From 97259f4ad31bdb846f7cee8a10f8dd52b06bdf72 Mon Sep 17 00:00:00 2001
From: Alexander Zinchuk <alx.zinchuk@gmail.com>
Date: Sun, 8 Jan 2023 04:04:55 +0100
Subject: [PATCH] Code Highlight: Support Type Language (#2249)

---
 .../common/helpers/renderTextWithEntities.tsx |  2 +-
 src/lib/hljs-tl/typelanguage.js               | 81 +++++++++++++++++++
 src/util/highlightCode.ts                     | 35 ++++++--
 3 files changed, 109 insertions(+), 9 deletions(-)
 create mode 100644 src/lib/hljs-tl/typelanguage.js

diff --git a/src/components/common/helpers/renderTextWithEntities.tsx b/src/components/common/helpers/renderTextWithEntities.tsx
index 5bed9afab..0bcbcc07b 100644
--- a/src/components/common/helpers/renderTextWithEntities.tsx
+++ b/src/components/common/helpers/renderTextWithEntities.tsx
@@ -502,7 +502,7 @@ function processEntityAsHtml(
     case ApiMessageEntityTypes.Code:
       return `<code class="text-entity-code">${renderedContent}</code>`;
     case ApiMessageEntityTypes.Pre:
-      return `\`\`\`${entity.language || ''}<br/>${renderedContent}<br/>\`\`\`<br/>`;
+      return `\`\`\`${renderText(entity.language || '', ['escape_html'])}<br/>${renderedContent}<br/>\`\`\`<br/>`;
     case ApiMessageEntityTypes.Strike:
       return `<del>${renderedContent}</del>`;
     case ApiMessageEntityTypes.MentionName:
diff --git a/src/lib/hljs-tl/typelanguage.js b/src/lib/hljs-tl/typelanguage.js
new file mode 100644
index 000000000..b413a792a
--- /dev/null
+++ b/src/lib/hljs-tl/typelanguage.js
@@ -0,0 +1,81 @@
+export default (hljs) => {
+  const IDENTIFIER_RE = '[a-zA-Z_0-9]+';
+  const IDENTIFIER_WITH_NAMESPACE_RE = '[a-zA-Z_0-9.]+';
+  const TL = [
+    {
+      className: 'keyword',
+      begin: '---',
+      end: '---',
+    },
+    {
+      className: 'number',
+      begin: '#',
+      end: '\\s',
+      excludeBegin: true,
+      excludeEnd: true,
+    },
+    {
+      className: 'punctuation',
+      match: '[:#?=<>]',
+    },
+    {
+      className: 'symbol',
+      match: 'flags\\d*\\.\\d*', // Flagged parameters
+    },
+    {
+      className: 'built_in',
+      match: 'flags:#', // Flags
+    },
+    {
+      className: 'title.class',
+      match: `^${IDENTIFIER_RE}(?=\\.)`, // Namespace
+    },
+    {
+      className: 'title.function',
+      match: `^${IDENTIFIER_RE}(?=[\\s#])`, // Identifier followed by space or #
+    },
+    {
+      className: 'title.function',
+      match: `(?<=\\.)${IDENTIFIER_RE}(?=[\\s#])`, // Identifier after namespace
+    },
+    {
+      className: 'params',
+      match: `(?<=\\s)${IDENTIFIER_RE}(?=:)`, // Parameter name
+    },
+    {
+      className: 'type',
+      match: `(?<=[:?])${IDENTIFIER_WITH_NAMESPACE_RE}(?=\\s)`, // Parameter type
+    },
+    {
+      className: 'variable.constant',
+      match: `(?<=[:?])${IDENTIFIER_RE}(?=<)`, // Generic type
+    },
+    {
+      className: 'type',
+      match: `(?<=<)${IDENTIFIER_RE}(?=>)`, // Type inside angle brackets
+    },
+    {
+      className: 'title.function.invoke',
+      match: `(?<==\\s)${IDENTIFIER_RE}(?=;)`, // Result identifier
+    },
+    {
+      className: 'title.class',
+      match: `(?<==\\s)${IDENTIFIER_RE}(?=\\.)`, // Result namespace
+    },
+    {
+      className: 'title.function.invoke',
+      match: `(?<==\\s${IDENTIFIER_RE}\\.)${IDENTIFIER_RE}(?=;)`, // Result identifier after namespace
+    },
+  ];
+
+  return {
+    name: 'TypeLanguage',
+    aliases: ['tl'],
+    case_insensitive: false,
+    contains: [
+      hljs.C_LINE_COMMENT_MODE,
+      hljs.C_BLOCK_COMMENT_MODE,
+      hljs.C_NUMBER_MODE,
+    ].concat(TL),
+  };
+};
diff --git a/src/util/highlightCode.ts b/src/util/highlightCode.ts
index a4c2b084a..f6b72af79 100644
--- a/src/util/highlightCode.ts
+++ b/src/util/highlightCode.ts
@@ -38,12 +38,15 @@ const SUPPORTED_LANGUAGES: Record<string, string[]> = {
   sql: [],
   swift: [],
   twig: ['craftcms'],
+  typelanguage: ['tl'],
   typescript: ['ts', 'tsx'],
   xml: ['html', 'xhtml', 'rss', 'atom', 'xjb', 'xsd', 'xsl', 'plist', 'wsf', 'svg'],
   yaml: [],
 };
 
-const languagePromises = new Map<string, Promise<void>>();
+const THIRD_PARTY_LANGUAGES = ['typelanguage'];
+
+const languagePromises = new Map<string, Promise<any>>();
 
 export default async function highlightCode(text: string, language: string) {
   const lowLang = language.toLowerCase();
@@ -73,13 +76,10 @@ async function ensureLanguage(language: string) {
     return true;
   }
 
-  // Funky webpack bug https://github.com/webpack/webpack/issues/13865
-  const languagePromise = import(
-    /* webpackChunkName: "Highlight for [request]" */
-    `../../node_modules/highlight.js/lib/languages/${langCode}`
-  );
-  languagePromises.set(langCode, languagePromise);
-  // Allow errors to help debugging wrong language names
+  const languagePromise = THIRD_PARTY_LANGUAGES.includes(langCode)
+    ? loadThirdPartyLanguage(langCode) : loadFirstPartyLanguage(langCode);
+  if (!languagePromise) return false;
+
   const syntax = await languagePromise;
   lowlight.registerLanguage(langCode, syntax.default);
   if (langCode === '1c') {
@@ -88,6 +88,25 @@ async function ensureLanguage(language: string) {
   return true;
 }
 
+function loadFirstPartyLanguage(langCode: string) {
+  // Funky webpack bug https://github.com/webpack/webpack/issues/13865
+  const languagePromise = import(
+    /* webpackChunkName: "Highlight for [request]" */
+    `../../node_modules/highlight.js/lib/languages/${langCode}`
+  );
+  languagePromises.set(langCode, languagePromise);
+  return languagePromise;
+}
+
+function loadThirdPartyLanguage(langCode: string) {
+  if (langCode === 'typelanguage') {
+    const langPromise = import('../lib/hljs-tl/typelanguage');
+    languagePromises.set(langCode, langPromise);
+    return langPromise;
+  }
+  return undefined;
+}
+
 function treeToElements(tree: Element | Root): TeactNode {
   const children = tree.children.map((child) => {
     if (child.type === 'text') {