked_extensions.js";
+import {
+    createTransclusionExtension,
+    createWikiLinkExtension,
+    transclusionExtension,
+    type TransclusionOptions,
+    wikiLinkExtension,
+    type WikiLinkOptions
+} from "./marked_extensions.js";
 
 /**
  * Mapping from markdown admonition keywords (case-insensitive) to the ids
@@ -24,6 +31,15 @@ export interface RenderToHtmlOptions {
      *  - client: `DOMPurify.sanitize`
      */
     sanitize: (dirtyHtml: string) => string;
+    /**
+     * How `[[noteId]]` wiki-links should be rendered. Defaults to the
+     * server-side format (`href="/noteId"`), which is what imports want.
+     * Browser callers that navigate via the hash router should pass
+     * `{ formatHref: (id) => `#root/${id}` }`.
+     */
+    wikiLink?: WikiLinkOptions;
+    /** Same as {@link wikiLink}, for `![[noteId]]` transclusions. */
+    transclusion?: TransclusionOptions;
 }
 
 function escapeHtml(str: string): string {
@@ -253,7 +269,10 @@ export function renderToHtml(content: string, title: string, options: RenderToHt
     const marked = new Marked({ async: false });
     marked.use({
         // Order is important, especially for wikilinks.
-        extensions: [ transclusionExtension, wikiLinkExtension ]
+        extensions: [
+            options.transclusion ? createTransclusionExtension(options.transclusion) : transclusionExtension,
+            options.wikiLink ? createWikiLinkExtension(options.wikiLink) : wikiLinkExtension
+        ]
     });
 
     const renderer = new CustomMarkdownRenderer({ async: false });