From 45717816a2cd4a0336e2710257561d9352e62d7b Mon Sep 17 00:00:00 2001
From: Yifei Gao <jasongao97@gmail.com>
Date: Wed, 3 Jul 2024 01:05:04 +0800
Subject: [PATCH] [feature] support video link with headings

---
 gatsby/lib/parse-content.mjs | 29 +++++++++++++++++++++++------
 src/components/VideoLink.js  | 26 ++++++++++++++++++++++++++
 src/layouts/ChapterLayout.js |  2 ++
 3 files changed, 51 insertions(+), 6 deletions(-)
 create mode 100644 src/components/VideoLink.js

diff --git a/gatsby/lib/parse-content.mjs b/gatsby/lib/parse-content.mjs
index c46524a..94e52a7 100644
--- a/gatsby/lib/parse-content.mjs
+++ b/gatsby/lib/parse-content.mjs
@@ -11,9 +11,13 @@ import { toString } from 'hast-util-to-string';
 
 import { rehypeCodesplit } from './codesplit.mjs';
 
+function isHeading(node) {
+  return node.type === 'element' && /^h[1-6]$/i.test(node.tagName);
+}
+
 export function parseContent(html) {
   const replaceMedia = () => (tree) => {
-    visit(tree, { tagName: 'div' }, (node) => {
+    visit(tree, { tagName: 'div' }, (node, index, parent) => {
       if (
         node.properties.className &&
         Array.isArray(node.properties.className) &&
@@ -44,6 +48,19 @@ export function parseContent(html) {
         node.tagName = 'embed-example';
       }
 
+      if (
+        node.properties.dataType === 'video-link' &&
+        node.properties.dataTitle &&
+        index > 2 &&
+        isHeading(parent.children[index - 2])
+      ) {
+        node.tagName = 'video-link';
+
+        // move the video-link node inside the last adjacent heading
+        parent.children[index - 2].children.push(node);
+        parent.children.splice(index, 1);
+      }
+
       if (
         node.properties.dataType === 'note' ||
         node.properties.dataType === 'exercise' ||
@@ -151,11 +168,6 @@ export function parseContent(html) {
   const description = paragraphs.join(' ').trim().substring(0, 150);
 
   const transformedAst = unified()
-    .use(replaceMedia)
-    .use(externalLinkInNewTab)
-    .use(rehypeCodesplit)
-    .use(rehypeHighlight)
-    .use(rehypeSlug)
     .use(rehypeAutolinkHeadings, {
       behavior: 'wrap',
       test: ['h2', 'h3'],
@@ -163,6 +175,11 @@ export function parseContent(html) {
         class: 'heading-link',
       },
     })
+    .use(replaceMedia)
+    .use(externalLinkInNewTab)
+    .use(rehypeCodesplit)
+    .use(rehypeHighlight)
+    .use(rehypeSlug)
     .use(rehypeKatex)
     .runSync(ast);
 
diff --git a/src/components/VideoLink.js b/src/components/VideoLink.js
new file mode 100644
index 0000000..987a3d1
--- /dev/null
+++ b/src/components/VideoLink.js
@@ -0,0 +1,26 @@
+import React from 'react';
+import { FaYoutube } from 'react-icons/fa';
+
+const VideoLink = (props) => {
+  return (
+    <div className="ml-6 inline-block">
+      <a
+        className="group relative flex items-center gap-2 text-base text-noc-400 no-underline"
+        href={props['href']}
+      >
+        <FaYoutube />
+        {props['data-title']}
+
+        {props.children && (
+          <div className="not-prose absolute top-0 hidden w-80 pt-10 group-hover:block">
+            <div className="rounded-lg bg-noc-500 bg-opacity-50 p-4">
+              {props.children}
+            </div>
+          </div>
+        )}
+      </a>
+    </div>
+  );
+};
+
+export default VideoLink;
diff --git a/src/layouts/ChapterLayout.js b/src/layouts/ChapterLayout.js
index ad97d03..f3265d2 100644
--- a/src/layouts/ChapterLayout.js
+++ b/src/layouts/ChapterLayout.js
@@ -8,6 +8,7 @@ import SideNavLayout from './SideNavLayout';
 import PrevNextButtons from '../components/PrevNextButtons';
 import Image from '../components/Image';
 import Example from '../components/Example';
+import VideoLink from '../components/VideoLink';
 
 const renderAst = ({ ast, images }) => {
   visit(ast, { tagName: 'img' }, (node) => {
@@ -29,6 +30,7 @@ const renderAst = ({ ast, images }) => {
     components: {
       'gatsby-image': Image,
       'embed-example': Example,
+      'video-link': VideoLink,
     },
   });